GTPase-activating proteins: helping hands to complement an active site

Trends Biochem Sci. 1998 Jul;23(7):257-62. doi: 10.1016/s0968-0004(98)01224-9.


Stimulation of the intrinsic GTPase activity of GTP-binding proteins by GTPase-activating proteins (GAPs) is a basic principle of GTP-binding-protein downregulation. Recently, the molecular mechanism behind this reaction has been elucidated by studies on Ras and Rho, and their respective GAPs. The basic features involve stabilizing the existing catalytic machinery and supplementing it by an external arginine residue. This represents a novel mechanism for enzyme active-site formation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Enzyme Activation
  • GTP Phosphohydrolases / metabolism*
  • GTPase-Activating Proteins
  • Humans
  • Models, Biological
  • Models, Molecular
  • Protein Conformation
  • Proteins / chemistry
  • Proteins / genetics
  • Proteins / metabolism*
  • Sequence Homology, Amino Acid
  • ras GTPase-Activating Proteins


  • GTPase-Activating Proteins
  • Proteins
  • ras GTPase-Activating Proteins
  • GTP Phosphohydrolases