Valosin-Containing Protein is a protein encoded by the VCP gene. This page describes its structure, normal nervous system function, role in neurodegenerative disease, and potential as a therapeutic target.
Valosin-Containing Protein (VCP) (also known as p97) is a hexameric AAA+ ATPase critical for protein degradation, DNA repair, and membrane fusion. VCP mutations cause inclusion body myopathy with early-onset Paget disease of bone (PDB) and frontotemporal dementia (IBMPFD), now termed multisystem proteinopathy (MSP).
| Attribute |
Details |
| Gene Symbol |
VCP |
| Chromosomal Location |
9p13.3 |
| Protein Name |
Valosin-Containing Protein / p97 |
| Molecular Weight |
~97 kDa (per subunit) |
| Primary Function |
AAA+ ATPase, protein degradation, DNA repair |
VCP forms a homohexameric complex:
- N-terminal Domain - Substrate binding and cofactor interactions
- ATPase Domain (D1 and D2) - Hexameric ring with ATPase activity
- C-terminal Domain - Regulatory interactions
- UFD1L - Ubiquitin recognition
- NPL4 - Substrate delivery
- p47 - Membrane trafficking
- UBXD7/8 - Autophagy regulation
VCP is central to ubiquitin-proteasome system (UPS) function:
- Extracts ubiquitinated proteins from complexes
- Delivers substrates to proteasome
- Mutations impair protein clearance
- Accumulation of toxic protein aggregates
VCP mutations disrupt autophagy:
- Impaired autophagosome-lysosome fusion
- Defective mitophagy (mitochondrial clearance)
- Disrupted ribophagy (ribosome clearance)
- Accumulation of damaged organelles
VCP participates in DNA damage response:
- Double-strand break repair
- Replication stress response
- Chromatin remodeling
- Genomic instability in disease
Essential for membrane fusion events:
- Golgi reassembly
- ER network maintenance
- Endosomal trafficking
- Nuclear envelope reformation
VCP mutations cause a triad of disorders:
- Inclusion Body Myopathy - Progressive muscle weakness, typically starting in adulthood
- Paget Disease of Bone - Increased bone turnover, bone pain, deformities
- Frontotemporal Dementia - Cognitive decline, behavioral changes
- VCP mutations found in ~1-2% of familial ALS
- Often presents with combined ALS/dementia phenotype
- Similar pathology to other ALS subtypes (TDP-43 inclusions)
- Rapid disease progression
- VCP variants associated with PD risk
- Role in mitophagy relevant to PD pathogenesis
- Interaction with PINK1/PARKIN pathway
- Research ongoing on therapeutic potential
- VCP involved in amyloid clearance
- Impaired protein homeostasis in AD brain
- Potential therapeutic target
- Interaction with autophagy-lysosome pathway
- TDP-43 (TARDBP) - Co-aggregation in ALS
- FUS - Co-pathology in ALS/FTD
- Ubiquitin - Substrate tagging
- P62/SQSTM1 - Autophagy adaptor
- OPTN - Autophagy receptor
- VCP Inhibitors - Modulate ATPase activity
- Autophagy Enhancers - Bypass VCP-related autophagy defects
- UPS Modulators - Enhance protein clearance
- Mitochondrial Protectants - Support mitophagy
- Small molecule VCP modulators
- Gene therapy for specific mutations
- Autophagy-boosting compounds
- Protein aggregation inhibitors