{"gene":"TG_316620","gene_symbol":"CDC20","run_date":"2026-09-08T15:15:13","timeline":{"discoveries":[{"year":2024,"finding":"TgCdc20 was identified as a phosphorylation substrate of the TgCrk4-TgCyc4 CDK complex, as determined by global phosphoproteome analysis of TgCrk4 substrates in Toxoplasma gondii.","method":"Global phosphoproteome analysis (mass spectrometry-based substrate identification)","journal":"The EMBO journal","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single phosphoproteomics screen, no direct in vitro kinase assay or mutagenesis validating TgCdc20 as a bona fide substrate; single lab, single method","pmids":["38600241"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"current_model":"TgCdc20 in Toxoplasma gondii has been identified as a candidate phosphorylation substrate of the cell cycle kinase TgCrk4 (in complex with TgCyc4) based on phosphoproteomic data, suggesting it may be regulated during G2/M cell cycle progression, but no direct mechanistic characterization of TgCdc20's own function has been experimentally established."},"narrative":{"mechanistic_narrative":"In Toxoplasma gondii, TgCdc20 was identified as a candidate phosphorylation substrate of the TgCrk4-TgCyc4 CDK complex in a global phosphoproteome screen, placing it downstream of cell cycle kinase signaling [PMID:38600241]. Beyond this single phosphoproteomic association, no direct mechanistic detail of TgCdc20's own function, partners, or role has been characterized in the available corpus.","teleology":[{"year":2024,"claim":"To map the substrate landscape of the cell cycle kinase TgCrk4, a phosphoproteome screen tested which proteins are phosphorylated in a TgCrk4-dependent manner, and identified TgCdc20 as a candidate substrate — the first mechanistic link placing TgCdc20 under CDK-complex regulation.","evidence":"Global mass spectrometry-based phosphoproteome analysis of TgCrk4-TgCyc4 substrates in Toxoplasma gondii","pmids":["38600241"],"confidence":"Low","gaps":["Single phosphoproteomics screen without in vitro kinase assay or phosphosite mutagenesis to validate TgCdc20 as a bona fide direct substrate","No functional characterization of TgCdc20's own activity, interactors, or cell cycle role","Whether phosphorylation regulates TgCdc20 activity or localization is untested"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":null,"claim":"The molecular function of TgCdc20, its downstream effectors, and the functional consequence of its phosphorylation by TgCrk4-TgCyc4 remain unestablished.","evidence":"No direct functional or mechanistic study present in the corpus","pmids":[],"confidence":"Low","gaps":["No experimental determination of TgCdc20's own biochemical activity","No identified binding partners or substrates of TgCdc20","No genetic or phenotypic evidence for its role in cell cycle progression"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":[],"partners":["TGCRK4-TGCYC4 CDK COMPLEX (KINASE FOR WHICH TGCDC20 IS A CANDIDATE PHOSPHORYLATION SUBSTRATE) [#0]"],"other_free_text":["TgCdc20 identified as a candidate phosphorylation substrate of the TgCrk4-TgCyc4 CDK complex by phosphoproteomics, implying possible regulation during G2/M cell cycle progression [#0]"]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"38600241","id":"PMC_38600241","title":"The Crk4-Cyc4 complex regulates G2/M transition in Toxoplasma gondii.","date":"2024","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/38600241","citation_count":16,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":2923,"output_tokens":359,"usd":0.007077,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":4936,"output_tokens":1040,"usd":0.02534,"stage2_stop_reason":"end_turn"},"total_usd":0.032417,"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\": 2024,\n      \"finding\": \"TgCdc20 was identified as a phosphorylation substrate of the TgCrk4-TgCyc4 CDK complex, as determined by global phosphoproteome analysis of TgCrk4 substrates in Toxoplasma gondii.\",\n      \"method\": \"Global phosphoproteome analysis (mass spectrometry-based substrate identification)\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single phosphoproteomics screen, no direct in vitro kinase assay or mutagenesis validating TgCdc20 as a bona fide substrate; single lab, single method\",\n      \"pmids\": [\"38600241\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"current_model\": \"TgCdc20 in Toxoplasma gondii has been identified as a candidate phosphorylation substrate of the cell cycle kinase TgCrk4 (in complex with TgCyc4) based on phosphoproteomic data, suggesting it may be regulated during G2/M cell cycle progression, but no direct mechanistic characterization of TgCdc20's own function has been experimentally established.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"In Toxoplasma gondii, TgCdc20 was identified as a candidate phosphorylation substrate of the TgCrk4-TgCyc4 CDK complex in a global phosphoproteome screen, placing it downstream of cell cycle kinase signaling [#0]. Beyond this single phosphoproteomic association, no direct mechanistic detail of TgCdc20's own function, partners, or role has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2024,\n      \"claim\": \"To map the substrate landscape of the cell cycle kinase TgCrk4, a phosphoproteome screen tested which proteins are phosphorylated in a TgCrk4-dependent manner, and identified TgCdc20 as a candidate substrate — the first mechanistic link placing TgCdc20 under CDK-complex regulation.\",\n      \"evidence\": \"Global mass spectrometry-based phosphoproteome analysis of TgCrk4-TgCyc4 substrates in Toxoplasma gondii\",\n      \"pmids\": [\"38600241\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"Single phosphoproteomics screen without in vitro kinase assay or phosphosite mutagenesis to validate TgCdc20 as a bona fide direct substrate\",\n        \"No functional characterization of TgCdc20's own activity, interactors, or cell cycle role\",\n        \"Whether phosphorylation regulates TgCdc20 activity or localization is untested\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The molecular function of TgCdc20, its downstream effectors, and the functional consequence of its phosphorylation by TgCrk4-TgCyc4 remain unestablished.\",\n      \"evidence\": \"No direct functional or mechanistic study present in the corpus\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No experimental determination of TgCdc20's own biochemical activity\",\n        \"No identified binding partners or substrates of TgCdc20\",\n        \"No genetic or phenotypic evidence for its role in cell cycle progression\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [],\n    \"pathway\": [],\n    \"complexes\": [],\n    \"partners\": [\"TgCrk4-TgCyc4 CDK complex (kinase for which TgCdc20 is a candidate phosphorylation substrate) [#0]\"],\n    \"other_free_text\": [\n      \"TgCdc20 identified as a candidate phosphorylation substrate of the TgCrk4-TgCyc4 CDK complex by phosphoproteomics, implying possible regulation during G2/M cell cycle progression [#0]\"\n    ]\n  },\n  \"strain_conflicts\": []\n}","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_316620","name":"CDC20","product":"cell division cycle protein CDC20, putative","uniprot_acc":"A0A125YU43","chromosome":"TGME49_chrXI","start_pos":5433190},{"strain":"GT1","gene_id":"TGGT1_316620","name":null,"product":"WD domain, G-beta repeat-containing protein","uniprot_acc":null,"chromosome":"TGGT1_chrXI","start_pos":5379045},{"strain":"RH88","gene_id":"TGRH88_055320","name":null,"product":"WD domain, G-beta repeat-containing protein","uniprot_acc":null,"chromosome":"CM023092","start_pos":5499581},{"strain":"VEG","gene_id":"TGVEG_316620","name":null,"product":"WD domain, G-beta repeat-containing protein","uniprot_acc":"B6K9V2","chromosome":"TGVEG_chrXI","start_pos":5455490}]}