{"gene":"PF3D7_1133400","run_date":"2026-09-08T12:51:28","timeline":{"discoveries":[{"year":1989,"finding":"PfAMA1 (apical membrane antigen 1) is an integral membrane protein located in the apical complex of P. falciparum merozoites and is transported to the merozoite surface near the time of schizont rupture.","method":"Molecular cloning and subcellular localization by immunoelectron microscopy/immunofluorescence","journal":"Molecular and cellular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — original cloning plus direct localization by immunomicroscopy, single lab, foundational finding","pmids":["2701947"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":1990,"finding":"PfAMA1 is localized to the neck region of the rhoptry organelle in P. falciparum merozoites (not the rhoptry body), is Triton X-114 soluble (membrane-associated), and its 80 kDa precursor is immediately processed to a 62 kDa product upon synthesis; it is detectable on the merozoite surface but not in ring-infected erythrocytes.","method":"Immunoelectron microscopy, Triton X-114 phase separation, pulse-chase metabolic labeling, 2D gel electrophoresis, immunoblot","journal":"Experimental parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal biochemical and microscopy methods, single lab","pmids":["2404781"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":1996,"finding":"All 16 conserved cysteine residues of AMA1 are incorporated into 8 intramolecular disulfide bonds that define three nonoverlapping subdomains within the AMA1 ectodomain; six bonds were assigned unequivocally by mass spectrometry and N-terminal sequencing of reduced/non-reduced tryptic digests. The disulfide bond pattern clusters polymorphic sites in subdomains II and III, consistent with immune-selection of conformational epitopes.","method":"Reversed-phase HPLC, N-terminal sequencing, electrospray-ionization mass spectrometry of tryptic digests from baculovirus-expressed P. chabaudi AMA1","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — rigorous biochemical mapping of disulfide bonds using multiple orthogonal methods (MS + sequencing + HPLC), replicated across multiple peptides","pmids":["8910611"],"is_preprint":false,"attribution":[{"species":"Plasmodium chabaudi","strain":""}]},{"year":2000,"finding":"PfAMA1 is essential for blood-stage growth in P. falciparum; attempts to disrupt the Pfama1 gene by knock-out failed, but trans-species complementation with P. chabaudi AMA1 (PcAMA1) restored at least 35% of PfAMA1 function in human red cells, and PcAMA1 expression in P. falciparum increased efficiency of murine erythrocyte invasion.","method":"Homologous recombination targeting, trans-species complementation with transgenic parasites, erythrocyte invasion assay","journal":"Molecular microbiology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis through failed knockout and successful cross-species complementation, multiple invasion assays, replicated findings across constructs","pmids":["11115107"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""},{"species":"Plasmodium chabaudi","strain":""}]},{"year":2001,"finding":"PfAMA1 unprocessed precursor localizes to microneme organelles in intraerythrocytic schizonts; the processed (mature) form independently translocates from micronemes to the merozoite surface, independently of another microneme protein EBA175.","method":"Immunofluorescence, co-localization microscopy of PfAMA1 and EBA175","journal":"Infection and immunity","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct localization imaging with functional consequence (independent translocation), single lab","pmids":["12228305"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2001,"finding":"Anti-PfAMA1 antibodies inhibit invasion of erythrocytes by P. falciparum merozoites; inhibitory antibodies target both conserved and strain-specific epitopes within the ectodomain, with the majority reacting with strain-specific epitopes in domain I (the most polymorphic N-terminal disulfide-bonded domain).","method":"In vitro erythrocyte invasion inhibition assay with rabbit and affinity-purified human antibodies against recombinant 3D7 AMA1 ectodomain","journal":"Infection and immunity","confidence":"High","confidence_rationale":"Tier 2 / Strong — invasion inhibition assay replicated with both rabbit and human antibodies across multiple parasite lines","pmids":["11292751"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":"3D7"}]},{"year":2001,"finding":"PfAMA1 is processed from an 83 kDa precursor (PfAMA1(83)) to a 66 kDa form (PfAMA1(66)) by cleavage at a specific site (removing the N-terminal prosequence/domain I propeptide); PfAMA1(66) selectively translocates to the merozoite surface at about the time of erythrocyte invasion and is then further proteolytically cleaved at one of two alternative sites (between domains II and III, or membrane-proximal), shedding 44 and 48 kDa soluble ectodomain fragments. PfAMA1 is not modified by N-linked oligosaccharides.","method":"Direct microsequencing, mass spectrometric peptide mass fingerprinting, pulse-chase experiments, immunoblot","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct microsequencing and mass spectrometry definitively mapped cleavage sites; multiple complementary biochemical methods","pmids":["11399764"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2003,"finding":"PfAMA1 ectodomain shedding from the merozoite surface occurs via a single cleavage site 29 residues from the predicted transmembrane domain, mediated by the same membrane-bound parasite serine sheddase (PfSUB2) that sheds the MSP-1 complex. Translocation and shedding of PfAMA1 is an actin-independent process.","method":"Mass spectrometric mapping of cleavage products, protease inhibitor studies, cytochalasin D actin inhibition assay","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — conclusive mass spectrometric identification of a single shedding cleavage site, enzyme identity established, actin-independence validated pharmacologically","pmids":["12686561"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2003,"finding":"PfAMA1 is expressed in P. falciparum sporozoites and is lost after invasion of hepatocytes; anti-AMA1 antibodies inhibit sporozoite invasion of hepatocytes. Upon microneme exocytosis, PfAMA1 (like TRAP) relocates to the sporozoite surface and is proteolytically cleaved and shed; serine protease inhibitors block this processing and shedding and inhibit sporozoite infectivity.","method":"Immunofluorescence, invasion inhibition assay with anti-AMA1 antibodies, serine protease inhibitor treatment, Western blot","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct localization, antibody inhibition of invasion, and protease inhibitor studies, single lab, multiple methods","pmids":["14676185"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2003,"finding":"PfAMA1 is translocated within micronemes along subpellicular microtubules from near the nucleus to the merozoite apex during merozoite development, where micronemes dock with rhoptry tips. PfAMA1 antibodies label the peripheries of translocating and mature micronemes but not rhoptries, confirming its micronemal localization.","method":"Immunoelectron microscopy with polyclonal anti-PfAMA1 antibodies on developing schizonts","journal":"Journal of cell science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct localization by immunoelectron microscopy with multiple antibodies, single lab","pmids":["12902400"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2003,"finding":"Invasion-inhibitory IgG antibodies against correctly folded PfAMA1 block proteolytic processing of AMA1 (reduce the 44 and 48 kDa products, increase 66 and 52 kDa forms on merozoites) and prevent circumferential redistribution of AMA1 on the merozoite surface. Monovalent Fab fragments also inhibit invasion and cause accumulation of 66 and 52 kDa forms without cross-linking. Chymostatin and Ca2+ chelators also inhibit breakdown of the 66 kDa form.","method":"In vitro invasion inhibition assay, immunoblot of AMA1 processing intermediates, antibody cross-linking/trapping experiments, Fab fragment preparation","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple complementary in vitro assays including Fab vs IgG comparison, single lab","pmids":["14526103"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2004,"finding":"PfAMA1 mediates the close (junctional) apical attachment of merozoites to erythrocytes and is required for merozoite reorientation; an invasion-inhibitory monoclonal antibody against P. knowlesi AMA1 (MAb R31C2) allows initial long-range contact (12 nm) but prevents merozoite reorientation and subsequent tight junctional apical contact.","method":"Ultrastructural analysis by electron microscopy of P. knowlesi merozoites incubated with inhibitory monoclonal antibody","journal":"Infection and immunity","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct mechanistic ultrastructural analysis at defined invasion step with invasion-blocking antibody, clear phenotypic readout","pmids":["14688092"],"is_preprint":false,"attribution":[{"species":"Plasmodium knowlesi","strain":""}]},{"year":2004,"finding":"Sequence polymorphisms within PfAMA1 (specifically in domain I) directly confer evasion of invasion-inhibitory antibodies; transgenic P. falciparum expressing heterologous AMA1 alleles differ in susceptibility to allele-specific inhibitory antibodies, and exchange of polymorphic domain 1 residues in a chimeric AMA1 affects antibody recognition.","method":"Allelic exchange transgenesis, in vitro invasion inhibition assays with allele-specific antibodies, chimeric AMA1 parasite lines","journal":"Molecular microbiology","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct genetic evidence via allelic exchange and chimeric constructs linked to functional invasion inhibition assays","pmids":["15049818"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2005,"finding":"The crystal structure of PfAMA1 domains I+II reveals two intimately associated PAN domains; domain I contains long loops forming a scaffold for numerous polymorphic residues exclusively on one side of the molecule, surrounding a conserved hydrophobic trough predicted to be the receptor binding pocket.","method":"X-ray crystallography","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1 / Strong — X-ray crystal structure with functional mapping of polymorphic and conserved regions","pmids":["16129835"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2005,"finding":"The crystal structure of the complete ectoplasmic region of AMA1 from P. vivax (three domains) at 1.8 Å resolution shows that domains I and II belong to the PAN motif superfamily implicated in receptor binding; the epitope of an invasion-inhibitory monoclonal antibody specific for P. falciparum AMA1 was mapped and modeled onto the structure, suggesting domain II plays a critical part in receptor binding during invasion.","method":"X-ray crystallography at 1.8 Å, epitope mapping by mutagenesis, modeling","journal":"Science (New York, N.Y.)","confidence":"High","confidence_rationale":"Tier 1 / Strong — high-resolution crystal structure with functional epitope mapping and mutagenesis, multiple orthogonal analyses","pmids":["15731407"],"is_preprint":false,"attribution":[{"species":"Plasmodium vivax","strain":""}]},{"year":2005,"finding":"Domain III of PfAMA1 binds to the erythrocyte membrane protein Kx after trypsin treatment; neither domains I/II nor the full ectodomain bind untreated erythrocytes. Invasion of Kx-null (McLeod) erythrocytes by P. falciparum is significantly reduced, indicating a role for AMA1-Kx interaction in invasion.","method":"CHO-K1 cell surface expression of AMA1 domain constructs, erythrocyte binding assay with trypsin-treated and genetically mutant RBCs, P. falciparum invasion assay with Kx-null erythrocytes","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct binding assay with domain constructs plus genetic validation with Kx-null erythrocytes, single lab","pmids":["15805191"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2005,"finding":"PfAMA1 shedding during erythrocyte invasion goes essentially to completion via a single juxtamembrane sheddase cleavage at Thr517; only the juxtamembrane ectodomain stub is carried into the host cell and remains on the plasma membrane of the intracellular ring-stage parasite. When normal shedding is inhibited, PfAMA1 can be cleaved at an intramembrane rhomboid-like site, and PfAMA1 is susceptible to Drosophila rhomboid-1 cleavage in vitro, but is not normally processed this way.","method":"Mass spectrometry mapping of cleavage products, invasion assay with sheddase inhibitors, Drosophila rhomboid-1 in vitro cleavage assay, immunofluorescence of ring-stage parasites","journal":"Molecular microbiology","confidence":"High","confidence_rationale":"Tier 1 / Strong — definitive biochemical identification of cleavage site, in vitro reconstitution with rhomboid protease, multiple complementary assays","pmids":["16102004"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2005,"finding":"An invasion-inhibitory peptide (R1) from a random phage display library binds the hydrophobic trough of PfAMA1 in a conformation-dependent, strain-specific manner and inhibits merozoite invasion of erythrocytes; NMR solution structure of R1 shows two structured regions (hydrophobic residues 5-10 and polar residues 13-17) that target a binding hot spot also recognized by other invasion-inhibitory peptides and monoclonal antibodies.","method":"Phage display peptide selection, erythrocyte invasion inhibition assay, NMR spectroscopy, competition binding assays","journal":"Infection and immunity","confidence":"High","confidence_rationale":"Tier 1 / Strong — NMR structure determination plus functional invasion assays and competition binding; multiple orthogonal methods","pmids":["16177378"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2006,"finding":"The invasion-inhibitory monoclonal antibody 4G2 epitope lies exclusively within the domain II loop of PfAMA1; purified Fab fragments of 4G2 inhibit invasion more efficiently than the intact mAb, indicating the epitope is within a functionally critical region and invasion inhibition is not due solely to steric effects. The residues critical for 4G2 binding were mapped by alanine-scanning mutagenesis of a synthetic PfAMA1 gene whose function was validated by complementation.","method":"Synthetic gene mutagenesis, functional complementation in P. falciparum, invasion inhibition with Fab vs intact IgG, alanine-scanning epitope mapping","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — epitope fully mapped by mutagenesis, gene validated by complementation, Fab vs IgG functional comparison, multiple orthogonal methods","pmids":["17192270"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2006,"finding":"PfAMA1 co-immunoprecipitates with PfRON4, the P. falciparum homologue of TgRON4, a secreted rhoptry neck protein that forms the moving junction in T. gondii; PfRON4 originates in rhoptry necks, indicating a conserved microneme-rhoptry collaboration at the moving junction across Apicomplexa.","method":"Co-immunoprecipitation, immunoelectron microscopy for PfRON4 localization","journal":"Eukaryotic cell","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — co-immunoprecipitation plus localization, independently replicated by subsequent papers, single method for interaction","pmids":["16835460"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2007,"finding":"An IgNAR single-variable-domain antibody targeting the conserved hydrophobic cleft of PfAMA1 inhibits erythrocyte invasion; co-crystal structures of two IgNAR-AMA1 complexes show extended CDR3 loops penetrating deep into the hydrophobic cleft contacting residues conserved across parasite species.","method":"X-ray co-crystallography, erythrocyte invasion inhibition assay, affinity measurement by surface plasmon resonance, targeted mutagenesis","journal":"Structure (London, England : 1993)","confidence":"High","confidence_rationale":"Tier 1 / Strong — co-crystal structure with functional invasion inhibition assay and mutagenesis of binding residues, multiple orthogonal methods","pmids":["17997971"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2008,"finding":"PfRON2 (a rhoptry neck protein) forms a complex with PfAMA1 and PfRON4 in P. falciparum; PfRON2 transcription peaks at the mature schizont stage and the protein is expressed at the rhoptry neck in merozoites; co-immunoprecipitation shows PfRON2, PfRON4, and PfAMA1 form a complex, conserved from T. gondii. PfRON2 is not a component of the PfRhopH complex.","method":"Co-immunoprecipitation, immunofluorescence, immunoelectron microscopy","journal":"Parasitology international","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — co-IP plus localization data, independently replicated by multiple subsequent papers","pmids":["18952195"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2009,"finding":"The invasion-inhibitory monoclonal antibody 4G2 cannot bind PfAMA1 when PfAMA1 is in a complex with its partner proteins; a single completely conserved PfAMA1 residue Tyr251, lying within a conserved hydrophobic groove adjacent to the 4G2 epitope, is required for complex formation. mAb 4G2 thus inhibits invasion by preventing PfAMA1 from interacting with other components of the invasion complex.","method":"Co-immunoprecipitation, site-directed mutagenesis of PfAMA1, competitive binding assay with mAb 4G2","journal":"PLoS pathogens","confidence":"High","confidence_rationale":"Tier 2 / Strong — mutagenesis of specific residue with functional consequence on complex formation, antibody competition assay, mechanistic insight replicated by subsequent structural studies","pmids":["19165323"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2009,"finding":"The cytoplasmic domain of PfAMA1 is not required for correct trafficking and surface translocation but is essential for AMA1 function during erythrocyte invasion; AMA1 acts at the time of primary contact/moving junction formation upstream of entry. The cytoplasmic domain is phosphorylated, and mutational analysis suggests phosphorylation plays an important role in invasion. Heterologous cytoplasmic domains from P. vivax and P. berghei AMA1 functionally substitute, but those from EBA-175 or Rh2b do not.","method":"Live video microscopy, complementation assay with GFP-tagged AMA1, cytoplasmic domain exchange constructs in transgenic P. falciparum, phosphorylation analysis","journal":"PLoS pathogens","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple transgenic parasite lines with domain swaps, live imaging, functional complementation assay, phosphorylation mapping; multiple orthogonal methods","pmids":["19283086"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2010,"finding":"The invasion-inhibitory peptide R1 binds the PfAMA1 hydrophobic trough and prevents PfAMA1 interaction with the PfRON complex (RON2/RON4/RON5). The AMA1-RON complex forms after merozoite reorientation and engagement of the actomyosin motor but before rhoptry release; this interaction is proposed to be essential for secretion of rhoptry contents necessary for parasitophorous vacuole establishment.","method":"In vitro invasion inhibition assay, co-immunoprecipitation, competitive binding assay with R1 peptide, epistatic ordering by pharmacological inhibitors of invasion steps","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP, peptide competition, and pharmacological ordering of invasion steps; pathway placement, single lab","pmids":["20228060"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2010,"finding":"The cytoplasmic tail of PfAMA1 is phosphorylated at serine 610 by cAMP-dependent protein kinase A (PfPKA); mutation of Ser610 to alanine abolishes in vivo phosphorylation and dramatically impedes erythrocyte invasion.","method":"Mass spectrometry-based phosphorylation mapping, in vivo mutagenesis (Ser610Ala) in transgenic P. falciparum, invasion assay, pharmacological PKA inhibition","journal":"PLoS pathogens","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — site-specific mutagenesis with in vivo phenotype, mass spectrometry phosphosite identification, enzyme (PfPKA) identified, multiple orthogonal assays","pmids":["20532217"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2011,"finding":"Binding of RON2 to the hydrophobic pocket of PfAMA1 is the molecular step that commits P. falciparum merozoites to RBC invasion and triggers junction formation; two conserved disulfide-linked cysteines in the RON2 peptide are critical for binding to the AMA1 pocket. Anti-AMA1 pocket antibodies block both junction formation and parasitophorous vacuole induction, while the RON2 peptide blocks junction formation but not parasitophorous vacuole formation, indicating these are molecularly distinct steps.","method":"Antibody inhibition assays targeting the hydrophobic pocket, AMA1 pocket mutagenesis, invasion inhibition assay with RON2 peptide, electron microscopy of junction formation","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — mutagenesis of AMA1 binding site and RON2 peptide cysteines, antibody competition, functional invasion assays, mechanistic dissection of two distinct invasion steps","pmids":["21788485"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2011,"finding":"In P. berghei, AMA1 is important for merozoite invasion of erythrocytes but is dispensable for sporozoite invasion of hepatocytes (where RON4 acts independently of AMA1). In T. gondii tachyzoites, AMA1 is dispensable for normal RON4 ring and tight junction assembly but enhances tachyzoite apposition and internalization frequency.","method":"Conditional knockout/knockdown in P. berghei, invasion assay (erythrocyte and hepatocyte), genetic and functional analysis in T. gondii","journal":"Cell host & microbe","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic loss-of-function in P. berghei with distinct invasion phenotypes, multiple cell types, comparison across apicomplexan species","pmids":["22177563"],"is_preprint":false,"attribution":[{"species":"Plasmodium berghei","strain":""}]},{"year":2012,"finding":"The crystal structure of PfAMA1 in complex with a peptide from the extracellular region of PfRON2 reveals that the receptor-binding site of PfAMA1 comprises the hydrophobic groove and a region exposed by displacement of the flexible domain II loop. Key contact residues of PfRON2 and PfAMA1 were identified by mutagenesis and abrogated recombinant protein binding. The PfRON2 peptide inhibits erythrocyte invasion regardless of AMA1 polymorphisms. The invasion-inhibitory phage display peptide R1 structurally mimics PfRON2.","method":"X-ray crystallography of AMA1-RON2 peptide complex, alanine-scanning mutagenesis, binding assays with recombinant proteins, erythrocyte invasion inhibition assay","journal":"PLoS pathogens","confidence":"High","confidence_rationale":"Tier 1 / Strong — co-crystal structure plus mutagenesis plus functional invasion assays, multiple orthogonal methods; extensive structural-functional characterization","pmids":["22737069"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2014,"finding":"Conditional DiCre-mediated excision of the Pfama1 gene in P. falciparum results in ~80% decreased AMA1 expression within one intraerythrocytic growth cycle, reduces growth by 40%, and causes a post-invasion defect in sealing of the parasitophorous vacuole; demonstrating AMA1 is essential for merozoite invasion and plays a role in resealing of the red blood cell after invasion.","method":"Conditional knockdown using dimerizable Cre recombinase (DiCre) with loxP-flanked Pfama1 gene, growth assay, invasion efficiency analysis","journal":"Cellular microbiology","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional genetic knockdown with specific quantified invasion and vacuole-sealing phenotype; functionally demonstrates essentiality in P. falciparum","pmids":["24571085"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2014,"finding":"Immunization with a PfAMA1-RON2 peptide complex (but not AMA1 alone) provides complete protection against lethal P. yoelii challenge in mice, and IgG from complex-immunized mice transfers protection; IgG from PfAMA1-RON2-immunized animals shows enhanced invasion inhibition compared with AMA1-alone IgG, associated with a shift in antibody specificity toward loop regions surrounding the RON2 binding site.","method":"Mouse immunization, passive IgG transfer, in vitro invasion inhibition assay, epitope mapping","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — passive transfer of protection, in vitro invasion inhibition, epitope mapping; single lab","pmids":["24958881"],"is_preprint":false,"attribution":[{"species":"Plasmodium yoelii","strain":""}]},{"year":2025,"finding":"The domain II (DII) loop of PfAMA1 plays a critical role in the late-stage binding event with PfRON2; computational simulation and experimental validation identified key amino acid residues in the PfRON2 helix essential for binding in the post-binding/loop-closing stage of the AMA1-RON2 interaction.","method":"Molecular dynamics simulation of DII loop dynamics, experimental validation of key residues by mutagenesis and binding assays","journal":"Chembiochem : a European journal of chemical biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — computational modeling with experimental validation of residue importance in binding, single lab","pmids":["40067319"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2026,"finding":"The endogenous structure of the moving junction basic repeating unit from invasion-stalled P. falciparum parasites is a 1:1:1:1 complex of PfAMA1, PfRON2, PfRON4, and PfRON5 (sailboat-shaped). PfRON2 has two transmembrane helices that anchor the complex in the RBC membrane and display an extracellular handle for PfAMA1 binding; PfAMA1 directly contacts the RBC membrane. PfRON2/4/5 form a large basic platform inside the RBC that electrostatically engages the RBC membrane and inserts seven amphipathic helices into the bilayer, suggesting active host-membrane remodeling.","method":"Cryo-EM structure determination of endogenous moving junction complex purified from invasion-stalled P. falciparum parasites; computational protein design of inhibitory binder","journal":"Cell","confidence":"High","confidence_rationale":"Tier 1 / Strong — endogenous native complex cryo-EM structure with functional validation by designed inhibitor; mechanistically definitive","pmids":["42379167"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"current_model":"PfAMA1 is a type I transmembrane micronemal protein that is processed from an 83 kDa precursor to a 66 kDa form (via removal of an N-terminal prosequence), translocates along subpellicular microtubules to the merozoite apex, and relocates to the merozoite surface at around the time of erythrocyte invasion, where it mediates merozoite reorientation and apical attachment to the host red blood cell; upon surface exposure, its cytoplasmic tail is phosphorylated at Ser610 by PfPKA (essential for function), and its ectodomain interacts via a conserved hydrophobic groove with the extracellular segment of PfRON2 (itself anchored in the RBC membrane as part of a 1:1:1:1 PfAMA1–PfRON2–PfRON4–PfRON5 moving junction complex) to trigger commitment to invasion and tight junction formation, after which the ectodomain is proteolytically shed by a membrane-bound serine sheddase (PfSUB2) at a single juxtamembrane site, and the gene itself is essential for blood-stage parasite survival."},"narrative":{"mechanistic_narrative":"AMA1 (PF3D7_1133400) is a type I integral membrane protein of the apical complex that is essential for blood-stage survival and mediates the apical attachment and reorientation steps of host-cell invasion by Plasmodium merozoites [PMID:2701947, PMID:11115107, PMID:14688092, PMID:24571085]. It matures within micronemes as an 83 kDa precursor that is proteolytically processed to a 66 kDa form (removal of an N-terminal prosequence) and translocates along subpellicular microtubules to the merozoite apex before relocating to the merozoite surface at about the time of erythrocyte invasion [PMID:11399764, PMID:12902400, PMID:2404781]. The ectodomain is folded by eight intramolecular disulfide bonds into three PAN-motif subdomains, with domain I loops presenting polymorphic residues around a conserved hydrophobic groove that forms the receptor-binding pocket [PMID:8910611, PMID:16129835, PMID:15731407]. Through this groove — including the conserved residue Tyr251 and a surface exposed by displacement of the domain II loop — AMA1 binds the extracellular segment of PfRON2, the molecular step that commits merozoites to invasion and triggers tight-junction formation; the endogenous moving junction is a 1:1:1:1 PfAMA1–PfRON2–PfRON4–PfRON5 complex in which AMA1 directly contacts the RBC membrane [PMID:19165323, PMID:22737069, PMID:21788485, PMID:16835460, PMID:18952195, PMID:42379167]. AMA1 function additionally requires phosphorylation of its cytoplasmic tail at Ser610 by cAMP-dependent protein kinase A (PfPKA) [PMID:20532217, PMID:19283086], and following junction engagement the ectodomain is shed essentially to completion by the membrane-bound serine sheddase PfSUB2 at a single juxtamembrane site, leaving only a membrane stub carried into the host cell [PMID:12686561, PMID:16102004]. Because domain I polymorphisms confer escape from invasion-inhibitory antibodies while the RON2-binding pocket remains conserved, AMA1 and the AMA1–RON2 interface are foci of vaccine and inhibitor design [PMID:15049818, PMID:11292751, PMID:22737069, PMID:24958881].","teleology":[{"year":1989,"claim":"Establishing where AMA1 acts required first placing the protein in the cell; its identification as an integral membrane protein of the merozoite apical complex that reaches the surface near schizont rupture defined it as an invasion-stage molecule.","evidence":"Molecular cloning with immunoelectron microscopy and immunofluorescence in P. falciparum","pmids":["2701947","2404781"],"confidence":"Medium","gaps":["Molecular function at the surface not yet defined","Precursor processing enzyme unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":1996,"claim":"Understanding how the ectodomain is organized and why it is antigenically variable required mapping its covalent architecture; assignment of eight disulfide bonds defined three subdomains and showed polymorphic sites cluster into conformational epitopes.","evidence":"MS, N-terminal sequencing and HPLC of baculovirus-expressed P. chabaudi AMA1","pmids":["8910611"],"confidence":"High","gaps":["3D fold not yet resolved","Receptor-binding surface not localized"],"attribution":[{"species":"Plasmodium chabaudi","strain":""}]},{"year":2000,"claim":"Whether AMA1 was dispensable or required was resolved genetically; failure to disrupt the gene combined with partial cross-species complementation established essentiality for blood-stage growth and functional conservation across species.","evidence":"Knockout attempts and trans-species complementation with P. chabaudi AMA1 in P. falciparum, invasion assays","pmids":["11115107"],"confidence":"High","gaps":["Which invasion step AMA1 executes not defined","Molecular partners unidentified"],"attribution":[{"species":"Plasmodium falciparum","strain":""},{"species":"Plasmodium chabaudi","strain":""}]},{"year":2001,"claim":"Linking AMA1 to a defined invasion role required trafficking and processing detail plus functional interference; independent surface translocation of the processed 66 kDa form and antibody-mediated invasion block established AMA1 as a surface-acting invasion effector, with proteolytic maturation and shedding as regulatory events.","evidence":"Immunofluorescence trafficking analysis, microsequencing/MS cleavage-site mapping, and invasion-inhibition assays with anti-3D7 AMA1 antibodies","pmids":["12228305","11399764","11292751"],"confidence":"High","gaps":["Shedding protease not yet identified","Erythrocyte receptor unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2003,"claim":"Defining the physical step AMA1 performs and how it is trafficked required ultrastructure and enzymology; microtubule-guided micronemal delivery, actin-independent surface shedding by the PfSUB2 serine sheddase at a single juxtamembrane site, and antibody evidence that AMA1 governs merozoite reorientation and apical attachment placed AMA1 at the reorientation/junction step.","evidence":"Immunoelectron microscopy, MS cleavage mapping, protease/cytochalasin D inhibitor studies, and inhibitory anti-P. knowlesi AMA1 mAb ultrastructural analysis","pmids":["12902400","12686561","14688092","14676185","14526103"],"confidence":"High","gaps":["Direct receptor/partner at the junction not yet identified","Regulation of shedding timing unclear"],"attribution":[{"species":"Plasmodium falciparum","strain":""},{"species":"Plasmodium knowlesi","strain":""}]},{"year":2005,"claim":"Understanding the antigenic and receptor-binding basis of AMA1 required its atomic structure; crystal structures revealed PAN-domain architecture with polymorphic domain I loops surrounding a conserved hydrophobic trough, allelic exchange showed domain I polymorphisms drive antibody escape, and candidate erythrocyte interactions (domain III–Kx) and shedding-site chemistry were defined.","evidence":"X-ray crystallography of P. falciparum DI+II and P. vivax ectodomain, allelic-exchange transgenics, CHO-based binding/Kx-null invasion assays, MS mapping of the Thr517 shedding site","pmids":["16129835","15731407","15049818","15805191","16102004"],"confidence":"High","gaps":["Physiological ligand of the hydrophobic trough still unknown","Kx interaction not integrated into a mechanistic model"],"attribution":[{"species":"Plasmodium falciparum","strain":""},{"species":"Plasmodium vivax","strain":""}]},{"year":2006,"claim":"Locating the functional inhibitory hotspot required epitope mapping and partner identification; peptide/antibody structures pinpointed the hydrophobic cleft and domain II loop as invasion-critical, and co-immunoprecipitation of PfAMA1 with PfRON4 first tied AMA1 to a conserved rhoptry-neck moving-junction complex.","evidence":"NMR of the R1 peptide, IgNAR and mAb 4G2 epitope mapping/co-crystals with functional invasion assays, and Co-IP with immuno-EM of PfRON4","pmids":["16177378","17997971","17192270","16835460"],"confidence":"High","gaps":["Direct AMA1 partner in the pocket not yet identified (RON4 interaction indirect)","Complex stoichiometry unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2009,"claim":"Determining what the hydrophobic groove actually binds and how AMA1 is activated required residue-level and cytoplasmic-domain dissection; Tyr251 was shown essential for complex formation, the cytoplasmic tail was found dispensable for trafficking but essential and phosphoregulated for invasion, extending AMA1 control beyond the ectodomain.","evidence":"Site-directed mutagenesis with 4G2 competition Co-IP, and cytoplasmic-domain swap/GFP complementation with live imaging in transgenic P. falciparum","pmids":["19165323","19283086"],"confidence":"High","gaps":["Identity of the pocket ligand still not proven to be RON2","Kinase and phosphosite not yet identified"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2011,"claim":"Establishing the causal molecular trigger and its species-specificity required linking pocket occupancy to a defined invasion decision; PfRON2 binding to the AMA1 pocket was shown to commit merozoites to invasion and trigger junction formation, distinct from vacuole induction, while genetics revealed AMA1 is required for erythrocyte but not sporozoite invasion in P. berghei.","evidence":"PfRON2/PfRON4 Co-IP and localization, AMA1-pocket and RON2-cysteine mutagenesis, R1 competition with epistatic ordering, Ser610Ala mutagenesis with PfPKA inhibition, and conditional knockout in P. berghei / T. gondii","pmids":["21788485","20228060","18952195","20532217","22177563"],"confidence":"High","gaps":["Atomic details of the AMA1–RON2 interface not yet resolved","How Ser610 phosphorylation couples to invasion mechanically unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""},{"species":"Plasmodium berghei","strain":""}]},{"year":2014,"claim":"Refining AMA1's function beyond entry required conditional depletion and structure; DiCre excision showed AMA1 is essential for invasion and additionally required for post-invasion sealing of the parasitophorous vacuole, and the AMA1–RON2 co-crystal defined the groove plus domain-II-loop-displacement interface that RON2 (and the mimetic R1) engage.","evidence":"Conditional DiCre knockdown with growth/invasion analysis, and X-ray co-crystallography of the AMA1–RON2 peptide complex with alanine-scanning mutagenesis","pmids":["24571085","22737069"],"confidence":"High","gaps":["Mechanism of vacuole-sealing role not defined","Full native junction architecture not yet resolved"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2026,"claim":"Resolving the assembled junction as it operates required a native structure; cryo-EM of the endogenous 1:1:1:1 PfAMA1–PfRON2–PfRON4–PfRON5 unit from invasion-stalled parasites showed RON2 anchored in the RBC membrane displaying an extracellular handle for AMA1, AMA1 directly contacting the RBC membrane, and a RON2/4/5 platform inserting amphipathic helices into the host bilayer, while MD/mutagenesis refined the late DII-loop-closing binding step.","evidence":"Cryo-EM of endogenous moving-junction complex with computational inhibitor design, and molecular dynamics with mutagenesis/binding validation of the DII loop","pmids":["42379167","40067319"],"confidence":"High","gaps":["Dynamics of AMA1 conformational change during junction traversal not fully resolved","How PfSUB2 shedding is coordinated with the assembled junction unclear"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":null,"claim":"How AMA1 mechanically couples its RON2-engaged ectodomain and Ser610-phosphorylated cytoplasmic tail to the actomyosin motor to drive host-membrane remodeling and vacuole sealing remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structure of the phosphorylated cytoplasmic tail engaged with motor components","Mechanochemical link between junction engagement and force transmission undefined","Molecular basis of the post-invasion vacuole-sealing role unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["PfAMA1-PfRON2-PfRON4-PfRON5 moving junction complex (1:1:1:1) [#32]","PfAMA1-PfRON4 co-immunoprecipitated complex [#19]","PfAMA1-PfRON2-PfRON4 complex [#21]"],"partners":["PFRON2 (RHOPTRY NECK PROTEIN; BINDS AMA1 HYDROPHOBIC GROOVE) [#26, #28, #21, #32, #31]","PFRON4 [#19, #21, #32]","PFRON5 [#32]","PFSUB2 (MEMBRANE-BOUND SERINE SHEDDASE THAT SHEDS THE ECTODOMAIN) [#7]","PFPKA (CAMP-DEPENDENT PROTEIN KINASE A; PHOSPHORYLATES CYTOPLASMIC SER610) [#25]","KX ERYTHROCYTE MEMBRANE PROTEIN (BINDS DOMAIN III AFTER TRYPSIN TREATMENT) [#15]"],"other_free_text":["83 kDa precursor processed to 66 kDa mature form by removal of N-terminal prosequence [#6]","Ectodomain contains 8 disulfide bonds defining three PAN-motif subdomains; polymorphic residues cluster in domain I around a conserved hydrophobic groove/trough [#2, #13, #14]","Ectodomain shed to completion at a single juxtamembrane site (Thr517), leaving a membrane stub carried into the host cell [#16, #7]","Cytoplasmic tail phosphorylated at Ser610; essential for invasion but dispensable for trafficking [#25, #23]","Domain I polymorphisms confer escape from invasion-inhibitory antibodies; RON2-binding pocket conserved [#12, #5]","AMA1-RON2 peptide complex immunization confers protection and shifts antibody specificity toward loops around the RON2 site [#30]","Species divergence: AMA1 required for merozoite (erythrocyte) invasion but dispensable for P. berghei sporozoite invasion of hepatocytes and enhances but is not required for T. gondii junction assembly [#27]"]}},"prefetch_data":{},"corpus_meta":[{"pmid":"11292751","id":"PMC_11292751","title":"Specificity of the protective antibody response to apical membrane antigen 1.","date":"2001","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/11292751","citation_count":273,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"11115107","id":"PMC_11115107","title":"Apical membrane antigen 1 plays a central role in erythrocyte invasion by Plasmodium species.","date":"2000","source":"Molecular microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/11115107","citation_count":266,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1","PcAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"14676185","id":"PMC_14676185","title":"A role for apical membrane antigen 1 during invasion of hepatocytes by Plasmodium falciparum sporozoites.","date":"2003","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/14676185","citation_count":264,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"21788485","id":"PMC_21788485","title":"Binding of Plasmodium merozoite proteins RON2 and AMA1 triggers commitment to invasion.","date":"2011","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/21788485","citation_count":244,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"18226584","id":"PMC_18226584","title":"Apical membrane antigen 1: a malaria vaccine candidate in review.","date":"2008","source":"Trends in parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/18226584","citation_count":232,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"2701947","id":"PMC_2701947","title":"Integral membrane protein located in the apical complex of Plasmodium falciparum.","date":"1989","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/2701947","citation_count":229,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"15908397","id":"PMC_15908397","title":"Phase 1 clinical trial of apical membrane antigen 1: an asexual blood-stage vaccine for Plasmodium falciparum malaria.","date":"2005","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/15908397","citation_count":226,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"12438374","id":"PMC_12438374","title":"In vitro studies with recombinant Plasmodium falciparum apical membrane antigen 1 (AMA1): production and activity of an AMA1 vaccine and generation of a multiallelic response.","date":"2002","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/12438374","citation_count":224,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"9584096","id":"PMC_9584096","title":"Genetic polymorphism and natural selection in the malaria parasite Plasmodium falciparum.","date":"1998","source":"Genetics","url":"https://pubmed.ncbi.nlm.nih.gov/9584096","citation_count":213,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"20228060","id":"PMC_20228060","title":"Interaction between Plasmodium falciparum apical membrane antigen 1 and the rhoptry neck protein complex defines a key step in the erythrocyte invasion process of malaria parasites.","date":"2010","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/20228060","citation_count":213,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"8910611","id":"PMC_8910611","title":"The disulfide bond structure of Plasmodium apical membrane antigen-1.","date":"1996","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/8910611","citation_count":213,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"11514442","id":"PMC_11514442","title":"Strong diversifying selection on domains of the Plasmodium falciparum apical membrane antigen 1 gene.","date":"2001","source":"Genetics","url":"https://pubmed.ncbi.nlm.nih.gov/11514442","citation_count":197,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"8757869","id":"PMC_8757869","title":"Protective immune responses to apical membrane antigen 1 of Plasmodium chabaudi involve recognition of strain-specific epitopes.","date":"1996","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/8757869","citation_count":195,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"18268027","id":"PMC_18268027","title":"Wheat germ cell-free system-based production of malaria proteins for discovery of novel vaccine candidates.","date":"2008","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/18268027","citation_count":182,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"16129835","id":"PMC_16129835","title":"Structure of AMA1 from Plasmodium falciparum reveals a clustering of polymorphisms that surround a conserved hydrophobic pocket.","date":"2005","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/16129835","citation_count":174,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19390585","id":"PMC_19390585","title":"Phase 1/2a study of the malaria vaccine candidate apical membrane antigen-1 (AMA-1) administered in adjuvant system AS01B or AS02A.","date":"2009","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/19390585","citation_count":169,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"15542195","id":"PMC_15542195","title":"Human antibodies to recombinant protein constructs of Plasmodium falciparum Apical Membrane Antigen 1 (AMA1) and their associations with protection from malaria.","date":"2004","source":"Vaccine","url":"https://pubmed.ncbi.nlm.nih.gov/15542195","citation_count":168,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"14688092","id":"PMC_14688092","title":"Apical membrane antigen 1, a major malaria vaccine candidate, mediates the close attachment of invasive merozoites to host red blood cells.","date":"2004","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/14688092","citation_count":168,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"12117958","id":"PMC_12117958","title":"High-level expression of the malaria blood-stage vaccine candidate Plasmodium falciparum apical membrane antigen 1 and induction of antibodies that inhibit erythrocyte invasion.","date":"2002","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/12117958","citation_count":165,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"15731407","id":"PMC_15731407","title":"Crystal structure of the malaria vaccine candidate apical membrane antigen 1.","date":"2005","source":"Science (New York, N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/15731407","citation_count":165,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"7630387","id":"PMC_7630387","title":"Natural selection on Plasmodium surface proteins.","date":"1995","source":"Molecular and biochemical parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/7630387","citation_count":163,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"12438375","id":"PMC_12438375","title":"Vaccination of monkeys with recombinant Plasmodium falciparum apical membrane antigen 1 confers protection against blood-stage malaria.","date":"2002","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/12438375","citation_count":158,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"15049818","id":"PMC_15049818","title":"Allelic polymorphisms in apical membrane antigen-1 are responsible for evasion of antibody-mediated inhibition in Plasmodium falciparum.","date":"2004","source":"Molecular microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/15049818","citation_count":153,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"17598897","id":"PMC_17598897","title":"IgG antibody responses to Plasmodium falciparum merozoite antigens in Kenyan children have a short half-life.","date":"2007","source":"Malaria journal","url":"https://pubmed.ncbi.nlm.nih.gov/17598897","citation_count":152,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"12228305","id":"PMC_12228305","title":"Independent translocation of two micronemal proteins in developing Plasmodium falciparum merozoites.","date":"2002","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/12228305","citation_count":152,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19165323","id":"PMC_19165323","title":"An inhibitory antibody blocks interactions between components of the malarial invasion machinery.","date":"2009","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/19165323","citation_count":140,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"18952195","id":"PMC_18952195","title":"Rhoptry neck protein RON2 forms a complex with microneme protein AMA1 in Plasmodium falciparum merozoites.","date":"2008","source":"Parasitology international","url":"https://pubmed.ncbi.nlm.nih.gov/18952195","citation_count":140,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"11399764","id":"PMC_11399764","title":"Proteolytic processing and primary structure of Plasmodium falciparum apical membrane antigen-1.","date":"2001","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/11399764","citation_count":133,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"22363582","id":"PMC_22363582","title":"Phase Ia clinical evaluation of the safety and immunogenicity of the Plasmodium falciparum blood-stage antigen AMA1 in ChAd63 and MVA vaccine vectors.","date":"2012","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/22363582","citation_count":131,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"16835460","id":"PMC_16835460","title":"Plasmodium falciparum AMA1 binds a rhoptry neck protein homologous to TgRON4, a component of the moving junction in Toxoplasma gondii.","date":"2006","source":"Eukaryotic cell","url":"https://pubmed.ncbi.nlm.nih.gov/16835460","citation_count":127,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1"],"competing_organism_flag":true,"competing_organism_match":"Toxoplasma","competing_organism_only":false},{"pmid":"20553604","id":"PMC_20553604","title":"Using serological measures to monitor changes in malaria transmission in Vanuatu.","date":"2010","source":"Malaria journal","url":"https://pubmed.ncbi.nlm.nih.gov/20553604","citation_count":126,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"12902400","id":"PMC_12902400","title":"Plasmodium falciparum apical membrane antigen 1 (PfAMA-1) is translocated within micronemes along subpellicular microtubules during merozoite development.","date":"2003","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/12902400","citation_count":120,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"18664257","id":"PMC_18664257","title":"Cohort study of the association of antibody levels to AMA1, MSP119, MSP3 and GLURP with protection from clinical malaria in Ghanaian children.","date":"2008","source":"Malaria journal","url":"https://pubmed.ncbi.nlm.nih.gov/18664257","citation_count":116,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"12686561","id":"PMC_12686561","title":"A single malaria merozoite serine protease mediates shedding of multiple surface proteins by juxtamembrane cleavage.","date":"2003","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/12686561","citation_count":116,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"22737069","id":"PMC_22737069","title":"Structural and functional insights into the malaria parasite moving junction complex.","date":"2012","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/22737069","citation_count":115,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"23144611","id":"PMC_23144611","title":"Enhancing blockade of Plasmodium falciparum erythrocyte invasion: assessing combinations of antibodies against PfRH5 and other merozoite antigens.","date":"2012","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/23144611","citation_count":112,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"20532217","id":"PMC_20532217","title":"Protein kinase a dependent phosphorylation of apical membrane antigen 1 plays an important role in erythrocyte invasion by the malaria parasite.","date":"2010","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/20532217","citation_count":112,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19283086","id":"PMC_19283086","title":"Functional analysis of the leading malaria vaccine candidate AMA-1 reveals an essential role for the cytoplasmic domain in the invasion process.","date":"2009","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/19283086","citation_count":112,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"12595459","id":"PMC_12595459","title":"Geographical structure of diversity and differences between symptomatic and asymptomatic infections for Plasmodium falciparum vaccine candidate AMA1.","date":"2003","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/12595459","citation_count":110,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"12011004","id":"PMC_12011004","title":"Purification, characterization, and immunogenicity of the refolded ectodomain of the Plasmodium falciparum apical membrane antigen 1 expressed in Escherichia coli.","date":"2002","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/12011004","citation_count":101,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"22177563","id":"PMC_22177563","title":"Independent roles of apical membrane antigen 1 and rhoptry neck proteins during host cell invasion by apicomplexa.","date":"2011","source":"Cell host & microbe","url":"https://pubmed.ncbi.nlm.nih.gov/22177563","citation_count":101,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"10768987","id":"PMC_10768987","title":"Immunization with parasite-derived apical membrane antigen 1 or passive immunization with a specific monoclonal antibody protects BALB/c mice against lethal Plasmodium yoelii yoelii YM blood-stage infection.","date":"2000","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/10768987","citation_count":99,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"11295182","id":"PMC_11295182","title":"Polymorphism in the gene encoding the apical membrane antigen-1 (AMA-1) of Plasmodium falciparum. X. Asembo Bay Cohort Project.","date":"2001","source":"Molecular and biochemical parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/11295182","citation_count":98,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"2404781","id":"PMC_2404781","title":"Plasmodium falciparum: two antigens of similar size are located in different compartments of the rhoptry.","date":"1990","source":"Experimental parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/2404781","citation_count":97,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"10802318","id":"PMC_10802318","title":"Plasmodium vivax synonymous substitution frequencies, evolution and population structure deduced from diversity in AMA 1 and MSP 1 genes.","date":"2000","source":"Molecular and biochemical parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/10802318","citation_count":97,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PvAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"14526103","id":"PMC_14526103","title":"Invasion-inhibitory antibodies inhibit proteolytic processing of apical membrane antigen 1 of Plasmodium falciparum merozoites.","date":"2003","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/14526103","citation_count":96,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"16177378","id":"PMC_16177378","title":"Binding hot spot for invasion inhibitory molecules on Plasmodium falciparum apical membrane antigen 1.","date":"2005","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/16177378","citation_count":95,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"18698359","id":"PMC_18698359","title":"Phase 1 trial of AMA1-C1/Alhydrogel plus CPG 7909: an asexual blood-stage vaccine for Plasmodium falciparum malaria.","date":"2008","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/18698359","citation_count":94,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"15811655","id":"PMC_15811655","title":"A human phase 1 vaccine clinical trial of the Plasmodium falciparum malaria vaccine candidate apical membrane antigen 1 in Montanide ISA720 adjuvant.","date":"2005","source":"Vaccine","url":"https://pubmed.ncbi.nlm.nih.gov/15811655","citation_count":93,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"18378635","id":"PMC_18378635","title":"A diversity-covering approach to immunization with Plasmodium falciparum apical membrane antigen 1 induces broader allelic recognition and growth inhibition responses in rabbits.","date":"2008","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/18378635","citation_count":93,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"24571085","id":"PMC_24571085","title":"Conditional expression of apical membrane antigen 1 in Plasmodium falciparum shows it is required for erythrocyte invasion by merozoites.","date":"2014","source":"Cellular microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/24571085","citation_count":93,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"17997971","id":"PMC_17997971","title":"Structure of an IgNAR-AMA1 complex: targeting a conserved hydrophobic cleft broadens malarial strain recognition.","date":"2007","source":"Structure (London, England : 1993)","url":"https://pubmed.ncbi.nlm.nih.gov/17997971","citation_count":93,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"26458807","id":"PMC_26458807","title":"Recent advances in recombinant protein-based malaria vaccines.","date":"2015","source":"Vaccine","url":"https://pubmed.ncbi.nlm.nih.gov/26458807","citation_count":92,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"17192270","id":"PMC_17192270","title":"Fine mapping of an epitope recognized by an invasion-inhibitory monoclonal antibody on the malaria vaccine candidate apical membrane antigen 1.","date":"2006","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/17192270","citation_count":92,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"26908756","id":"PMC_26908756","title":"Demonstration of the Blood-Stage Plasmodium falciparum Controlled Human Malaria Infection Model to Assess Efficacy of the P. falciparum Apical Membrane Antigen 1 Vaccine, FMP2.1/AS01.","date":"2016","source":"The Journal of infectious diseases","url":"https://pubmed.ncbi.nlm.nih.gov/26908756","citation_count":89,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"14997552","id":"PMC_14997552","title":"Selection and affinity maturation of IgNAR variable domains targeting Plasmodium falciparum AMA1.","date":"2004","source":"Proteins","url":"https://pubmed.ncbi.nlm.nih.gov/14997552","citation_count":82,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"16154214","id":"PMC_16154214","title":"Structural comparison of apical membrane antigen 1 orthologues and paralogues in apicomplexan parasites.","date":"2005","source":"Molecular and biochemical parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/16154214","citation_count":82,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1","PvAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"11707616","id":"PMC_11707616","title":"Rapid and precise epitope mapping of monoclonal antibodies against Plasmodium falciparum AMA1 by combined phage display of fragments and random peptides.","date":"2001","source":"Protein engineering","url":"https://pubmed.ncbi.nlm.nih.gov/11707616","citation_count":80,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"9864194","id":"PMC_9864194","title":"High-level expression of Plasmodium vivax apical membrane antigen 1 (AMA-1) in Pichia pastoris: strong immunogenicity in Macaca mulatta immunized with P. vivax AMA-1 and adjuvant SBAS2.","date":"1999","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/9864194","citation_count":80,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"17442466","id":"PMC_17442466","title":"Phase I dose escalation safety and immunogenicity trial of Plasmodium falciparum apical membrane protein (AMA-1) FMP2.1, adjuvanted with AS02A, in malaria-naïve adults at the Walter Reed Army Institute of Research.","date":"2007","source":"Vaccine","url":"https://pubmed.ncbi.nlm.nih.gov/17442466","citation_count":80,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"18515425","id":"PMC_18515425","title":"Population structure of the genes encoding the polymorphic Plasmodium falciparum apical membrane antigen 1: implications for vaccine design.","date":"2008","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/18515425","citation_count":80,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"24958881","id":"PMC_24958881","title":"Immunization with a functional protein complex required for erythrocyte invasion protects against lethal malaria.","date":"2014","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/24958881","citation_count":79,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"12874357","id":"PMC_12874357","title":"Induction of parasite growth-inhibitory antibodies by a virosomal formulation of a peptidomimetic of loop I from domain III of Plasmodium falciparum apical membrane antigen 1.","date":"2003","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/12874357","citation_count":79,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19093004","id":"PMC_19093004","title":"Safety and immunogenicity of a recombinant Plasmodium falciparum AMA1 malaria vaccine adjuvanted with Alhydrogel, Montanide ISA 720 or AS02.","date":"2008","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/19093004","citation_count":78,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"16102004","id":"PMC_16102004","title":"Distinct mechanisms govern proteolytic shedding of a key invasion protein in apicomplexan pathogens.","date":"2005","source":"Molecular microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/16102004","citation_count":78,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"15710439","id":"PMC_15710439","title":"Antibody response of naturally infected individuals to recombinant Plasmodium vivax apical membrane antigen-1.","date":"2004","source":"International journal for parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/15710439","citation_count":76,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PvAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19997632","id":"PMC_19997632","title":"High antibody titer against apical membrane antigen-1 is required to protect against malaria in the Aotus model.","date":"2009","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/19997632","citation_count":76,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"24385910","id":"PMC_24385910","title":"Overcoming antigenic diversity by enhancing the immunogenicity of conserved epitopes on the malaria vaccine candidate apical membrane antigen-1.","date":"2013","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/24385910","citation_count":73,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"20224778","id":"PMC_20224778","title":"Plasmodium vivax: induction of CD4+CD25+FoxP3+ regulatory T cells during infection are directly associated with level of circulating parasites.","date":"2010","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/20224778","citation_count":71,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PvAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"10960173","id":"PMC_10960173","title":"Molecular characterisation of Plasmodium reichenowi apical membrane antigen-1 (AMA-1), comparison with P. falciparum AMA-1, and antibody-mediated inhibition of red cell invasion.","date":"2000","source":"Molecular and biochemical parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/10960173","citation_count":70,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19439523","id":"PMC_19439523","title":"Anti-apical-membrane-antigen-1 antibody is more effective than anti-42-kilodalton-merozoite-surface-protein-1 antibody in inhibiting plasmodium falciparum growth, as determined by the in vitro growth inhibition assay.","date":"2009","source":"Clinical and vaccine immunology : CVI","url":"https://pubmed.ncbi.nlm.nih.gov/19439523","citation_count":69,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"15618180","id":"PMC_15618180","title":"Allele specificity of naturally acquired antibody responses against Plasmodium falciparum apical membrane antigen 1.","date":"2005","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/15618180","citation_count":68,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"25199532","id":"PMC_25199532","title":"Immunological markers of Plasmodium vivax exposure and immunity: a systematic review and meta-analysis.","date":"2014","source":"BMC medicine","url":"https://pubmed.ncbi.nlm.nih.gov/25199532","citation_count":67,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PvAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"15805191","id":"PMC_15805191","title":"Domain III of Plasmodium falciparum apical membrane antigen 1 binds to the erythrocyte membrane protein Kx.","date":"2005","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/15805191","citation_count":67,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19956619","id":"PMC_19956619","title":"Humoral immune response to mixed PfAMA1 alleles; multivalent PfAMA1 vaccines induce broad specificity.","date":"2009","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/19956619","citation_count":65,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"11500430","id":"PMC_11500430","title":"Multistage multiantigen heterologous prime boost vaccine for Plasmodium knowlesi malaria provides partial protection in rhesus macaques.","date":"2001","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/11500430","citation_count":65,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PkAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"17330398","id":"PMC_17330398","title":"Malaria vaccines: are we getting closer?","date":"2007","source":"Current opinion in molecular therapeutics","url":"https://pubmed.ncbi.nlm.nih.gov/17330398","citation_count":63,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19874925","id":"PMC_19874925","title":"A randomized and controlled Phase 1 study of the safety and immunogenicity of the AMA1-C1/Alhydrogel + CPG 7909 vaccine for Plasmodium falciparum malaria in semi-immune Malian adults.","date":"2009","source":"Vaccine","url":"https://pubmed.ncbi.nlm.nih.gov/19874925","citation_count":62,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"42115168","id":"PMC_42115168","title":"Continental-scale genomic surveillance of Plasmodium falciparum malaria across sub-Saharan Africa with rapid nanopore sequencing.","date":"2026","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/42115168","citation_count":2,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"41128014","id":"PMC_41128014","title":"Extreme Genetic Diversity and Signatures of Balancing Selection in Plasmodium vivax Blood-Stage Antigens.","date":"2026","source":"The Journal of infectious diseases","url":"https://pubmed.ncbi.nlm.nih.gov/41128014","citation_count":2,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"42504823","id":"PMC_42504823","title":"An abundant merozoite surface protein of Plasmodium falciparum modulates susceptibility to inhibitory antibodies.","date":"2026","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/42504823","citation_count":1,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"42405907","id":"PMC_42405907","title":"Immunodominant B-cell epitopes for precision surveillance of Plasmodium vivax malaria.","date":"2026","source":"Emerging microbes & infections","url":"https://pubmed.ncbi.nlm.nih.gov/42405907","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"41776459","id":"PMC_41776459","title":"Genetic polymorphism and natural selection of apical membrane antigen-1 in Plasmodium malariae isolated from Vietnam.","date":"2026","source":"BMC infectious diseases","url":"https://pubmed.ncbi.nlm.nih.gov/41776459","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"42270857","id":"PMC_42270857","title":"Comparison of techniques and markers to distinguish Plasmodium falciparum recrudescence from new infection in Rwanda.","date":"2026","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/42270857","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"42379167","id":"PMC_42379167","title":"Structural basis for host membrane binding and remodeling by invading malaria parasites.","date":"2026","source":"Cell","url":"https://pubmed.ncbi.nlm.nih.gov/42379167","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"41923211","id":"PMC_41923211","title":"Distribution of Plasmodium falciparum apical membrane antigen-1 cluster one loop haplotypes and their association with malaria symptoms in Bandiagara, Mali.","date":"2026","source":"BMC infectious diseases","url":"https://pubmed.ncbi.nlm.nih.gov/41923211","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["apical membrane antigen 1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"41804297","id":"PMC_41804297","title":"Synthesis and Characterization of Di- and Tetrapropargyl Derivatives of (+)-Catechin: Evaluation of Their Potential Antimalarial Activity Through In Vitro and In Silico Approaches.","date":"2026","source":"Chemistry & biodiversity","url":"https://pubmed.ncbi.nlm.nih.gov/41804297","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"42023758","id":"PMC_42023758","title":"Life Course Malaria Exposure and SARS-CoV-2 Seroepidemiology in Ugandan Adolescents: A Longitudinal Study Nested in a Birth Cohort.","date":"2026","source":"Tropical medicine & international health : TM & IH","url":"https://pubmed.ncbi.nlm.nih.gov/42023758","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"41893415","id":"PMC_41893415","title":"Cytokine-Driven Immune Phenotypes at Delivery as Indicators of Malaria Infection Among Primigravidae in Burkina Faso: An Exploratory Analysis.","date":"2026","source":"Tropical medicine and infectious disease","url":"https://pubmed.ncbi.nlm.nih.gov/41893415","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"42507702","id":"PMC_42507702","title":"Reconstruction of historical malaria transmission in Senegal using multiplex serocatalytic models.","date":"2026","source":"PLoS computational biology","url":"https://pubmed.ncbi.nlm.nih.gov/42507702","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"40287078","id":"PMC_40287078","title":"Plasmodium falciparum genetic diversity and multiplicity of infection in northern and southern Ghana assessed by amplicon sequencing.","date":"2025","source":"Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases","url":"https://pubmed.ncbi.nlm.nih.gov/40287078","citation_count":2,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"40034395","id":"PMC_40034395","title":"Serology reveals comparable patterns in the transmission intensities of Plasmodium falciparum and Plasmodium vivax in Langkat district, North Sumatera Province, Indonesia.","date":"2025","source":"Frontiers in cellular and infection microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/40034395","citation_count":2,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1","PvAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"41082812","id":"PMC_41082812","title":"Immunogenicity of HLA-restricted peptide vaccine candidates delivered by self-assembling protein nanoparticle (SAPN) technology.","date":"2025","source":"Vaccine","url":"https://pubmed.ncbi.nlm.nih.gov/41082812","citation_count":1,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1","PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"40067319","id":"PMC_40067319","title":"A Cryptic Loop that Modulates Protein-Protein Interaction: Implications in PfAMA1-PfRON2 Late-stage Binding Event.","date":"2025","source":"Chembiochem : a European journal of chemical biology","url":"https://pubmed.ncbi.nlm.nih.gov/40067319","citation_count":1,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"40102442","id":"PMC_40102442","title":"Functionality of Toxoplasma gondii antibodies in a population of Beninese pregnant women exposed to malaria.","date":"2025","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/40102442","citation_count":1,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfAMA1"],"competing_organism_flag":true,"competing_organism_match":"Toxoplasma","competing_organism_only":true},{"pmid":"40672955","id":"PMC_40672955","title":"Development of high affinity antibodies to Plasmodium falciparum merozoite and sporozoite antigens during infancy and adulthood.","date":"2025","source":"Frontiers in immunology","url":"https://pubmed.ncbi.nlm.nih.gov/40672955","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"41135800","id":"PMC_41135800","title":"Plasmodium falciparum Liver Stage Antigen 3 plays a role in completing the final stages of merozoite invasion of red blood cells.","date":"2025","source":"International journal for parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/41135800","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"40268600","id":"PMC_40268600","title":"Holding hands to halt malaria: stronger together through heterotypic antibody interactions.","date":"2025","source":"Trends in parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/40268600","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["AMA1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":52385,"output_tokens":9496,"usd":0.149798,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":18112,"output_tokens":5802,"usd":0.117805,"stage2_stop_reason":"end_turn"},"total_usd":0.267603,"stage1_batch_id":"msgbatch_01DisAaTypwmC8QwdMBuePHo","stage2_batch_id":"msgbatch_0184zxZTqxiEfdYYfPMfkqjb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1989,\n      \"finding\": \"PfAMA1 (apical membrane antigen 1) is an integral membrane protein located in the apical complex of P. falciparum merozoites and is transported to the merozoite surface near the time of schizont rupture.\",\n      \"method\": \"Molecular cloning and subcellular localization by immunoelectron microscopy/immunofluorescence\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — original cloning plus direct localization by immunomicroscopy, single lab, foundational finding\",\n      \"pmids\": [\"2701947\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 1990,\n      \"finding\": \"PfAMA1 is localized to the neck region of the rhoptry organelle in P. falciparum merozoites (not the rhoptry body), is Triton X-114 soluble (membrane-associated), and its 80 kDa precursor is immediately processed to a 62 kDa product upon synthesis; it is detectable on the merozoite surface but not in ring-infected erythrocytes.\",\n      \"method\": \"Immunoelectron microscopy, Triton X-114 phase separation, pulse-chase metabolic labeling, 2D gel electrophoresis, immunoblot\",\n      \"journal\": \"Experimental parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal biochemical and microscopy methods, single lab\",\n      \"pmids\": [\"2404781\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"All 16 conserved cysteine residues of AMA1 are incorporated into 8 intramolecular disulfide bonds that define three nonoverlapping subdomains within the AMA1 ectodomain; six bonds were assigned unequivocally by mass spectrometry and N-terminal sequencing of reduced/non-reduced tryptic digests. The disulfide bond pattern clusters polymorphic sites in subdomains II and III, consistent with immune-selection of conformational epitopes.\",\n      \"method\": \"Reversed-phase HPLC, N-terminal sequencing, electrospray-ionization mass spectrometry of tryptic digests from baculovirus-expressed P. chabaudi AMA1\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — rigorous biochemical mapping of disulfide bonds using multiple orthogonal methods (MS + sequencing + HPLC), replicated across multiple peptides\",\n      \"pmids\": [\"8910611\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium chabaudi\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"PfAMA1 is essential for blood-stage growth in P. falciparum; attempts to disrupt the Pfama1 gene by knock-out failed, but trans-species complementation with P. chabaudi AMA1 (PcAMA1) restored at least 35% of PfAMA1 function in human red cells, and PcAMA1 expression in P. falciparum increased efficiency of murine erythrocyte invasion.\",\n      \"method\": \"Homologous recombination targeting, trans-species complementation with transgenic parasites, erythrocyte invasion assay\",\n      \"journal\": \"Molecular microbiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis through failed knockout and successful cross-species complementation, multiple invasion assays, replicated findings across constructs\",\n      \"pmids\": [\"11115107\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}, {\"species\": \"Plasmodium chabaudi\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"PfAMA1 unprocessed precursor localizes to microneme organelles in intraerythrocytic schizonts; the processed (mature) form independently translocates from micronemes to the merozoite surface, independently of another microneme protein EBA175.\",\n      \"method\": \"Immunofluorescence, co-localization microscopy of PfAMA1 and EBA175\",\n      \"journal\": \"Infection and immunity\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization imaging with functional consequence (independent translocation), single lab\",\n      \"pmids\": [\"12228305\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"Anti-PfAMA1 antibodies inhibit invasion of erythrocytes by P. falciparum merozoites; inhibitory antibodies target both conserved and strain-specific epitopes within the ectodomain, with the majority reacting with strain-specific epitopes in domain I (the most polymorphic N-terminal disulfide-bonded domain).\",\n      \"method\": \"In vitro erythrocyte invasion inhibition assay with rabbit and affinity-purified human antibodies against recombinant 3D7 AMA1 ectodomain\",\n      \"journal\": \"Infection and immunity\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — invasion inhibition assay replicated with both rabbit and human antibodies across multiple parasite lines\",\n      \"pmids\": [\"11292751\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"3D7\"}]\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"PfAMA1 is processed from an 83 kDa precursor (PfAMA1(83)) to a 66 kDa form (PfAMA1(66)) by cleavage at a specific site (removing the N-terminal prosequence/domain I propeptide); PfAMA1(66) selectively translocates to the merozoite surface at about the time of erythrocyte invasion and is then further proteolytically cleaved at one of two alternative sites (between domains II and III, or membrane-proximal), shedding 44 and 48 kDa soluble ectodomain fragments. PfAMA1 is not modified by N-linked oligosaccharides.\",\n      \"method\": \"Direct microsequencing, mass spectrometric peptide mass fingerprinting, pulse-chase experiments, immunoblot\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct microsequencing and mass spectrometry definitively mapped cleavage sites; multiple complementary biochemical methods\",\n      \"pmids\": [\"11399764\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"PfAMA1 ectodomain shedding from the merozoite surface occurs via a single cleavage site 29 residues from the predicted transmembrane domain, mediated by the same membrane-bound parasite serine sheddase (PfSUB2) that sheds the MSP-1 complex. Translocation and shedding of PfAMA1 is an actin-independent process.\",\n      \"method\": \"Mass spectrometric mapping of cleavage products, protease inhibitor studies, cytochalasin D actin inhibition assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — conclusive mass spectrometric identification of a single shedding cleavage site, enzyme identity established, actin-independence validated pharmacologically\",\n      \"pmids\": [\"12686561\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"PfAMA1 is expressed in P. falciparum sporozoites and is lost after invasion of hepatocytes; anti-AMA1 antibodies inhibit sporozoite invasion of hepatocytes. Upon microneme exocytosis, PfAMA1 (like TRAP) relocates to the sporozoite surface and is proteolytically cleaved and shed; serine protease inhibitors block this processing and shedding and inhibit sporozoite infectivity.\",\n      \"method\": \"Immunofluorescence, invasion inhibition assay with anti-AMA1 antibodies, serine protease inhibitor treatment, Western blot\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization, antibody inhibition of invasion, and protease inhibitor studies, single lab, multiple methods\",\n      \"pmids\": [\"14676185\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"PfAMA1 is translocated within micronemes along subpellicular microtubules from near the nucleus to the merozoite apex during merozoite development, where micronemes dock with rhoptry tips. PfAMA1 antibodies label the peripheries of translocating and mature micronemes but not rhoptries, confirming its micronemal localization.\",\n      \"method\": \"Immunoelectron microscopy with polyclonal anti-PfAMA1 antibodies on developing schizonts\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization by immunoelectron microscopy with multiple antibodies, single lab\",\n      \"pmids\": [\"12902400\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Invasion-inhibitory IgG antibodies against correctly folded PfAMA1 block proteolytic processing of AMA1 (reduce the 44 and 48 kDa products, increase 66 and 52 kDa forms on merozoites) and prevent circumferential redistribution of AMA1 on the merozoite surface. Monovalent Fab fragments also inhibit invasion and cause accumulation of 66 and 52 kDa forms without cross-linking. Chymostatin and Ca2+ chelators also inhibit breakdown of the 66 kDa form.\",\n      \"method\": \"In vitro invasion inhibition assay, immunoblot of AMA1 processing intermediates, antibody cross-linking/trapping experiments, Fab fragment preparation\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple complementary in vitro assays including Fab vs IgG comparison, single lab\",\n      \"pmids\": [\"14526103\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"PfAMA1 mediates the close (junctional) apical attachment of merozoites to erythrocytes and is required for merozoite reorientation; an invasion-inhibitory monoclonal antibody against P. knowlesi AMA1 (MAb R31C2) allows initial long-range contact (12 nm) but prevents merozoite reorientation and subsequent tight junctional apical contact.\",\n      \"method\": \"Ultrastructural analysis by electron microscopy of P. knowlesi merozoites incubated with inhibitory monoclonal antibody\",\n      \"journal\": \"Infection and immunity\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct mechanistic ultrastructural analysis at defined invasion step with invasion-blocking antibody, clear phenotypic readout\",\n      \"pmids\": [\"14688092\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium knowlesi\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"Sequence polymorphisms within PfAMA1 (specifically in domain I) directly confer evasion of invasion-inhibitory antibodies; transgenic P. falciparum expressing heterologous AMA1 alleles differ in susceptibility to allele-specific inhibitory antibodies, and exchange of polymorphic domain 1 residues in a chimeric AMA1 affects antibody recognition.\",\n      \"method\": \"Allelic exchange transgenesis, in vitro invasion inhibition assays with allele-specific antibodies, chimeric AMA1 parasite lines\",\n      \"journal\": \"Molecular microbiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct genetic evidence via allelic exchange and chimeric constructs linked to functional invasion inhibition assays\",\n      \"pmids\": [\"15049818\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"The crystal structure of PfAMA1 domains I+II reveals two intimately associated PAN domains; domain I contains long loops forming a scaffold for numerous polymorphic residues exclusively on one side of the molecule, surrounding a conserved hydrophobic trough predicted to be the receptor binding pocket.\",\n      \"method\": \"X-ray crystallography\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — X-ray crystal structure with functional mapping of polymorphic and conserved regions\",\n      \"pmids\": [\"16129835\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"The crystal structure of the complete ectoplasmic region of AMA1 from P. vivax (three domains) at 1.8 Å resolution shows that domains I and II belong to the PAN motif superfamily implicated in receptor binding; the epitope of an invasion-inhibitory monoclonal antibody specific for P. falciparum AMA1 was mapped and modeled onto the structure, suggesting domain II plays a critical part in receptor binding during invasion.\",\n      \"method\": \"X-ray crystallography at 1.8 Å, epitope mapping by mutagenesis, modeling\",\n      \"journal\": \"Science (New York, N.Y.)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — high-resolution crystal structure with functional epitope mapping and mutagenesis, multiple orthogonal analyses\",\n      \"pmids\": [\"15731407\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium vivax\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Domain III of PfAMA1 binds to the erythrocyte membrane protein Kx after trypsin treatment; neither domains I/II nor the full ectodomain bind untreated erythrocytes. Invasion of Kx-null (McLeod) erythrocytes by P. falciparum is significantly reduced, indicating a role for AMA1-Kx interaction in invasion.\",\n      \"method\": \"CHO-K1 cell surface expression of AMA1 domain constructs, erythrocyte binding assay with trypsin-treated and genetically mutant RBCs, P. falciparum invasion assay with Kx-null erythrocytes\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct binding assay with domain constructs plus genetic validation with Kx-null erythrocytes, single lab\",\n      \"pmids\": [\"15805191\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"PfAMA1 shedding during erythrocyte invasion goes essentially to completion via a single juxtamembrane sheddase cleavage at Thr517; only the juxtamembrane ectodomain stub is carried into the host cell and remains on the plasma membrane of the intracellular ring-stage parasite. When normal shedding is inhibited, PfAMA1 can be cleaved at an intramembrane rhomboid-like site, and PfAMA1 is susceptible to Drosophila rhomboid-1 cleavage in vitro, but is not normally processed this way.\",\n      \"method\": \"Mass spectrometry mapping of cleavage products, invasion assay with sheddase inhibitors, Drosophila rhomboid-1 in vitro cleavage assay, immunofluorescence of ring-stage parasites\",\n      \"journal\": \"Molecular microbiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — definitive biochemical identification of cleavage site, in vitro reconstitution with rhomboid protease, multiple complementary assays\",\n      \"pmids\": [\"16102004\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"An invasion-inhibitory peptide (R1) from a random phage display library binds the hydrophobic trough of PfAMA1 in a conformation-dependent, strain-specific manner and inhibits merozoite invasion of erythrocytes; NMR solution structure of R1 shows two structured regions (hydrophobic residues 5-10 and polar residues 13-17) that target a binding hot spot also recognized by other invasion-inhibitory peptides and monoclonal antibodies.\",\n      \"method\": \"Phage display peptide selection, erythrocyte invasion inhibition assay, NMR spectroscopy, competition binding assays\",\n      \"journal\": \"Infection and immunity\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — NMR structure determination plus functional invasion assays and competition binding; multiple orthogonal methods\",\n      \"pmids\": [\"16177378\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"The invasion-inhibitory monoclonal antibody 4G2 epitope lies exclusively within the domain II loop of PfAMA1; purified Fab fragments of 4G2 inhibit invasion more efficiently than the intact mAb, indicating the epitope is within a functionally critical region and invasion inhibition is not due solely to steric effects. The residues critical for 4G2 binding were mapped by alanine-scanning mutagenesis of a synthetic PfAMA1 gene whose function was validated by complementation.\",\n      \"method\": \"Synthetic gene mutagenesis, functional complementation in P. falciparum, invasion inhibition with Fab vs intact IgG, alanine-scanning epitope mapping\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — epitope fully mapped by mutagenesis, gene validated by complementation, Fab vs IgG functional comparison, multiple orthogonal methods\",\n      \"pmids\": [\"17192270\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"PfAMA1 co-immunoprecipitates with PfRON4, the P. falciparum homologue of TgRON4, a secreted rhoptry neck protein that forms the moving junction in T. gondii; PfRON4 originates in rhoptry necks, indicating a conserved microneme-rhoptry collaboration at the moving junction across Apicomplexa.\",\n      \"method\": \"Co-immunoprecipitation, immunoelectron microscopy for PfRON4 localization\",\n      \"journal\": \"Eukaryotic cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — co-immunoprecipitation plus localization, independently replicated by subsequent papers, single method for interaction\",\n      \"pmids\": [\"16835460\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"An IgNAR single-variable-domain antibody targeting the conserved hydrophobic cleft of PfAMA1 inhibits erythrocyte invasion; co-crystal structures of two IgNAR-AMA1 complexes show extended CDR3 loops penetrating deep into the hydrophobic cleft contacting residues conserved across parasite species.\",\n      \"method\": \"X-ray co-crystallography, erythrocyte invasion inhibition assay, affinity measurement by surface plasmon resonance, targeted mutagenesis\",\n      \"journal\": \"Structure (London, England : 1993)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — co-crystal structure with functional invasion inhibition assay and mutagenesis of binding residues, multiple orthogonal methods\",\n      \"pmids\": [\"17997971\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"PfRON2 (a rhoptry neck protein) forms a complex with PfAMA1 and PfRON4 in P. falciparum; PfRON2 transcription peaks at the mature schizont stage and the protein is expressed at the rhoptry neck in merozoites; co-immunoprecipitation shows PfRON2, PfRON4, and PfAMA1 form a complex, conserved from T. gondii. PfRON2 is not a component of the PfRhopH complex.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescence, immunoelectron microscopy\",\n      \"journal\": \"Parasitology international\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — co-IP plus localization data, independently replicated by multiple subsequent papers\",\n      \"pmids\": [\"18952195\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"The invasion-inhibitory monoclonal antibody 4G2 cannot bind PfAMA1 when PfAMA1 is in a complex with its partner proteins; a single completely conserved PfAMA1 residue Tyr251, lying within a conserved hydrophobic groove adjacent to the 4G2 epitope, is required for complex formation. mAb 4G2 thus inhibits invasion by preventing PfAMA1 from interacting with other components of the invasion complex.\",\n      \"method\": \"Co-immunoprecipitation, site-directed mutagenesis of PfAMA1, competitive binding assay with mAb 4G2\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — mutagenesis of specific residue with functional consequence on complex formation, antibody competition assay, mechanistic insight replicated by subsequent structural studies\",\n      \"pmids\": [\"19165323\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"The cytoplasmic domain of PfAMA1 is not required for correct trafficking and surface translocation but is essential for AMA1 function during erythrocyte invasion; AMA1 acts at the time of primary contact/moving junction formation upstream of entry. The cytoplasmic domain is phosphorylated, and mutational analysis suggests phosphorylation plays an important role in invasion. Heterologous cytoplasmic domains from P. vivax and P. berghei AMA1 functionally substitute, but those from EBA-175 or Rh2b do not.\",\n      \"method\": \"Live video microscopy, complementation assay with GFP-tagged AMA1, cytoplasmic domain exchange constructs in transgenic P. falciparum, phosphorylation analysis\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple transgenic parasite lines with domain swaps, live imaging, functional complementation assay, phosphorylation mapping; multiple orthogonal methods\",\n      \"pmids\": [\"19283086\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"The invasion-inhibitory peptide R1 binds the PfAMA1 hydrophobic trough and prevents PfAMA1 interaction with the PfRON complex (RON2/RON4/RON5). The AMA1-RON complex forms after merozoite reorientation and engagement of the actomyosin motor but before rhoptry release; this interaction is proposed to be essential for secretion of rhoptry contents necessary for parasitophorous vacuole establishment.\",\n      \"method\": \"In vitro invasion inhibition assay, co-immunoprecipitation, competitive binding assay with R1 peptide, epistatic ordering by pharmacological inhibitors of invasion steps\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP, peptide competition, and pharmacological ordering of invasion steps; pathway placement, single lab\",\n      \"pmids\": [\"20228060\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"The cytoplasmic tail of PfAMA1 is phosphorylated at serine 610 by cAMP-dependent protein kinase A (PfPKA); mutation of Ser610 to alanine abolishes in vivo phosphorylation and dramatically impedes erythrocyte invasion.\",\n      \"method\": \"Mass spectrometry-based phosphorylation mapping, in vivo mutagenesis (Ser610Ala) in transgenic P. falciparum, invasion assay, pharmacological PKA inhibition\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — site-specific mutagenesis with in vivo phenotype, mass spectrometry phosphosite identification, enzyme (PfPKA) identified, multiple orthogonal assays\",\n      \"pmids\": [\"20532217\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Binding of RON2 to the hydrophobic pocket of PfAMA1 is the molecular step that commits P. falciparum merozoites to RBC invasion and triggers junction formation; two conserved disulfide-linked cysteines in the RON2 peptide are critical for binding to the AMA1 pocket. Anti-AMA1 pocket antibodies block both junction formation and parasitophorous vacuole induction, while the RON2 peptide blocks junction formation but not parasitophorous vacuole formation, indicating these are molecularly distinct steps.\",\n      \"method\": \"Antibody inhibition assays targeting the hydrophobic pocket, AMA1 pocket mutagenesis, invasion inhibition assay with RON2 peptide, electron microscopy of junction formation\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — mutagenesis of AMA1 binding site and RON2 peptide cysteines, antibody competition, functional invasion assays, mechanistic dissection of two distinct invasion steps\",\n      \"pmids\": [\"21788485\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"In P. berghei, AMA1 is important for merozoite invasion of erythrocytes but is dispensable for sporozoite invasion of hepatocytes (where RON4 acts independently of AMA1). In T. gondii tachyzoites, AMA1 is dispensable for normal RON4 ring and tight junction assembly but enhances tachyzoite apposition and internalization frequency.\",\n      \"method\": \"Conditional knockout/knockdown in P. berghei, invasion assay (erythrocyte and hepatocyte), genetic and functional analysis in T. gondii\",\n      \"journal\": \"Cell host & microbe\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic loss-of-function in P. berghei with distinct invasion phenotypes, multiple cell types, comparison across apicomplexan species\",\n      \"pmids\": [\"22177563\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium berghei\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"The crystal structure of PfAMA1 in complex with a peptide from the extracellular region of PfRON2 reveals that the receptor-binding site of PfAMA1 comprises the hydrophobic groove and a region exposed by displacement of the flexible domain II loop. Key contact residues of PfRON2 and PfAMA1 were identified by mutagenesis and abrogated recombinant protein binding. The PfRON2 peptide inhibits erythrocyte invasion regardless of AMA1 polymorphisms. The invasion-inhibitory phage display peptide R1 structurally mimics PfRON2.\",\n      \"method\": \"X-ray crystallography of AMA1-RON2 peptide complex, alanine-scanning mutagenesis, binding assays with recombinant proteins, erythrocyte invasion inhibition assay\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — co-crystal structure plus mutagenesis plus functional invasion assays, multiple orthogonal methods; extensive structural-functional characterization\",\n      \"pmids\": [\"22737069\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Conditional DiCre-mediated excision of the Pfama1 gene in P. falciparum results in ~80% decreased AMA1 expression within one intraerythrocytic growth cycle, reduces growth by 40%, and causes a post-invasion defect in sealing of the parasitophorous vacuole; demonstrating AMA1 is essential for merozoite invasion and plays a role in resealing of the red blood cell after invasion.\",\n      \"method\": \"Conditional knockdown using dimerizable Cre recombinase (DiCre) with loxP-flanked Pfama1 gene, growth assay, invasion efficiency analysis\",\n      \"journal\": \"Cellular microbiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional genetic knockdown with specific quantified invasion and vacuole-sealing phenotype; functionally demonstrates essentiality in P. falciparum\",\n      \"pmids\": [\"24571085\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Immunization with a PfAMA1-RON2 peptide complex (but not AMA1 alone) provides complete protection against lethal P. yoelii challenge in mice, and IgG from complex-immunized mice transfers protection; IgG from PfAMA1-RON2-immunized animals shows enhanced invasion inhibition compared with AMA1-alone IgG, associated with a shift in antibody specificity toward loop regions surrounding the RON2 binding site.\",\n      \"method\": \"Mouse immunization, passive IgG transfer, in vitro invasion inhibition assay, epitope mapping\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — passive transfer of protection, in vitro invasion inhibition, epitope mapping; single lab\",\n      \"pmids\": [\"24958881\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium yoelii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"The domain II (DII) loop of PfAMA1 plays a critical role in the late-stage binding event with PfRON2; computational simulation and experimental validation identified key amino acid residues in the PfRON2 helix essential for binding in the post-binding/loop-closing stage of the AMA1-RON2 interaction.\",\n      \"method\": \"Molecular dynamics simulation of DII loop dynamics, experimental validation of key residues by mutagenesis and binding assays\",\n      \"journal\": \"Chembiochem : a European journal of chemical biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — computational modeling with experimental validation of residue importance in binding, single lab\",\n      \"pmids\": [\"40067319\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"The endogenous structure of the moving junction basic repeating unit from invasion-stalled P. falciparum parasites is a 1:1:1:1 complex of PfAMA1, PfRON2, PfRON4, and PfRON5 (sailboat-shaped). PfRON2 has two transmembrane helices that anchor the complex in the RBC membrane and display an extracellular handle for PfAMA1 binding; PfAMA1 directly contacts the RBC membrane. PfRON2/4/5 form a large basic platform inside the RBC that electrostatically engages the RBC membrane and inserts seven amphipathic helices into the bilayer, suggesting active host-membrane remodeling.\",\n      \"method\": \"Cryo-EM structure determination of endogenous moving junction complex purified from invasion-stalled P. falciparum parasites; computational protein design of inhibitory binder\",\n      \"journal\": \"Cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — endogenous native complex cryo-EM structure with functional validation by designed inhibitor; mechanistically definitive\",\n      \"pmids\": [\"42379167\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"current_model\": \"PfAMA1 is a type I transmembrane micronemal protein that is processed from an 83 kDa precursor to a 66 kDa form (via removal of an N-terminal prosequence), translocates along subpellicular microtubules to the merozoite apex, and relocates to the merozoite surface at around the time of erythrocyte invasion, where it mediates merozoite reorientation and apical attachment to the host red blood cell; upon surface exposure, its cytoplasmic tail is phosphorylated at Ser610 by PfPKA (essential for function), and its ectodomain interacts via a conserved hydrophobic groove with the extracellular segment of PfRON2 (itself anchored in the RBC membrane as part of a 1:1:1:1 PfAMA1–PfRON2–PfRON4–PfRON5 moving junction complex) to trigger commitment to invasion and tight junction formation, after which the ectodomain is proteolytically shed by a membrane-bound serine sheddase (PfSUB2) at a single juxtamembrane site, and the gene itself is essential for blood-stage parasite survival.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"AMA1 (PF3D7_1133400) is a type I integral membrane protein of the apical complex that is essential for blood-stage survival and mediates the apical attachment and reorientation steps of host-cell invasion by Plasmodium merozoites [#0, #3, #11, #29]. It matures within micronemes as an 83 kDa precursor that is proteolytically processed to a 66 kDa form (removal of an N-terminal prosequence) and translocates along subpellicular microtubules to the merozoite apex before relocating to the merozoite surface at about the time of erythrocyte invasion [#6, #9, #1]. The ectodomain is folded by eight intramolecular disulfide bonds into three PAN-motif subdomains, with domain I loops presenting polymorphic residues around a conserved hydrophobic groove that forms the receptor-binding pocket [#2, #13, #14]. Through this groove — including the conserved residue Tyr251 and a surface exposed by displacement of the domain II loop — AMA1 binds the extracellular segment of PfRON2, the molecular step that commits merozoites to invasion and triggers tight-junction formation; the endogenous moving junction is a 1:1:1:1 PfAMA1–PfRON2–PfRON4–PfRON5 complex in which AMA1 directly contacts the RBC membrane [#22, #28, #26, #19, #21, #32]. AMA1 function additionally requires phosphorylation of its cytoplasmic tail at Ser610 by cAMP-dependent protein kinase A (PfPKA) [#25, #23], and following junction engagement the ectodomain is shed essentially to completion by the membrane-bound serine sheddase PfSUB2 at a single juxtamembrane site, leaving only a membrane stub carried into the host cell [#7, #16]. Because domain I polymorphisms confer escape from invasion-inhibitory antibodies while the RON2-binding pocket remains conserved, AMA1 and the AMA1–RON2 interface are foci of vaccine and inhibitor design [#12, #5, #28, #30].\"\n  ,\n  \"teleology\": [\n    {\n      \"year\": 1989,\n      \"claim\": \"Establishing where AMA1 acts required first placing the protein in the cell; its identification as an integral membrane protein of the merozoite apical complex that reaches the surface near schizont rupture defined it as an invasion-stage molecule.\",\n      \"evidence\": \"Molecular cloning with immunoelectron microscopy and immunofluorescence in P. falciparum\",\n      \"pmids\": [\"2701947\", \"2404781\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular function at the surface not yet defined\", \"Precursor processing enzyme unknown\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 1996,\n      \"claim\": \"Understanding how the ectodomain is organized and why it is antigenically variable required mapping its covalent architecture; assignment of eight disulfide bonds defined three subdomains and showed polymorphic sites cluster into conformational epitopes.\",\n      \"evidence\": \"MS, N-terminal sequencing and HPLC of baculovirus-expressed P. chabaudi AMA1\",\n      \"pmids\": [\"8910611\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"3D fold not yet resolved\", \"Receptor-binding surface not localized\"],\n      \"attribution\": [{\"species\": \"Plasmodium chabaudi\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Whether AMA1 was dispensable or required was resolved genetically; failure to disrupt the gene combined with partial cross-species complementation established essentiality for blood-stage growth and functional conservation across species.\",\n      \"evidence\": \"Knockout attempts and trans-species complementation with P. chabaudi AMA1 in P. falciparum, invasion assays\",\n      \"pmids\": [\"11115107\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Which invasion step AMA1 executes not defined\", \"Molecular partners unidentified\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}, {\"species\": \"Plasmodium chabaudi\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Linking AMA1 to a defined invasion role required trafficking and processing detail plus functional interference; independent surface translocation of the processed 66 kDa form and antibody-mediated invasion block established AMA1 as a surface-acting invasion effector, with proteolytic maturation and shedding as regulatory events.\",\n      \"evidence\": \"Immunofluorescence trafficking analysis, microsequencing/MS cleavage-site mapping, and invasion-inhibition assays with anti-3D7 AMA1 antibodies\",\n      \"pmids\": [\"12228305\", \"11399764\", \"11292751\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Shedding protease not yet identified\", \"Erythrocyte receptor unknown\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Defining the physical step AMA1 performs and how it is trafficked required ultrastructure and enzymology; microtubule-guided micronemal delivery, actin-independent surface shedding by the PfSUB2 serine sheddase at a single juxtamembrane site, and antibody evidence that AMA1 governs merozoite reorientation and apical attachment placed AMA1 at the reorientation/junction step.\",\n      \"evidence\": \"Immunoelectron microscopy, MS cleavage mapping, protease/cytochalasin D inhibitor studies, and inhibitory anti-P. knowlesi AMA1 mAb ultrastructural analysis\",\n      \"pmids\": [\"12902400\", \"12686561\", \"14688092\", \"14676185\", \"14526103\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct receptor/partner at the junction not yet identified\", \"Regulation of shedding timing unclear\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}, {\"species\": \"Plasmodium knowlesi\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Understanding the antigenic and receptor-binding basis of AMA1 required its atomic structure; crystal structures revealed PAN-domain architecture with polymorphic domain I loops surrounding a conserved hydrophobic trough, allelic exchange showed domain I polymorphisms drive antibody escape, and candidate erythrocyte interactions (domain III–Kx) and shedding-site chemistry were defined.\",\n      \"evidence\": \"X-ray crystallography of P. falciparum DI+II and P. vivax ectodomain, allelic-exchange transgenics, CHO-based binding/Kx-null invasion assays, MS mapping of the Thr517 shedding site\",\n      \"pmids\": [\"16129835\", \"15731407\", \"15049818\", \"15805191\", \"16102004\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological ligand of the hydrophobic trough still unknown\", \"Kx interaction not integrated into a mechanistic model\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}, {\"species\": \"Plasmodium vivax\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Locating the functional inhibitory hotspot required epitope mapping and partner identification; peptide/antibody structures pinpointed the hydrophobic cleft and domain II loop as invasion-critical, and co-immunoprecipitation of PfAMA1 with PfRON4 first tied AMA1 to a conserved rhoptry-neck moving-junction complex.\",\n      \"evidence\": \"NMR of the R1 peptide, IgNAR and mAb 4G2 epitope mapping/co-crystals with functional invasion assays, and Co-IP with immuno-EM of PfRON4\",\n      \"pmids\": [\"16177378\", \"17997971\", \"17192270\", \"16835460\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct AMA1 partner in the pocket not yet identified (RON4 interaction indirect)\", \"Complex stoichiometry unknown\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Determining what the hydrophobic groove actually binds and how AMA1 is activated required residue-level and cytoplasmic-domain dissection; Tyr251 was shown essential for complex formation, the cytoplasmic tail was found dispensable for trafficking but essential and phosphoregulated for invasion, extending AMA1 control beyond the ectodomain.\",\n      \"evidence\": \"Site-directed mutagenesis with 4G2 competition Co-IP, and cytoplasmic-domain swap/GFP complementation with live imaging in transgenic P. falciparum\",\n      \"pmids\": [\"19165323\", \"19283086\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Identity of the pocket ligand still not proven to be RON2\", \"Kinase and phosphosite not yet identified\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Establishing the causal molecular trigger and its species-specificity required linking pocket occupancy to a defined invasion decision; PfRON2 binding to the AMA1 pocket was shown to commit merozoites to invasion and trigger junction formation, distinct from vacuole induction, while genetics revealed AMA1 is required for erythrocyte but not sporozoite invasion in P. berghei.\",\n      \"evidence\": \"PfRON2/PfRON4 Co-IP and localization, AMA1-pocket and RON2-cysteine mutagenesis, R1 competition with epistatic ordering, Ser610Ala mutagenesis with PfPKA inhibition, and conditional knockout in P. berghei / T. gondii\",\n      \"pmids\": [\"21788485\", \"20228060\", \"18952195\", \"20532217\", \"22177563\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Atomic details of the AMA1–RON2 interface not yet resolved\", \"How Ser610 phosphorylation couples to invasion mechanically unknown\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}, {\"species\": \"Plasmodium berghei\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Refining AMA1's function beyond entry required conditional depletion and structure; DiCre excision showed AMA1 is essential for invasion and additionally required for post-invasion sealing of the parasitophorous vacuole, and the AMA1–RON2 co-crystal defined the groove plus domain-II-loop-displacement interface that RON2 (and the mimetic R1) engage.\",\n      \"evidence\": \"Conditional DiCre knockdown with growth/invasion analysis, and X-ray co-crystallography of the AMA1–RON2 peptide complex with alanine-scanning mutagenesis\",\n      \"pmids\": [\"24571085\", \"22737069\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of vacuole-sealing role not defined\", \"Full native junction architecture not yet resolved\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Resolving the assembled junction as it operates required a native structure; cryo-EM of the endogenous 1:1:1:1 PfAMA1–PfRON2–PfRON4–PfRON5 unit from invasion-stalled parasites showed RON2 anchored in the RBC membrane displaying an extracellular handle for AMA1, AMA1 directly contacting the RBC membrane, and a RON2/4/5 platform inserting amphipathic helices into the host bilayer, while MD/mutagenesis refined the late DII-loop-closing binding step.\",\n      \"evidence\": \"Cryo-EM of endogenous moving-junction complex with computational inhibitor design, and molecular dynamics with mutagenesis/binding validation of the DII loop\",\n      \"pmids\": [\"42379167\", \"40067319\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Dynamics of AMA1 conformational change during junction traversal not fully resolved\", \"How PfSUB2 shedding is coordinated with the assembled junction unclear\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How AMA1 mechanically couples its RON2-engaged ectodomain and Ser610-phosphorylated cytoplasmic tail to the actomyosin motor to drive host-membrane remodeling and vacuole sealing remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structure of the phosphorylated cytoplasmic tail engaged with motor components\", \"Mechanochemical link between junction engagement and force transmission undefined\", \"Molecular basis of the post-invasion vacuole-sealing role unknown\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005102\", \"supporting_discovery_ids\": [15, 19, 21, 22, 26, 28, 32]},\n      {\"term_id\": \"GO:0050839\", \"supporting_discovery_ids\": [11, 26]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0020009\", \"supporting_discovery_ids\": [0, 9]},\n      {\"term_id\": \"GO:0009986\", \"supporting_discovery_ids\": [0, 1, 4, 6]},\n      {\"term_id\": \"GO:0016020\", \"supporting_discovery_ids\": [1, 0]},\n      {\"term_id\": \"GO:0033644\", \"supporting_discovery_ids\": [32]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0044409\", \"supporting_discovery_ids\": [3, 5, 11, 26, 27, 29]},\n      {\"term_id\": \"GO:0006468\", \"supporting_discovery_ids\": [25, 23]},\n      {\"term_id\": \"GO:0016485\", \"supporting_discovery_ids\": [6, 7, 16]}\n    ],\n    \"complexes\": [\n      \"PfAMA1-PfRON2-PfRON4-PfRON5 moving junction complex (1:1:1:1) [#32]\",\n      \"PfAMA1-PfRON4 co-immunoprecipitated complex [#19]\",\n      \"PfAMA1-PfRON2-PfRON4 complex [#21]\"\n    ],\n    \"partners\": [\n      \"PfRON2 (rhoptry neck protein; binds AMA1 hydrophobic groove) [#26, #28, #21, #32, #31]\",\n      \"PfRON4 [#19, #21, #32]\",\n      \"PfRON5 [#32]\",\n      \"PfSUB2 (membrane-bound serine sheddase that sheds the ectodomain) [#7]\",\n      \"PfPKA (cAMP-dependent protein kinase A; phosphorylates cytoplasmic Ser610) [#25]\",\n      \"Kx erythrocyte membrane protein (binds domain III after trypsin treatment) [#15]\"\n    ],\n    \"other_free_text\": [\n      \"83 kDa precursor processed to 66 kDa mature form by removal of N-terminal prosequence [#6]\",\n      \"Ectodomain contains 8 disulfide bonds defining three PAN-motif subdomains; polymorphic residues cluster in domain I around a conserved hydrophobic groove/trough [#2, #13, #14]\",\n      \"Ectodomain shed to completion at a single juxtamembrane site (Thr517), leaving a membrane stub carried into the host cell [#16, #7]\",\n      \"Cytoplasmic tail phosphorylated at Ser610; essential for invasion but dispensable for trafficking [#25, #23]\",\n      \"Domain I polymorphisms confer escape from invasion-inhibitory antibodies; RON2-binding pocket conserved [#12, #5]\",\n      \"AMA1-RON2 peptide complex immunization confers protection and shifts antibody specificity toward loops around the RON2 site [#30]\",\n      \"Species divergence: AMA1 required for merozoite (erythrocyte) invasion but dispensable for P. berghei sporozoite invasion of hepatocytes and enhances but is not required for T. gondii junction assembly [#27]\"\n    ]\n  }\n}","audit_flag":null,"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_1133400","name":null,"product":"apical membrane antigen 1","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_0915000","name":null,"product":"apical membrane antigen 1","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_0931500","name":null,"product":"apical membrane antigen 1","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"AMA1","evaluation":null}