{"gene":"TG_204060","gene_symbol":"STX12","run_date":"2026-09-10T21:09:19","timeline":{"discoveries":[{"year":2020,"finding":"TgStx12 (Stx12) localizes to the endosomal-like compartment in Toxoplasma gondii and is involved in trafficking of proteins to the apical secretory organelles rhoptries and micronemes as well as to the apicoplast.","method":"Conditional ablation/localization studies of SNARE proteins including Stx12 in T. gondii, with functional readout of organelle biogenesis and protein trafficking defects","journal":"mBio","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — conditional genetic ablation with defined organelle-trafficking phenotypes; single lab, multiple organelle readouts but abstract is brief on mechanistic detail","pmids":["33082261"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2021,"finding":"TgStx12 (TgStx10 and TgStx12) localizes to the endosome-like compartment in Toxoplasma gondii, as determined by subcellular localization analysis of SNARE proteins.","method":"Fluorescence localization of tagged SNARE proteins; conditional ablation experiments in T. gondii","journal":"mBio","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct localization by imaging and conditional knockout, single lab, consistent with the 2020 mBio study but distinct experimental series","pmids":["34340555"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"current_model":"TgStx12 is a SNARE protein that localizes to the endosomal-like compartment of Toxoplasma gondii and functions in vesicular trafficking required for the biogenesis of the apical secretory organelles (rhoptries and micronemes) and the apicoplast."},"narrative":{"mechanistic_narrative":"TgStx12 is a SNARE protein of Toxoplasma gondii that localizes to the endosomal-like compartment and functions in the vesicular trafficking required for biogenesis of the parasite's apical secretory organelles [PMID:33082261, PMID:34340555]. Conditional ablation studies show that TgStx12 is needed for correct delivery of proteins to the rhoptries and micronemes as well as to the apicoplast, linking endosomal SNARE-mediated transport to the maturation of these organelles [PMID:33082261]. Beyond this endosomal localization and organelle-trafficking role, no further mechanistic detail — including specific SNARE partners, cognate vesicle populations, or fusion machinery — has been characterized in the available corpus.","teleology":[{"year":2020,"claim":"It was unknown which trafficking factors support biogenesis of the apical secretory organelles; conditional ablation established TgStx12 as an endosomal SNARE required for protein delivery to rhoptries, micronemes, and the apicoplast.","evidence":"conditional genetic ablation and localization of SNARE proteins with organelle-biogenesis and trafficking readouts in T. gondii","pmids":["33082261"],"confidence":"Medium","gaps":["no cognate SNARE partners or fusion complex identified","the specific transport step (donor and acceptor membranes) is not resolved","mechanistic detail beyond phenotypic trafficking defects is limited"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2021,"claim":"A distinct experimental series confirmed that TgStx12, together with TgStx10, resides in the endosome-like compartment, reinforcing its assignment to the endosomal trafficking machinery.","evidence":"fluorescence localization of tagged SNARE proteins and conditional ablation in T. gondii","pmids":["34340555"],"confidence":"Medium","gaps":["functional relationship between TgStx12 and TgStx10 not defined","no reciprocal interaction or complex assembly demonstrated"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":null,"claim":"The molecular SNARE complex in which TgStx12 operates, its cognate vesicle populations, and the precise membrane fusion step it catalyzes remain undefined.","evidence":"","pmids":[],"confidence":"Medium","gaps":["no identified SNARE binding partners","no structural or biochemical reconstitution","mechanism of recruitment to the endosomal compartment unknown"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":[],"partners":["TGSTX10 (CO-LOCALIZING SNARE IN THE ENDOSOME-LIKE COMPARTMENT)"],"other_free_text":["Required for trafficking of proteins to the rhoptries, micronemes, and apicoplast in Toxoplasma gondii [#0]."]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"22153078","id":"PMC_22153078","title":"Sec22b regulates phagosomal maturation and antigen crosspresentation by dendritic cells.","date":"2011","source":"Cell","url":"https://pubmed.ncbi.nlm.nih.gov/22153078","citation_count":253,"is_preprint":false},{"pmid":"33082261","id":"PMC_33082261","title":"The ZIP Code of Vesicle Trafficking in Apicomplexa: SEC1/Munc18 and SNARE Proteins.","date":"2020","source":"mBio","url":"https://pubmed.ncbi.nlm.nih.gov/33082261","citation_count":32,"is_preprint":false},{"pmid":"34340555","id":"PMC_34340555","title":"The Dissection of SNAREs Reveals Key Factors for Vesicular Trafficking to the Endosome-like Compartment and Apicoplast via the Secretory System in Toxoplasma gondii.","date":"2021","source":"mBio","url":"https://pubmed.ncbi.nlm.nih.gov/34340555","citation_count":20,"is_preprint":false},{"pmid":"38270431","id":"PMC_38270431","title":"Apical annuli are specialised sites of post-invasion secretion of dense granules in Toxoplasma.","date":"2024","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/38270431","citation_count":10,"is_preprint":false},{"pmid":"26566590","id":"PMC_26566590","title":"Phosphorylation of αSNAP is Required for Secretory Organelle Biogenesis in Toxoplasma gondii.","date":"2015","source":"Traffic (Copenhagen, Denmark)","url":"https://pubmed.ncbi.nlm.nih.gov/26566590","citation_count":8,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":7639,"output_tokens":561,"usd":0.015666,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":5226,"output_tokens":1391,"usd":0.030453,"stage2_stop_reason":"end_turn"},"total_usd":0.046119,"stage1_batch_id":"msgbatch_018xTxyBPcQFK9jdgubtxgsj","stage2_batch_id":"msgbatch_01UiG5BTaJP7BvKKL6RLeyv2","note":"batch pricing = 50% of standard","corrective_rerun":"2026-09-10 wrong-gene rerun (round-4 rules)","corrective_reason":"paper list: removed papers about other genes"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2020,\n      \"finding\": \"TgStx12 (Stx12) localizes to the endosomal-like compartment in Toxoplasma gondii and is involved in trafficking of proteins to the apical secretory organelles rhoptries and micronemes as well as to the apicoplast.\",\n      \"method\": \"Conditional ablation/localization studies of SNARE proteins including Stx12 in T. gondii, with functional readout of organelle biogenesis and protein trafficking defects\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — conditional genetic ablation with defined organelle-trafficking phenotypes; single lab, multiple organelle readouts but abstract is brief on mechanistic detail\",\n      \"pmids\": [\"33082261\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"TgStx12 (TgStx10 and TgStx12) localizes to the endosome-like compartment in Toxoplasma gondii, as determined by subcellular localization analysis of SNARE proteins.\",\n      \"method\": \"Fluorescence localization of tagged SNARE proteins; conditional ablation experiments in T. gondii\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization by imaging and conditional knockout, single lab, consistent with the 2020 mBio study but distinct experimental series\",\n      \"pmids\": [\"34340555\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"current_model\": \"TgStx12 is a SNARE protein that localizes to the endosomal-like compartment of Toxoplasma gondii and functions in vesicular trafficking required for the biogenesis of the apical secretory organelles (rhoptries and micronemes) and the apicoplast.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TgStx12 is a SNARE protein of Toxoplasma gondii that localizes to the endosomal-like compartment and functions in the vesicular trafficking required for biogenesis of the parasite's apical secretory organelles [#0, #1]. Conditional ablation studies show that TgStx12 is needed for correct delivery of proteins to the rhoptries and micronemes as well as to the apicoplast, linking endosomal SNARE-mediated transport to the maturation of these organelles [#0]. Beyond this endosomal localization and organelle-trafficking role, no further mechanistic detail — including specific SNARE partners, cognate vesicle populations, or fusion machinery — has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2020,\n      \"claim\": \"It was unknown which trafficking factors support biogenesis of the apical secretory organelles; conditional ablation established TgStx12 as an endosomal SNARE required for protein delivery to rhoptries, micronemes, and the apicoplast.\",\n      \"evidence\": \"conditional genetic ablation and localization of SNARE proteins with organelle-biogenesis and trafficking readouts in T. gondii\",\n      \"pmids\": [\"33082261\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"no cognate SNARE partners or fusion complex identified\",\n        \"the specific transport step (donor and acceptor membranes) is not resolved\",\n        \"mechanistic detail beyond phenotypic trafficking defects is limited\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"A distinct experimental series confirmed that TgStx12, together with TgStx10, resides in the endosome-like compartment, reinforcing its assignment to the endosomal trafficking machinery.\",\n      \"evidence\": \"fluorescence localization of tagged SNARE proteins and conditional ablation in T. gondii\",\n      \"pmids\": [\"34340555\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"functional relationship between TgStx12 and TgStx10 not defined\",\n        \"no reciprocal interaction or complex assembly demonstrated\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The molecular SNARE complex in which TgStx12 operates, its cognate vesicle populations, and the precise membrane fusion step it catalyzes remain undefined.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"no identified SNARE binding partners\",\n        \"no structural or biochemical reconstitution\",\n        \"mechanism of recruitment to the endosomal compartment unknown\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005484\", \"supporting_discovery_ids\": [0, 1], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [0, 1], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0016192\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"TgStx10 (co-localizing SNARE in the endosome-like compartment)\"],\n    \"other_free_text\": [\n      \"Required for trafficking of proteins to the rhoptries, micronemes, and apicoplast in Toxoplasma gondii [#0].\"\n    ]\n  },\n  \"strain_conflicts\": []\n}","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_204060","name":"STX12","product":"syntaxin-12","uniprot_acc":"S8GE00","chromosome":"TGME49_chrVIIa","start_pos":2019921},{"strain":"GT1","gene_id":"TGGT1_204060","name":null,"product":"SNARE domain-containing protein","uniprot_acc":null,"chromosome":"TGGT1_chrVIIa","start_pos":1922878},{"strain":"RH88","gene_id":"TGRH88_034950","name":null,"product":"SNARE domain-containing protein","uniprot_acc":null,"chromosome":"CM023088","start_pos":2112353},{"strain":"VEG","gene_id":"TGVEG_204060","name":null,"product":"SNARE domain-containing protein","uniprot_acc":"V4ZLS7","chromosome":"TGVEG_chrVIIa","start_pos":2104163}]}