{"gene":"PF3D7_1304000","run_date":"2026-09-08T19:44:17","timeline":{"discoveries":[{"year":2024,"finding":"CAPH (PF3D7_1304000) is the kleisin subunit of the condensin I complex in P. falciparum and is required for assembly of that complex: inducible knockout of CAPH does not alter expression of PfCAP-G but abolishes its localization to mitotic chromosomes, demonstrating that CAPH is essential for loading/retention of the condensin I complex on chromosomes.","method":"Inducible knockout (conditional KO) with immunofluorescence to assess PfCAP-G localization; interaction confirmed by co-immunoprecipitation with PfCAP-G","journal":"mBio","confidence":"High","confidence_rationale":"Tier 2 / Strong — inducible KO with defined molecular phenotype (loss of partner localization) plus Co-IP interaction, peer-reviewed publication","pmids":["38564676"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2024,"finding":"CAPH (PF3D7_1304000) is dynamically expressed during mitosis with peak expression at the metaphase plate, as determined by live-imaging/immunofluorescence in intraerythrocytic stages.","method":"Immunofluorescence microscopy across erythrocytic cell cycle stages","journal":"mBio","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — single lab, direct localization experiment with temporal resolution across the cell cycle","pmids":["38564676"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2024,"finding":"Loss of CAPH (PF3D7_1304000) results in failed karyokinesis: duplicated centrosomes remain clustered over an unsegmented nuclear mass, forming an abnormal nuclear structure, while mitotic spindle assembly and cytokinesis proceed normally, establishing CAPH as specifically required for nuclear division but not spindle formation or cytokinesis.","method":"Inducible knockout with fluorescence microscopy (centrosome, spindle, and nuclear markers)","journal":"mBio","confidence":"High","confidence_rationale":"Tier 2 / Moderate — inducible KO with multiple orthogonal fluorescence markers distinguishing spindle, centrosome, and nuclear phenotypes in a single rigorous study","pmids":["38564676"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"current_model":"CAPH (PF3D7_1304000) is the kleisin subunit of the P. falciparum condensin I complex that physically interacts with PfCAP-G and is essential for loading/retention of the condensin I complex on mitotic chromosomes; its loss specifically abolishes karyokinesis (while spindle assembly and cytokinesis remain intact), indicating a dedicated role in nuclear division during intraerythrocytic schizogony."},"narrative":{"mechanistic_narrative":"CAPH (PF3D7_1304000) is the kleisin subunit of the condensin I complex in Plasmodium falciparum and functions in nuclear division during intraerythrocytic schizogony [PMID:38564676]. It physically associates with PfCAP-G, and inducible knockout of CAPH does not alter PfCAP-G expression but abolishes its localization to mitotic chromosomes, establishing CAPH as essential for loading and retention of the condensin I complex on chromosomes [PMID:38564676]. Consistent with a mitotic role, CAPH is dynamically expressed across the erythrocytic cell cycle with peak expression at the metaphase plate [PMID:38564676]. Loss of CAPH specifically abolishes karyokinesis — duplicated centrosomes remain clustered over an unsegmented nuclear mass — while mitotic spindle assembly and cytokinesis proceed normally, defining a dedicated requirement for nuclear division rather than spindle formation or cell division [PMID:38564676]. Beyond its role in condensin I assembly and karyokinesis, no further mechanistic detail for CAPH has been characterized in the available corpus.","teleology":[{"year":2024,"claim":"Whether P. falciparum encodes a functional condensin I kleisin that organizes the complex on chromosomes was unresolved; this established CAPH as the kleisin required to load and retain condensin I on mitotic chromosomes.","evidence":"Inducible knockout with immunofluorescence showing loss of PfCAP-G chromosomal localization, plus co-immunoprecipitation confirming interaction with PfCAP-G","pmids":["38564676"],"confidence":"High","gaps":["Direct interactions with other condensin I subunits beyond PfCAP-G not mapped","No structural or biochemical reconstitution of the CAPH-containing complex","Mechanism by which CAPH mediates chromosomal loading not defined"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2024,"claim":"The temporal deployment of CAPH during the cell cycle was unknown; live-imaging showed peak expression at the metaphase plate, linking CAPH function to the mitotic window.","evidence":"Immunofluorescence microscopy across erythrocytic cell cycle stages","pmids":["38564676"],"confidence":"Medium","gaps":["Single-lab observation without independent replication","Regulation driving cell-cycle-dependent expression not identified"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2024,"claim":"Which step of division depends on CAPH was undefined; knockout revealed a specific failure of karyokinesis with intact spindle assembly and cytokinesis, pinpointing a dedicated nuclear-division role.","evidence":"Inducible knockout with orthogonal fluorescence markers for centrosome, spindle, and nucleus","pmids":["38564676"],"confidence":"High","gaps":["Molecular basis linking condensin loading to nuclear segmentation not resolved","Fate of chromosomes within the unsegmented nuclear mass not characterized"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":null,"claim":"It remains unknown how CAPH-dependent condensin I loading is molecularly coupled to chromosome condensation and nuclear segmentation, and what other partners or regulators act at this step.","evidence":"","pmids":[],"confidence":"Low","gaps":["No biochemical or structural definition of the full condensin I complex containing CAPH","No identification of upstream regulators of CAPH loading","Consequences for chromatin architecture during schizogony not measured"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["condensin I complex"],"partners":["PFCAP-G"],"other_free_text":["Kleisin subunit of P. falciparum condensin I; required for loading/retention of condensin I on mitotic chromosomes [#0]","Peak expression at the metaphase plate during intraerythrocytic mitosis [#1]","Specifically required for karyokinesis; spindle assembly and cytokinesis proceed normally in its absence [#2]"]}},"prefetch_data":{},"corpus_meta":[{"pmid":"38564676","id":"PMC_38564676","title":"PfCAP-H is essential for assembly of condensin I complex and karyokinesis during asexual proliferation of Plasmodium falciparum.","date":"2024","source":"mBio","url":"https://pubmed.ncbi.nlm.nih.gov/38564676","citation_count":9,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["CAPH"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"38464281","id":"PMC_38464281","title":"PfCAP-H is essential for assembly of condensin I complex and karyokinesis during asexual proliferation of Plasmodium falciparum.","date":"2024","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/38464281","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["CAPH"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"36040030","id":"","title":"TurboID Identification of Evolutionarily Divergent Components of the Nuclear Pore Complex in the Malaria Model Plasmodium berghei.","date":"2022","source":"mBio","url":"https://pubmed.ncbi.nlm.nih.gov/36040030","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["CAPH"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":5087,"output_tokens":849,"usd":0.013998,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":5581,"output_tokens":1836,"usd":0.036902,"stage2_stop_reason":"end_turn"},"total_usd":0.0509,"stage1_batch_id":"msgbatch_01SRp5hyRc82zNjddxyCCXGk","stage2_batch_id":"msgbatch_01K3BTmBazRo3pRrMvyaPMTY","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2024,\n      \"finding\": \"CAPH (PF3D7_1304000) is the kleisin subunit of the condensin I complex in P. falciparum and is required for assembly of that complex: inducible knockout of CAPH does not alter expression of PfCAP-G but abolishes its localization to mitotic chromosomes, demonstrating that CAPH is essential for loading/retention of the condensin I complex on chromosomes.\",\n      \"method\": \"Inducible knockout (conditional KO) with immunofluorescence to assess PfCAP-G localization; interaction confirmed by co-immunoprecipitation with PfCAP-G\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — inducible KO with defined molecular phenotype (loss of partner localization) plus Co-IP interaction, peer-reviewed publication\",\n      \"pmids\": [\"38564676\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"CAPH (PF3D7_1304000) is dynamically expressed during mitosis with peak expression at the metaphase plate, as determined by live-imaging/immunofluorescence in intraerythrocytic stages.\",\n      \"method\": \"Immunofluorescence microscopy across erythrocytic cell cycle stages\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — single lab, direct localization experiment with temporal resolution across the cell cycle\",\n      \"pmids\": [\"38564676\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Loss of CAPH (PF3D7_1304000) results in failed karyokinesis: duplicated centrosomes remain clustered over an unsegmented nuclear mass, forming an abnormal nuclear structure, while mitotic spindle assembly and cytokinesis proceed normally, establishing CAPH as specifically required for nuclear division but not spindle formation or cytokinesis.\",\n      \"method\": \"Inducible knockout with fluorescence microscopy (centrosome, spindle, and nuclear markers)\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — inducible KO with multiple orthogonal fluorescence markers distinguishing spindle, centrosome, and nuclear phenotypes in a single rigorous study\",\n      \"pmids\": [\"38564676\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"current_model\": \"CAPH (PF3D7_1304000) is the kleisin subunit of the P. falciparum condensin I complex that physically interacts with PfCAP-G and is essential for loading/retention of the condensin I complex on mitotic chromosomes; its loss specifically abolishes karyokinesis (while spindle assembly and cytokinesis remain intact), indicating a dedicated role in nuclear division during intraerythrocytic schizogony.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CAPH (PF3D7_1304000) is the kleisin subunit of the condensin I complex in Plasmodium falciparum and functions in nuclear division during intraerythrocytic schizogony [#0, #2]. It physically associates with PfCAP-G, and inducible knockout of CAPH does not alter PfCAP-G expression but abolishes its localization to mitotic chromosomes, establishing CAPH as essential for loading and retention of the condensin I complex on chromosomes [#0]. Consistent with a mitotic role, CAPH is dynamically expressed across the erythrocytic cell cycle with peak expression at the metaphase plate [#1]. Loss of CAPH specifically abolishes karyokinesis \\u2014 duplicated centrosomes remain clustered over an unsegmented nuclear mass \\u2014 while mitotic spindle assembly and cytokinesis proceed normally, defining a dedicated requirement for nuclear division rather than spindle formation or cell division [#2]. Beyond its role in condensin I assembly and karyokinesis, no further mechanistic detail for CAPH has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2024,\n      \"claim\": \"Whether P. falciparum encodes a functional condensin I kleisin that organizes the complex on chromosomes was unresolved; this established CAPH as the kleisin required to load and retain condensin I on mitotic chromosomes.\",\n      \"evidence\": \"Inducible knockout with immunofluorescence showing loss of PfCAP-G chromosomal localization, plus co-immunoprecipitation confirming interaction with PfCAP-G\",\n      \"pmids\": [\"38564676\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Direct interactions with other condensin I subunits beyond PfCAP-G not mapped\",\n        \"No structural or biochemical reconstitution of the CAPH-containing complex\",\n        \"Mechanism by which CAPH mediates chromosomal loading not defined\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"The temporal deployment of CAPH during the cell cycle was unknown; live-imaging showed peak expression at the metaphase plate, linking CAPH function to the mitotic window.\",\n      \"evidence\": \"Immunofluorescence microscopy across erythrocytic cell cycle stages\",\n      \"pmids\": [\"38564676\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Single-lab observation without independent replication\",\n        \"Regulation driving cell-cycle-dependent expression not identified\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Which step of division depends on CAPH was undefined; knockout revealed a specific failure of karyokinesis with intact spindle assembly and cytokinesis, pinpointing a dedicated nuclear-division role.\",\n      \"evidence\": \"Inducible knockout with orthogonal fluorescence markers for centrosome, spindle, and nucleus\",\n      \"pmids\": [\"38564676\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Molecular basis linking condensin loading to nuclear segmentation not resolved\",\n        \"Fate of chromosomes within the unsegmented nuclear mass not characterized\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unknown how CAPH-dependent condensin I loading is molecularly coupled to chromosome condensation and nuclear segmentation, and what other partners or regulators act at this step.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No biochemical or structural definition of the full condensin I complex containing CAPH\",\n        \"No identification of upstream regulators of CAPH loading\",\n        \"Consequences for chromatin architecture during schizogony not measured\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [\n      {\"term_id\": \"GO:0000793\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [2]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0007076\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0000280\", \"supporting_discovery_ids\": [2]}\n    ],\n    \"complexes\": [\"condensin I complex\"],\n    \"partners\": [\"PfCAP-G\"],\n    \"other_free_text\": [\n      \"Kleisin subunit of P. falciparum condensin I; required for loading/retention of condensin I on mitotic chromosomes [#0]\",\n      \"Peak expression at the metaphase plate during intraerythrocytic mitosis [#1]\",\n      \"Specifically required for karyokinesis; spindle assembly and cytokinesis proceed normally in its absence [#2]\"\n    ]\n  }\n}","audit_flag":null,"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_1304000","name":null,"product":"condensin complex subunit 2, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_1402500","name":null,"product":"condensin complex subunit 2, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_1404200","name":null,"product":"condensin complex subunit 2, putative","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"CAPH","evaluation":null}