The structure of rat ADP-ribosylation factor-1 (ARF-1) complexed to GDP determined from two different crystal forms

Nat Struct Biol. 1995 Sep;2(9):797-806. doi: 10.1038/nsb0995-797.


The ARFs are a family of 21,000 M(r) proteins with biological roles in constitutive secretion and activation of phospholipase D. The structure of ARF-1 complexed to GDP determined from two crystal forms reveals a topology that is similar to that of the protein p21 ras with two differences: an additional amino-terminal helix and an extra beta-strand. The Mg2+ ion in ARF-1 displays a five-coordination sphere; this feature is not seen in p21 ras, due to a shift in the relative position of the DXXG motif between the two proteins. The occurrence of a dimer in one crystal form suggests that ARF-1 may dimerize during its biological function. The dimer interface involves a region of the ARF-1 molecule that is analogous to the effector domain in p21 ras and may mediate interactions with its effectors.

Publication types

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

MeSH terms

  • ADP-Ribosylation Factors
  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Cell Membrane / chemistry
  • Crystallography, X-Ray
  • GTP-Binding Proteins / chemistry*
  • GTP-Binding Proteins / metabolism*
  • Guanosine Diphosphate / chemistry*
  • Guanosine Diphosphate / metabolism*
  • Humans
  • Magnesium / metabolism
  • Models, Chemical
  • Molecular Sequence Data
  • Protein Conformation
  • Protein Folding
  • Proto-Oncogene Proteins p21(ras) / chemistry
  • Rats


  • Guanosine Diphosphate
  • GTP-Binding Proteins
  • ADP-Ribosylation Factors
  • HRAS protein, human
  • Proto-Oncogene Proteins p21(ras)
  • Magnesium