{"gene":"COG1","run_date":"2026-06-09T22:57:18","timeline":{"discoveries":[{"year":1999,"finding":"COG1 (LDLB) encodes an ~110-kDa protein (ldlBp) that localizes to the Golgi apparatus and is required for normal assembly of an ~950-kDa cytosolic complex containing ldlCp (COG2); in ldlB-deficient cells this complex is reduced to ~700 kDa, demonstrating that COG1 is essential for full complex assembly and for Golgi association of ldlCp and normal luminal Golgi processing activities.","method":"Retrovirus-based expression cloning, size-exclusion fractionation of cytosols, complementation of ldlB CHO mutant cells","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — functional complementation, biochemical fractionation, and complex-size analysis in a defined mutant background, replicated conceptually by subsequent COG literature","pmids":["9927668"],"is_preprint":false},{"year":2007,"finding":"The C-terminal 76 amino acids of COG8 are required for direct interaction with COG1; loss of this interaction (via a truncating COG8 mutation) causes secondary COG1 deficiency, prevents assembly of the intact hetero-octameric COG complex, and results in appearance of smaller subcomplexes with defective N- and O-glycosylation and reduced Golgi beta1,4-galactosyltransferase levels. Full-length COG8 transfection restored O-glycosylation, confirming the Cog1–Cog8 interaction is mechanistically required for stable complex formation.","method":"Patient fibroblast analysis, mass spectrometry of glycan structures, protein interaction/co-immunoprecipitation analysis, complementation by transfection of full-length COG8","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (glycan MS, protein-level interaction analysis, functional complementation) in a single rigorous study establishing the Cog1–Cog8 interaction as critical for COG complex integrity","pmids":["17220172"],"is_preprint":false}],"current_model":"COG1 (LDLB) is an ~110-kDa peripheral Golgi protein that serves as a structural scaffold for the hetero-octameric COG complex: it is required for full assembly of the ~950-kDa complex (including incorporation of COG2/ldlCp) and for Golgi association of complex subunits, and it interacts directly with the C-terminus of COG8 to stabilize the intact complex; loss of either COG1 or its COG8-binding interface causes disassembly into smaller subcomplexes and impairs multiple Golgi glycosylation reactions."},"narrative":{"mechanistic_narrative":"COG1 (LDLB) is an ~110-kDa peripheral Golgi protein that functions as a structural scaffold required for assembly of the multisubunit COG (conserved oligomeric Golgi) complex governing Golgi glycosylation [PMID:9927668]. COG1 is essential for full assembly of the ~950-kDa cytosolic complex containing COG2 (ldlCp); in COG1-deficient cells this complex collapses to ~700 kDa, and Golgi association of subunits and normal luminal Golgi processing are lost [PMID:9927668]. COG1 interacts directly with the C-terminal 76 amino acids of COG8, an interaction mechanistically required for stable formation of the intact hetero-octameric complex: loss of this interface produces secondary COG1 deficiency, breakdown into smaller subcomplexes, defective N- and O-glycosylation, and reduced Golgi beta1,4-galactosyltransferase, all reversible by restoring full-length COG8 [PMID:17220172]. Beyond its scaffolding role in COG complex integrity and Golgi glycosylation, no further mechanistic detail has been characterized in the available corpus.","teleology":[{"year":1999,"claim":"Established that COG1 is a Golgi-associated protein required to assemble a large cytosolic complex, defining its role as essential for complex integrity rather than as an isolated enzyme.","evidence":"Expression cloning and complementation of ldlB CHO mutant cells with size-exclusion fractionation of cytosols","pmids":["9927668"],"confidence":"High","gaps":["Did not resolve the full subunit composition or stoichiometry of the complex","Direct binding partners of COG1 within the complex not identified","Molecular basis of the glycosylation defects left undefined"]},{"year":2007,"claim":"Identified a direct COG1–COG8 interaction via the COG8 C-terminus and showed it is mechanistically required for assembly of the intact hetero-octameric COG complex and proper Golgi glycosylation.","evidence":"Patient fibroblast analysis, glycan mass spectrometry, co-immunoprecipitation, and complementation with full-length COG8","pmids":["17220172"],"confidence":"High","gaps":["Structural detail of the COG1–COG8 interface not resolved","How subcomplex formation translates into specific glycosyltransferase mislocalization not mechanistically defined","Interactions of COG1 with other COG subunits beyond COG8 not mapped"]},{"year":null,"claim":"The molecular mechanism by which COG1-anchored complex assembly is coupled to tethering and trafficking events that maintain Golgi glycosylation machinery remains unresolved.","evidence":"","pmids":[],"confidence":"High","gaps":["No structural model of COG1 within the assembled complex","Membrane-recruitment mechanism of COG1 to the Golgi not characterized","Direct link between subcomplex states and specific transport steps not established"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0005198","term_label":"structural molecule activity","supporting_discovery_ids":[0,1]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[1]}],"localization":[{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[0]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[0]}],"pathway":[{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[0]}],"complexes":["COG complex"],"partners":["COG8","COG2"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q8WTW3","full_name":"Conserved oligomeric Golgi complex subunit 1","aliases":["Component of oligomeric Golgi complex 1"],"length_aa":980,"mass_kda":109.0,"function":"Required for normal Golgi function","subcellular_location":"Golgi apparatus membrane","url":"https://www.uniprot.org/uniprotkb/Q8WTW3/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/COG1","classification":"Common Essential","n_dependent_lines":716,"n_total_lines":1208,"dependency_fraction":0.5927152317880795},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/COG1","total_profiled":1310},"omim":[{"mim_id":"617084","title":"TRANSMEMBRANE PROTEIN 59; TMEM59","url":"https://www.omim.org/entry/617084"},{"mim_id":"611209","title":"CONGENITAL DISORDER OF GLYCOSYLATION, TYPE IIg; CDG2G","url":"https://www.omim.org/entry/611209"},{"mim_id":"611182","title":"CONGENITAL DISORDER OF GLYCOSYLATION, TYPE IIh; CDG2H","url":"https://www.omim.org/entry/611182"},{"mim_id":"610089","title":"RAD50-INTERACTING PROTEIN 1; RINT1","url":"https://www.omim.org/entry/610089"},{"mim_id":"608779","title":"CONGENITAL DISORDER OF GLYCOSYLATION, TYPE IIe; CDG2E","url":"https://www.omim.org/entry/608779"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/COG1"},"hgnc":{"alias_symbol":["KIAA1381"],"prev_symbol":["LDLB"]},"alphafold":{"accession":"Q8WTW3","domains":[{"cath_id":"-","chopping":"117-369","consensus_level":"medium","plddt":85.1331,"start":117,"end":369},{"cath_id":"-","chopping":"413-480_503-539_558-638_663-682","consensus_level":"medium","plddt":88.5744,"start":413,"end":682},{"cath_id":"-","chopping":"704-827_834-874","consensus_level":"high","plddt":85.1533,"start":704,"end":874},{"cath_id":"1.20.5","chopping":"21-90","consensus_level":"medium","plddt":84.8049,"start":21,"end":90}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8WTW3","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q8WTW3-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q8WTW3-F1-predicted_aligned_error_v6.png","plddt_mean":77.31},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=COG1","jax_strain_url":"https://www.jax.org/strain/search?query=COG1"},"sequence":{"accession":"Q8WTW3","fasta_url":"https://rest.uniprot.org/uniprotkb/Q8WTW3.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q8WTW3/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8WTW3"}},"corpus_meta":[{"pmid":"17220172","id":"PMC_17220172","title":"A new inborn error of glycosylation due to a Cog8 deficiency reveals a critical role for the Cog1-Cog8 interaction in COG complex formation.","date":"2007","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/17220172","citation_count":103,"is_preprint":false},{"pmid":"28438793","id":"PMC_28438793","title":"Brassinosteroid Biosynthesis Is Modulated via a Transcription Factor Cascade of COG1, PIF4, and PIF5.","date":"2017","source":"Plant physiology","url":"https://pubmed.ncbi.nlm.nih.gov/28438793","citation_count":61,"is_preprint":false},{"pmid":"9927668","id":"PMC_9927668","title":"Expression cloning of LDLB, a gene essential for normal Golgi function and assembly of the ldlCp complex.","date":"1999","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/9927668","citation_count":50,"is_preprint":false},{"pmid":"12482710","id":"PMC_12482710","title":"Caenorhabditis elegans cog-1 locus encodes GTX/Nkx6.1 homeodomain proteins and regulates multiple aspects of reproductive system development.","date":"2002","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/12482710","citation_count":46,"is_preprint":false},{"pmid":"37248220","id":"PMC_37248220","title":"The COG1-OsSERL2 complex senses cold to trigger signaling network for chilling tolerance in japonica rice.","date":"2023","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/37248220","citation_count":42,"is_preprint":false},{"pmid":"19189954","id":"PMC_19189954","title":"Cis-regulatory mutations in the Caenorhabditis elegans homeobox gene locus cog-1 affect neuronal development.","date":"2009","source":"Genetics","url":"https://pubmed.ncbi.nlm.nih.gov/19189954","citation_count":28,"is_preprint":false},{"pmid":"33960418","id":"PMC_33960418","title":"COG1-congenital disorders of glycosylation: Milder presentation and review.","date":"2021","source":"Clinical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/33960418","citation_count":5,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":5207,"output_tokens":763,"usd":0.013533,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":7145,"output_tokens":1386,"usd":0.035187,"stage2_stop_reason":"end_turn"},"total_usd":0.04872,"stage1_batch_id":"msgbatch_01ACAxJQabDsht39JXeWG22d","stage2_batch_id":"msgbatch_01QEU22A9U5sbPTgsMzTmvSf","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1999,\n      \"finding\": \"COG1 (LDLB) encodes an ~110-kDa protein (ldlBp) that localizes to the Golgi apparatus and is required for normal assembly of an ~950-kDa cytosolic complex containing ldlCp (COG2); in ldlB-deficient cells this complex is reduced to ~700 kDa, demonstrating that COG1 is essential for full complex assembly and for Golgi association of ldlCp and normal luminal Golgi processing activities.\",\n      \"method\": \"Retrovirus-based expression cloning, size-exclusion fractionation of cytosols, complementation of ldlB CHO mutant cells\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — functional complementation, biochemical fractionation, and complex-size analysis in a defined mutant background, replicated conceptually by subsequent COG literature\",\n      \"pmids\": [\"9927668\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"The C-terminal 76 amino acids of COG8 are required for direct interaction with COG1; loss of this interaction (via a truncating COG8 mutation) causes secondary COG1 deficiency, prevents assembly of the intact hetero-octameric COG complex, and results in appearance of smaller subcomplexes with defective N- and O-glycosylation and reduced Golgi beta1,4-galactosyltransferase levels. Full-length COG8 transfection restored O-glycosylation, confirming the Cog1–Cog8 interaction is mechanistically required for stable complex formation.\",\n      \"method\": \"Patient fibroblast analysis, mass spectrometry of glycan structures, protein interaction/co-immunoprecipitation analysis, complementation by transfection of full-length COG8\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (glycan MS, protein-level interaction analysis, functional complementation) in a single rigorous study establishing the Cog1–Cog8 interaction as critical for COG complex integrity\",\n      \"pmids\": [\"17220172\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"COG1 (LDLB) is an ~110-kDa peripheral Golgi protein that serves as a structural scaffold for the hetero-octameric COG complex: it is required for full assembly of the ~950-kDa complex (including incorporation of COG2/ldlCp) and for Golgi association of complex subunits, and it interacts directly with the C-terminus of COG8 to stabilize the intact complex; loss of either COG1 or its COG8-binding interface causes disassembly into smaller subcomplexes and impairs multiple Golgi glycosylation reactions.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"COG1 (LDLB) is an ~110-kDa peripheral Golgi protein that functions as a structural scaffold required for assembly of the multisubunit COG (conserved oligomeric Golgi) complex governing Golgi glycosylation [#0]. COG1 is essential for full assembly of the ~950-kDa cytosolic complex containing COG2 (ldlCp); in COG1-deficient cells this complex collapses to ~700 kDa, and Golgi association of subunits and normal luminal Golgi processing are lost [#0]. COG1 interacts directly with the C-terminal 76 amino acids of COG8, an interaction mechanistically required for stable formation of the intact hetero-octameric complex: loss of this interface produces secondary COG1 deficiency, breakdown into smaller subcomplexes, defective N- and O-glycosylation, and reduced Golgi beta1,4-galactosyltransferase, all reversible by restoring full-length COG8 [#1]. Beyond its scaffolding role in COG complex integrity and Golgi glycosylation, no further mechanistic detail has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 1999,\n      \"claim\": \"Established that COG1 is a Golgi-associated protein required to assemble a large cytosolic complex, defining its role as essential for complex integrity rather than as an isolated enzyme.\",\n      \"evidence\": \"Expression cloning and complementation of ldlB CHO mutant cells with size-exclusion fractionation of cytosols\",\n      \"pmids\": [\"9927668\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Did not resolve the full subunit composition or stoichiometry of the complex\",\n        \"Direct binding partners of COG1 within the complex not identified\",\n        \"Molecular basis of the glycosylation defects left undefined\"\n      ]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Identified a direct COG1–COG8 interaction via the COG8 C-terminus and showed it is mechanistically required for assembly of the intact hetero-octameric COG complex and proper Golgi glycosylation.\",\n      \"evidence\": \"Patient fibroblast analysis, glycan mass spectrometry, co-immunoprecipitation, and complementation with full-length COG8\",\n      \"pmids\": [\"17220172\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Structural detail of the COG1–COG8 interface not resolved\",\n        \"How subcomplex formation translates into specific glycosyltransferase mislocalization not mechanistically defined\",\n        \"Interactions of COG1 with other COG subunits beyond COG8 not mapped\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The molecular mechanism by which COG1-anchored complex assembly is coupled to tethering and trafficking events that maintain Golgi glycosylation machinery remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No structural model of COG1 within the assembled complex\",\n        \"Membrane-recruitment mechanism of COG1 to the Golgi not characterized\",\n        \"Direct link between subcomplex states and specific transport steps not established\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005198\", \"supporting_discovery_ids\": [0, 1]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [1]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"complexes\": [\"COG complex\"],\n    \"partners\": [\"COG8\", \"COG2\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"faith_supported":2,"faith_total":3,"faith_pct":66.66666666666667}}