A molecular redox switch on p21(ras). Structural basis for the nitric oxide-p21(ras) interaction Academic Article uri icon


MeSH Major

  • Hernia, Obturator
  • Intestinal Obstruction


  • We have identified the site of molecular interaction between nitric oxide (NO) and p21(ras) responsible for initiation of signal transduction. We found that p21(ras) was singly S-nitrosylated and localized this modification to a fragment of p21(ras) containing Cys118. A mutant form of p21(ras), in which Cys118 was changed to a serine residue and termed p21(ras)C118S, was not S-nitrosylated. NO-related species stimulated guanine nucleotide exchange on wild-type p21(ras), resulting in an active form, but not on p21(ras)C118S. Furthermore, in contrast to parental Jurkat T cells, NO-related species did not stimulate mitogen-activated protein kinase activity in cells transfected with p21(ras)C118S. These data indicate that Cys118 is a critical site of redox regulation of p21(ras), and S-nitrosylation of this residue triggers guanine nucleotide exchange and downstream signaling.

publication date

  • February 25, 1997



  • Academic Article


Digital Object Identifier (DOI)

  • 10.1074/jbc.272.7.4323

Additional Document Info

start page

  • 4323

end page

  • 6


  • 272


  • 7