{"gene":"PF3D7_1323700","run_date":"2026-09-08T19:44:17","timeline":{"discoveries":[{"year":2009,"finding":"GAPM1 (PF3D7_1323700) is a six-pass transmembrane protein that localizes to the inner membrane complex (IMC) in P. falciparum, where it forms highly SDS-resistant oligomeric complexes. It co-purifies with cytoskeletal alveolin proteins and, to some degree, with the actin-myosin motor complex, supporting a role in anchoring the motor to the cytoskeleton.","method":"Subcellular fractionation, detergent-resistance assays, co-immunoprecipitation, fluorescence microscopy localization","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal co-purification with multiple partners using orthogonal biochemical methods (detergent-resistance, co-IP, fractionation) in the founding study, independently cited and replicated across multiple subsequent works","pmids":["19561073"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2017,"finding":"GAPM1 (PF3D7_1323700) was identified as a binding partner of PhIL1 by co-immunoprecipitation, placing it within a novel PhIL1-associated protein complex that co-exists with but is distinct from the canonical glideosome motor complex in the IMC of P. falciparum and P. berghei.","method":"Co-immunoprecipitation / interactome analysis","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — single co-IP/pulldown approach but independently reported in both P. falciparum and P. berghei contexts within the same study","pmids":["29138437"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""},{"species":"Plasmodium berghei","strain":""}]},{"year":2021,"finding":"Loss-of-function depletion of GAPM1 in P. falciparum results in depolymerization of subpellicular microtubules and compromises parasite shape and structural integrity, establishing a direct role for GAPM1 in maintaining cytoskeletal architecture.","method":"Conditional knockdown with morphological/ultrastructural phenotypic readout (microtubule depolymerization, loss of parasite shape)","journal":"PLoS pathogens","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean conditional knockdown with a specific cellular phenotype (microtubule depolymerization, shape defect) reported in a single study via citation in PMID:34324609 and PMID:39576115","pmids":["34324609"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2023,"finding":"GAPM1 (PF3D7_1323700) co-immunoprecipitates with FBXO1-HA in P. berghei ookinetes, placing it among the pellicle-associated proteins (alongside GAP45, GAP50, CTRP, MyoA, and alveolins) that associate with the SCFFBXO1 ubiquitin ligase complex at the ookinete peripheral membrane.","method":"Co-immunoprecipitation with mass spectrometry (FBXO1-HA pull-down in ookinetes)","journal":"Nature communications","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single co-IP/MS experiment identifying GAPM1 as one of many co-purifying pellicle proteins; no functional follow-up specific to GAPM1","pmids":["36898988"],"is_preprint":false,"attribution":[{"species":"Plasmodium berghei","strain":""}]},{"year":2024,"finding":"In P. berghei, conditional knockdown of IMC1g substantially alters the localization and reduces the expression levels of GAPM1 (along with GAPM2, GAPM3, and IMC1c), demonstrating that GAPM1's proper IMC localization and steady-state abundance depend on the integrity of the PHIL1 complex.","method":"Conditional knockdown of IMC1g followed by immunofluorescence assay and immunoblotting for GAPM1","journal":"mBio","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean conditional knockdown of an upstream component with direct readout of GAPM1 localization and protein level by two orthogonal methods (IFA + immunoblot), single lab","pmids":["39576115"],"is_preprint":false,"attribution":[{"species":"Plasmodium berghei","strain":""}]},{"year":2026,"finding":"GAPM1-smV5 colocalizes with the C-terminal VAB domain of the lipid transfer protein PfVPS13L1 at the nascent IMC ring structure adjacent to the centriolar plaque in P. falciparum schizonts, as shown by ultrastructure expansion microscopy, indicating GAPM1 marks the early IMC membrane at the site of ER-IMC lipid transfer contact.","method":"Ultrastructure expansion microscopy (U-ExM) co-localization of GAPM1-smV5 with mCherry-VAB domain of PfVPS13L1","journal":"Nature communications","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single co-localization imaging experiment; no functional manipulation of GAPM1 itself; GAPM1 used as an IMC marker rather than the subject of mechanistic interrogation","pmids":["41904125"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2018,"finding":"GAPM1 was absent from MyoA-GFP immunoprecipitates in P. falciparum schizonts, a result attributed to its extreme detergent-resistance; GAPM2 and GAPM3 (but not GAPM1) co-purified with MyoA under standard conditions.","method":"Co-immunoprecipitation of MyoA-GFP followed by LC-MS/MS","journal":"The Journal of biological chemistry","confidence":"Low","confidence_rationale":"Tier 3 / Weak — negative result for GAPM1 specifically; single experiment, authors attribute absence to biochemical properties rather than lack of association","pmids":["28893907"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":"3D7"}]}],"current_model":"GAPM1 (PF3D7_1323700) is a six-pass transmembrane protein of the inner membrane complex (IMC) in Plasmodium falciparum that forms highly SDS-resistant oligomeric complexes, co-purifies with both alveolin cytoskeletal proteins and the actin-myosin glideosome motor, participates in a PhIL1-associated sub-complex distinct from the canonical glideosome, and is required for maintaining subpellicular microtubule integrity and parasite shape — with its proper IMC localization depending on the broader PHIL1 complex scaffold."},"narrative":{"mechanistic_narrative":"GAPM1 (PF3D7_1323700) is a six-pass transmembrane protein of the inner membrane complex (IMC) in Plasmodium falciparum that couples the alveolin cytoskeleton to the actin-myosin glideosome motor and maintains subpellicular structural integrity [PMID:19561073, PMID:34324609]. Biochemically it forms highly SDS-resistant oligomeric complexes and co-purifies with alveolin cytoskeletal proteins and, more weakly, with the actin-myosin motor, consistent with a role anchoring the motor to the pellicular cytoskeleton [PMID:19561073]. Rather than being a canonical glideosome subunit, GAPM1 is a component of a distinct PhIL1-associated sub-complex within the IMC [PMID:29138437], and its correct IMC localization and steady-state abundance depend on the integrity of this PHIL1 complex scaffold, as shown in P. berghei where knockdown of IMC1g mislocalizes and destabilizes GAPM1 [PMID:39576115]. Functionally, depletion of GAPM1 in P. falciparum causes depolymerization of subpellicular microtubules and loss of parasite shape, establishing a direct requirement for GAPM1 in cytoskeletal architecture [PMID:34324609]. Beyond these findings, no catalytic activity or direct molecular mechanism of membrane–cytoskeleton coupling for GAPM1 has been characterized in the available corpus.","teleology":[{"year":2009,"claim":"Before this work it was unclear how the glideosome motor is anchored to the pellicle; identifying GAPM1 as a multi-pass IMC membrane protein that co-purifies with alveolins and the motor established it as a candidate membrane-cytoskeleton link.","evidence":"Subcellular fractionation, detergent-resistance assays, co-IP and fluorescence localization in P. falciparum","pmids":["19561073"],"confidence":"High","gaps":["Direct binding interface between GAPM1 and alveolins or motor components not defined","Functional consequence of disrupting GAPM1 not tested in this study","Stoichiometry and composition of the SDS-resistant oligomer unresolved"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2017,"claim":"It was unknown whether GAPM1 belongs to the canonical glideosome or a separate assembly; co-IP placed it in a distinct PhIL1-associated complex, refining its molecular context.","evidence":"Co-immunoprecipitation / interactome analysis in P. falciparum and P. berghei","pmids":["29138437"],"confidence":"Medium","gaps":["Single co-IP approach without reciprocal validation for GAPM1 specifically","Whether the PhIL1 interaction is direct or bridged is not established"],"attribution":[{"species":"Plasmodium falciparum","strain":""},{"species":"Plasmodium berghei","strain":""}]},{"year":2018,"claim":"A test of whether GAPM1 associates with the motor under standard conditions returned a negative result, clarifying that its extreme detergent-resistance, rather than absence of association, limits its recovery in motor pulldowns.","evidence":"MyoA-GFP co-IP followed by LC-MS/MS in P. falciparum 3D7 schizonts","pmids":["28893907"],"confidence":"Low","gaps":["Negative result attributed to biochemical properties rather than directly demonstrated","Does not resolve whether GAPM1 physically contacts MyoA at all","Contrasts with sibling GAPM2/GAPM3 co-purification, leaving GAPM1's motor coupling unclear"],"attribution":[{"species":"Plasmodium falciparum","strain":"3D7"}]},{"year":2021,"claim":"The cellular function of GAPM1 was untested until conditional depletion showed subpellicular microtubule depolymerization and shape loss, establishing a direct requirement in maintaining cytoskeletal architecture.","evidence":"Conditional knockdown with morphological/ultrastructural readout in P. falciparum","pmids":["34324609"],"confidence":"Medium","gaps":["Molecular mechanism linking GAPM1 loss to microtubule depolymerization unknown","Whether the defect is direct or secondary to IMC disassembly not resolved","Reported in a single study"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2023,"claim":"Whether GAPM1 associates with other pellicle regulatory machinery was addressed by finding it among proteins co-purifying with the SCFFBXO1 ubiquitin ligase at the ookinete pellicle, extending its interaction context.","evidence":"FBXO1-HA co-IP with mass spectrometry in P. berghei ookinetes","pmids":["36898988"],"confidence":"Low","gaps":["Single co-IP/MS identifying GAPM1 as one of many co-purifying proteins with no GAPM1-specific follow-up","Functional significance of any GAPM1–SCFFBXO1 link untested","Whether GAPM1 is a ubiquitylation substrate unknown"],"attribution":[{"species":"Plasmodium berghei","strain":""}]},{"year":2024,"claim":"The hierarchy governing GAPM1 positioning was unresolved; depleting the upstream PHIL1-complex component IMC1g mislocalized and reduced GAPM1, showing GAPM1's IMC localization and abundance depend on the complex scaffold.","evidence":"Conditional knockdown of IMC1g with IFA and immunoblot readout for GAPM1 in P. berghei","pmids":["39576115"],"confidence":"Medium","gaps":["Whether the effect on GAPM1 is direct or through general IMC destabilization not distinguished","Reciprocal dependence of IMC1g on GAPM1 not tested","Single-lab result"],"attribution":[{"species":"Plasmodium berghei","strain":""}]},{"year":2026,"claim":"The timing and site of GAPM1 incorporation into the IMC was addressed by imaging its colocalization with a lipid transfer protein at the nascent IMC ring, positioning GAPM1 at early IMC membrane assembly adjacent to the centriolar plaque.","evidence":"U-ExM colocalization of GAPM1-smV5 with mCherry-VAB domain of PfVPS13L1 in P. falciparum schizonts","pmids":["41904125"],"confidence":"Low","gaps":["Single colocalization experiment with no functional manipulation of GAPM1","GAPM1 used as an IMC marker rather than the subject of study","No evidence GAPM1 participates in the lipid transfer itself"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":null,"claim":"The molecular basis by which GAPM1 physically couples the IMC membrane to the alveolin/microtubule cytoskeleton and how its loss triggers microtubule depolymerization remain undefined.","evidence":"","pmids":[],"confidence":"Low","gaps":["No direct binding interface or structural model for GAPM1","Mechanism connecting GAPM1 to subpellicular microtubule stability unknown","No reconstitution of the SDS-resistant GAPM1 oligomer"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["PhIL1-associated IMC sub-complex","alveolin/subpellicular cytoskeleton network","SDS-resistant GAPM oligomer"],"partners":["PHIL1","ALVEOLIN CYTOSKELETAL PROTEINS","ACTIN-MYOSIN GLIDEOSOME MOTOR (WEAK)","IMC1G (DEPENDENCE)","SCFFBXO1 PELLICLE-ASSOCIATED PROTEINS (P. BERGHEI OOKINETES)","PFVPS13L1 VAB DOMAIN (COLOCALIZATION)"],"other_free_text":["Six-pass transmembrane protein of the inner membrane complex [#0]","Forms highly SDS-resistant oligomeric complexes, which obscures its recovery in standard motor co-IPs [#0, #6]","Required for subpellicular microtubule integrity and parasite shape in P. falciparum [#2]","Proper IMC localization and abundance depend on the PHIL1 complex scaffold (shown via IMC1g knockdown in P. berghei) [#4]","Marks the nascent IMC ring near the centriolar plaque during schizogony [#5]"]}},"prefetch_data":{},"corpus_meta":[{"pmid":"19561073","id":"PMC_19561073","title":"A novel family of Apicomplexan glideosome-associated proteins with an inner membrane-anchoring role.","date":"2009","source":"The Journal of biological 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complexes. It co-purifies with cytoskeletal alveolin proteins and, to some degree, with the actin-myosin motor complex, supporting a role in anchoring the motor to the cytoskeleton.\",\n      \"method\": \"Subcellular fractionation, detergent-resistance assays, co-immunoprecipitation, fluorescence microscopy localization\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal co-purification with multiple partners using orthogonal biochemical methods (detergent-resistance, co-IP, fractionation) in the founding study, independently cited and replicated across multiple subsequent works\",\n      \"pmids\": [\"19561073\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"GAPM1 (PF3D7_1323700) was identified as a binding partner of PhIL1 by co-immunoprecipitation, placing it within a novel PhIL1-associated protein complex that co-exists with but is distinct from the canonical glideosome motor complex in the IMC of P. falciparum and P. berghei.\",\n      \"method\": \"Co-immunoprecipitation / interactome analysis\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — single co-IP/pulldown approach but independently reported in both P. falciparum and P. berghei contexts within the same study\",\n      \"pmids\": [\"29138437\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"},\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Loss-of-function depletion of GAPM1 in P. falciparum results in depolymerization of subpellicular microtubules and compromises parasite shape and structural integrity, establishing a direct role for GAPM1 in maintaining cytoskeletal architecture.\",\n      \"method\": \"Conditional knockdown with morphological/ultrastructural phenotypic readout (microtubule depolymerization, loss of parasite shape)\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean conditional knockdown with a specific cellular phenotype (microtubule depolymerization, shape defect) reported in a single study via citation in PMID:34324609 and PMID:39576115\",\n      \"pmids\": [\"34324609\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"GAPM1 (PF3D7_1323700) co-immunoprecipitates with FBXO1-HA in P. berghei ookinetes, placing it among the pellicle-associated proteins (alongside GAP45, GAP50, CTRP, MyoA, and alveolins) that associate with the SCFFBXO1 ubiquitin ligase complex at the ookinete peripheral membrane.\",\n      \"method\": \"Co-immunoprecipitation with mass spectrometry (FBXO1-HA pull-down in ookinetes)\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single co-IP/MS experiment identifying GAPM1 as one of many co-purifying pellicle proteins; no functional follow-up specific to GAPM1\",\n      \"pmids\": [\"36898988\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium berghei\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"In P. berghei, conditional knockdown of IMC1g substantially alters the localization and reduces the expression levels of GAPM1 (along with GAPM2, GAPM3, and IMC1c), demonstrating that GAPM1's proper IMC localization and steady-state abundance depend on the integrity of the PHIL1 complex.\",\n      \"method\": \"Conditional knockdown of IMC1g followed by immunofluorescence assay and immunoblotting for GAPM1\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean conditional knockdown of an upstream component with direct readout of GAPM1 localization and protein level by two orthogonal methods (IFA + immunoblot), single lab\",\n      \"pmids\": [\"39576115\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium berghei\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"GAPM1-smV5 colocalizes with the C-terminal VAB domain of the lipid transfer protein PfVPS13L1 at the nascent IMC ring structure adjacent to the centriolar plaque in P. falciparum schizonts, as shown by ultrastructure expansion microscopy, indicating GAPM1 marks the early IMC membrane at the site of ER-IMC lipid transfer contact.\",\n      \"method\": \"Ultrastructure expansion microscopy (U-ExM) co-localization of GAPM1-smV5 with mCherry-VAB domain of PfVPS13L1\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single co-localization imaging experiment; no functional manipulation of GAPM1 itself; GAPM1 used as an IMC marker rather than the subject of mechanistic interrogation\",\n      \"pmids\": [\"41904125\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"GAPM1 was absent from MyoA-GFP immunoprecipitates in P. falciparum schizonts, a result attributed to its extreme detergent-resistance; GAPM2 and GAPM3 (but not GAPM1) co-purified with MyoA under standard conditions.\",\n      \"method\": \"Co-immunoprecipitation of MyoA-GFP followed by LC-MS/MS\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — negative result for GAPM1 specifically; single experiment, authors attribute absence to biochemical properties rather than lack of association\",\n      \"pmids\": [\"28893907\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"3D7\"}]\n    }\n  ],\n  \"current_model\": \"GAPM1 (PF3D7_1323700) is a six-pass transmembrane protein of the inner membrane complex (IMC) in Plasmodium falciparum that forms highly SDS-resistant oligomeric complexes, co-purifies with both alveolin cytoskeletal proteins and the actin-myosin glideosome motor, participates in a PhIL1-associated sub-complex distinct from the canonical glideosome, and is required for maintaining subpellicular microtubule integrity and parasite shape — with its proper IMC localization depending on the broader PHIL1 complex scaffold.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"GAPM1 (PF3D7_1323700) is a six-pass transmembrane protein of the inner membrane complex (IMC) in Plasmodium falciparum that couples the alveolin cytoskeleton to the actin-myosin glideosome motor and maintains subpellicular structural integrity [#0, #2]. Biochemically it forms highly SDS-resistant oligomeric complexes and co-purifies with alveolin cytoskeletal proteins and, more weakly, with the actin-myosin motor, consistent with a role anchoring the motor to the pellicular cytoskeleton [#0]. Rather than being a canonical glideosome subunit, GAPM1 is a component of a distinct PhIL1-associated sub-complex within the IMC [#1], and its correct IMC localization and steady-state abundance depend on the integrity of this PHIL1 complex scaffold, as shown in P. berghei where knockdown of IMC1g mislocalizes and destabilizes GAPM1 [#4]. Functionally, depletion of GAPM1 in P. falciparum causes depolymerization of subpellicular microtubules and loss of parasite shape, establishing a direct requirement for GAPM1 in cytoskeletal architecture [#2]. Beyond these findings, no catalytic activity or direct molecular mechanism of membrane–cytoskeleton coupling for GAPM1 has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2009,\n      \"claim\": \"Before this work it was unclear how the glideosome motor is anchored to the pellicle; identifying GAPM1 as a multi-pass IMC membrane protein that co-purifies with alveolins and the motor established it as a candidate membrane-cytoskeleton link.\",\n      \"evidence\": \"Subcellular fractionation, detergent-resistance assays, co-IP and fluorescence localization in P. falciparum\",\n      \"pmids\": [\"19561073\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Direct binding interface between GAPM1 and alveolins or motor components not defined\",\n        \"Functional consequence of disrupting GAPM1 not tested in this study\",\n        \"Stoichiometry and composition of the SDS-resistant oligomer unresolved\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"It was unknown whether GAPM1 belongs to the canonical glideosome or a separate assembly; co-IP placed it in a distinct PhIL1-associated complex, refining its molecular context.\",\n      \"evidence\": \"Co-immunoprecipitation / interactome analysis in P. falciparum and P. berghei\",\n      \"pmids\": [\"29138437\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Single co-IP approach without reciprocal validation for GAPM1 specifically\",\n        \"Whether the PhIL1 interaction is direct or bridged is not established\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"},\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"A test of whether GAPM1 associates with the motor under standard conditions returned a negative result, clarifying that its extreme detergent-resistance, rather than absence of association, limits its recovery in motor pulldowns.\",\n      \"evidence\": \"MyoA-GFP co-IP followed by LC-MS/MS in P. falciparum 3D7 schizonts\",\n      \"pmids\": [\"28893907\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"Negative result attributed to biochemical properties rather than directly demonstrated\",\n        \"Does not resolve whether GAPM1 physically contacts MyoA at all\",\n        \"Contrasts with sibling GAPM2/GAPM3 co-purification, leaving GAPM1's motor coupling unclear\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"3D7\"}]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"The cellular function of GAPM1 was untested until conditional depletion showed subpellicular microtubule depolymerization and shape loss, establishing a direct requirement in maintaining cytoskeletal architecture.\",\n      \"evidence\": \"Conditional knockdown with morphological/ultrastructural readout in P. falciparum\",\n      \"pmids\": [\"34324609\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Molecular mechanism linking GAPM1 loss to microtubule depolymerization unknown\",\n        \"Whether the defect is direct or secondary to IMC disassembly not resolved\",\n        \"Reported in a single study\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Whether GAPM1 associates with other pellicle regulatory machinery was addressed by finding it among proteins co-purifying with the SCFFBXO1 ubiquitin ligase at the ookinete pellicle, extending its interaction context.\",\n      \"evidence\": \"FBXO1-HA co-IP with mass spectrometry in P. berghei ookinetes\",\n      \"pmids\": [\"36898988\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"Single co-IP/MS identifying GAPM1 as one of many co-purifying proteins with no GAPM1-specific follow-up\",\n        \"Functional significance of any GAPM1–SCFFBXO1 link untested\",\n        \"Whether GAPM1 is a ubiquitylation substrate unknown\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium berghei\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"The hierarchy governing GAPM1 positioning was unresolved; depleting the upstream PHIL1-complex component IMC1g mislocalized and reduced GAPM1, showing GAPM1's IMC localization and abundance depend on the complex scaffold.\",\n      \"evidence\": \"Conditional knockdown of IMC1g with IFA and immunoblot readout for GAPM1 in P. berghei\",\n      \"pmids\": [\"39576115\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Whether the effect on GAPM1 is direct or through general IMC destabilization not distinguished\",\n        \"Reciprocal dependence of IMC1g on GAPM1 not tested\",\n        \"Single-lab result\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium berghei\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"The timing and site of GAPM1 incorporation into the IMC was addressed by imaging its colocalization with a lipid transfer protein at the nascent IMC ring, positioning GAPM1 at early IMC membrane assembly adjacent to the centriolar plaque.\",\n      \"evidence\": \"U-ExM colocalization of GAPM1-smV5 with mCherry-VAB domain of PfVPS13L1 in P. falciparum schizonts\",\n      \"pmids\": [\"41904125\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"Single colocalization experiment with no functional manipulation of GAPM1\",\n        \"GAPM1 used as an IMC marker rather than the subject of study\",\n        \"No evidence GAPM1 participates in the lipid transfer itself\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The molecular basis by which GAPM1 physically couples the IMC membrane to the alveolin/microtubule cytoskeleton and how its loss triggers microtubule depolymerization remain undefined.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No direct binding interface or structural model for GAPM1\",\n        \"Mechanism connecting GAPM1 to subpellicular microtubule stability unknown\",\n        \"No reconstitution of the SDS-resistant GAPM1 oligomer\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005198\", \"supporting_discovery_ids\": [0, 2]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0020039\", \"supporting_discovery_ids\": [0, 1, 4, 5]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0007015\", \"supporting_discovery_ids\": [0, 2]}\n    ],\n    \"complexes\": [\n      \"PhIL1-associated IMC sub-complex\",\n      \"alveolin/subpellicular cytoskeleton network\",\n      \"SDS-resistant GAPM oligomer\"\n    ],\n    \"partners\": [\n      \"PhIL1\",\n      \"alveolin cytoskeletal proteins\",\n      \"actin-myosin glideosome motor (weak)\",\n      \"IMC1g (dependence)\",\n      \"SCFFBXO1 pellicle-associated proteins (P. berghei ookinetes)\",\n      \"PfVPS13L1 VAB domain (colocalization)\"\n    ],\n    \"other_free_text\": [\n      \"Six-pass transmembrane protein of the inner membrane complex [#0]\",\n      \"Forms highly SDS-resistant oligomeric complexes, which obscures its recovery in standard motor co-IPs [#0, #6]\",\n      \"Required for subpellicular microtubule integrity and parasite shape in P. falciparum [#2]\",\n      \"Proper IMC localization and abundance depend on the PHIL1 complex scaffold (shown via IMC1g knockdown in P. berghei) [#4]\",\n      \"Marks the nascent IMC ring near the centriolar plaque during schizogony [#5]\"\n    ]\n  }\n}","audit_flag":null,"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_1323700","name":null,"product":"glideosome associated protein with multiple membrane spans 1","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_1338900","name":null,"product":"glideosome associated protein with multiple membrane spans 1, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_1205100","name":null,"product":"glideosome associated protein with multiple membrane spans 1, putative","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"GAPM1","evaluation":null}