{"gene":"PF3D7_1222700","run_date":"2026-09-08T16:55:26+00:00","timeline":{"discoveries":[{"year":2006,"finding":"GAP45 is dually acylated (N-myristoylation and palmitoylation) in P. falciparum merozoites, as demonstrated by metabolic labeling and mutagenesis experiments on the 45 kDa glideosome-associated protein.","method":"Metabolic labeling with fatty acid analogues, mutagenesis of acylation sites","journal":"Molecular and biochemical parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct biochemical labeling and mutagenesis in a single study; dual acylation established by orthogonal methods","pmids":["16750579"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2006,"finding":"GAP45 forms a complex with PfGAP50 and PfMyoA (the glideosome) in late schizonts and merozoites of P. falciparum, as shown by co-immunoprecipitation and localization studies consistent with a role in erythrocyte invasion.","method":"Co-immunoprecipitation, immunofluorescence","journal":"Molecular and biochemical parasitology","confidence":"Medium","confidence_rationale":"Tier 3 / Strong — Co-IP demonstrated, replicated across multiple papers with consistent results","pmids":["16513191","17553576"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2008,"finding":"GAP45 is phosphorylated by P. falciparum CDPK1 in vitro at two sites (one of which was also detected in phosphopeptides from parasite lysates), establishing GAP45 as a substrate of CDPK1 in the motor complex.","method":"In vitro kinase assay with recombinant PfCDPK1, mass spectrometry of phosphopeptides from parasite lysates","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro kinase assay plus detection of phosphorylation in parasite lysates, replicated in subsequent studies","pmids":["18768477"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2007,"finding":"PfPKB (a Ca2+/calmodulin-activated protein kinase B-like enzyme) associates with the actin-myosin motor complex and phosphorylates GAP45 in P. falciparum, linking calcium signaling to motor complex regulation during erythrocyte invasion.","method":"Co-immunoprecipitation, in vitro kinase assay","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP and in vitro kinase assay in a single lab; replicated for phosphorylation sites in a subsequent study","pmids":["18165240"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2009,"finding":"PfCDPK1 phosphorylates GAP45 in vitro at nine sites (Ser31, Ser89, Ser103, Ser109, Ser121, Ser149, Ser156, Thr158, and Ser173), and phosphorylation at these sites alters proteolytic cleavage properties and kinase substrate properties of GAP45.","method":"In vitro phosphorylation by PfCDPK1, nano-UPLC-MS/MS, phosphopeptide enrichment by Ga(III) IMAC, synthetic phosphopeptide substrate assays","journal":"Analytical biochemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — rigorous in vitro phosphorylation mapping by mass spectrometry with multiple proteases and synthetic peptide validation in a single study","pmids":["19549500"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2009,"finding":"Inhibition of cADPR-mediated calcium release does not affect GAP45 phosphorylation or glideosome association, but the serine/threonine kinase inhibitor staurosporine affects GAP45 isoform distribution and integrity of the glideosome complex, indicating that assembly of the glideosome is dynamically regulated.","method":"Pharmacological inhibition (cADPR pathway inhibitors, staurosporine), immunoprecipitation, isoform analysis by gel electrophoresis","journal":"Molecular and biochemical parasitology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — pharmacological dissection with co-immunoprecipitation readout; single lab, two complementary approaches","pmids":["19576251"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2010,"finding":"GAP45 is anchored to both the plasma membrane (via N-terminal acylation) and the inner membrane complex (via its C-terminal extremity); the C-terminal region recruits MLC1-MyoA to the IMC, while the N-terminal acylation and coiled-coil domain preserve pellicle integrity during invasion. GAP45 is essential for gliding, invasion, and egress in Toxoplasma, and the P. falciparum GAP45 ortholog can functionally complement the Toxoplasma GAP45, shown by transgenera complementation.","method":"Conditional knockdown/deletion, domain mutagenesis, transgenera complementation, immunofluorescence","journal":"Cell host & microbe","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic complementation across genera plus domain mutagenesis establishing N- and C-terminal functional roles; multiple orthogonal methods","pmids":["20951968"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2012,"finding":"GAP45 tagged internally with GFP is assembled into the motor complex and transported to the developing IMC in early schizogony in P. falciparum, accumulating there throughout intracellular development until merozoite release; CDPK1 phosphorylates GAP45 in vivo, but substitution of the identified serine residues with alanine or aspartate has no apparent effect on GAP45 assembly into the motor complex or its subcellular localization.","method":"GFP-tagging and live imaging, immunoprecipitation, in vitro kinase assay, site-directed mutagenesis","journal":"PloS one","confidence":"High","confidence_rationale":"Tier 2 / Moderate — live imaging plus co-immunoprecipitation plus mutagenesis in a single rigorous study; also includes negative result for phosphorylation-site mutations","pmids":["22479457"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2012,"finding":"GAP45 is phosphorylated by both PfPKB and PfCDPK1 at S89, S103, and S149 in response to phospholipase C and calcium signaling; the PLC pathway specifically influences phosphorylation at S103 and S149; however, localization of GAP45 and its association with the glideosome appear independent of phosphorylation at these sites.","method":"In vitro kinase assay, site-directed mutagenesis, pharmacological inhibition of PLC pathway, co-immunoprecipitation","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro kinase assay with mutagenesis and pharmacological dissection; single lab, multiple methods","pmids":["22558243"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2012,"finding":"GAP45 was identified as a substrate of cAMP-dependent protein kinase A (PKA) in P. falciparum schizonts, verified by in vitro kinase assay, implicating PKA as an additional regulator of the glideosome motor complex alongside CDPK1.","method":"Phosphoproteomic analysis of schizont stage, in vitro PKA kinase assay","journal":"Journal of proteome research","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — in vitro kinase assay established GAP45 as a PKA substrate; single lab, single method for this specific finding","pmids":["23025827"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2018,"finding":"Conditional deletion of GAP45 in asexual blood stages of P. falciparum confirms its essential role in erythrocyte invasion but shows it is NOT required for merozoite egress from red blood cells, demonstrating that the actinomyosin motor is dispensable for egress.","method":"Conditional genetic deletion (DiCre recombinase system), invasion assays, egress assays, electron microscopy","journal":"mBio","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional KO with rigorous invasion and egress phenotypic readouts; directly establishes essential role in invasion and negative result for egress","pmids":["29970464"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2021,"finding":"N-myristoylation of GAP45 is essential for erythrocyte invasion in P. falciparum: replacement of the N-terminal glycine with alanine to prevent myristoylation had no impact on GAP45 protein localization or glideosome assembly, but abolished invasion, showing that myristoylation provides a function distinct from membrane targeting per se.","method":"NMT inhibitor treatment, site-directed mutagenesis (Gly→Ala), invasion assays, immunofluorescence, chemical proteomics for NMT substrate identification","journal":"PLoS biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic mutagenesis plus chemical inhibition with quantitative invasion readout; multiple orthogonal approaches in a single rigorous study","pmids":["34695132"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2022,"finding":"DHHC2, the major palmitoyl-acyl-transferase of the IMC in Plasmodium yoelii, palmitoylates GAP45 for its IMC localization; depletion of DHHC2 disrupts GAP45 IMC targeting, demonstrating that palmitoylation by DHHC2 is required for proper GAP45 subcellular localization during schizont development.","method":"TurboID proximity labeling (IMC proteomics), conditional DHHC2 depletion, palmitoylation assay, immunofluorescence","journal":"eLife","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — proximity labeling plus conditional KD plus palmitoylation assay; single lab, multiple orthogonal methods","pmids":["35775739"],"is_preprint":false,"attribution":[{"species":"Plasmodium yoelii","strain":""}]},{"year":2023,"finding":"PfGAP40 co-precipitates with GAP45 and PfGAP50 in P. falciparum, and knockdown of PfGAP40 reduces the expression levels of GAP45 and PfGAP50 in the schizont stage, indicating that GAP40 stabilizes GAP45 protein levels within the glideosome.","method":"Conditional knockdown, co-immunoprecipitation, western blotting","journal":"Microbiology spectrum","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — Co-IP plus conditional KD with protein level readout; single lab, two orthogonal approaches","pmids":["37249423"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2011,"finding":"PfGAP50-GFP immunoprecipitation co-precipitates endogenous GAP45 and MTIP, confirming that GAP45 is part of the core glideosome complex anchored to the IMC via GAP50.","method":"Immunoprecipitation of GFP-tagged GAP50, fluorescence photobleaching, immunofluorescence","journal":"Eukaryotic cell","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — Co-IP with GFP-tagged partner confirms complex membership; single lab, replicated across studies","pmids":["21239623"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"current_model":"GAP45 (PF3D7_1222700) is a dually acylated (N-myristoylated by NMT and palmitoylated by DHHC2) peripheral membrane protein that bridges the plasma membrane and inner membrane complex (IMC) of P. falciparum merozoites; its C-terminal domain recruits the MyoA–MTIP myosin complex to the IMC while its N-terminal acylation and coiled-coil domain maintain pellicle integrity, and it is phosphorylated at multiple serine residues by at least three kinases (CDPK1, PfPKB, and PKA) in a calcium- and cAMP-dependent manner; conditional deletion confirms GAP45 is essential for erythrocyte invasion but dispensable for egress, and specifically the N-myristoylation of GAP45—though not required for its localization or glideosome assembly—is required for a functional invasion step."},"narrative":{"mechanistic_narrative":"GAP45 (PF3D7_1222700) is a dually acylated peripheral membrane protein of the Plasmodium falciparum glideosome that is essential for erythrocyte invasion but dispensable for merozoite egress [PMID:29970464]. It is N-myristoylated and palmitoylated [PMID:16750579], and these two modifications serve distinct functions: palmitoylation—shown in the P. yoelii ortholog to depend on the IMC palmitoyl-acyl-transferase DHHC2—directs GAP45 to the inner membrane complex (IMC) [PMID:35775739], whereas N-myristoylation is dispensable for localization and glideosome assembly yet is strictly required for a functional invasion step [PMID:34695132]. Structurally, GAP45 bridges the plasma membrane (via N-terminal acylation) and the IMC (via its C-terminal extremity), with the C-terminal region recruiting the MyoA/MLC1 motor to the IMC and the N-terminal acylation and coiled-coil domain preserving pellicle integrity, a role conserved enough that P. falciparum GAP45 complements the Toxoplasma ortholog [PMID:20951968]. As a core glideosome component it assembles with GAP50, MyoA, and MTIP and is transported to the developing IMC throughout schizogony [PMID:16513191, PMID:17553576, PMID:21239623, PMID:22479457], with GAP40 required to stabilize its steady-state protein level [PMID:37249423]. GAP45 is a convergence point for signaling, being phosphorylated at multiple serine/threonine residues by CDPK1, PfPKB, and PKA in a calcium- and cAMP-responsive manner [PMID:18768477, PMID:19549500, PMID:22558243, PMID:23025827]; however, these phosphorylation events are not required for its localization or glideosome assembly [PMID:22479457, PMID:22558243].","teleology":[{"year":2006,"claim":"Establishing how GAP45 attaches to membranes was the first mechanistic question, and dual acylation was shown to provide its membrane anchoring.","evidence":"Metabolic labeling with fatty acid analogues and mutagenesis of acylation sites in P. falciparum merozoites","pmids":["16750579"],"confidence":"Medium","gaps":["Did not establish which acyltransferases add the modifications","Did not distinguish the functional roles of myristoylation versus palmitoylation"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2006,"claim":"Whether GAP45 physically belongs to the invasion motor was resolved by demonstrating its assembly into the glideosome with GAP50 and MyoA.","evidence":"Co-immunoprecipitation and immunofluorescence in late schizonts and merozoites of P. falciparum","pmids":["16513191","17553576"],"confidence":"Medium","gaps":["Co-IP alone did not define direct versus indirect contacts","Did not resolve the domain of GAP45 mediating complex assembly"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2007,"claim":"Linking calcium signaling to motor regulation, PfPKB was found to associate with the motor complex and phosphorylate GAP45.","evidence":"Co-immunoprecipitation and in vitro kinase assay in P. falciparum","pmids":["18165240"],"confidence":"Medium","gaps":["Functional consequence of PfPKB phosphorylation on invasion not tested","Phosphosites not mapped in this study"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2008,"claim":"Identifying the kinases acting on the motor, GAP45 was established as a CDPK1 substrate with phosphorylation detectable in parasite lysates.","evidence":"In vitro kinase assay with recombinant PfCDPK1 and mass spectrometry of phosphopeptides from parasite lysates","pmids":["18768477"],"confidence":"High","gaps":["Physiological role of CDPK1 phosphorylation of GAP45 not established","Only two sites identified at this stage"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2009,"claim":"The full CDPK1 phosphosite repertoire on GAP45 was mapped and shown to alter its proteolytic and substrate properties, refining the picture of regulated modification.","evidence":"In vitro PfCDPK1 phosphorylation, nano-UPLC-MS/MS with IMAC enrichment, and synthetic phosphopeptide assays","pmids":["19549500"],"confidence":"High","gaps":["In vitro mapping did not confirm all nine sites are used in vivo","Downstream effect on motor function untested"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2009,"claim":"Whether glideosome assembly is static or regulated was addressed pharmacologically, showing kinase activity influences GAP45 isoform distribution and complex integrity while cADPR calcium release does not.","evidence":"Pharmacological inhibition (cADPR inhibitors, staurosporine), immunoprecipitation, and isoform analysis in P. falciparum","pmids":["19576251"],"confidence":"Medium","gaps":["Staurosporine is nonspecific and did not identify the responsible kinase","Link between isoform shift and invasion outcome not established"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2010,"claim":"The domain architecture underlying GAP45's bridging function was defined, assigning C-terminal motor recruitment and N-terminal pellicle-integrity roles, with cross-genera complementation confirming conserved function.","evidence":"Conditional knockdown/deletion, domain mutagenesis, transgenera complementation, and immunofluorescence","pmids":["20951968"],"confidence":"High","gaps":["Egress requirement in P. falciparum not directly tested here","Structural basis of C-terminal MLC1-MyoA recruitment not resolved"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2011,"claim":"Complex membership was corroborated from the GAP50 anchor side, confirming GAP45 and MTIP are co-recruited to the IMC.","evidence":"Immunoprecipitation of GFP-tagged GAP50 with photobleaching and immunofluorescence in P. falciparum","pmids":["21239623"],"confidence":"Medium","gaps":["Did not determine assembly order of components","Direct GAP45-GAP50 contact not resolved"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2012,"claim":"Whether phosphorylation controls GAP45 assembly/localization was tested directly, and phosphosite mutagenesis showed it does not, decoupling modification from trafficking; in parallel PLC/calcium and PKA inputs were mapped onto specific serines.","evidence":"GFP-tagging and live imaging, in vitro kinase assays, site-directed mutagenesis, PLC inhibition, and PKA phosphoproteomics in P. falciparum schizonts","pmids":["22479457","22558243","23025827"],"confidence":"High","gaps":["Functional readout of the phosphosite mutants on invasion not resolved","How three kinases are coordinated on GAP45 in vivo unknown","Whether phosphorylation regulates motor force or dynamics untested"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2018,"claim":"Conditional deletion settled the physiological requirement, showing GAP45 is essential for invasion but dispensable for egress and thereby that the actinomyosin motor is not needed for egress.","evidence":"DiCre conditional deletion with invasion/egress assays and electron microscopy in P. falciparum asexual blood stages","pmids":["29970464"],"confidence":"High","gaps":["Molecular step of invasion that fails without GAP45 not pinpointed","Did not dissect contributions of individual GAP45 modifications"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2021,"claim":"The specific role of N-myristoylation was isolated, revealing it is required for a functional invasion step independent of membrane targeting or glideosome assembly.","evidence":"NMT inhibition, Gly-to-Ala myristoylation-site mutagenesis, invasion assays, immunofluorescence, and chemical proteomics in P. falciparum","pmids":["34695132"],"confidence":"High","gaps":["The distinct invasion function conferred by myristoylation not mechanistically defined","Interplay with palmitoylation not addressed"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2022,"claim":"The enzyme responsible for GAP45 IMC targeting was identified, showing DHHC2-mediated palmitoylation directs its IMC localization.","evidence":"TurboID IMC proteomics, conditional DHHC2 depletion, palmitoylation assay, and immunofluorescence in P. yoelii","pmids":["35775739"],"confidence":"Medium","gaps":["Shown in P. yoelii, not directly confirmed for the P. falciparum ortholog","Whether DHHC2 loss phenocopies GAP45 mislocalization on invasion untested"],"attribution":[{"species":"Plasmodium yoelii","strain":""}]},{"year":2023,"claim":"A determinant of GAP45 steady-state abundance was found, with GAP40 required to stabilize GAP45 protein levels within the glideosome.","evidence":"Conditional knockdown of PfGAP40, co-immunoprecipitation, and western blotting in P. falciparum","pmids":["37249423"],"confidence":"Medium","gaps":["Mechanism of GAP40-dependent stabilization unknown","Whether reduced GAP45 fully accounts for GAP40 knockdown phenotype not resolved"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":null,"claim":"The precise molecular step of invasion that requires GAP45 N-myristoylation, and how multi-kinase phosphorylation is integrated to regulate motor function, remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of the GAP45-anchored motor at the pellicle","Functional output of the mapped phosphosites on motor force/dynamics undefined","Molecular function distinguishing myristoylation from palmitoylation in invasion unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["Glideosome (GAP45–GAP50–MyoA/PfMyoA–MTIP/MLC1–GAP40)"],"partners":["PFGAP50","PFMYOA","MTIP/MLC1","PFGAP40","PFCDPK1 (KINASE)","PFPKB (KINASE)","PFPKA (KINASE)","DHHC2 (PALMITOYL-ACYL-TRANSFERASE, P. YOELII)","NMT (N-MYRISTOYLTRANSFERASE)"],"other_free_text":["GAP45 bridges the plasma membrane and inner membrane complex, with C-terminal recruitment of the MyoA/MLC1 motor and N-terminal acylation plus coiled-coil maintaining pellicle integrity [#6].","N-myristoylation is dispensable for localization and glideosome assembly but essential for a functional invasion step [#11].","DHHC2-dependent palmitoylation directs IMC localization, demonstrated in the P. yoelii ortholog [#12].","GAP45 is phosphorylated at multiple mapped serine/threonine residues (including Ser89, Ser103, Ser149) by CDPK1, PfPKB, and PKA, but these modifications are not required for localization or glideosome assembly [#4, #7, #8, #9].","Conditional deletion shows GAP45 is essential for erythrocyte invasion but dispensable for egress [#10]."]}},"prefetch_data":{},"corpus_meta":[{"pmid":"16321976","id":"PMC_16321976","title":"A conserved molecular motor drives cell invasion and gliding motility across malaria life 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spectrum","url":"https://pubmed.ncbi.nlm.nih.gov/37249423","citation_count":7,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfGAP45"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":12751,"output_tokens":4008,"usd":0.049187,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":10021,"output_tokens":4948,"usd":0.086902,"stage2_stop_reason":"end_turn"},"total_usd":0.0,"stage1_batch_id":"msgbatch_01BW7vvc7h5iV39oJ1MHMzXw","stage2_batch_id":"msgbatch_01Kh5HbgbPXepNfNCbktYkSD","note":"batch pricing = 50% of standard","skipped":true},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2006,\n      \"finding\": \"GAP45 is dually acylated (N-myristoylation and palmitoylation) in P. falciparum merozoites, as demonstrated by metabolic labeling and mutagenesis experiments on the 45 kDa glideosome-associated protein.\",\n      \"method\": \"Metabolic labeling with fatty acid analogues, mutagenesis of acylation sites\",\n      \"journal\": \"Molecular and biochemical parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct biochemical labeling and mutagenesis in a single study; dual acylation established by orthogonal methods\",\n      \"pmids\": [\"16750579\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"GAP45 forms a complex with PfGAP50 and PfMyoA (the glideosome) in late schizonts and merozoites of P. falciparum, as shown by co-immunoprecipitation and localization studies consistent with a role in erythrocyte invasion.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescence\",\n      \"journal\": \"Molecular and biochemical parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Strong — Co-IP demonstrated, replicated across multiple papers with consistent results\",\n      \"pmids\": [\"16513191\", \"17553576\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"GAP45 is phosphorylated by P. falciparum CDPK1 in vitro at two sites (one of which was also detected in phosphopeptides from parasite lysates), establishing GAP45 as a substrate of CDPK1 in the motor complex.\",\n      \"method\": \"In vitro kinase assay with recombinant PfCDPK1, mass spectrometry of phosphopeptides from parasite lysates\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro kinase assay plus detection of phosphorylation in parasite lysates, replicated in subsequent studies\",\n      \"pmids\": [\"18768477\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"PfPKB (a Ca2+/calmodulin-activated protein kinase B-like enzyme) associates with the actin-myosin motor complex and phosphorylates GAP45 in P. falciparum, linking calcium signaling to motor complex regulation during erythrocyte invasion.\",\n      \"method\": \"Co-immunoprecipitation, in vitro kinase assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP and in vitro kinase assay in a single lab; replicated for phosphorylation sites in a subsequent study\",\n      \"pmids\": [\"18165240\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"PfCDPK1 phosphorylates GAP45 in vitro at nine sites (Ser31, Ser89, Ser103, Ser109, Ser121, Ser149, Ser156, Thr158, and Ser173), and phosphorylation at these sites alters proteolytic cleavage properties and kinase substrate properties of GAP45.\",\n      \"method\": \"In vitro phosphorylation by PfCDPK1, nano-UPLC-MS/MS, phosphopeptide enrichment by Ga(III) IMAC, synthetic phosphopeptide substrate assays\",\n      \"journal\": \"Analytical biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — rigorous in vitro phosphorylation mapping by mass spectrometry with multiple proteases and synthetic peptide validation in a single study\",\n      \"pmids\": [\"19549500\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Inhibition of cADPR-mediated calcium release does not affect GAP45 phosphorylation or glideosome association, but the serine/threonine kinase inhibitor staurosporine affects GAP45 isoform distribution and integrity of the glideosome complex, indicating that assembly of the glideosome is dynamically regulated.\",\n      \"method\": \"Pharmacological inhibition (cADPR pathway inhibitors, staurosporine), immunoprecipitation, isoform analysis by gel electrophoresis\",\n      \"journal\": \"Molecular and biochemical parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — pharmacological dissection with co-immunoprecipitation readout; single lab, two complementary approaches\",\n      \"pmids\": [\"19576251\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"GAP45 is anchored to both the plasma membrane (via N-terminal acylation) and the inner membrane complex (via its C-terminal extremity); the C-terminal region recruits MLC1-MyoA to the IMC, while the N-terminal acylation and coiled-coil domain preserve pellicle integrity during invasion. GAP45 is essential for gliding, invasion, and egress in Toxoplasma, and the P. falciparum GAP45 ortholog can functionally complement the Toxoplasma GAP45, shown by transgenera complementation.\",\n      \"method\": \"Conditional knockdown/deletion, domain mutagenesis, transgenera complementation, immunofluorescence\",\n      \"journal\": \"Cell host & microbe\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic complementation across genera plus domain mutagenesis establishing N- and C-terminal functional roles; multiple orthogonal methods\",\n      \"pmids\": [\"20951968\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"GAP45 tagged internally with GFP is assembled into the motor complex and transported to the developing IMC in early schizogony in P. falciparum, accumulating there throughout intracellular development until merozoite release; CDPK1 phosphorylates GAP45 in vivo, but substitution of the identified serine residues with alanine or aspartate has no apparent effect on GAP45 assembly into the motor complex or its subcellular localization.\",\n      \"method\": \"GFP-tagging and live imaging, immunoprecipitation, in vitro kinase assay, site-directed mutagenesis\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — live imaging plus co-immunoprecipitation plus mutagenesis in a single rigorous study; also includes negative result for phosphorylation-site mutations\",\n      \"pmids\": [\"22479457\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"GAP45 is phosphorylated by both PfPKB and PfCDPK1 at S89, S103, and S149 in response to phospholipase C and calcium signaling; the PLC pathway specifically influences phosphorylation at S103 and S149; however, localization of GAP45 and its association with the glideosome appear independent of phosphorylation at these sites.\",\n      \"method\": \"In vitro kinase assay, site-directed mutagenesis, pharmacological inhibition of PLC pathway, co-immunoprecipitation\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro kinase assay with mutagenesis and pharmacological dissection; single lab, multiple methods\",\n      \"pmids\": [\"22558243\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"GAP45 was identified as a substrate of cAMP-dependent protein kinase A (PKA) in P. falciparum schizonts, verified by in vitro kinase assay, implicating PKA as an additional regulator of the glideosome motor complex alongside CDPK1.\",\n      \"method\": \"Phosphoproteomic analysis of schizont stage, in vitro PKA kinase assay\",\n      \"journal\": \"Journal of proteome research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — in vitro kinase assay established GAP45 as a PKA substrate; single lab, single method for this specific finding\",\n      \"pmids\": [\"23025827\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Conditional deletion of GAP45 in asexual blood stages of P. falciparum confirms its essential role in erythrocyte invasion but shows it is NOT required for merozoite egress from red blood cells, demonstrating that the actinomyosin motor is dispensable for egress.\",\n      \"method\": \"Conditional genetic deletion (DiCre recombinase system), invasion assays, egress assays, electron microscopy\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional KO with rigorous invasion and egress phenotypic readouts; directly establishes essential role in invasion and negative result for egress\",\n      \"pmids\": [\"29970464\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"N-myristoylation of GAP45 is essential for erythrocyte invasion in P. falciparum: replacement of the N-terminal glycine with alanine to prevent myristoylation had no impact on GAP45 protein localization or glideosome assembly, but abolished invasion, showing that myristoylation provides a function distinct from membrane targeting per se.\",\n      \"method\": \"NMT inhibitor treatment, site-directed mutagenesis (Gly→Ala), invasion assays, immunofluorescence, chemical proteomics for NMT substrate identification\",\n      \"journal\": \"PLoS biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic mutagenesis plus chemical inhibition with quantitative invasion readout; multiple orthogonal approaches in a single rigorous study\",\n      \"pmids\": [\"34695132\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"DHHC2, the major palmitoyl-acyl-transferase of the IMC in Plasmodium yoelii, palmitoylates GAP45 for its IMC localization; depletion of DHHC2 disrupts GAP45 IMC targeting, demonstrating that palmitoylation by DHHC2 is required for proper GAP45 subcellular localization during schizont development.\",\n      \"method\": \"TurboID proximity labeling (IMC proteomics), conditional DHHC2 depletion, palmitoylation assay, immunofluorescence\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — proximity labeling plus conditional KD plus palmitoylation assay; single lab, multiple orthogonal methods\",\n      \"pmids\": [\"35775739\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium yoelii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"PfGAP40 co-precipitates with GAP45 and PfGAP50 in P. falciparum, and knockdown of PfGAP40 reduces the expression levels of GAP45 and PfGAP50 in the schizont stage, indicating that GAP40 stabilizes GAP45 protein levels within the glideosome.\",\n      \"method\": \"Conditional knockdown, co-immunoprecipitation, western blotting\",\n      \"journal\": \"Microbiology spectrum\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — Co-IP plus conditional KD with protein level readout; single lab, two orthogonal approaches\",\n      \"pmids\": [\"37249423\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"PfGAP50-GFP immunoprecipitation co-precipitates endogenous GAP45 and MTIP, confirming that GAP45 is part of the core glideosome complex anchored to the IMC via GAP50.\",\n      \"method\": \"Immunoprecipitation of GFP-tagged GAP50, fluorescence photobleaching, immunofluorescence\",\n      \"journal\": \"Eukaryotic cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — Co-IP with GFP-tagged partner confirms complex membership; single lab, replicated across studies\",\n      \"pmids\": [\"21239623\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"current_model\": \"GAP45 (PF3D7_1222700) is a dually acylated (N-myristoylated by NMT and palmitoylated by DHHC2) peripheral membrane protein that bridges the plasma membrane and inner membrane complex (IMC) of P. falciparum merozoites; its C-terminal domain recruits the MyoA–MTIP myosin complex to the IMC while its N-terminal acylation and coiled-coil domain maintain pellicle integrity, and it is phosphorylated at multiple serine residues by at least three kinases (CDPK1, PfPKB, and PKA) in a calcium- and cAMP-dependent manner; conditional deletion confirms GAP45 is essential for erythrocyte invasion but dispensable for egress, and specifically the N-myristoylation of GAP45—though not required for its localization or glideosome assembly—is required for a functional invasion step.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"GAP45 (PF3D7_1222700) is a dually acylated peripheral membrane protein of the Plasmodium falciparum glideosome that is essential for erythrocyte invasion but dispensable for merozoite egress [#10]. It is N-myristoylated and palmitoylated [#0], and these two modifications serve distinct functions: palmitoylation—shown in the P. yoelii ortholog to depend on the IMC palmitoyl-acyl-transferase DHHC2—directs GAP45 to the inner membrane complex (IMC) [#12], whereas N-myristoylation is dispensable for localization and glideosome assembly yet is strictly required for a functional invasion step [#11]. Structurally, GAP45 bridges the plasma membrane (via N-terminal acylation) and the IMC (via its C-terminal extremity), with the C-terminal region recruiting the MyoA/MLC1 motor to the IMC and the N-terminal acylation and coiled-coil domain preserving pellicle integrity, a role conserved enough that P. falciparum GAP45 complements the Toxoplasma ortholog [#6]. As a core glideosome component it assembles with GAP50, MyoA, and MTIP and is transported to the developing IMC throughout schizogony [#1, #14, #7], with GAP40 required to stabilize its steady-state protein level [#13]. GAP45 is a convergence point for signaling, being phosphorylated at multiple serine/threonine residues by CDPK1, PfPKB, and PKA in a calcium- and cAMP-responsive manner [#2, #4, #8, #9]; however, these phosphorylation events are not required for its localization or glideosome assembly [#7, #8].\",\n  \"teleology\": [\n    {\n      \"year\": 2006,\n      \"claim\": \"Establishing how GAP45 attaches to membranes was the first mechanistic question, and dual acylation was shown to provide its membrane anchoring.\",\n      \"evidence\": \"Metabolic labeling with fatty acid analogues and mutagenesis of acylation sites in P. falciparum merozoites\",\n      \"pmids\": [\"16750579\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not establish which acyltransferases add the modifications\", \"Did not distinguish the functional roles of myristoylation versus palmitoylation\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Whether GAP45 physically belongs to the invasion motor was resolved by demonstrating its assembly into the glideosome with GAP50 and MyoA.\",\n      \"evidence\": \"Co-immunoprecipitation and immunofluorescence in late schizonts and merozoites of P. falciparum\",\n      \"pmids\": [\"16513191\", \"17553576\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Co-IP alone did not define direct versus indirect contacts\", \"Did not resolve the domain of GAP45 mediating complex assembly\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Linking calcium signaling to motor regulation, PfPKB was found to associate with the motor complex and phosphorylate GAP45.\",\n      \"evidence\": \"Co-immunoprecipitation and in vitro kinase assay in P. falciparum\",\n      \"pmids\": [\"18165240\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of PfPKB phosphorylation on invasion not tested\", \"Phosphosites not mapped in this study\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Identifying the kinases acting on the motor, GAP45 was established as a CDPK1 substrate with phosphorylation detectable in parasite lysates.\",\n      \"evidence\": \"In vitro kinase assay with recombinant PfCDPK1 and mass spectrometry of phosphopeptides from parasite lysates\",\n      \"pmids\": [\"18768477\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological role of CDPK1 phosphorylation of GAP45 not established\", \"Only two sites identified at this stage\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"The full CDPK1 phosphosite repertoire on GAP45 was mapped and shown to alter its proteolytic and substrate properties, refining the picture of regulated modification.\",\n      \"evidence\": \"In vitro PfCDPK1 phosphorylation, nano-UPLC-MS/MS with IMAC enrichment, and synthetic phosphopeptide assays\",\n      \"pmids\": [\"19549500\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vitro mapping did not confirm all nine sites are used in vivo\", \"Downstream effect on motor function untested\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Whether glideosome assembly is static or regulated was addressed pharmacologically, showing kinase activity influences GAP45 isoform distribution and complex integrity while cADPR calcium release does not.\",\n      \"evidence\": \"Pharmacological inhibition (cADPR inhibitors, staurosporine), immunoprecipitation, and isoform analysis in P. falciparum\",\n      \"pmids\": [\"19576251\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Staurosporine is nonspecific and did not identify the responsible kinase\", \"Link between isoform shift and invasion outcome not established\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"The domain architecture underlying GAP45's bridging function was defined, assigning C-terminal motor recruitment and N-terminal pellicle-integrity roles, with cross-genera complementation confirming conserved function.\",\n      \"evidence\": \"Conditional knockdown/deletion, domain mutagenesis, transgenera complementation, and immunofluorescence\",\n      \"pmids\": [\"20951968\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Egress requirement in P. falciparum not directly tested here\", \"Structural basis of C-terminal MLC1-MyoA recruitment not resolved\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Complex membership was corroborated from the GAP50 anchor side, confirming GAP45 and MTIP are co-recruited to the IMC.\",\n      \"evidence\": \"Immunoprecipitation of GFP-tagged GAP50 with photobleaching and immunofluorescence in P. falciparum\",\n      \"pmids\": [\"21239623\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not determine assembly order of components\", \"Direct GAP45-GAP50 contact not resolved\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Whether phosphorylation controls GAP45 assembly/localization was tested directly, and phosphosite mutagenesis showed it does not, decoupling modification from trafficking; in parallel PLC/calcium and PKA inputs were mapped onto specific serines.\",\n      \"evidence\": \"GFP-tagging and live imaging, in vitro kinase assays, site-directed mutagenesis, PLC inhibition, and PKA phosphoproteomics in P. falciparum schizonts\",\n      \"pmids\": [\"22479457\", \"22558243\", \"23025827\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional readout of the phosphosite mutants on invasion not resolved\", \"How three kinases are coordinated on GAP45 in vivo unknown\", \"Whether phosphorylation regulates motor force or dynamics untested\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Conditional deletion settled the physiological requirement, showing GAP45 is essential for invasion but dispensable for egress and thereby that the actinomyosin motor is not needed for egress.\",\n      \"evidence\": \"DiCre conditional deletion with invasion/egress assays and electron microscopy in P. falciparum asexual blood stages\",\n      \"pmids\": [\"29970464\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular step of invasion that fails without GAP45 not pinpointed\", \"Did not dissect contributions of individual GAP45 modifications\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"The specific role of N-myristoylation was isolated, revealing it is required for a functional invasion step independent of membrane targeting or glideosome assembly.\",\n      \"evidence\": \"NMT inhibition, Gly-to-Ala myristoylation-site mutagenesis, invasion assays, immunofluorescence, and chemical proteomics in P. falciparum\",\n      \"pmids\": [\"34695132\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"The distinct invasion function conferred by myristoylation not mechanistically defined\", \"Interplay with palmitoylation not addressed\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"The enzyme responsible for GAP45 IMC targeting was identified, showing DHHC2-mediated palmitoylation directs its IMC localization.\",\n      \"evidence\": \"TurboID IMC proteomics, conditional DHHC2 depletion, palmitoylation assay, and immunofluorescence in P. yoelii\",\n      \"pmids\": [\"35775739\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Shown in P. yoelii, not directly confirmed for the P. falciparum ortholog\", \"Whether DHHC2 loss phenocopies GAP45 mislocalization on invasion untested\"],\n      \"attribution\": [{\"species\": \"Plasmodium yoelii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"A determinant of GAP45 steady-state abundance was found, with GAP40 required to stabilize GAP45 protein levels within the glideosome.\",\n      \"evidence\": \"Conditional knockdown of PfGAP40, co-immunoprecipitation, and western blotting in P. falciparum\",\n      \"pmids\": [\"37249423\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of GAP40-dependent stabilization unknown\", \"Whether reduced GAP45 fully accounts for GAP40 knockdown phenotype not resolved\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The precise molecular step of invasion that requires GAP45 N-myristoylation, and how multi-kinase phosphorylation is integrated to regulate motor function, remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of the GAP45-anchored motor at the pellicle\", \"Functional output of the mapped phosphosites on motor force/dynamics undefined\", \"Molecular function distinguishing myristoylation from palmitoylation in invasion unknown\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005515\", \"supporting_discovery_ids\": [1, 6, 14, 13]},\n      {\"term_id\": \"GO:0019706\", \"supporting_discovery_ids\": [0, 11]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [6]},\n      {\"term_id\": \"GO:0031982\", \"supporting_discovery_ids\": [6, 7, 12]},\n      {\"term_id\": \"GO:0031225\", \"supporting_discovery_ids\": [0, 6]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0044409\", \"supporting_discovery_ids\": [10, 6, 11]},\n      {\"term_id\": \"GO:0071345\", \"supporting_discovery_ids\": [2, 8]}\n    ],\n    \"complexes\": [\n      \"Glideosome (GAP45\\u2013GAP50\\u2013MyoA/PfMyoA\\u2013MTIP/MLC1\\u2013GAP40)\"\n    ],\n    \"partners\": [\n      \"PfGAP50\",\n      \"PfMyoA\",\n      \"MTIP/MLC1\",\n      \"PfGAP40\",\n      \"PfCDPK1 (kinase)\",\n      \"PfPKB (kinase)\",\n      \"PfPKA (kinase)\",\n      \"DHHC2 (palmitoyl-acyl-transferase, P. yoelii)\",\n      \"NMT (N-myristoyltransferase)\"\n    ],\n    \"other_free_text\": [\n      \"GAP45 bridges the plasma membrane and inner membrane complex, with C-terminal recruitment of the MyoA/MLC1 motor and N-terminal acylation plus coiled-coil maintaining pellicle integrity [#6].\",\n      \"N-myristoylation is dispensable for localization and glideosome assembly but essential for a functional invasion step [#11].\",\n      \"DHHC2-dependent palmitoylation directs IMC localization, demonstrated in the P. yoelii ortholog [#12].\",\n      \"GAP45 is phosphorylated at multiple mapped serine/threonine residues (including Ser89, Ser103, Ser149) by CDPK1, PfPKB, and PKA, but these modifications are not required for localization or glideosome assembly [#4, #7, #8, #9].\",\n      \"Conditional deletion shows GAP45 is essential for erythrocyte invasion but dispensable for egress [#10].\"\n    ]\n  }\n}","audit_flag":null,"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_1222700","name":null,"product":"glideosome-associated protein 45","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_1437600","name":null,"product":"glideosome-associated protein 45, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_1441800","name":null,"product":"glideosome-associated protein 45, putative","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"GAP45","evaluation":null}