Mammalian Ras interacts directly with the serine/threonine kinase Raf

Cell. 1993 Jul 16;74(1):205-14. doi: 10.1016/0092-8674(93)90307-c.


We have identified proteins that interact with H-Ras using a two hybrid system screen of a mouse cDNA library. Approximately 50% of the clones identified encoded portions of the c-Raf and A-Raf serine/threonine kinases. Overlaps among these clones define a conserved 81 residue region of the N-terminus of Raf as the Ras interaction region. We show that Raf interacts with wild-type and activated Ras, but not with an effector domain mutant of Ras or with a dominant-interfering Ras mutant. Using purified bacterially expressed fusion proteins, we show, furthermore, that Ras and the N-terminal region of Raf associate directly in vitro and that this interaction is dependent on GTP bound to Ras.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Binding Sites
  • DNA
  • Genes, ras
  • Guanosine Triphosphate / metabolism*
  • Mice
  • Molecular Sequence Data
  • Protein-Serine-Threonine Kinases / metabolism*
  • Proto-Oncogene Proteins / metabolism*
  • Proto-Oncogene Proteins c-raf
  • Proto-Oncogene Proteins p21(ras) / metabolism*
  • Recombinant Fusion Proteins / metabolism
  • Saccharomyces cerevisiae
  • Sequence Homology, Amino Acid


  • Proto-Oncogene Proteins
  • Recombinant Fusion Proteins
  • Guanosine Triphosphate
  • DNA
  • Protein-Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-raf
  • Proto-Oncogene Proteins p21(ras)