{"gene":"TG_295360","gene_symbol":"IMC18","run_date":"2026-09-08T18:09:50+00:00","timeline":{"discoveries":[{"year":2015,"finding":"IMC18 was identified as a novel component of the Toxoplasma inner membrane complex (IMC) cytoskeletal network using proximity-dependent biotin identification (BioID) with known IMC proteins as bait, localizing it to the IMC suborganellar compartment.","method":"BioID (proximity-dependent biotin identification) in T. gondii, followed by localization studies","journal":"mBio","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — BioID proximity labeling with localization validation, single lab, single method for IMC18 specifically","pmids":["25691595"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2025,"finding":"IMC18 directly binds the microtubule-tethering protein IMT1, as demonstrated by deletion analyses and mutagenesis, placing IMC18 as part of a protein bridge connecting the IMC cytoskeleton to the subpellicular microtubules (SPMTs).","method":"Proximity labeling, deletion analyses, mutagenesis, direct binding assays (Co-IP/pulldown implied by 'binds directly')","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct binding established by deletion/mutagenesis analyses with proximity labeling, single lab, multiple orthogonal methods","pmids":["40768331"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"current_model":"IMC18 is a cytoskeletal component of the Toxoplasma gondii inner membrane complex (IMC) that directly binds the IMC-to-microtubule bridging protein IMT1, thereby participating in the structural linkage between the IMC cytoskeleton and the underlying subpellicular microtubules."},"narrative":{"mechanistic_narrative":"IMC18 is a cytoskeletal component of the Toxoplasma gondii inner membrane complex (IMC) [PMID:25691595]. It contributes to the structural linkage between the IMC cytoskeleton and the underlying subpellicular microtubules by directly binding the microtubule-tethering protein IMT1, positioning IMC18 within a protein bridge that connects the two cytoskeletal systems [PMID:40768331]. Beyond its identification as an IMC network component and its direct interaction with IMT1, no further mechanistic detail has been characterized in the available corpus.","teleology":[{"year":2015,"claim":"Establishing which proteins make up the IMC cytoskeletal network was needed to map the pellicle architecture; BioID from known IMC baits identified IMC18 as a novel resident of this compartment.","evidence":"Proximity-dependent biotin identification (BioID) with known IMC proteins as bait plus localization studies in T. gondii","pmids":["25691595"],"confidence":"Medium","gaps":["Single lab, single-method identification for IMC18 specifically","No functional role or binding partners defined at this stage","No knockout/phenotype data"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2025,"claim":"Whether IMC18 physically couples the IMC to the subpellicular microtubules was unresolved; deletion and mutagenesis analyses showed it binds the microtubule-tethering protein IMT1 directly, placing it in a bridge between the IMC cytoskeleton and the SPMTs.","evidence":"Proximity labeling, deletion analyses, mutagenesis and direct binding assays in T. gondii","pmids":["40768331"],"confidence":"Medium","gaps":["Single lab characterization of the IMC18–IMT1 interaction","Functional consequence of disrupting the bridge for parasite morphology or motility not established here","Structural basis of the direct binding not resolved"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":null,"claim":"The functional requirement of IMC18 for pellicle integrity, cell division, or parasite viability, and the structural details of the IMC18–IMT1 bridge, remain unknown.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No loss-of-function phenotype reported","No structural model of the IMC18–IMT1 interface","Broader interactome of IMC18 within the IMC not defined"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["IMC-to-microtubule bridging complex (IMC18–IMT1)"],"partners":["IMT1"],"other_free_text":["Component of the IMC cytoskeletal network implicated in linking the IMC to subpellicular microtubules [#0, #1]."]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"25691595","id":"PMC_25691595","title":"Novel components of the Toxoplasma inner membrane complex revealed by BioID.","date":"2015","source":"mBio","url":"https://pubmed.ncbi.nlm.nih.gov/25691595","citation_count":148,"is_preprint":false},{"pmid":"40768331","id":"PMC_40768331","title":"Function and interactions of a protein bridge between the inner membrane complex and subpellicular microtubules in Toxoplasma gondii.","date":"2025","source":"Molecular biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/40768331","citation_count":2,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":3494,"output_tokens":557,"usd":0.009418,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":5248,"output_tokens":1417,"usd":0.030832,"stage2_stop_reason":"end_turn"},"total_usd":0.0,"stage1_batch_id":"msgbatch_01WgHz6kceqm573AGLyz57at","stage2_batch_id":"msgbatch_01LK4wDYj5zYquahv7gi9893","note":"batch pricing = 50% of standard","skipped":true},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2015,\n      \"finding\": \"IMC18 was identified as a novel component of the Toxoplasma inner membrane complex (IMC) cytoskeletal network using proximity-dependent biotin identification (BioID) with known IMC proteins as bait, localizing it to the IMC suborganellar compartment.\",\n      \"method\": \"BioID (proximity-dependent biotin identification) in T. gondii, followed by localization studies\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — BioID proximity labeling with localization validation, single lab, single method for IMC18 specifically\",\n      \"pmids\": [\"25691595\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"IMC18 directly binds the microtubule-tethering protein IMT1, as demonstrated by deletion analyses and mutagenesis, placing IMC18 as part of a protein bridge connecting the IMC cytoskeleton to the subpellicular microtubules (SPMTs).\",\n      \"method\": \"Proximity labeling, deletion analyses, mutagenesis, direct binding assays (Co-IP/pulldown implied by 'binds directly')\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct binding established by deletion/mutagenesis analyses with proximity labeling, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"40768331\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    }\n  ],\n  \"current_model\": \"IMC18 is a cytoskeletal component of the Toxoplasma gondii inner membrane complex (IMC) that directly binds the IMC-to-microtubule bridging protein IMT1, thereby participating in the structural linkage between the IMC cytoskeleton and the underlying subpellicular microtubules.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"IMC18 is a cytoskeletal component of the Toxoplasma gondii inner membrane complex (IMC) [#0]. It contributes to the structural linkage between the IMC cytoskeleton and the underlying subpellicular microtubules by directly binding the microtubule-tethering protein IMT1, positioning IMC18 within a protein bridge that connects the two cytoskeletal systems [#1]. Beyond its identification as an IMC network component and its direct interaction with IMT1, no further mechanistic detail has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2015,\n      \"claim\": \"Establishing which proteins make up the IMC cytoskeletal network was needed to map the pellicle architecture; BioID from known IMC baits identified IMC18 as a novel resident of this compartment.\",\n      \"evidence\": \"Proximity-dependent biotin identification (BioID) with known IMC proteins as bait plus localization studies in T. gondii\",\n      \"pmids\": [\n        \"25691595\"\n      ],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Single lab, single-method identification for IMC18 specifically\",\n        \"No functional role or binding partners defined at this stage\",\n        \"No knockout/phenotype data\"\n      ],\n      \"attribution\": [\n        {\n          \"species\": \"Toxoplasma gondii\",\n          \"strain\": \"\"\n        }\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Whether IMC18 physically couples the IMC to the subpellicular microtubules was unresolved; deletion and mutagenesis analyses showed it binds the microtubule-tethering protein IMT1 directly, placing it in a bridge between the IMC cytoskeleton and the SPMTs.\",\n      \"evidence\": \"Proximity labeling, deletion analyses, mutagenesis and direct binding assays in T. gondii\",\n      \"pmids\": [\n        \"40768331\"\n      ],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Single lab characterization of the IMC18\\u2013IMT1 interaction\",\n        \"Functional consequence of disrupting the bridge for parasite morphology or motility not established here\",\n        \"Structural basis of the direct binding not resolved\"\n      ],\n      \"attribution\": [\n        {\n          \"species\": \"Toxoplasma gondii\",\n          \"strain\": \"\"\n        }\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The functional requirement of IMC18 for pellicle integrity, cell division, or parasite viability, and the structural details of the IMC18\\u2013IMT1 bridge, remain unknown.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No loss-of-function phenotype reported\",\n        \"No structural model of the IMC18\\u2013IMT1 interface\",\n        \"Broader interactome of IMC18 within the IMC not defined\"\n      ],\n      \"attribution\": [\n        {\n          \"species\": \"Toxoplasma gondii\",\n          \"strain\": \"\"\n        }\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\n        \"term_id\": \"protein binding\",\n        \"supporting_discovery_ids\": [\n          1\n        ],\n        \"attribution\": [\n          {\n            \"species\": \"Toxoplasma gondii\",\n            \"strain\": \"\"\n          }\n        ]\n      }\n    ],\n    \"localization\": [\n      {\n        \"term_id\": \"inner membrane complex\",\n        \"supporting_discovery_ids\": [\n          0\n        ],\n        \"attribution\": [\n          {\n            \"species\": \"Toxoplasma gondii\",\n            \"strain\": \"\"\n          }\n        ]\n      }\n    ],\n    \"pathway\": [],\n    \"complexes\": [\n      \"IMC-to-microtubule bridging complex (IMC18\\u2013IMT1)\"\n    ],\n    \"partners\": [\n      \"IMT1\"\n    ],\n    \"other_free_text\": [\n      \"Component of the IMC cytoskeletal network implicated in linking the IMC to subpellicular microtubules [#0, #1].\"\n    ]\n  },\n  \"strain_conflicts\": []\n}","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_295360","name":"IMC18","product":"inner membrane complex protein IMC18","uniprot_acc":"A0A125YNR8","chromosome":"TGME49_chrIa","start_pos":1807832},{"strain":"GT1","gene_id":"TGGT1_295360","name":null,"product":"hypothetical protein","uniprot_acc":null,"chromosome":"TGGT1_chrIa","start_pos":1791407},{"strain":"RH88","gene_id":"TGRH88_020650","name":null,"product":"unspecified product","uniprot_acc":null,"chromosome":"CM023081","start_pos":1817970},{"strain":"VEG","gene_id":"TGVEG_295360","name":null,"product":"hypothetical protein","uniprot_acc":"A0A0F7UNW4","chromosome":"TGVEG_chrIa","start_pos":1824049}]}