{"gene":"TG_297640","gene_symbol":"ATS2","run_date":"2026-09-08T15:15:12","timeline":{"discoveries":[{"year":2020,"finding":"TgATS2, an apicoplast acyltransferase, produces (lyso)phosphatidic acid within the apicoplast that is required for recruitment of the dynamin TgDrpC during parasite cytokinesis; disruption of TgATS2 impairs this recruitment and cytokinesis.","method":"Genetic disruption of TgATS2 combined with characterization of TgDrpC recruitment and cytokinesis phenotype","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean genetic disruption with defined cellular phenotype (cytokinesis failure, loss of TgDrpC recruitment) and lipid metabolic readouts, single lab","pmids":["32187549"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2020,"finding":"Disruption of TgATS2 causes parasites to shift lipid acquisition from apicoplast de novo synthesis toward host cell scavenging, demonstrating that TgATS2 activity is a key determinant of the balance between endogenous and exogenous lipid sources.","method":"Genetic disruption of TgATS2 with metabolic lipid profiling and tracking of lipid scavenging versus de novo synthesis","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic KO with metabolic phenotype readout, single lab, two orthogonal approaches (lipid profiling + cellular imaging)","pmids":["32187549"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"current_model":"TgATS2 is an apicoplast-resident acyltransferase that synthesizes (lyso)phosphatidic acid required for recruitment of the dynamin TgDrpC during cytokinesis, and its activity governs the balance between de novo lipid synthesis and host-derived lipid scavenging in Toxoplasma gondii."},"narrative":{"mechanistic_narrative":"TgATS2 is an apicoplast-resident acyltransferase in Toxoplasma gondii that couples organellar lipid synthesis to parasite cell division [PMID:32187549]. Within the apicoplast it produces (lyso)phosphatidic acid, and this lipid product is required for recruitment of the dynamin TgDrpC during cytokinesis; genetic disruption of TgATS2 abolishes TgDrpC recruitment and impairs cytokinesis [PMID:32187549]. TgATS2 activity also sets the balance between endogenous and exogenous lipid sourcing: loss of TgATS2 shifts parasites away from apicoplast de novo synthesis toward scavenging lipids from the host cell [PMID:32187549]. Beyond these findings, no further mechanistic detail — including enzymatic characterization, substrate specificity, or structural basis — has been characterized in the available corpus.","teleology":[{"year":2020,"claim":"It was unknown how apicoplast lipid metabolism is linked to the machinery of parasite division; disruption of TgATS2 showed that its (lyso)phosphatidic acid product is required to recruit the dynamin TgDrpC and drive cytokinesis, establishing a direct lipid-to-division link.","evidence":"Genetic disruption of TgATS2 with analysis of TgDrpC recruitment and cytokinesis phenotype in Toxoplasma gondii","pmids":["32187549"],"confidence":"Medium","gaps":["Enzymatic activity and substrate specificity of TgATS2 not directly reconstituted","Mechanism by which (lyso)phosphatidic acid recruits TgDrpC not defined","Single lab; no reciprocal or structural validation"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2020,"claim":"It was unclear what governs the parasite's reliance on de novo versus host-derived lipids; disruption of TgATS2 shifted lipid acquisition toward host scavenging, establishing TgATS2 as a determinant of the endogenous/exogenous lipid balance.","evidence":"Genetic disruption of TgATS2 with metabolic lipid profiling and tracking of scavenging versus de novo synthesis in Toxoplasma gondii","pmids":["32187549"],"confidence":"Medium","gaps":["Regulatory mechanism controlling the metabolic switch not defined","Whether the scavenging shift is direct or a compensatory response to lost synthesis not resolved"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":null,"claim":"The biochemical enzymology of TgATS2 (substrate specificity, catalytic mechanism, structural basis) and the molecular mechanism linking its lipid product to TgDrpC recruitment remain uncharacterized.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No in vitro reconstitution of acyltransferase activity","No structural model","No direct demonstration of (lyso)phosphatidic acid binding by TgDrpC"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":[],"partners":["TGDRPC (DYNAMIN, RECRUITMENT DEPENDENT ON TGATS2 LIPID PRODUCT)"],"other_free_text":["TgATS2 produces (lyso)phosphatidic acid within the apicoplast [#0].","TgATS2 activity determines the balance between apicoplast de novo lipid synthesis and host-cell lipid scavenging [#1]."]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"32187549","id":"PMC_32187549","title":"Division and Adaptation to Host Environment of Apicomplexan Parasites Depend on Apicoplast Lipid Metabolic Plasticity and Host Organelle Remodeling.","date":"2020","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/32187549","citation_count":46,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":2870,"output_tokens":593,"usd":0.008752,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":5295,"output_tokens":1673,"usd":0.03415,"stage2_stop_reason":"end_turn"},"total_usd":0.042902,"stage1_batch_id":"msgbatch_01S6GjoYQm8LTPUsdhASdqag","stage2_batch_id":"msgbatch_01VX63RTMdBJqsG6gQMqoCjz","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2020,\n      \"finding\": \"TgATS2, an apicoplast acyltransferase, produces (lyso)phosphatidic acid within the apicoplast that is required for recruitment of the dynamin TgDrpC during parasite cytokinesis; disruption of TgATS2 impairs this recruitment and cytokinesis.\",\n      \"method\": \"Genetic disruption of TgATS2 combined with characterization of TgDrpC recruitment and cytokinesis phenotype\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean genetic disruption with defined cellular phenotype (cytokinesis failure, loss of TgDrpC recruitment) and lipid metabolic readouts, single lab\",\n      \"pmids\": [\"32187549\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Disruption of TgATS2 causes parasites to shift lipid acquisition from apicoplast de novo synthesis toward host cell scavenging, demonstrating that TgATS2 activity is a key determinant of the balance between endogenous and exogenous lipid sources.\",\n      \"method\": \"Genetic disruption of TgATS2 with metabolic lipid profiling and tracking of lipid scavenging versus de novo synthesis\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO with metabolic phenotype readout, single lab, two orthogonal approaches (lipid profiling + cellular imaging)\",\n      \"pmids\": [\"32187549\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    }\n  ],\n  \"current_model\": \"TgATS2 is an apicoplast-resident acyltransferase that synthesizes (lyso)phosphatidic acid required for recruitment of the dynamin TgDrpC during cytokinesis, and its activity governs the balance between de novo lipid synthesis and host-derived lipid scavenging in Toxoplasma gondii.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TgATS2 is an apicoplast-resident acyltransferase in Toxoplasma gondii that couples organellar lipid synthesis to parasite cell division [#0]. Within the apicoplast it produces (lyso)phosphatidic acid, and this lipid product is required for recruitment of the dynamin TgDrpC during cytokinesis; genetic disruption of TgATS2 abolishes TgDrpC recruitment and impairs cytokinesis [#0]. TgATS2 activity also sets the balance between endogenous and exogenous lipid sourcing: loss of TgATS2 shifts parasites away from apicoplast de novo synthesis toward scavenging lipids from the host cell [#1]. Beyond these findings, no further mechanistic detail — including enzymatic characterization, substrate specificity, or structural basis — has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2020,\n      \"claim\": \"It was unknown how apicoplast lipid metabolism is linked to the machinery of parasite division; disruption of TgATS2 showed that its (lyso)phosphatidic acid product is required to recruit the dynamin TgDrpC and drive cytokinesis, establishing a direct lipid-to-division link.\",\n      \"evidence\": \"Genetic disruption of TgATS2 with analysis of TgDrpC recruitment and cytokinesis phenotype in Toxoplasma gondii\",\n      \"pmids\": [\"32187549\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Enzymatic activity and substrate specificity of TgATS2 not directly reconstituted\",\n        \"Mechanism by which (lyso)phosphatidic acid recruits TgDrpC not defined\",\n        \"Single lab; no reciprocal or structural validation\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"It was unclear what governs the parasite's reliance on de novo versus host-derived lipids; disruption of TgATS2 shifted lipid acquisition toward host scavenging, establishing TgATS2 as a determinant of the endogenous/exogenous lipid balance.\",\n      \"evidence\": \"Genetic disruption of TgATS2 with metabolic lipid profiling and tracking of scavenging versus de novo synthesis in Toxoplasma gondii\",\n      \"pmids\": [\"32187549\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Regulatory mechanism controlling the metabolic switch not defined\",\n        \"Whether the scavenging shift is direct or a compensatory response to lost synthesis not resolved\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The biochemical enzymology of TgATS2 (substrate specificity, catalytic mechanism, structural basis) and the molecular mechanism linking its lipid product to TgDrpC recruitment remain uncharacterized.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No in vitro reconstitution of acyltransferase activity\",\n        \"No structural model\",\n        \"No direct demonstration of (lyso)phosphatidic acid binding by TgDrpC\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016746\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0009507\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0008654\", \"supporting_discovery_ids\": [0, 1], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0000910\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"TgDrpC (dynamin, recruitment dependent on TgATS2 lipid product)\"],\n    \"other_free_text\": [\n      \"TgATS2 produces (lyso)phosphatidic acid within the apicoplast [#0].\",\n      \"TgATS2 activity determines the balance between apicoplast de novo lipid synthesis and host-cell lipid scavenging [#1].\"\n    ]\n  },\n  \"strain_conflicts\": []\n}","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_297640","name":"ATS2","product":"acyltransferase ATS2","uniprot_acc":"S8FEE8","chromosome":"TGME49_chrII","start_pos":1880818},{"strain":"GT1","gene_id":"TGGT1_297640","name":null,"product":"acyltransferase domain-containing protein","uniprot_acc":null,"chromosome":"TGGT1_chrII","start_pos":1857888},{"strain":"RH88","gene_id":"TGRH88_002410","name":null,"product":"acyltransferase domain-containing protein","uniprot_acc":null,"chromosome":"CM023083","start_pos":2056328},{"strain":"VEG","gene_id":"TGVEG_297640","name":null,"product":"acyltransferase domain-containing protein","uniprot_acc":"V4YNN8","chromosome":"TGVEG_chrII","start_pos":1891906}]}