{"gene":"PF3D7_1103700","run_date":"2026-09-08T12:51:28","timeline":{"discoveries":[{"year":2008,"finding":"Recombinant PfCK2alpha interacts with PfCK2beta1 (CK2beta1/PF3D7_1103700) in vitro, demonstrating that CK2beta1 functions as a regulatory subunit of the P. falciparum CK2 holoenzyme.","method":"In vitro protein interaction assay (recombinant proteins)","journal":"Eukaryotic cell","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — direct in vitro binding assay with recombinant proteins, single lab, single method","pmids":["19114502"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2012,"finding":"Gene disruption experiments show that PfCK2beta1 (CK2beta1/PF3D7_1103700) cannot be disrupted, indicating it is required for completion of the asexual erythrocytic cycle.","method":"Reverse genetics / gene disruption (attempted knockout)","journal":"BMC biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic essentiality established by failed gene disruption, corroborated alongside PfCK2beta2 in same study","pmids":["22293287"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2012,"finding":"Immunofluorescence and electron microscopy of transgenic parasites expressing HA-tagged PfCK2beta1 (CK2beta1/PF3D7_1103700) localized the protein to both cytoplasmic and nuclear compartments during intra-erythrocytic stages.","method":"Immunofluorescence microscopy and electron microscopy of HA-tagged transgenic parasites","journal":"BMC biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct localization by two imaging methods (IFA and EM) on tagged endogenous-like lines, single lab","pmids":["22293287"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2012,"finding":"Affinity purification of HA-PfCK2beta1 (CK2beta1/PF3D7_1103700) followed by mass spectrometry identified interacting proteins enriched in chromatin assembly pathway components, including nucleosome assembly proteins (Naps), histones, and Alba family members, implicating CK2beta1 in chromatin dynamics.","method":"Co-immunoprecipitation of HA-tagged PfCK2beta1 followed by mass spectrometry","journal":"BMC biology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — affinity purification-MS interactome with HA-tagged bait, single lab; pathway enrichment supported by in vitro phosphorylation of substrates by PfCK2alpha","pmids":["22293287"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2017,"finding":"CRISPR/Cas9-mediated tagging confirmed successful integration of HA or HA-TY1 tags at the C-terminus of CK2beta1 (PF3D7_1103700) in P. falciparum 3D7, validated by PCR, DNA sequencing, Western blotting, and immunofluorescence assays.","method":"CRISPR/Cas9 endogenous tagging, PCR, sequencing, Western blot, immunofluorescence","journal":"Parasites & vectors","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — multiple orthogonal validation methods for tagging, single lab; primarily a technical/localization finding","pmids":["29197418"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":"3D7"}]}],"current_model":"CK2beta1 (PF3D7_1103700) is an essential regulatory subunit of the P. falciparum CK2 holoenzyme that binds the catalytic subunit PfCK2alpha in vitro, localizes to both cytoplasmic and nuclear compartments during intra-erythrocytic development, is required for asexual blood-stage parasite survival, and associates with chromatin assembly pathway components including nucleosome assembly proteins, histones, and Alba family members, implicating it in chromatin dynamics."},"narrative":{"mechanistic_narrative":"CK2beta1 (PF3D7_1103700) is an essential regulatory subunit of the Plasmodium falciparum casein kinase II (CK2) holoenzyme, binding the catalytic subunit PfCK2alpha in vitro [PMID:19114502] and being required for completion of the asexual erythrocytic cycle, as its gene cannot be disrupted [PMID:22293287]. During intra-erythrocytic development the protein occupies both cytoplasmic and nuclear compartments [PMID:22293287]. Affinity purification of tagged CK2beta1 recovers an interactome enriched in chromatin assembly components—nucleosome assembly proteins (Naps), histones, and Alba family members—implicating CK2beta1 in chromatin dynamics [PMID:22293287]. Beyond these findings, the precise regulatory contribution of CK2beta1 to CK2 substrate selection and its direct role in chromatin processes have not been further characterized in the available corpus.","teleology":[{"year":2008,"claim":"Establishing whether PF3D7_1103700 acts within the CK2 holoenzyme, the question was whether it physically engages the catalytic subunit; the finding defined it as a bona fide regulatory partner of PfCK2alpha.","evidence":"In vitro protein interaction assay with recombinant PfCK2alpha and PfCK2beta1","pmids":["19114502"],"confidence":"Medium","gaps":["Binding shown only with recombinant proteins in vitro, not in parasite lysate or reconstituted holoenzyme","Stoichiometry and effect of CK2beta1 on PfCK2alpha activity not defined","No structural model of the interaction"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2012,"claim":"To test whether CK2beta1 is dispensable, gene disruption was attempted; the failure to obtain knockouts established it as essential for asexual blood-stage survival.","evidence":"Reverse-genetics gene disruption (attempted knockout) in P. falciparum","pmids":["22293287"],"confidence":"Medium","gaps":["Failed disruption infers but does not prove essentiality; no conditional knockdown to define the essential step","Which specific process CK2beta1 is essential for is not resolved"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2012,"claim":"The subcellular distribution was unknown; imaging of tagged parasites placed CK2beta1 in both cytoplasm and nucleus, indicating dual-compartment function during the intra-erythrocytic cycle.","evidence":"Immunofluorescence and electron microscopy of HA-tagged transgenic parasites","pmids":["22293287"],"confidence":"Medium","gaps":["Compartment-specific function not distinguished","Whether nuclear localization depends on holoenzyme assembly is unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2012,"claim":"To identify the cellular processes CK2beta1 acts within, its interactome was mapped, revealing enrichment for chromatin assembly components and linking CK2beta1 to chromatin dynamics.","evidence":"Co-immunoprecipitation of HA-tagged CK2beta1 followed by mass spectrometry","pmids":["22293287"],"confidence":"Medium","gaps":["Interactions from single affinity purification-MS, not reciprocally validated","Direct phosphorylation of these chromatin factors by the CK2beta1-containing holoenzyme not demonstrated","Functional consequence of the chromatin associations untested"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2017,"claim":"A validated CRISPR/Cas9 endogenous-tagging strategy was established, providing a genetically defined line for studying CK2beta1 in its native context.","evidence":"CRISPR/Cas9 C-terminal tagging in P. falciparum 3D7, validated by PCR, sequencing, Western blot, and immunofluorescence","pmids":["29197418"],"confidence":"Medium","gaps":["Primarily a technical/tagging advance; no new functional mechanism established","Tag effects on holoenzyme assembly not assessed"],"attribution":[{"species":"Plasmodium falciparum","strain":"3D7"}]},{"year":null,"claim":"How CK2beta1 regulates PfCK2alpha activity and substrate choice, and whether its chromatin associations translate into a direct role in nucleosome assembly, remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No conditional depletion to define the essential process","No demonstration that CK2beta1 modulates CK2 activity toward chromatin substrates","No structural or reconstituted-holoenzyme data"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["CK2 holoenzyme (with catalytic subunit PfCK2alpha)"],"partners":["PFCK2ALPHA (CATALYTIC SUBUNIT)","NUCLEOSOME ASSEMBLY PROTEINS (NAPS)","HISTONES","ALBA FAMILY PROTEINS"],"other_free_text":["Essential for completion of the asexual erythrocytic cycle in P. falciparum (gene non-disruptable).","Endogenously HA/HA-TY1 tagged via CRISPR/Cas9 in P. falciparum 3D7 for functional study."]}},"prefetch_data":{},"corpus_meta":[{"pmid":"15479470","id":"PMC_15479470","title":"Protein kinases of the human malaria parasite Plasmodium falciparum: the kinome of a divergent eukaryote.","date":"2004","source":"BMC genomics","url":"https://pubmed.ncbi.nlm.nih.gov/15479470","citation_count":421,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"19114502","id":"PMC_19114502","title":"Functional analysis of protein kinase CK2 of the human malaria parasite Plasmodium falciparum.","date":"2008","source":"Eukaryotic cell","url":"https://pubmed.ncbi.nlm.nih.gov/19114502","citation_count":41,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfCK2beta1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"22293287","id":"PMC_22293287","title":"Involvement of Plasmodium falciparum protein kinase CK2 in the chromatin assembly pathway.","date":"2012","source":"BMC biology","url":"https://pubmed.ncbi.nlm.nih.gov/22293287","citation_count":36,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfCK2beta1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"29197418","id":"PMC_29197418","title":"Tagging to endogenous genes of Plasmodium falciparum using CRISPR/Cas9.","date":"2017","source":"Parasites & vectors","url":"https://pubmed.ncbi.nlm.nih.gov/29197418","citation_count":14,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["CK2beta1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":5068,"output_tokens":1317,"usd":0.017479,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":6207,"output_tokens":2360,"usd":0.045018,"stage2_stop_reason":"end_turn"},"total_usd":0.062497,"stage1_batch_id":"msgbatch_01DisAaTypwmC8QwdMBuePHo","stage2_batch_id":"msgbatch_0184zxZTqxiEfdYYfPMfkqjb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2008,\n      \"finding\": \"Recombinant PfCK2alpha interacts with PfCK2beta1 (CK2beta1/PF3D7_1103700) in vitro, demonstrating that CK2beta1 functions as a regulatory subunit of the P. falciparum CK2 holoenzyme.\",\n      \"method\": \"In vitro protein interaction assay (recombinant proteins)\",\n      \"journal\": \"Eukaryotic cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — direct in vitro binding assay with recombinant proteins, single lab, single method\",\n      \"pmids\": [\"19114502\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Gene disruption experiments show that PfCK2beta1 (CK2beta1/PF3D7_1103700) cannot be disrupted, indicating it is required for completion of the asexual erythrocytic cycle.\",\n      \"method\": \"Reverse genetics / gene disruption (attempted knockout)\",\n      \"journal\": \"BMC biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic essentiality established by failed gene disruption, corroborated alongside PfCK2beta2 in same study\",\n      \"pmids\": [\"22293287\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Immunofluorescence and electron microscopy of transgenic parasites expressing HA-tagged PfCK2beta1 (CK2beta1/PF3D7_1103700) localized the protein to both cytoplasmic and nuclear compartments during intra-erythrocytic stages.\",\n      \"method\": \"Immunofluorescence microscopy and electron microscopy of HA-tagged transgenic parasites\",\n      \"journal\": \"BMC biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization by two imaging methods (IFA and EM) on tagged endogenous-like lines, single lab\",\n      \"pmids\": [\"22293287\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Affinity purification of HA-PfCK2beta1 (CK2beta1/PF3D7_1103700) followed by mass spectrometry identified interacting proteins enriched in chromatin assembly pathway components, including nucleosome assembly proteins (Naps), histones, and Alba family members, implicating CK2beta1 in chromatin dynamics.\",\n      \"method\": \"Co-immunoprecipitation of HA-tagged PfCK2beta1 followed by mass spectrometry\",\n      \"journal\": \"BMC biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — affinity purification-MS interactome with HA-tagged bait, single lab; pathway enrichment supported by in vitro phosphorylation of substrates by PfCK2alpha\",\n      \"pmids\": [\"22293287\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"CRISPR/Cas9-mediated tagging confirmed successful integration of HA or HA-TY1 tags at the C-terminus of CK2beta1 (PF3D7_1103700) in P. falciparum 3D7, validated by PCR, DNA sequencing, Western blotting, and immunofluorescence assays.\",\n      \"method\": \"CRISPR/Cas9 endogenous tagging, PCR, sequencing, Western blot, immunofluorescence\",\n      \"journal\": \"Parasites & vectors\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — multiple orthogonal validation methods for tagging, single lab; primarily a technical/localization finding\",\n      \"pmids\": [\"29197418\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"3D7\"}]\n    }\n  ],\n  \"current_model\": \"CK2beta1 (PF3D7_1103700) is an essential regulatory subunit of the P. falciparum CK2 holoenzyme that binds the catalytic subunit PfCK2alpha in vitro, localizes to both cytoplasmic and nuclear compartments during intra-erythrocytic development, is required for asexual blood-stage parasite survival, and associates with chromatin assembly pathway components including nucleosome assembly proteins, histones, and Alba family members, implicating it in chromatin dynamics.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CK2beta1 (PF3D7_1103700) is an essential regulatory subunit of the Plasmodium falciparum casein kinase II (CK2) holoenzyme, binding the catalytic subunit PfCK2alpha in vitro [#0] and being required for completion of the asexual erythrocytic cycle, as its gene cannot be disrupted [#1]. During intra-erythrocytic development the protein occupies both cytoplasmic and nuclear compartments [#2]. Affinity purification of tagged CK2beta1 recovers an interactome enriched in chromatin assembly components—nucleosome assembly proteins (Naps), histones, and Alba family members—implicating CK2beta1 in chromatin dynamics [#3]. Beyond these findings, the precise regulatory contribution of CK2beta1 to CK2 substrate selection and its direct role in chromatin processes have not been further characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2008,\n      \"claim\": \"Establishing whether PF3D7_1103700 acts within the CK2 holoenzyme, the question was whether it physically engages the catalytic subunit; the finding defined it as a bona fide regulatory partner of PfCK2alpha.\",\n      \"evidence\": \"In vitro protein interaction assay with recombinant PfCK2alpha and PfCK2beta1\",\n      \"pmids\": [\"19114502\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Binding shown only with recombinant proteins in vitro, not in parasite lysate or reconstituted holoenzyme\",\n        \"Stoichiometry and effect of CK2beta1 on PfCK2alpha activity not defined\",\n        \"No structural model of the interaction\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"To test whether CK2beta1 is dispensable, gene disruption was attempted; the failure to obtain knockouts established it as essential for asexual blood-stage survival.\",\n      \"evidence\": \"Reverse-genetics gene disruption (attempted knockout) in P. falciparum\",\n      \"pmids\": [\"22293287\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Failed disruption infers but does not prove essentiality; no conditional knockdown to define the essential step\",\n        \"Which specific process CK2beta1 is essential for is not resolved\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"The subcellular distribution was unknown; imaging of tagged parasites placed CK2beta1 in both cytoplasm and nucleus, indicating dual-compartment function during the intra-erythrocytic cycle.\",\n      \"evidence\": \"Immunofluorescence and electron microscopy of HA-tagged transgenic parasites\",\n      \"pmids\": [\"22293287\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Compartment-specific function not distinguished\",\n        \"Whether nuclear localization depends on holoenzyme assembly is unknown\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"To identify the cellular processes CK2beta1 acts within, its interactome was mapped, revealing enrichment for chromatin assembly components and linking CK2beta1 to chromatin dynamics.\",\n      \"evidence\": \"Co-immunoprecipitation of HA-tagged CK2beta1 followed by mass spectrometry\",\n      \"pmids\": [\"22293287\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Interactions from single affinity purification-MS, not reciprocally validated\",\n        \"Direct phosphorylation of these chromatin factors by the CK2beta1-containing holoenzyme not demonstrated\",\n        \"Functional consequence of the chromatin associations untested\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"A validated CRISPR/Cas9 endogenous-tagging strategy was established, providing a genetically defined line for studying CK2beta1 in its native context.\",\n      \"evidence\": \"CRISPR/Cas9 C-terminal tagging in P. falciparum 3D7, validated by PCR, sequencing, Western blot, and immunofluorescence\",\n      \"pmids\": [\"29197418\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Primarily a technical/tagging advance; no new functional mechanism established\",\n        \"Tag effects on holoenzyme assembly not assessed\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"3D7\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How CK2beta1 regulates PfCK2alpha activity and substrate choice, and whether its chromatin associations translate into a direct role in nucleosome assembly, remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No conditional depletion to define the essential process\",\n        \"No demonstration that CK2beta1 modulates CK2 activity toward chromatin substrates\",\n        \"No structural or reconstituted-holoenzyme data\"\n      ],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0008427\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0019887\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005737\", \"supporting_discovery_ids\": [2]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [2]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0006333\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"complexes\": [\n      \"CK2 holoenzyme (with catalytic subunit PfCK2alpha)\"\n    ],\n    \"partners\": [\n      \"PfCK2alpha (catalytic subunit)\",\n      \"Nucleosome assembly proteins (Naps)\",\n      \"Histones\",\n      \"Alba family proteins\"\n    ],\n    \"other_free_text\": [\n      \"Essential for completion of the asexual erythrocytic cycle in P. falciparum (gene non-disruptable).\",\n      \"Endogenously HA/HA-TY1 tagged via CRISPR/Cas9 in P. falciparum 3D7 for functional study.\"\n    ]\n  }\n}","audit_flag":null,"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_1103700","name":null,"product":"casein kinase II beta chain","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_0943200","name":null,"product":"casein kinase II beta chain, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_0901300","name":null,"product":"casein kinase II beta chain, putative","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"CK2beta1","evaluation":null}