Vcp Protein (P97) is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
| Gene | VCP |
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| UniProt ID | P55072 |
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| PDB Structures | 1R3R, 5EHD |
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| Molecular Weight | ~97 kDa |
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| Subcellular Localization | Cytoplasm, nucleus, endoplasmic reticulum, Golgi |
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| Protein Family | AAA+ ATPase family |
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VCP (valosin-containing protein), also known as p97 or CDC48 in yeast, is a AAA+ ATPase that functions as a key segregase in protein quality control. VCP extracts ubiquitinated proteins from membranes, chromatin, and protein complexes for degradation by the proteasome. Mutations in VCP cause inclusion body myopathy with early-onset Paget disease of bone and frontotemporal dementia (IBMPFD/ALS4). VCP is essential for cellular proteostasis and its dysfunction is implicated in multiple neurodegenerative diseases.
VCP is a hexameric AAA+ ATPase forming a ring-shaped complex:
- N-terminal Domain (N): Binds cofactors (UFD1, NPL4, UBXD1) and substrates
- D1 ATPase Domain: First ATPase domain, required for hexamerization and ATP-dependent conformational changes
- D2 ATPase Domain: Second ATPase domain, contains the major ATPase activity driving substrate extraction
- C-terminal Tail: Substrate interaction and regulatory phosphorylation sites
The hexameric ring structure creates a central pore through which substrates are translocated during extraction. ATP hydrolysis drives conformational changes that unfold and extract client proteins from their complexes or membranes.
VCP/p97 is a master regulator of protein quality control with multiple cellular functions:
- ER-Associated Degradation (ERAD): Extracts misfolded proteins from the endoplasmic reticulum for proteasomal degradation
- Chromatin Remodeling: Involved in DNA damage repair, transcription regulation, and replication fork progression
- Mitochondrial Quality Control: Mediates mitophagy by extracting damaged mitochondrial proteins
- Autophagosome Maturation: Facilitates autophagosome-lysosome fusion and cargo delivery
- Proteasomal Targeting: Delivers ubiquitinated substrates to the 26S proteasome for degradation
- Nuclear Envelope Reformation: Functions in nuclear envelope assembly after mitosis
- Signal Transduction: Modulates NF-κB and other stress-responsive signaling pathways
VCP interacts with numerous cofactors that direct its activity to specific cellular compartments and substrates.
¶ IBMPFD (Inclusion Body Myopathy with PDB and FTD)
- Mutations: R155H, R155P, A232E, R191Q cause autosomal dominant disease
- Prevalence: Estimated 1:100,000 - 1:200,000
- Mechanisms: Impaired protein quality control, altered autophagy, TDP-43 pathology
- Features: Adult-onset myopathy, Paget disease of bone, frontotemporal dementia
- Penetrance: 90% by age 50 for myopathy, 30-50% for dementia
- VCP mutations cause a milder, juvenile-onset form of ALS
- Features: Slow progression, distal muscle weakness, sensory involvement
- Often overlaps with IBMPFD phenotype
¶ Sporadic ALS and FTD
- VCP mutations found in sporadic ALS and FTD cases
- VCP-positive inclusions observed in sporadic disease
- Altered VCP function contributes to TDP-43 proteinopathy
- VCP inclusions in sporadic inclusion body myositis (sIBM)
- Altered VCP function in Alzheimer's disease, Parkinson's disease
- Implicated in Huntington disease pathogenesis
- Role in age-related proteostasis decline
| Approach |
Status |
Description |
| VCP Inhibitors (NMS-873, DBeQ) |
Preclinical |
Induce proteotoxic stress in cancer; potential for neurodegeneration |
| Proteostasis Modulators |
Research |
Enhance protein quality control pathways |
| Autophagy Enhancers |
Preclinical |
Restore autophagic flux; rapamycin, trehalose |
| Cofactor Interaction Modulators |
Research |
Target VCP-UFD1-NPL4 interactions |
| Gene Therapy |
Research |
Modulate VCP expression; AAV-VCP |
- Watts GD et al. (2004) Inclusion body myopathy, Paget disease of bone, and frontotemporal dementia are caused by VCP mutations. Nat Genet 36(4):377-381. PMID:15034582
- Meyer H et al. (2012) VCP/p97-mediated unfolding: AAA ATPase. Nat Rev Mol Cell Biol 13(7):475-480. PMID:22740209
- Nalbandian A et al. (2011) VCP disease: Pathogenesis and therapy. Neurology 77(8):771-777. PMID:21813790
- Ju JS et al. (2009) Valosin-containing protein disease: A multi-system proteinopathy. Autophagy 5(2):193-199. PMID:19066469
- Kimonis VE et al. (2008) VCP disease. J Mol Neurosci 35(3):331-336. PMID:18236004
The study of Vcp Protein (P97) has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
[1] Watts GD et al. Nat Genet. 2004;36(4):377-381.
[2] Meyer H et al. Nat Rev Mol Cell Biol. 2012;13(7):475-480.
[3] Nalbandian A et al. Neurology. 2011;77(8):771-777.
[4] Ju JS et al. Autophagy. 2009;5(2):193-199.
[5] Kimonis VE et al. J Mol Neurosci. 2008;35(3):331-336.