{"gene":"PF3D7_0303000","run_date":"2026-09-08T16:26:55","timeline":{"discoveries":[{"year":2001,"finding":"P. falciparum NSF (PfNSF/PF3D7_0303000) is an 89-kDa protein that is approximately 90% associated with the particulate (membrane-bound) fraction after parasite homogenization, indicating membrane-bound nature. It is present both within the parasite cell (associated with organelles such as food vacuoles) and exported to vesicular structures in the erythrocyte cytoplasm. Export occurs at the early trophozoite stage and terminates at the merozoite stage, and is inhibited by brefeldin A (IC50 ~9 µM), placing it in the brefeldin A-sensitive secretory pathway.","method":"Subcellular fractionation, immunoblotting with polyclonal antibodies against conserved NSF region, immunofluorescence, immunoelectron microscopy, brefeldin A inhibition assay, Northern blotting, RT-PCR","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — multiple orthogonal methods (fractionation, immunoEM, pharmacological inhibition) in a single focused study; no reconstitution or mutagenesis","pmids":["11278971"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2008,"finding":"NSF (PF3D7_0303000) was identified by LC-MS/MS in a two-step immunoprecipitation (anti-FLAG/anti-PfSUMO) designed to capture sumoylated proteins in P. falciparum blood-stage parasites, suggesting NSF may be a target of sumoylation; the authors note this is consistent with its known cytoplasmic vesicular localization.","method":"Two-step immunoprecipitation followed by LC-MS/MS mass spectrometry","journal":"Cellular microbiology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single pulldown/MS identification with no direct validation that NSF itself is sumoylated; single lab, single method","pmids":["18547337"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"current_model":"P. falciparum NSF (PF3D7_0303000) is an 89-kDa membrane-associated ATPase that localizes to food vacuoles inside the parasite and is exported via a brefeldin A-sensitive pathway into vesicular structures in the erythrocyte cytoplasm during early trophozoite development, implicating it in vesicular trafficking and protein export to the host erythrocyte."},"narrative":{"mechanistic_narrative":"P. falciparum NSF (PF3D7_0303000) is an 89-kDa membrane-associated protein implicated in vesicular trafficking and protein export during blood-stage parasite development [PMID:11278971]. Subcellular fractionation places it predominantly in the particulate fraction, and imaging localizes it both within the parasite—associated with organelles including food vacuoles—and in vesicular structures exported to the host erythrocyte cytoplasm [PMID:11278971]. This export begins at the early trophozoite stage, ceases by the merozoite stage, and is blocked by brefeldin A, situating NSF within the brefeldin A-sensitive secretory pathway [PMID:11278971]. Beyond this localization and pathway assignment, the mechanistic activity of PF3D7_0303000—including any ATPase function, membrane-fusion role, or interacting partners—has not been characterized in the available corpus; a single mass-spectrometry pulldown raises the possibility that it is a sumoylation target, but this remains uncharacterized [PMID:18547337].","teleology":[{"year":2001,"claim":"Establishing whether P. falciparum encodes an NSF-like protein and where it acts addressed how the parasite might drive vesicular trafficking, revealing a membrane-associated protein that is exported into the host erythrocyte via a brefeldin A-sensitive route.","evidence":"Subcellular fractionation, immunoblotting, immunofluorescence, immunoelectron microscopy, and brefeldin A inhibition in blood-stage P. falciparum","pmids":["11278971"],"confidence":"Medium","gaps":["No direct demonstration of ATPase or membrane-fusion activity for PF3D7_0303000","No interacting partners or SNARE substrates identified","No genetic or reconstitution evidence linking NSF to a specific export cargo"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2008,"claim":"A proteomic survey of sumoylation targets asked whether NSF is post-translationally modified, tentatively placing it among candidate sumoylated proteins consistent with its vesicular localization.","evidence":"Two-step anti-FLAG/anti-PfSUMO immunoprecipitation followed by LC-MS/MS in blood-stage parasites","pmids":["18547337"],"confidence":"Low","gaps":["Single pulldown/MS identification with no direct validation that NSF itself is sumoylated","No mapped sumoylation site or functional consequence established","Not independently confirmed"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":null,"claim":"Whether PF3D7_0303000 possesses catalytic (ATPase) activity, engages defined SNARE or trafficking partners, and how its erythrocyte export is regulated remains unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["No biochemical demonstration of enzymatic activity","No validated interactome or complex membership","No loss-of-function phenotype defining its role in export"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":[],"partners":[],"other_free_text":["89-kDa, ~90% membrane-associated (particulate fraction) [#0]","Export begins at early trophozoite stage and terminates at merozoite stage [#0]","Brefeldin A inhibits export with IC50 ~9 µM [#0]","Identified as a candidate sumoylation target by immunoprecipitation/LC-MS/MS, without direct validation [#1]"]}},"prefetch_data":{},"corpus_meta":[{"pmid":"11278971","id":"PMC_11278971","title":"A homologue of N-ethylmaleimide-sensitive factor in the malaria parasite Plasmodium falciparum is exported and localized in vesicular structures in the cytoplasm of infected erythrocytes in the brefeldin A-sensitive pathway.","date":"2001","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/11278971","citation_count":62,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"41025646","id":"","title":"Role of novel mutations in food vacuole transporters beyond K13-mediated artemisinin resistance in Plasmodium falciparum.","date":"2025","source":"Antimicrobial agents and chemotherapy","url":"https://pubmed.ncbi.nlm.nih.gov/41025646","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"34780541","id":"","title":"A conserved guided entry of tail-anchored pathway is involved in the trafficking of a subset of membrane proteins in Plasmodium falciparum.","date":"2021","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/34780541","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"27587718","id":"","title":"Host cell remodeling by pathogens: the exomembrane system in Plasmodium-infected erythrocytes.","date":"2016","source":"FEMS microbiology reviews","url":"https://pubmed.ncbi.nlm.nih.gov/27587718","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"29295911","id":"","title":"ATG8 Is Essential Specifically for an Autophagy-Independent Function in Apicoplast Biogenesis in Blood-Stage Malaria Parasites.","date":"2018","source":"mBio","url":"https://pubmed.ncbi.nlm.nih.gov/29295911","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"41754428","id":"","title":"Mechanisms and Therapeutic Potential of Nutritional Immunity.","date":"2026","source":"Pathogens (Basel, Switzerland)","url":"https://pubmed.ncbi.nlm.nih.gov/41754428","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"29529020","id":"","title":"The Plasmodium falciparum transcriptome in severe malaria reveals altered expression of genes involved in important processes including surface antigen-encoding var genes.","date":"2018","source":"PLoS biology","url":"https://pubmed.ncbi.nlm.nih.gov/29529020","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"27348424","id":"","title":"Plasmodium falciparum Rab1A Localizes to Rhoptries in Schizonts.","date":"2016","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/27348424","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19374766","id":"","title":"A systematic classification of Plasmodium falciparum P-loop NTPases: structural and functional correlation.","date":"2009","source":"Malaria journal","url":"https://pubmed.ncbi.nlm.nih.gov/19374766","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"30704415","id":"","title":"A genome-wide analysis of coatomer protein (COP) subunits of apicomplexan parasites and their evolutionary relationships.","date":"2019","source":"BMC genomics","url":"https://pubmed.ncbi.nlm.nih.gov/30704415","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"18547337","id":"","title":"Identification of a novel post-translational modification in Plasmodium falciparum: protein sumoylation in different cellular compartments.","date":"2008","source":"Cellular microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/18547337","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["NSF"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":13314,"output_tokens":746,"usd":0.025566,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":5398,"output_tokens":1626,"usd":0.03382,"stage2_stop_reason":"end_turn"},"total_usd":0.059386,"stage1_batch_id":"msgbatch_01NE1MTa8x1hW7Lo4tAaNzY1","stage2_batch_id":"msgbatch_0141vaQdeFvbo2q39AinvXM9","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2001,\n      \"finding\": \"P. falciparum NSF (PfNSF/PF3D7_0303000) is an 89-kDa protein that is approximately 90% associated with the particulate (membrane-bound) fraction after parasite homogenization, indicating membrane-bound nature. It is present both within the parasite cell (associated with organelles such as food vacuoles) and exported to vesicular structures in the erythrocyte cytoplasm. Export occurs at the early trophozoite stage and terminates at the merozoite stage, and is inhibited by brefeldin A (IC50 ~9 µM), placing it in the brefeldin A-sensitive secretory pathway.\",\n      \"method\": \"Subcellular fractionation, immunoblotting with polyclonal antibodies against conserved NSF region, immunofluorescence, immunoelectron microscopy, brefeldin A inhibition assay, Northern blotting, RT-PCR\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — multiple orthogonal methods (fractionation, immunoEM, pharmacological inhibition) in a single focused study; no reconstitution or mutagenesis\",\n      \"pmids\": [\"11278971\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"NSF (PF3D7_0303000) was identified by LC-MS/MS in a two-step immunoprecipitation (anti-FLAG/anti-PfSUMO) designed to capture sumoylated proteins in P. falciparum blood-stage parasites, suggesting NSF may be a target of sumoylation; the authors note this is consistent with its known cytoplasmic vesicular localization.\",\n      \"method\": \"Two-step immunoprecipitation followed by LC-MS/MS mass spectrometry\",\n      \"journal\": \"Cellular microbiology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single pulldown/MS identification with no direct validation that NSF itself is sumoylated; single lab, single method\",\n      \"pmids\": [\"18547337\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"current_model\": \"P. falciparum NSF (PF3D7_0303000) is an 89-kDa membrane-associated ATPase that localizes to food vacuoles inside the parasite and is exported via a brefeldin A-sensitive pathway into vesicular structures in the erythrocyte cytoplasm during early trophozoite development, implicating it in vesicular trafficking and protein export to the host erythrocyte.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"P. falciparum NSF (PF3D7_0303000) is an 89-kDa membrane-associated protein implicated in vesicular trafficking and protein export during blood-stage parasite development [#0]. Subcellular fractionation places it predominantly in the particulate fraction, and imaging localizes it both within the parasite—associated with organelles including food vacuoles—and in vesicular structures exported to the host erythrocyte cytoplasm [#0]. This export begins at the early trophozoite stage, ceases by the merozoite stage, and is blocked by brefeldin A, situating NSF within the brefeldin A-sensitive secretory pathway [#0]. Beyond this localization and pathway assignment, the mechanistic activity of PF3D7_0303000—including any ATPase function, membrane-fusion role, or interacting partners—has not been characterized in the available corpus; a single mass-spectrometry pulldown raises the possibility that it is a sumoylation target, but this remains uncharacterized [#1].\",\n  \"teleology\": [\n    {\n      \"year\": 2001,\n      \"claim\": \"Establishing whether P. falciparum encodes an NSF-like protein and where it acts addressed how the parasite might drive vesicular trafficking, revealing a membrane-associated protein that is exported into the host erythrocyte via a brefeldin A-sensitive route.\",\n      \"evidence\": \"Subcellular fractionation, immunoblotting, immunofluorescence, immunoelectron microscopy, and brefeldin A inhibition in blood-stage P. falciparum\",\n      \"pmids\": [\"11278971\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No direct demonstration of ATPase or membrane-fusion activity for PF3D7_0303000\",\n        \"No interacting partners or SNARE substrates identified\",\n        \"No genetic or reconstitution evidence linking NSF to a specific export cargo\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"A proteomic survey of sumoylation targets asked whether NSF is post-translationally modified, tentatively placing it among candidate sumoylated proteins consistent with its vesicular localization.\",\n      \"evidence\": \"Two-step anti-FLAG/anti-PfSUMO immunoprecipitation followed by LC-MS/MS in blood-stage parasites\",\n      \"pmids\": [\"18547337\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"Single pulldown/MS identification with no direct validation that NSF itself is sumoylated\",\n        \"No mapped sumoylation site or functional consequence established\",\n        \"Not independently confirmed\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"Whether PF3D7_0303000 possesses catalytic (ATPase) activity, engages defined SNARE or trafficking partners, and how its erythrocyte export is regulated remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No biochemical demonstration of enzymatic activity\",\n        \"No validated interactome or complex membership\",\n        \"No loss-of-function phenotype defining its role in export\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [\n      {\"term_id\": \"food vacuole\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"host cell cytoplasm (erythrocyte)\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"membrane\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"brefeldin A-sensitive secretory/vesicular trafficking pathway\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"protein export to host erythrocyte\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"complexes\": [],\n    \"partners\": [],\n    \"other_free_text\": [\n      \"89-kDa, ~90% membrane-associated (particulate fraction) [#0]\",\n      \"Export begins at early trophozoite stage and terminates at merozoite stage [#0]\",\n      \"Brefeldin A inhibits export with IC50 ~9 µM [#0]\",\n      \"Identified as a candidate sumoylation target by immunoprecipitation/LC-MS/MS, without direct validation [#1]\"\n    ]\n  }\n}","audit_flag":null,"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_0303000","name":null,"product":"N-ethylmaleimide-sensitive fusion protein","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_0401600","name":null,"product":"N-ethylmaleimide-sensitive fusion protein, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_0840100","name":null,"product":"N-ethylmaleimide-sensitive fusion protein, putative","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"NSF","evaluation":null}