Structure-function relationships of the G domain, a canonical switch motif

Annu Rev Biochem. 2011;80:943-71. doi: 10.1146/annurev-biochem-062708-134043.


GTP-binding (G) proteins constitute a class of P-loop (phosphate-binding loop) proteins that work as molecular switches between the GDP-bound OFF and the GTP-bound ON state. The common principle is the 160-180-residue G domain with an α,β topology that is responsible for nucleotide-dependent conformational changes and drives many biological functions. Although the G domain uses a universally conserved switching mechanism, its structure, function, and GTPase reaction are modified for many different pathways and processes.

Publication types

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

MeSH terms

  • Amino Acid Motifs*
  • Binding Sites
  • Crystallography, X-Ray
  • GTP-Binding Proteins / chemistry*
  • GTP-Binding Proteins / genetics
  • GTP-Binding Proteins / metabolism*
  • Guanosine Diphosphate / chemistry
  • Guanosine Diphosphate / metabolism
  • Guanosine Triphosphate / chemistry
  • Guanosine Triphosphate / metabolism
  • Humans
  • Models, Molecular
  • Molecular Sequence Data
  • Molecular Structure
  • Protein Multimerization
  • Protein Structure, Secondary*
  • Protein Structure, Tertiary*
  • Structure-Activity Relationship
  • Substrate Specificity


  • Guanosine Diphosphate
  • Guanosine Triphosphate
  • GTP-Binding Proteins