{"gene":"VCF1","run_date":"2026-06-11T09:02:06","timeline":{"discoveries":[{"year":2023,"finding":"VCF1 (FAM104A) and its paralog VCF2 bind p97/VCP directly via a novel alpha-helical motif and associate with p97-UFD1-NPL4 and p97-UBXN2B complexes in cells.","method":"Direct binding assay, co-immunoprecipitation in cells","journal":"eLife","confidence":"High","confidence_rationale":"Tier 2 / Moderate — direct binding and reciprocal Co-IP demonstrated, two orthogonal methods, single lab","pmids":["37713320"],"is_preprint":false},{"year":2023,"finding":"VCF1 and VCF2 localize to the nucleus and promote nuclear import of p97; loss of VCF1/2 results in reduced nuclear p97 levels.","method":"Subcellular fractionation, loss-of-function (VCF1/2 knockout/knockdown) with quantification of nuclear p97 levels","journal":"eLife","confidence":"High","confidence_rationale":"Tier 2 / Moderate — direct localization experiment with functional consequence (reduced nuclear p97), KO phenotype, single lab with orthogonal methods","pmids":["37713320"],"is_preprint":false},{"year":2023,"finding":"Loss of VCF1/2 results in slow growth and hypersensitivity to chemical inhibition of p97 in the absence and presence of DNA damage, indicating VCF1/2 are critical regulators of nuclear p97 functions.","method":"Loss-of-function genetic studies (KO cells) with growth and drug sensitivity assays","journal":"eLife","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean KO with defined cellular phenotype (growth, p97 inhibitor sensitivity), single lab","pmids":["37713320"],"is_preprint":false},{"year":2024,"finding":"VCF1 binds p97 directly via a conserved alpha-helical motif that recognizes the p97 N-domain with unusually high affinity, exceeding that of other known p97 cofactors.","method":"Structure-function studies, direct binding assays (affinity measurements), mutagenesis of the alpha-helical motif","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1 / Moderate — detailed structure-function studies including affinity measurements and mutagenesis, single lab but multiple orthogonal methods","pmids":["38503733"],"is_preprint":false},{"year":2024,"finding":"VCF1 engages in joint p97 complex formation with the heterodimeric cofactor UFD1-NPL4 and promotes p97-UFD1-NPL4-dependent proteasomal degradation of ubiquitylated substrates in cells.","method":"Co-immunoprecipitation, proteasomal degradation assays in cells (loss-of-function)","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP plus functional degradation assay, single lab, two orthogonal methods","pmids":["38503733"],"is_preprint":false},{"year":2024,"finding":"VCF1 indirectly stimulates UFD1-NPL4 interactions with ubiquitin conjugates via its binding to p97, but VCF1 itself has no intrinsic affinity for ubiquitin.","method":"Binding assays (ubiquitin-binding tests), co-immunoprecipitation, structure-function studies","journal":"Nature communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct binding experiments ruling out intrinsic ubiquitin affinity and demonstrating indirect stimulation via p97, single lab","pmids":["38503733"],"is_preprint":false}],"current_model":"VCF1 (FAM104A) is a p97/VCP nuclear cofactor that directly binds the p97 N-domain via a conserved high-affinity alpha-helical motif, promotes nuclear import of p97, associates with p97-UFD1-NPL4 complexes, and indirectly facilitates UFD1-NPL4 recruitment to ubiquitylated substrates to drive their proteasomal degradation; loss of VCF1 reduces nuclear p97 levels and sensitizes cells to p97 inhibition and DNA damage."},"narrative":{"mechanistic_narrative":"VCF1 (FAM104A) is a nuclear cofactor of the AAA+ ATPase p97/VCP that controls the nuclear pool and activity of p97 in ubiquitin-dependent protein degradation [PMID:37713320]. VCF1 binds the p97 N-domain directly through a conserved alpha-helical motif that recognizes p97 with unusually high affinity, exceeding that of other known p97 cofactors [PMID:38503733]. Through this interaction VCF1 localizes to the nucleus and promotes nuclear import of p97, such that its loss reduces nuclear p97 levels [PMID:37713320]. VCF1 forms joint complexes with the heterodimeric cofactor UFD1-NPL4 and drives p97-UFD1-NPL4-dependent proteasomal degradation of ubiquitylated substrates; while VCF1 itself has no intrinsic ubiquitin affinity, its binding to p97 indirectly stimulates UFD1-NPL4 engagement with ubiquitin conjugates [PMID:38503733]. Consistent with a role in nuclear p97 function, loss of VCF1 causes slow growth and hypersensitizes cells to p97 inhibition both with and without DNA damage [PMID:37713320].","teleology":[{"year":2023,"claim":"Establishing that VCF1 is a bona fide p97 cofactor answered whether this previously uncharacterized protein physically engages the p97 segregase machinery.","evidence":"direct binding assay and reciprocal co-immunoprecipitation in cells identifying a novel alpha-helical p97-binding motif and association with p97-UFD1-NPL4 and p97-UBXN2B complexes","pmids":["37713320"],"confidence":"High","gaps":["Did not resolve the structural basis or affinity of the binding motif","Functional consequence of complex association not yet defined"]},{"year":2023,"claim":"Linking VCF1 to nuclear p97 import explained where and how VCF1 exerts its function on the p97 system.","evidence":"subcellular fractionation and VCF1/2 loss-of-function showing nuclear localization and reduced nuclear p97 upon depletion","pmids":["37713320"],"confidence":"High","gaps":["Mechanism of how VCF1 drives nuclear import not defined","Whether import depends on the p97-binding motif untested at this stage"]},{"year":2023,"claim":"Demonstrating growth and drug-sensitivity phenotypes established VCF1 as a functionally important regulator of nuclear p97 rather than a passive binder.","evidence":"knockout cells assayed for growth and sensitivity to chemical p97 inhibition with and without DNA damage","pmids":["37713320"],"confidence":"Medium","gaps":["Single lab phenotype","Specific nuclear substrates or pathways affected not identified"]},{"year":2024,"claim":"Quantifying the binding interaction defined the molecular determinant of VCF1-p97 engagement and distinguished it from other cofactors.","evidence":"structure-function studies, affinity measurements and mutagenesis of the alpha-helical motif recognizing the p97 N-domain","pmids":["38503733"],"confidence":"High","gaps":["No high-resolution structure of the complex reported in the timeline","Functional consequence of the unusually high affinity not fully explored"]},{"year":2024,"claim":"Connecting VCF1 to substrate degradation answered how its p97 binding translates into a biochemical output.","evidence":"co-immunoprecipitation and proteasomal degradation assays showing joint VCF1-UFD1-NPL4 complex formation and VCF1-dependent degradation of ubiquitylated substrates; ubiquitin-binding tests showing VCF1 lacks intrinsic ubiquitin affinity but indirectly stimulates UFD1-NPL4 binding to conjugates","pmids":["38503733"],"confidence":"High","gaps":["Specific physiological substrates not enumerated","Mechanism by which p97 binding allosterically enhances UFD1-NPL4 conjugate engagement unresolved"]},{"year":null,"claim":"The identity of the nuclear substrates and pathways governed by VCF1-directed p97 activity, and the structural basis for its enhancement of UFD1-NPL4, remain open.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No defined endogenous substrate set","No complex structure","Relationship between nuclear import role and degradation role not integrated"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,3,4]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[4,5]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[1]}],"pathway":[{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[4]}],"complexes":["p97-UFD1-NPL4","p97-UBXN2B"],"partners":["VCP","UFD1","NPL4","VCF2"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q969W3","full_name":"Protein VCF1","aliases":["VCP nuclear cofactor family member 1"],"length_aa":186,"mass_kda":19.5,"function":"","subcellular_location":"","url":"https://www.uniprot.org/uniprotkb/Q969W3/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/VCF1","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/VCF1","total_profiled":1310},"omim":[{"mim_id":"621109","title":"VCP NUCLEAR COFACTOR FAMILY, MEMBER 1; VCF1","url":"https://www.omim.org/entry/621109"},{"mim_id":"601023","title":"VALOSIN-CONTAINING PROTEIN; VCP","url":"https://www.omim.org/entry/601023"},{"mim_id":"301141","title":"VCP NUCLEAR COFACTOR FAMILY, MEMBER 2; VCF2","url":"https://www.omim.org/entry/301141"}],"hpa":{"profiled":true,"resolved_as":"FAM104A","reliability":"Approved","locations":[{"location":"Nucleoplasm","reliability":"Approved"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"testis","ntpm":92.9}],"url":"https://www.proteinatlas.org/search/FAM104A"},"hgnc":{"alias_symbol":["FLJ14775"],"prev_symbol":["FAM104A"]},"alphafold":{"accession":"Q969W3","domains":[],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q969W3","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q969W3-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q969W3-F1-predicted_aligned_error_v6.png","plddt_mean":61.78},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=VCF1","jax_strain_url":"https://www.jax.org/strain/search?query=VCF1"},"sequence":{"accession":"Q969W3","fasta_url":"https://rest.uniprot.org/uniprotkb/Q969W3.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q969W3/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q969W3"}},"corpus_meta":[{"pmid":"37713320","id":"PMC_37713320","title":"The FAM104 proteins VCF1/2 promote the nuclear localization of p97/VCP.","date":"2023","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/37713320","citation_count":6,"is_preprint":false},{"pmid":"38503733","id":"PMC_38503733","title":"VCF1 is a p97/VCP cofactor promoting recognition of ubiquitylated p97-UFD1-NPL4 substrates.","date":"2024","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/38503733","citation_count":6,"is_preprint":false},{"pmid":"38224029","id":"PMC_38224029","title":"Identification of Renal Transplantation Rejection Biomarkers in Blood Using the Systems Biology Approach.","date":"2023","source":"Iranian biomedical journal","url":"https://pubmed.ncbi.nlm.nih.gov/38224029","citation_count":3,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":3679,"output_tokens":1266,"usd":0.015014,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":7876,"output_tokens":1967,"usd":0.044277,"stage2_stop_reason":"end_turn"},"total_usd":0.059291,"stage1_batch_id":"msgbatch_01UT1AahFPCAyn2uVweS7A9z","stage2_batch_id":"msgbatch_01HuKWtKNT4Pqj1bc8eEP5RV","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2023,\n      \"finding\": \"VCF1 (FAM104A) and its paralog VCF2 bind p97/VCP directly via a novel alpha-helical motif and associate with p97-UFD1-NPL4 and p97-UBXN2B complexes in cells.\",\n      \"method\": \"Direct binding assay, co-immunoprecipitation in cells\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct binding and reciprocal Co-IP demonstrated, two orthogonal methods, single lab\",\n      \"pmids\": [\"37713320\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"VCF1 and VCF2 localize to the nucleus and promote nuclear import of p97; loss of VCF1/2 results in reduced nuclear p97 levels.\",\n      \"method\": \"Subcellular fractionation, loss-of-function (VCF1/2 knockout/knockdown) with quantification of nuclear p97 levels\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization experiment with functional consequence (reduced nuclear p97), KO phenotype, single lab with orthogonal methods\",\n      \"pmids\": [\"37713320\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Loss of VCF1/2 results in slow growth and hypersensitivity to chemical inhibition of p97 in the absence and presence of DNA damage, indicating VCF1/2 are critical regulators of nuclear p97 functions.\",\n      \"method\": \"Loss-of-function genetic studies (KO cells) with growth and drug sensitivity assays\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean KO with defined cellular phenotype (growth, p97 inhibitor sensitivity), single lab\",\n      \"pmids\": [\"37713320\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"VCF1 binds p97 directly via a conserved alpha-helical motif that recognizes the p97 N-domain with unusually high affinity, exceeding that of other known p97 cofactors.\",\n      \"method\": \"Structure-function studies, direct binding assays (affinity measurements), mutagenesis of the alpha-helical motif\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — detailed structure-function studies including affinity measurements and mutagenesis, single lab but multiple orthogonal methods\",\n      \"pmids\": [\"38503733\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"VCF1 engages in joint p97 complex formation with the heterodimeric cofactor UFD1-NPL4 and promotes p97-UFD1-NPL4-dependent proteasomal degradation of ubiquitylated substrates in cells.\",\n      \"method\": \"Co-immunoprecipitation, proteasomal degradation assays in cells (loss-of-function)\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP plus functional degradation assay, single lab, two orthogonal methods\",\n      \"pmids\": [\"38503733\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"VCF1 indirectly stimulates UFD1-NPL4 interactions with ubiquitin conjugates via its binding to p97, but VCF1 itself has no intrinsic affinity for ubiquitin.\",\n      \"method\": \"Binding assays (ubiquitin-binding tests), co-immunoprecipitation, structure-function studies\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct binding experiments ruling out intrinsic ubiquitin affinity and demonstrating indirect stimulation via p97, single lab\",\n      \"pmids\": [\"38503733\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"VCF1 (FAM104A) is a p97/VCP nuclear cofactor that directly binds the p97 N-domain via a conserved high-affinity alpha-helical motif, promotes nuclear import of p97, associates with p97-UFD1-NPL4 complexes, and indirectly facilitates UFD1-NPL4 recruitment to ubiquitylated substrates to drive their proteasomal degradation; loss of VCF1 reduces nuclear p97 levels and sensitizes cells to p97 inhibition and DNA damage.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"VCF1 (FAM104A) is a nuclear cofactor of the AAA+ ATPase p97/VCP that controls the nuclear pool and activity of p97 in ubiquitin-dependent protein degradation [#0, #1]. VCF1 binds the p97 N-domain directly through a conserved alpha-helical motif that recognizes p97 with unusually high affinity, exceeding that of other known p97 cofactors [#3]. Through this interaction VCF1 localizes to the nucleus and promotes nuclear import of p97, such that its loss reduces nuclear p97 levels [#1]. VCF1 forms joint complexes with the heterodimeric cofactor UFD1-NPL4 and drives p97-UFD1-NPL4-dependent proteasomal degradation of ubiquitylated substrates; while VCF1 itself has no intrinsic ubiquitin affinity, its binding to p97 indirectly stimulates UFD1-NPL4 engagement with ubiquitin conjugates [#4, #5]. Consistent with a role in nuclear p97 function, loss of VCF1 causes slow growth and hypersensitizes cells to p97 inhibition both with and without DNA damage [#2].\",\n  \"teleology\": [\n    {\n      \"year\": 2023,\n      \"claim\": \"Establishing that VCF1 is a bona fide p97 cofactor answered whether this previously uncharacterized protein physically engages the p97 segregase machinery.\",\n      \"evidence\": \"direct binding assay and reciprocal co-immunoprecipitation in cells identifying a novel alpha-helical p97-binding motif and association with p97-UFD1-NPL4 and p97-UBXN2B complexes\",\n      \"pmids\": [\"37713320\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve the structural basis or affinity of the binding motif\", \"Functional consequence of complex association not yet defined\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Linking VCF1 to nuclear p97 import explained where and how VCF1 exerts its function on the p97 system.\",\n      \"evidence\": \"subcellular fractionation and VCF1/2 loss-of-function showing nuclear localization and reduced nuclear p97 upon depletion\",\n      \"pmids\": [\"37713320\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of how VCF1 drives nuclear import not defined\", \"Whether import depends on the p97-binding motif untested at this stage\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Demonstrating growth and drug-sensitivity phenotypes established VCF1 as a functionally important regulator of nuclear p97 rather than a passive binder.\",\n      \"evidence\": \"knockout cells assayed for growth and sensitivity to chemical p97 inhibition with and without DNA damage\",\n      \"pmids\": [\"37713320\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab phenotype\", \"Specific nuclear substrates or pathways affected not identified\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Quantifying the binding interaction defined the molecular determinant of VCF1-p97 engagement and distinguished it from other cofactors.\",\n      \"evidence\": \"structure-function studies, affinity measurements and mutagenesis of the alpha-helical motif recognizing the p97 N-domain\",\n      \"pmids\": [\"38503733\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No high-resolution structure of the complex reported in the timeline\", \"Functional consequence of the unusually high affinity not fully explored\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Connecting VCF1 to substrate degradation answered how its p97 binding translates into a biochemical output.\",\n      \"evidence\": \"co-immunoprecipitation and proteasomal degradation assays showing joint VCF1-UFD1-NPL4 complex formation and VCF1-dependent degradation of ubiquitylated substrates; ubiquitin-binding tests showing VCF1 lacks intrinsic ubiquitin affinity but indirectly stimulates UFD1-NPL4 binding to conjugates\",\n      \"pmids\": [\"38503733\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Specific physiological substrates not enumerated\", \"Mechanism by which p97 binding allosterically enhances UFD1-NPL4 conjugate engagement unresolved\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The identity of the nuclear substrates and pathways governed by VCF1-directed p97 activity, and the structural basis for its enhancement of UFD1-NPL4, remain open.\",\n      \"evidence\": null,\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No defined endogenous substrate set\", \"No complex structure\", \"Relationship between nuclear import role and degradation role not integrated\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 3, 4]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [4, 5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [1]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [4]}\n    ],\n    \"complexes\": [\"p97-UFD1-NPL4\", \"p97-UBXN2B\"],\n    \"partners\": [\"VCP\", \"UFD1\", \"NPL4\", \"VCF2\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"faith_supported":5,"faith_total":5,"faith_pct":100.0}}