Hexamerization of p97-VCP is promoted by ATP binding to the D1 domain and required for ATPase and biological activities

Biochem Biophys Res Commun. 2003 Jan 10;300(2):253-60. doi: 10.1016/s0006-291x(02)02840-1.

Abstract

The 97-kDa valosin-containing protein (p97-VCP or VCP), a hexameric AAA ATPase, plays an important role in diverse cell activities, including ubiquitin-proteasome mediated protein degradation. In this report, we studied dissociation-reassembly kinetics to analyze the structure-function relationship in VCP. Urea-dissociated VCP can reassemble by itself, but addition of ATP, ADP, or ATP-gamma S accelerates the reassembly. Mutation in the ATP-binding site of D1, but not D2, domain abolishes the ATP acceleration effect and further delays the reassembly. Using hybrid hexamers of the wild type and ATP-binding site mutant, we show that hexameric structure and proper communication among the subunits are required for the ATPase activity and ubiquitin-proteasome mediated degradation. Thus, ATP-binding site in D1 plays a major role in VCP hexamerization, of which proper inter-subunit interaction is essential for the activities.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenosine Triphosphatases / chemistry*
  • Adenosine Triphosphatases / metabolism
  • Adenosine Triphosphatases / physiology*
  • Adenosine Triphosphate / metabolism*
  • Animals
  • Binding Sites
  • Cell Cycle Proteins / chemistry*
  • Cell Cycle Proteins / metabolism
  • Cell Cycle Proteins / physiology*
  • Cysteine Endopeptidases / metabolism
  • Kinetics
  • Multienzyme Complexes / metabolism
  • Mutagenesis, Site-Directed
  • Proteasome Endopeptidase Complex
  • Protein Denaturation
  • Protein Structure, Tertiary
  • Protein Subunits
  • Structure-Activity Relationship
  • Ubiquitin / metabolism
  • Urea / pharmacology
  • Valosin Containing Protein

Substances

  • Cell Cycle Proteins
  • Multienzyme Complexes
  • Protein Subunits
  • Ubiquitin
  • Adenosine Triphosphate
  • Urea
  • Cysteine Endopeptidases
  • Proteasome Endopeptidase Complex
  • Adenosine Triphosphatases
  • Valosin Containing Protein