{"gene":"PF3D7_0204000","run_date":"2026-09-08T16:26:55","timeline":{"discoveries":[{"year":2020,"finding":"During early schizogony in P. falciparum, SMC2 and SMC4 (the condensin core subunits) localize to centromeres but do NOT form condensin I or condensin II complexes at this stage; in mature schizonts and during male gametogenesis, condensin II complex (which includes CAPH2/PF3D7_0204000 as a subunit) forms alongside condensin I. This establishes that CAPH2 participates in the condensin II complex in a stage-specific manner.","method":"Fluorescence microscopy co-localization, chromatin immunoprecipitation sequencing (ChIP-seq), and co-immunoprecipitation to define complex composition at distinct life-cycle stages","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP and ChIP-seq used to define complex membership, but CAPH2 itself was not directly manipulated; complex membership inferred from SMC2/SMC4 pulldowns in a single lab","pmids":["32049018"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2026,"finding":"In P. berghei male gametocytes, CAPH2 (CapH2, condensin-II subunit) co-enriches with ARK1 in co-immunoprecipitation experiments, indicating a physical association between the condensin II complex (including CAPH2) and the Aurora-related kinase ARK1 at this stage.","method":"Co-immunoprecipitation (ARK1-GFP pulldown) followed by mass spectrometry (iBAQ quantification) from male gametocyte lysates","journal":"Nature communications","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single co-IP experiment with n=2 replicates, no functional follow-up specific to CAPH2, interaction detected as part of a broader interactome screen","pmids":["41748607"],"is_preprint":false,"attribution":[{"species":"Plasmodium berghei","strain":""}]}],"current_model":"CAPH2 (PF3D7_0204000) is a subunit of the condensin II complex in Plasmodium, with complex formation occurring in a stage-specific manner (present in mature schizonts and male gametocytes but not early schizogony), and the condensin II complex physically associates with the Aurora-related kinase ARK1 during male gametogenesis."},"narrative":{"mechanistic_narrative":"CAPH2 (PF3D7_0204000) is a subunit of the condensin II complex in Plasmodium, a chromosome-organizing machine whose assembly is developmentally regulated across the parasite life cycle [PMID:32049018]. In P. falciparum, the condensin core subunits SMC2 and SMC4 localize to centromeres during early schizogony but do not assemble into condensin I or condensin II at that stage; the condensin II complex containing CAPH2 forms only in mature schizonts and during male gametogenesis, establishing that CAPH2 participates in condensin II in a stage-specific manner [PMID:32049018]. Beyond its membership in the condensin II complex, no CAPH2-specific molecular function has been characterized in the available corpus; the protein has not been directly manipulated, and its role has been inferred from SMC2/SMC4 pulldowns [PMID:32049018].","teleology":[{"year":2020,"claim":"Whether condensin complexes assemble constitutively or in a developmentally controlled manner in Plasmodium was unresolved; defining when CAPH2-containing condensin II forms clarified that chromosome condensation machinery is staged to specific life-cycle points.","evidence":"Fluorescence co-localization, ChIP-seq, and co-immunoprecipitation across life-cycle stages in P. falciparum","pmids":["32049018"],"confidence":"Medium","gaps":["CAPH2 itself was not directly manipulated; membership inferred from SMC2/SMC4 pulldowns","No functional consequence of CAPH2 loss was tested","The DNA-organizing activity of the CAPH2-containing complex was not directly assayed"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2026,"claim":"Whether condensin II links to cell-cycle kinase signaling during male gametogenesis was unknown; detecting co-enrichment of CAPH2 with the Aurora-related kinase ARK1 placed the complex within a kinase-associated interactome at this stage.","evidence":"ARK1-GFP co-immunoprecipitation with mass spectrometry (iBAQ) from P. berghei male gametocyte lysates","pmids":["41748607"],"confidence":"Low","gaps":["Single co-IP with n=2 replicates and no reciprocal validation or functional follow-up specific to CAPH2","Interaction detected within a broader interactome screen; directness of the CAPH2–ARK1 association is unclear","No evidence that ARK1 phosphorylates or regulates CAPH2"],"attribution":[{"species":"Plasmodium berghei","strain":""}]},{"year":null,"claim":"The intrinsic molecular activity of CAPH2, its requirement for chromosome organization, and the functional meaning of its condensin II membership remain uncharacterized.","evidence":"No direct loss-of-function, structural, or biochemical study of CAPH2 in the available corpus","pmids":[],"confidence":"Low","gaps":["No CAPH2 knockout or knockdown phenotype reported","No structural model or direct DNA-binding/organizing assay for CAPH2","Mechanism of stage-specific condensin II assembly not defined"],"attribution":[]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["condensin II complex (subunit) [#0]"],"partners":["SMC2 (CONDENSIN CORE SUBUNIT, COMPLEX CONTEXT) [#0]","SMC4 (CONDENSIN CORE SUBUNIT, COMPLEX CONTEXT) [#0]","ARK1 / AURORA-RELATED KINASE (CO-IP ASSOCIATION IN P. BERGHEI MALE GAMETOCYTES) [#1]"],"other_free_text":["Condensin II complex containing CAPH2 assembles in a stage-specific manner in P. falciparum: absent in early schizogony, present in mature schizonts and during male gametogenesis [#0].","CAPH2 has not been directly manipulated in the available corpus; its role is inferred from complex-membership evidence only [#0]."]}},"prefetch_data":{},"corpus_meta":[{"pmid":"32049018","id":"PMC_32049018","title":"Plasmodium Condensin Core Subunits SMC2/SMC4 Mediate Atypical Mitosis and Are Essential for Parasite Proliferation and Transmission.","date":"2020","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/32049018","citation_count":30,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"41748607","id":"","title":"Plasmodium ARK1 regulates spindle formation during atypical mitosis and forms a divergent chromosomal passenger complex.","date":"2026","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/41748607","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["CAPH2"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":4699,"output_tokens":720,"usd":0.012448,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":5329,"output_tokens":1546,"usd":0.032648,"stage2_stop_reason":"end_turn"},"total_usd":0.045096,"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\": 2020,\n      \"finding\": \"During early schizogony in P. falciparum, SMC2 and SMC4 (the condensin core subunits) localize to centromeres but do NOT form condensin I or condensin II complexes at this stage; in mature schizonts and during male gametogenesis, condensin II complex (which includes CAPH2/PF3D7_0204000 as a subunit) forms alongside condensin I. This establishes that CAPH2 participates in the condensin II complex in a stage-specific manner.\",\n      \"method\": \"Fluorescence microscopy co-localization, chromatin immunoprecipitation sequencing (ChIP-seq), and co-immunoprecipitation to define complex composition at distinct life-cycle stages\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP and ChIP-seq used to define complex membership, but CAPH2 itself was not directly manipulated; complex membership inferred from SMC2/SMC4 pulldowns in a single lab\",\n      \"pmids\": [\"32049018\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"In P. berghei male gametocytes, CAPH2 (CapH2, condensin-II subunit) co-enriches with ARK1 in co-immunoprecipitation experiments, indicating a physical association between the condensin II complex (including CAPH2) and the Aurora-related kinase ARK1 at this stage.\",\n      \"method\": \"Co-immunoprecipitation (ARK1-GFP pulldown) followed by mass spectrometry (iBAQ quantification) from male gametocyte lysates\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single co-IP experiment with n=2 replicates, no functional follow-up specific to CAPH2, interaction detected as part of a broader interactome screen\",\n      \"pmids\": [\"41748607\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"current_model\": \"CAPH2 (PF3D7_0204000) is a subunit of the condensin II complex in Plasmodium, with complex formation occurring in a stage-specific manner (present in mature schizonts and male gametocytes but not early schizogony), and the condensin II complex physically associates with the Aurora-related kinase ARK1 during male gametogenesis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CAPH2 (PF3D7_0204000) is a subunit of the condensin II complex in Plasmodium, a chromosome-organizing machine whose assembly is developmentally regulated across the parasite life cycle [#0]. In P. falciparum, the condensin core subunits SMC2 and SMC4 localize to centromeres during early schizogony but do not assemble into condensin I or condensin II at that stage; the condensin II complex containing CAPH2 forms only in mature schizonts and during male gametogenesis, establishing that CAPH2 participates in condensin II in a stage-specific manner [#0]. Beyond its membership in the condensin II complex, no CAPH2-specific molecular function has been characterized in the available corpus; the protein has not been directly manipulated, and its role has been inferred from SMC2/SMC4 pulldowns [#0].\",\n  \"teleology\": [\n    {\n      \"year\": 2020,\n      \"claim\": \"Whether condensin complexes assemble constitutively or in a developmentally controlled manner in Plasmodium was unresolved; defining when CAPH2-containing condensin II forms clarified that chromosome condensation machinery is staged to specific life-cycle points.\",\n      \"evidence\": \"Fluorescence co-localization, ChIP-seq, and co-immunoprecipitation across life-cycle stages in P. falciparum\",\n      \"pmids\": [\"32049018\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"CAPH2 itself was not directly manipulated; membership inferred from SMC2/SMC4 pulldowns\",\n        \"No functional consequence of CAPH2 loss was tested\",\n        \"The DNA-organizing activity of the CAPH2-containing complex was not directly assayed\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Whether condensin II links to cell-cycle kinase signaling during male gametogenesis was unknown; detecting co-enrichment of CAPH2 with the Aurora-related kinase ARK1 placed the complex within a kinase-associated interactome at this stage.\",\n      \"evidence\": \"ARK1-GFP co-immunoprecipitation with mass spectrometry (iBAQ) from P. berghei male gametocyte lysates\",\n      \"pmids\": [\"41748607\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"Single co-IP with n=2 replicates and no reciprocal validation or functional follow-up specific to CAPH2\",\n        \"Interaction detected within a broader interactome screen; directness of the CAPH2–ARK1 association is unclear\",\n        \"No evidence that ARK1 phosphorylates or regulates CAPH2\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The intrinsic molecular activity of CAPH2, its requirement for chromosome organization, and the functional meaning of its condensin II membership remain uncharacterized.\",\n      \"evidence\": \"No direct loss-of-function, structural, or biochemical study of CAPH2 in the available corpus\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No CAPH2 knockout or knockdown phenotype reported\",\n        \"No structural model or direct DNA-binding/organizing assay for CAPH2\",\n        \"Mechanism of stage-specific condensin II assembly not defined\"\n      ],\n      \"attribution\": []\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [],\n    \"pathway\": [],\n    \"complexes\": [\n      \"condensin II complex (subunit) [#0]\"\n    ],\n    \"partners\": [\n      \"SMC2 (condensin core subunit, complex context) [#0]\",\n      \"SMC4 (condensin core subunit, complex context) [#0]\",\n      \"ARK1 / Aurora-related kinase (co-IP association in P. berghei male gametocytes) [#1]\"\n    ],\n    \"other_free_text\": [\n      \"Condensin II complex containing CAPH2 assembles in a stage-specific manner in P. falciparum: absent in early schizogony, present in mature schizonts and during male gametogenesis [#0].\",\n      \"CAPH2 has not been directly manipulated in the available corpus; its role is inferred from complex-membership evidence only [#0].\"\n    ]\n  }\n}","audit_flag":{"gene":"PF3D7_0204000","tier":"IDENTITY_CHECK","verdict":"identity unverified","subtype":"names_other_cards","uniprot_band":"","rules_fired":"R12","issue":"No cited paper names this card; 2 of 2 cited papers name other catalogue genes (PF3D7_0509100, PF3D7_0616200, PF3D7_1318400). The summary may describe one of those genes."},"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_0204000","name":null,"product":"condensin-2 complex subunit H2, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_0301800","name":null,"product":"condensin-2 complex subunit H2, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_0417100","name":null,"product":"condensin-2 complex subunit H2, putative","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"CAPH2","evaluation":null}