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model: Edison Scientific Literature
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start_time: '2026-04-21T09:20:01.297376'
end_time: '2026-04-21T09:32:18.075113'
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template_file: templates/gene_research_go_focused.md
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organism: human
gene_id: VCP
gene_symbol: VCP
uniprot_accession: P55072
protein_description: 'RecName: Full=Transitional endoplasmic reticulum ATPase; Short=TER
ATPase; EC=3.6.4.6 {ECO:0000269|PubMed:26471729}; AltName: Full=15S Mg(2+)-ATPase
p97 subunit; AltName: Full=Valosin-containing protein; Short=VCP;'
gene_info: Name=VCP; Synonyms=HEL-220 {ECO:0000312|EMBL:ACI46036.1}, HEL-S-70 {ECO:0000312|EMBL:ACI46044.1};
organism_full: Homo sapiens (Human).
protein_family: Belongs to the AAA ATPase family. .
protein_domains: AAA+_ATPase. (IPR003593); AAA_ATPase_CDC48. (IPR005938); AAA_ATPase_domain.
(IPR050168); AAA_lid_3. (IPR041569); Asp_de-COase-like_dom_sf. (IPR009010)
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citation_count: 47

Question

Gene Research for Functional Annotation

⚠️ CRITICAL: Gene/Protein Identification Context

BEFORE YOU BEGIN RESEARCH: You MUST verify you are researching the CORRECT gene/protein. Gene symbols can be ambiguous, especially for less well-characterized genes from non-model organisms.

Target Gene/Protein Identity (from UniProt):

• UniProt Accession: P55072
• Protein Description: RecName: Full=Transitional endoplasmic reticulum ATPase; Short=TER ATPase; EC=3.6.4.6 {ECO:0000269|PubMed:26471729}; AltName: Full=15S Mg(2+)-ATPase p97 subunit; AltName: Full=Valosin-containing protein; Short=VCP;
• Gene Information: Name=VCP; Synonyms=HEL-220 {ECO:0000312|EMBL:ACI46036.1}, HEL-S-70 {ECO:0000312|EMBL:ACI46044.1};
• Organism (full): Homo sapiens (Human).
• Protein Family: Belongs to the AAA ATPase family. .
• Key Domains: AAA+_ATPase. (IPR003593); AAA_ATPase_CDC48. (IPR005938); AAA_ATPase_domain. (IPR050168); AAA_lid_3. (IPR041569); Asp_de-COase-like_dom_sf. (IPR009010)

MANDATORY VERIFICATION STEPS:

1. Check if the gene symbol "VCP" matches the protein description above
2. Verify the organism is correct: Homo sapiens (Human).
3. Check if protein family/domains align with what you find in literature
4. If you find literature for a DIFFERENT gene with the same or similar symbol, STOP

If Gene Symbol is Ambiguous or You Cannot Find Relevant Literature:

DO NOT PROCEED WITH RESEARCH ON A DIFFERENT GENE. Instead:
- State clearly: "The gene symbol 'VCP' is ambiguous or literature is limited for this specific protein"
- Explain what you found (e.g., "Found extensive literature on a different gene with the same symbol in a different organism")
- Describe the protein based ONLY on the UniProt information provided above
- Suggest that the protein function can be inferred from domain/family information

Research Target:

Please provide a comprehensive research report on the gene VCP (gene ID: VCP, UniProt: P55072) in human.

The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.

You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.

We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.

We are interested in where in or outside the cell the gene product carries out its function.

We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.

Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.

Output

Question: You are an expert researcher providing comprehensive, well-cited information.

Provide detailed information focusing on:
1. Key concepts and definitions with current understanding
2. Recent developments and latest research (prioritize 2023-2024 sources)
3. Current applications and real-world implementations
4. Expert opinions and analysis from authoritative sources
5. Relevant statistics and data from recent studies

Format as a comprehensive research report with proper citations. Include URLs and publication dates where available.
Always prioritize recent, authoritative sources and provide specific citations for all major claims.

Gene Research for Functional Annotation

⚠️ CRITICAL: Gene/Protein Identification Context

BEFORE YOU BEGIN RESEARCH: You MUST verify you are researching the CORRECT gene/protein. Gene symbols can be ambiguous, especially for less well-characterized genes from non-model organisms.

Target Gene/Protein Identity (from UniProt):

• UniProt Accession: P55072
• Protein Description: RecName: Full=Transitional endoplasmic reticulum ATPase; Short=TER ATPase; EC=3.6.4.6 {ECO:0000269|PubMed:26471729}; AltName: Full=15S Mg(2+)-ATPase p97 subunit; AltName: Full=Valosin-containing protein; Short=VCP;
• Gene Information: Name=VCP; Synonyms=HEL-220 {ECO:0000312|EMBL:ACI46036.1}, HEL-S-70 {ECO:0000312|EMBL:ACI46044.1};
• Organism (full): Homo sapiens (Human).
• Protein Family: Belongs to the AAA ATPase family. .
• Key Domains: AAA+_ATPase. (IPR003593); AAA_ATPase_CDC48. (IPR005938); AAA_ATPase_domain. (IPR050168); AAA_lid_3. (IPR041569); Asp_de-COase-like_dom_sf. (IPR009010)

MANDATORY VERIFICATION STEPS:

1. Check if the gene symbol "VCP" matches the protein description above
2. Verify the organism is correct: Homo sapiens (Human).
3. Check if protein family/domains align with what you find in literature
4. If you find literature for a DIFFERENT gene with the same or similar symbol, STOP

If Gene Symbol is Ambiguous or You Cannot Find Relevant Literature:

DO NOT PROCEED WITH RESEARCH ON A DIFFERENT GENE. Instead:
- State clearly: "The gene symbol 'VCP' is ambiguous or literature is limited for this specific protein"
- Explain what you found (e.g., "Found extensive literature on a different gene with the same symbol in a different organism")
- Describe the protein based ONLY on the UniProt information provided above
- Suggest that the protein function can be inferred from domain/family information

Research Target:

Please provide a comprehensive research report on the gene VCP (gene ID: VCP, UniProt: P55072) in human.

The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.

You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.

We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.

We are interested in where in or outside the cell the gene product carries out its function.

We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.

Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.

Research report: Human VCP (p97) — functional annotation (UniProt P55072)

1) Identity verification and key concepts/definitions (current understanding)

Correct target protein. The UniProt accession P55072 corresponds to human valosin‑containing protein (VCP), also widely referred to as p97 (or Cdc48 in yeast). Recent authoritative reviews and primary literature consistently describe this same protein as a conserved, essential AAA+ ATPase/unfoldase that functions as a hexameric “protein extractor” in ubiquitin‑dependent pathways. (pontifex2024valosincontainingprotein(vcp) pages 2-3, chu2023valosincontainingprotein pages 3-4, mirsanaye2024vcf1isa pages 1-2)

Core definition. VCP/p97 is a mechanochemical enzyme that converts ATP binding/hydrolysis into mechanical work to extract (segregate) and/or unfold client proteins—classically ubiquitylated substrates—from macromolecular assemblies or membranes for downstream processing (often proteasomal degradation). (pontifex2024valosincontainingprotein(vcp) pages 2-3, mirsanaye2024vcf1isa pages 1-2, korner2023thefam104proteins pages 1-2)

Domain architecture. Each VCP protomer contains an N‑terminal domain (N domain) followed by two ATPase motor domains (D1 and D2), which assemble into stacked hexameric rings forming a central pore. The N domain is a major interface for cofactor binding and substrate engagement; the D1/D2 rings provide the ATPase-driven unfoldase activity (with D2 typically providing the dominant mechanical force). (pontifex2024valosincontainingprotein(vcp) pages 2-3, chu2023valosincontainingprotein pages 3-4, mirsanaye2024vcf1isa pages 1-2)

Cofactors/adaptors (defining specificity). VCP’s broad functional repertoire is determined by a large network (dozens) of cofactors/adaptors. A key “core” recruitment module is the UFD1–NPL4 (UFD1L–NPLOC4) heterodimer, and many additional cofactors bind the VCP N domain via defined modules/motifs (e.g., UBX/UBX-like domains, VIM/VBM, SHP), or engage C‑terminal regions (e.g., PUB/PUL interactions). These cofactors commonly provide ubiquitin recognition and route VCP to specific pathways/subcellular sites. (mirsanaye2024vcf1isa pages 1-2, korner2023thefam104proteins pages 1-2, mirsanaye2023vcf1isan pages 1-5)

2) Molecular function and enzymatic activity (reaction, substrate specificity)

Enzymatic activity. VCP is an ATPase (EC 3.6.4.6) whose key biochemical output is ATP hydrolysis coupled to conformational cycling of the hexamer. Functionally, this hydrolysis powers threading/unfolding of client polypeptides through the central pore and their extraction from membranes/complexes. (pontifex2024valosincontainingprotein(vcp) pages 2-3, mirsanaye2024vcf1isa pages 1-2)

Substrate targeting/specificity. VCP most characteristically acts on ubiquitylated substrates. Specificity is largely cofactor-determined: cofactors (notably UFD1–NPL4 and UBX-family factors) bind ubiquitin chains and present substrates to VCP for extraction/unfolding, enabling outcomes including proteasomal degradation or remodeling/recycling. (mirsanaye2024vcf1isa pages 1-2, korner2023thefam104proteins pages 1-2, mirsanaye2023vcf1isan pages 1-5)

3) Cellular localization and pathways (where VCP acts; what it does there)

General compartmentalization. VCP functions in multiple compartments, including cytosol and nucleus; this multi-compartment deployment is central to how it supports proteostasis and genome integrity. (pontifex2024valosincontainingprotein(vcp) pages 2-3, chu2023valosincontainingprotein pages 3-4, pontifex2024valosincontainingprotein(vcp) pages 1-2)

ER-associated degradation (ERAD). A major, well-established role is ER protein quality control, where VCP cooperates with ubiquitin ligases and cofactors (commonly UFD1–NPL4) to extract misfolded proteins from the ER for cytosolic degradation. (chu2023valosincontainingprotein pages 6-9, mirzadeh2024molecularmechanismof pages 18-19)

Selective autophagy/lysophagy (endo-lysosomal damage response; ELDR). VCP is recruited to damaged lysosomes and participates in lysophagy through cofactor-defined complexes (often described as an ELDR module involving factors such as UBXD1/UBXN6, PLAA, and YOD1 in review summaries). (chu2023valosincontainingprotein pages 6-9, pontifex2024valosincontainingprotein(vcp) pages 5-7)

A mechanistically detailed 2023 study identifies a regulatory switch at VCP Tyr805: the phosphatase PTP4A2 directly dephosphorylates VCP at Tyr805, enabling VCP association with UBXN6/UBXD1 and PLAA (ELDR components) and promoting lysophagy (including removal of K48-linked ubiquitin conjugates and autophagosome formation on damaged lysosomes). In vivo, Ptp4a2 deletion impaired recovery from glycerol-induced acute kidney injury, consistent with a physiological requirement for this VCP-regulated lysophagy axis. (bai2023ptp4a2promoteslysophagy pages 1-2)

Endocytic recycling (newer pathway-level evidence). Beyond its established degradative roles in the endolysosomal system, a 2023 primary study reports that VCP promotes recycling of endocytic cargo. VCP interacts with myoferlin (MYOF) in a manner dependent on the cofactor PLAA; a fraction of VCP/PLAA localizes to MYOF-, Rab11-, and Rab14-positive endosomal compartments, and pharmacologic inhibition of VCP delays transferrin recycling. (kawan2023p97vcppromotesthe pages 1-2)

Nuclear localization and genome maintenance. VCP has important nuclear functions (DNA replication/mitosis and DNA damage response pathways are repeatedly emphasized in 2023–2024 reviews). (pontifex2024valosincontainingprotein(vcp) pages 10-12, pontifex2024valosincontainingprotein(vcp) pages 1-2)

Mechanistically, nuclear access can be actively regulated by dedicated cofactors: FAM104 proteins (VCF1/VCF2) were identified as p97 interactors that localize to the nucleus and promote nuclear import of VCP. Loss of VCF1/2 reduces nuclear VCP, slows growth, and increases sensitivity to chemical VCP inhibition in the presence and absence of DNA damage, supporting a localization-control model for nuclear VCP functions. (korner2023thefam104proteins pages 1-2)

4) Recent developments and latest research (prioritizing 2023–2024)

Expansion of the cofactor network (2024). A 2024 Nature Communications study established VCF1/FAM104A as an unconventional VCP cofactor: it binds the VCP N domain with unusually high affinity, forms joint complexes with UFD1–NPL4, and promotes recognition/processing of ubiquitylated substrates in the p97–UFD1–NPL4 pathway. (mirsanaye2024vcf1isa pages 1-2)

Structural pharmacology (2024): multiple druggable allosteric sites. In 2024, cryo‑EM studies resolved inhibitor-bound VCP structures showing that triazole-class allosteric inhibitors bind an inter-subunit pocket at the D1–D2 interface (rather than the nucleotide site), shifting helices/loops that mediate domain–domain communication and thereby inhibiting ATPase-driven function. Reported reconstructions were at ~3.23–3.60 Å for inhibitor-bound complexes, including disease-mutant R155H. (nandi2024mechanismofallosteric pages 2-3, nandi2024mechanismofallosteric pages 6-8)

Complementing inhibition, a 2024 PNAS study identified an activating small molecule (VAA1) that binds a C-terminal allosteric pocket and stimulates VCP ATPase activity up to ~threefold, demonstrating that chemical control of VCP includes both inhibition and activation modalities. (jones2024allostericactivationof pages 1-2)

5) Current applications and real-world implementations

5.1 Human disease genetics and clinical phenotypes (MSP1/IBMPFD spectrum; ALS/FTD)

Multisystem proteinopathy-1 (MSP1). Pathogenic VCP variants cause MSP1/IBMPFD spectrum disease with characteristic involvement of skeletal muscle (inclusion body myopathy), bone (Paget disease), and CNS (frontotemporal dementia; sometimes ALS). (shmara2023prevalenceoffrontotemporal pages 1-2, chu2023valosincontainingprotein pages 16-18)

Quantitative phenotype frequencies (cohort data). In a 2023 Neurology Genetics study (Hispanic families, VCP R159H), phenotype frequencies differed substantially from an all-variant comparison cohort:
- All VCP variants cohort (n=187): myopathy 168/187 (89.8%), FTD 55/187 (29.4%), Paget disease 80/187 (42.8%), ALS 16/187 (8.6%).
- R159H cohort (n=39 affected/obligate carriers): myopathy 15/39 (38.5%), FTD 28/39 (71.8%), Paget disease 1/39 (2.6%), ALS 3/39 (7.7%).
The same work reported an apparent sex effect in this variant context (FTD in females 85% in R159H vs 39% in females with other variants) and longer mean survival for R159H (72.5 years) versus a set of 10 other variants (62.53 years). (shmara2023prevalenceoffrontotemporal pages 9-10)