Asymmetric ring structure of Vps4 required for ESCRT-III disassembly

Nat Commun. 2015 Dec 3;6:8781. doi: 10.1038/ncomms9781.

Abstract

The vacuolar protein sorting 4 AAA-ATPase (Vps4) recycles endosomal sorting complexes required for transport (ESCRT-III) polymers from cellular membranes. Here we present a 3.6-Å X-ray structure of ring-shaped Vps4 from Metallosphera sedula (MsVps4), seen as an asymmetric pseudohexamer. Conserved key interface residues are shown to be important for MsVps4 assembly, ATPase activity in vitro, ESCRT-III disassembly in vitro and HIV-1 budding. ADP binding leads to conformational changes within the protomer, which might propagate within the ring structure. All ATP-binding sites are accessible and the pseudohexamer binds six ATP with micromolar affinity in vitro. In contrast, ADP occupies one high-affinity and five low-affinity binding sites in vitro, consistent with conformational asymmetry induced on ATP hydrolysis. The structure represents a snapshot of an assembled Vps4 conformation and provides insight into the molecular motions the ring structure undergoes in a concerted action to couple ATP hydrolysis to ESCRT-III substrate disassembly.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / chemistry
  • Adenosine Triphosphate / metabolism
  • Binding Sites
  • Endosomal Sorting Complexes Required for Transport / metabolism*
  • Gene Expression Regulation, Archaeal / physiology
  • HIV-1 / physiology
  • Models, Molecular
  • Mutation
  • Protein Conformation
  • Sulfolobaceae / genetics
  • Sulfolobaceae / metabolism*

Substances

  • Endosomal Sorting Complexes Required for Transport
  • Adenosine Triphosphate

Associated data

  • PDB/4D80
  • PDB/4D81
  • PDB/4D82