{"gene":"PF3D7_0920500","run_date":"2026-09-08T12:51:27","timeline":{"discoveries":[{"year":1996,"finding":"Recombinant P. falciparum ARF1 (PfARF1) protein was purified with stoichiometric amounts of bound GDP; the protein bound GTP with first-order kinetics (apparent rate constant k' = 0.0145 min⁻¹); and it stimulated cholera-toxin-catalyzed ADP-ribosyltransferase activity in a reaction dependent on dimyristoylglycerophosphocholine and cholate, establishing it as a functional class I ARF GTPase.","method":"Recombinant protein expression in E. coli, GTP-binding assay, cholera-toxin ADP-ribosyltransferase activity assay","journal":"European journal of biochemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro biochemical reconstitution with multiple orthogonal assays (GTP binding, ADP-ribosyltransferase stimulation) in a single rigorous study","pmids":["8954160"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":1996,"finding":"PfARF1 mRNA (1.8 kb) is developmentally regulated in asexual blood stages, reaching maximum levels during nuclear division toward the end of the intraerythrocytic cycle.","method":"Northern blot analysis","journal":"European journal of biochemistry","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — single direct RNA-level measurement, no functional consequence linked","pmids":["8954160"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2009,"finding":"Recombinant P. falciparum ARF1 activates a unique bifunctional PIP5K (phosphatidylinositol 4-phosphate 5-kinase) in P. falciparum in vitro, linking PfARF1 to the phosphoinositide signalling pathway in the parasite.","method":"In vitro kinase activation assay with recombinant ARF1 and recombinant PfPIP5K","journal":"International journal for parasitology","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — in vitro reconstitution assay, single lab, single study","pmids":["19171150"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2010,"finding":"The crystal structure of P. falciparum ARF1 (PfARF1) was determined in the GDP-bound conformation at 2.5 Å resolution, revealing structural similarities to mammalian class I ARF1 proteins.","method":"X-ray crystallography","journal":"Acta crystallographica. Section F, Structural biology and crystallization communications","confidence":"High","confidence_rationale":"Tier 1 / Moderate — high-resolution crystal structure with direct structural comparison, single rigorous study","pmids":["21045287"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2015,"finding":"PfARF1 (N-myristoylated) co-localises with a Golgi marker in P. falciparum, placing it at the parasite Golgi compartment. When the N-terminus of PfARF1 was combined with palmitoylation and lysine-cluster motifs from PfAK2 in a chimeric protein, the chimera targeted to the parasite plasma membrane (PPM) but was not translocated into the parasitophorous vacuole, indicating that additional features of the PfAK2 N-terminus are required for translocation.","method":"GFP-tagging, fluorescence microscopy co-localisation with Golgi marker, chimeric fusion protein analysis","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — direct imaging with Golgi marker co-localisation and chimeric construct experiments, single lab","pmids":["25909331"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2021,"finding":"PfARF1 was isolated as a PfRab5b-associated protein by co-immunoprecipitation and mass spectrometry. PfARF1 co-localises with PfRab5b adjacent to the ER in early erythrocytic stage parasites, in a distinct ER subdomain from PfRab1b. Expression of an inactive (dominant-negative) PfARF1 mutant specifically inhibited trafficking of N-myristoylated PfAK2 to the parasitophorous vacuole membrane, and also decreased export of the PEXEL-positive protein Rifin, establishing PfARF1 as a regulator of ER exit for both PEXEL-negative and PEXEL-positive cargo.","method":"Co-immunoprecipitation, mass spectrometry, indirect immunofluorescence assay, super-resolution microscopy, expression of active/inactive GTPase mutants","journal":"Frontiers in cellular and infection microbiology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP + MS identification, super-resolution co-localisation, and dominant-negative mutant functional assay, multiple orthogonal methods in a single study","pmids":["33604307"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"current_model":"P. falciparum ARF1 (PfARF1; PF3D7_0920500) is a GDP/GTP-binding small GTPase of the class I ARF family that localises to the Golgi and ER subdomains of the parasite, where it regulates ER export of both PEXEL-negative (PfAK2) and PEXEL-positive (Rifin) cargo in association with PfRab5b, activates the parasite's unique PIP5K to couple vesicular trafficking to phosphoinositide signalling, and its GDP-bound structure has been solved at 2.5 Å resolution."},"narrative":{"mechanistic_narrative":"PF3D7_0920500 encodes a functional class I ADP-ribosylation factor GTPase of Plasmodium falciparum (PfARF1) that governs early secretory trafficking in the intraerythrocytic parasite [PMID:8954160, PMID:33604307]. The recombinant protein purifies with stoichiometrically bound GDP, binds GTP with first-order kinetics, and stimulates cholera-toxin-catalyzed ADP-ribosyltransferase activity, defining it biochemically as a class I ARF [PMID:8954160]; its GDP-bound crystal structure at 2.5 Å resolution shows the fold is conserved relative to mammalian class I ARF1 [PMID:21045287]. N-myristoylated PfARF1 localizes to the parasite Golgi and, in early erythrocytic stages, to an ER subdomain adjacent to and associated with PfRab5b, distinct from the PfRab1b compartment [PMID:25909331, PMID:33604307]. A dominant-negative (inactive) PfARF1 mutant blocks ER exit of the PEXEL-negative cargo PfAK2 to the parasitophorous vacuole membrane and reduces export of the PEXEL-positive protein Rifin, establishing PfARF1 as a regulator of ER exit for both cargo classes [PMID:33604307]. PfARF1 additionally activates the parasite's unique bifunctional PIP5K in vitro, linking it to phosphoinositide signalling [PMID:19171150]. Its mRNA peaks during nuclear division late in the asexual blood-stage cycle [PMID:8954160]. Beyond these findings, the guanine-nucleotide exchange factors, GAPs, and full effector network of PfARF1 have not been characterized in the available corpus.","teleology":[{"year":1996,"claim":"Establishing that the parasite gene product is a bona fide functional GTPase was the necessary first step to treating it as an ARF rather than an annotated ORF.","evidence":"Recombinant expression in E. coli with GTP-binding kinetics and cholera-toxin ADP-ribosyltransferase stimulation assays","pmids":["8954160"],"confidence":"High","gaps":["In vitro assays do not identify the cellular GEF/GAP that cycles PfARF1 in the parasite","No cargo or effector identified at this stage"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":1996,"claim":"Defining when PfARF1 is expressed situated the GTPase within the asexual developmental program, hinting at peak demand for secretory trafficking late in the cycle.","evidence":"Northern blot of 1.8 kb transcript across intraerythrocytic stages","pmids":["8954160"],"confidence":"Medium","gaps":["mRNA timing not linked to protein abundance or to a functional trafficking consequence"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2009,"claim":"Connecting PfARF1 to a parasite lipid kinase addressed whether the GTPase couples membrane trafficking to phosphoinositide signalling.","evidence":"In vitro kinase activation assay with recombinant PfARF1 and recombinant bifunctional PfPIP5K","pmids":["19171150"],"confidence":"Medium","gaps":["Activation shown only in vitro; not validated in parasites","The membrane pool and localization of PIP5K activation relative to PfARF1 not established"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2010,"claim":"Solving the GDP-bound structure provided the molecular framework showing PfARF1 conserves the mammalian class I ARF architecture.","evidence":"X-ray crystallography at 2.5 Å with structural comparison to mammalian ARF1","pmids":["21045287"],"confidence":"High","gaps":["GTP-bound/active conformation not captured","No structure of PfARF1 bound to an effector or GEF"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2015,"claim":"Localizing N-myristoylated PfARF1 to the Golgi and dissecting its N-terminus via chimeras clarified how membrane targeting motifs contribute to cargo trafficking.","evidence":"GFP-tagging, fluorescence co-localisation with a Golgi marker, and chimeric fusion constructs combining PfARF1 and PfAK2 motifs","pmids":["25909331"],"confidence":"Medium","gaps":["Chimera reached the plasma membrane but not the parasitophorous vacuole, so the full PfAK2 translocation determinants remain undefined","Golgi localization based on single-lab imaging"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2021,"claim":"Placing PfARF1 in a PfRab5b-associated ER subdomain and showing a dominant-negative mutant blocks cargo export defined its role as a regulator of ER exit for both PEXEL-negative and PEXEL-positive proteins.","evidence":"Co-IP/mass spectrometry, super-resolution immunofluorescence, and active/inactive GTPase mutant expression in P. falciparum","pmids":["33604307"],"confidence":"High","gaps":["Whether PfARF1 and PfRab5b act as a direct complex or in parallel steps not resolved","Mechanism by which the same GTPase handles distinct PEXEL-positive and PEXEL-negative cargo not defined"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":null,"claim":"The regulatory machinery (GEFs, GAPs) and the complete effector/cargo repertoire that couple PfARF1's nucleotide cycle to specific trafficking and phosphoinositide outputs remain unknown.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No PfARF1 GEF or GAP identified in the corpus","In vivo PIP5K activation and its trafficking consequences not linked","Structural basis of effector selection unresolved"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":[],"partners":["PFRAB5B","PFPIP5K","PFAK2 (CARGO)","RIFIN (CARGO)"],"other_free_text":["N-myristoylated class I ARF GTPase of P. falciparum; GDP-bound crystal structure solved at 2.5 Å [#3].","mRNA peaks during nuclear division late in the asexual intraerythrocytic cycle [#1].","Dominant-negative mutant impairs ER exit of PEXEL-negative PfAK2 and reduces export of PEXEL-positive Rifin [#5]."]}},"prefetch_data":{},"corpus_meta":[{"pmid":"8954160","id":"PMC_8954160","title":"Isolation, expression and characterization of the gene for an ADP-ribosylation factor from the human malaria parasite, Plasmodium falciparum.","date":"1996","source":"European journal of biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/8954160","citation_count":40,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ADP-ribosylation factor","ADP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19171150","id":"PMC_19171150","title":"A unique phosphatidylinositol 4-phosphate 5-kinase is activated by ADP-ribosylation factor in Plasmodium falciparum.","date":"2009","source":"International journal for parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/19171150","citation_count":36,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ADP-ribosylation factor","ADP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"25909331","id":"PMC_25909331","title":"Alternative Protein Secretion in the Malaria Parasite Plasmodium falciparum.","date":"2015","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/25909331","citation_count":23,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ADP-ribosylation factor","ADP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"11555294","id":"PMC_11555294","title":"A point mutation in an unusual Sec7 domain is linked to brefeldin A resistance in a Plasmodium falciparum line generated by drug selection.","date":"2001","source":"Molecular microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/11555294","citation_count":21,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ADP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"6307262","id":"PMC_6307262","title":"ADP-ribosyltransferase in Plasmodium (malaria parasites).","date":"1983","source":"The Biochemical journal","url":"https://pubmed.ncbi.nlm.nih.gov/6307262","citation_count":16,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ADP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"9247933","id":"PMC_9247933","title":"Identification and characterization of an ADP-ribosylation factor in Plasmodium falciparum.","date":"1997","source":"Molecular and biochemical parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/9247933","citation_count":10,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ADP-ribosylation factor","ADP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"9084044","id":"PMC_9084044","title":"Cloning and characterization of Plasmodium falciparum ADP-ribosylation factor and factor-like genes.","date":"1997","source":"Molecular and biochemical parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/9084044","citation_count":10,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ADP-ribosylation factor","ADP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"21045287","id":"PMC_21045287","title":"Structure of Plasmodium falciparum ADP-ribosylation factor 1.","date":"2010","source":"Acta crystallographica. Section F, Structural biology and crystallization communications","url":"https://pubmed.ncbi.nlm.nih.gov/21045287","citation_count":8,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ADP-ribosylation factor","ADP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"38349168","id":"PMC_38349168","title":"Toxoplasma and Plasmodium associate with host Arfs during infection.","date":"2024","source":"mSphere","url":"https://pubmed.ncbi.nlm.nih.gov/38349168","citation_count":1,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ADP"],"competing_organism_flag":true,"competing_organism_match":"Toxoplasma","competing_organism_only":true},{"pmid":"33604307","id":"PMC_33604307","title":"Rab5b-Associated Arf1 GTPase Regulates Export of N-Myristoylated Adenylate Kinase 2 From the Endoplasmic Reticulum in Plasmodium falciparum.","date":"2021","source":"Frontiers in cellular and infection microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/33604307","citation_count":7,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"22102228","id":"PMC_22102228","title":"Structure of the catalytic domain of Plasmodium falciparum ARF GTPase-activating protein (ARFGAP).","date":"2011","source":"Acta crystallographica. Section F, Structural biology and crystallization communications","url":"https://pubmed.ncbi.nlm.nih.gov/22102228","citation_count":2,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ADP-ribosylation factor","ADP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":7576,"output_tokens":1763,"usd":0.024587,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":6765,"output_tokens":2875,"usd":0.05285,"stage2_stop_reason":"end_turn"},"total_usd":0.077437,"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\": 1996,\n      \"finding\": \"Recombinant P. falciparum ARF1 (PfARF1) protein was purified with stoichiometric amounts of bound GDP; the protein bound GTP with first-order kinetics (apparent rate constant k' = 0.0145 min⁻¹); and it stimulated cholera-toxin-catalyzed ADP-ribosyltransferase activity in a reaction dependent on dimyristoylglycerophosphocholine and cholate, establishing it as a functional class I ARF GTPase.\",\n      \"method\": \"Recombinant protein expression in E. coli, GTP-binding assay, cholera-toxin ADP-ribosyltransferase activity assay\",\n      \"journal\": \"European journal of biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro biochemical reconstitution with multiple orthogonal assays (GTP binding, ADP-ribosyltransferase stimulation) in a single rigorous study\",\n      \"pmids\": [\"8954160\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"PfARF1 mRNA (1.8 kb) is developmentally regulated in asexual blood stages, reaching maximum levels during nuclear division toward the end of the intraerythrocytic cycle.\",\n      \"method\": \"Northern blot analysis\",\n      \"journal\": \"European journal of biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — single direct RNA-level measurement, no functional consequence linked\",\n      \"pmids\": [\"8954160\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Recombinant P. falciparum ARF1 activates a unique bifunctional PIP5K (phosphatidylinositol 4-phosphate 5-kinase) in P. falciparum in vitro, linking PfARF1 to the phosphoinositide signalling pathway in the parasite.\",\n      \"method\": \"In vitro kinase activation assay with recombinant ARF1 and recombinant PfPIP5K\",\n      \"journal\": \"International journal for parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — in vitro reconstitution assay, single lab, single study\",\n      \"pmids\": [\"19171150\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"The crystal structure of P. falciparum ARF1 (PfARF1) was determined in the GDP-bound conformation at 2.5 Å resolution, revealing structural similarities to mammalian class I ARF1 proteins.\",\n      \"method\": \"X-ray crystallography\",\n      \"journal\": \"Acta crystallographica. Section F, Structural biology and crystallization communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — high-resolution crystal structure with direct structural comparison, single rigorous study\",\n      \"pmids\": [\"21045287\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"PfARF1 (N-myristoylated) co-localises with a Golgi marker in P. falciparum, placing it at the parasite Golgi compartment. When the N-terminus of PfARF1 was combined with palmitoylation and lysine-cluster motifs from PfAK2 in a chimeric protein, the chimera targeted to the parasite plasma membrane (PPM) but was not translocated into the parasitophorous vacuole, indicating that additional features of the PfAK2 N-terminus are required for translocation.\",\n      \"method\": \"GFP-tagging, fluorescence microscopy co-localisation with Golgi marker, chimeric fusion protein analysis\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — direct imaging with Golgi marker co-localisation and chimeric construct experiments, single lab\",\n      \"pmids\": [\"25909331\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"PfARF1 was isolated as a PfRab5b-associated protein by co-immunoprecipitation and mass spectrometry. PfARF1 co-localises with PfRab5b adjacent to the ER in early erythrocytic stage parasites, in a distinct ER subdomain from PfRab1b. Expression of an inactive (dominant-negative) PfARF1 mutant specifically inhibited trafficking of N-myristoylated PfAK2 to the parasitophorous vacuole membrane, and also decreased export of the PEXEL-positive protein Rifin, establishing PfARF1 as a regulator of ER exit for both PEXEL-negative and PEXEL-positive cargo.\",\n      \"method\": \"Co-immunoprecipitation, mass spectrometry, indirect immunofluorescence assay, super-resolution microscopy, expression of active/inactive GTPase mutants\",\n      \"journal\": \"Frontiers in cellular and infection microbiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP + MS identification, super-resolution co-localisation, and dominant-negative mutant functional assay, multiple orthogonal methods in a single study\",\n      \"pmids\": [\"33604307\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"current_model\": \"P. falciparum ARF1 (PfARF1; PF3D7_0920500) is a GDP/GTP-binding small GTPase of the class I ARF family that localises to the Golgi and ER subdomains of the parasite, where it regulates ER export of both PEXEL-negative (PfAK2) and PEXEL-positive (Rifin) cargo in association with PfRab5b, activates the parasite's unique PIP5K to couple vesicular trafficking to phosphoinositide signalling, and its GDP-bound structure has been solved at 2.5 Å resolution.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"PF3D7_0920500 encodes a functional class I ADP-ribosylation factor GTPase of Plasmodium falciparum (PfARF1) that governs early secretory trafficking in the intraerythrocytic parasite [#0, #5]. The recombinant protein purifies with stoichiometrically bound GDP, binds GTP with first-order kinetics, and stimulates cholera-toxin-catalyzed ADP-ribosyltransferase activity, defining it biochemically as a class I ARF [#0]; its GDP-bound crystal structure at 2.5 Å resolution shows the fold is conserved relative to mammalian class I ARF1 [#3]. N-myristoylated PfARF1 localizes to the parasite Golgi and, in early erythrocytic stages, to an ER subdomain adjacent to and associated with PfRab5b, distinct from the PfRab1b compartment [#4, #5]. A dominant-negative (inactive) PfARF1 mutant blocks ER exit of the PEXEL-negative cargo PfAK2 to the parasitophorous vacuole membrane and reduces export of the PEXEL-positive protein Rifin, establishing PfARF1 as a regulator of ER exit for both cargo classes [#5]. PfARF1 additionally activates the parasite's unique bifunctional PIP5K in vitro, linking it to phosphoinositide signalling [#2]. Its mRNA peaks during nuclear division late in the asexual blood-stage cycle [#1]. Beyond these findings, the guanine-nucleotide exchange factors, GAPs, and full effector network of PfARF1 have not been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 1996,\n      \"claim\": \"Establishing that the parasite gene product is a bona fide functional GTPase was the necessary first step to treating it as an ARF rather than an annotated ORF.\",\n      \"evidence\": \"Recombinant expression in E. coli with GTP-binding kinetics and cholera-toxin ADP-ribosyltransferase stimulation assays\",\n      \"pmids\": [\"8954160\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vitro assays do not identify the cellular GEF/GAP that cycles PfARF1 in the parasite\", \"No cargo or effector identified at this stage\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 1996,\n      \"claim\": \"Defining when PfARF1 is expressed situated the GTPase within the asexual developmental program, hinting at peak demand for secretory trafficking late in the cycle.\",\n      \"evidence\": \"Northern blot of 1.8 kb transcript across intraerythrocytic stages\",\n      \"pmids\": [\"8954160\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"mRNA timing not linked to protein abundance or to a functional trafficking consequence\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Connecting PfARF1 to a parasite lipid kinase addressed whether the GTPase couples membrane trafficking to phosphoinositide signalling.\",\n      \"evidence\": \"In vitro kinase activation assay with recombinant PfARF1 and recombinant bifunctional PfPIP5K\",\n      \"pmids\": [\"19171150\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Activation shown only in vitro; not validated in parasites\", \"The membrane pool and localization of PIP5K activation relative to PfARF1 not established\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Solving the GDP-bound structure provided the molecular framework showing PfARF1 conserves the mammalian class I ARF architecture.\",\n      \"evidence\": \"X-ray crystallography at 2.5 Å with structural comparison to mammalian ARF1\",\n      \"pmids\": [\"21045287\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"GTP-bound/active conformation not captured\", \"No structure of PfARF1 bound to an effector or GEF\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Localizing N-myristoylated PfARF1 to the Golgi and dissecting its N-terminus via chimeras clarified how membrane targeting motifs contribute to cargo trafficking.\",\n      \"evidence\": \"GFP-tagging, fluorescence co-localisation with a Golgi marker, and chimeric fusion constructs combining PfARF1 and PfAK2 motifs\",\n      \"pmids\": [\"25909331\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Chimera reached the plasma membrane but not the parasitophorous vacuole, so the full PfAK2 translocation determinants remain undefined\", \"Golgi localization based on single-lab imaging\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Placing PfARF1 in a PfRab5b-associated ER subdomain and showing a dominant-negative mutant blocks cargo export defined its role as a regulator of ER exit for both PEXEL-negative and PEXEL-positive proteins.\",\n      \"evidence\": \"Co-IP/mass spectrometry, super-resolution immunofluorescence, and active/inactive GTPase mutant expression in P. falciparum\",\n      \"pmids\": [\"33604307\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether PfARF1 and PfRab5b act as a direct complex or in parallel steps not resolved\", \"Mechanism by which the same GTPase handles distinct PEXEL-positive and PEXEL-negative cargo not defined\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The regulatory machinery (GEFs, GAPs) and the complete effector/cargo repertoire that couple PfARF1's nucleotide cycle to specific trafficking and phosphoinositide outputs remain unknown.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No PfARF1 GEF or GAP identified in the corpus\", \"In vivo PIP5K activation and its trafficking consequences not linked\", \"Structural basis of effector selection unresolved\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005525\", \"supporting_discovery_ids\": [0, 3]},\n      {\"term_id\": \"GO:0003924\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0032403\", \"supporting_discovery_ids\": [2, 5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [4]},\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [5]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0006888\", \"supporting_discovery_ids\": [5]},\n      {\"term_id\": \"GO:0016192\", \"supporting_discovery_ids\": [5]},\n      {\"term_id\": \"GO:0046854\", \"supporting_discovery_ids\": [2]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\n      \"PfRab5b\",\n      \"PfPIP5K\",\n      \"PfAK2 (cargo)\",\n      \"Rifin (cargo)\"\n    ],\n    \"other_free_text\": [\n      \"N-myristoylated class I ARF GTPase of P. falciparum; GDP-bound crystal structure solved at 2.5 Å [#3].\",\n      \"mRNA peaks during nuclear division late in the asexual intraerythrocytic cycle [#1].\",\n      \"Dominant-negative mutant impairs ER exit of PEXEL-negative PfAK2 and reduces export of PEXEL-positive Rifin [#5].\"\n    ]\n  }\n}","audit_flag":{"gene":"PF3D7_0920500","tier":"IDENTITY_CHECK","verdict":"identity unverified","subtype":"names_other_cards","uniprot_band":"","rules_fired":"R12","issue":"No cited paper names this card; 5 of 5 cited papers name other catalogue genes (PF3D7_1020900, PF3D7_0816900, PF3D7_0110600). The summary may describe one of those genes."},"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_0920500","name":null,"product":"ADP-ribosylation factor, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_0821400","name":null,"product":"ADP-ribosylation factor, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_0718500","name":null,"product":"ADP-ribosylation factor, putative","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"","evaluation":null}