Mechanism of USP7/HAUSP activation by its C-terminal ubiquitin-like domain and allosteric regulation by GMP-synthetase

Mol Cell. 2011 Oct 7;44(1):147-59. doi: 10.1016/j.molcel.2011.06.034.

Abstract

The ubiquitin-specific protease USP7/HAUSP regulates p53 and MDM2 levels, and cellular localization of FOXO4 and PTEN, and hence is critically important for their role in cellular processes. Here we show how the 64 kDa C-terminal region of USP7 can positively regulate deubiquitinating activity. We present the crystal structure of this USP7/HAUSP ubiquitin-like domain (HUBL) comprised of five ubiquitin-like (Ubl) domains organized in 2-1-2 Ubl units. The last di-Ubl unit, HUBL-45, is sufficient to activate USP7, through binding to a "switching" loop in the catalytic domain, which promotes ubiquitin binding and increases activity 100-fold. This activation can be enhanced allosterically by the metabolic enzyme GMPS. It binds to the first three Ubl domains (HUBL-123) and hyperactivates USP7 by stabilization of the HUBL-45-dependent active state.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Allosteric Site
  • Carbon-Nitrogen Ligases / metabolism*
  • Catalytic Domain
  • Cell Line, Tumor
  • Gene Expression Regulation*
  • Gene Expression Regulation, Enzymologic*
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Kinetics
  • Point Mutation
  • Protein Binding
  • Protein Structure, Tertiary
  • Proto-Oncogene Proteins c-mdm2 / metabolism
  • Tumor Suppressor Protein p53 / metabolism
  • Ubiquitin / chemistry*
  • Ubiquitin Thiolesterase / metabolism*
  • Ubiquitin-Specific Peptidase 7

Substances

  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • Ubiquitin
  • MDM2 protein, human
  • Proto-Oncogene Proteins c-mdm2
  • USP7 protein, human
  • Ubiquitin Thiolesterase
  • Ubiquitin-Specific Peptidase 7
  • Carbon-Nitrogen Ligases
  • GMP synthase (glutamine-hydrolyzing)

Associated data

  • PDB/2YLM