Hepatocyte growth factor/scatter factor stimulates the Ras-guanine nucleotide exchanger

J Biol Chem. 1993 May 5;268(13):9165-8.

Abstract

Hepatocyte growth factor/scatter factor (HGF/SF) induces mitogenesis and cell dissociation upon binding to the protein-tyrosine kinase receptor encoded by the MET proto-oncogene (p190MET). The signal transduction pathways downstream from the receptor activation are largely unknown. We show that HGF/SF activates Ras protein. HGF/SF stimulation of metabolically labeled A549 cells raised the amount of Ras-bound radiolabeled guanine nucleotides by over 5-fold. Furthermore, following HGF/SF stimulation of these cells, 50% of Ras was in the GTP-bound active state. The uptake by Ras of radiolabeled GTP was also increased by 5-fold following HGF/SF stimulation in digitonin-permeabilized A549 cells. Moreover, HGF/SF treatment of A549 cells leads to stimulation of the cytosolic Ras-guanine nucleotide exchange activity, measured as accelerated release of [3H]GDP from purified recombinant Ras protein in vitro, in a dose- and time-dependent manner. Likewise, treatment with the protein-tyrosine kinase inhibitor 3-(1',4'-dihydroxytetralyl)methylene-2-oxindole of GTL-16 cells (featuring a p190MET receptor constitutively active) significantly decreased the cytosolic Ras-guanine nucleotide exchange activity. These data demonstrate that HGF/SF activates Ras protein by shifting the equilibrium toward the GTP-bound state and increases the uptake of guanine nucleotides by Ras, through mechanism(s) including the activation of a Ras-guanine nucleotide exchanger.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Transport / drug effects
  • Cell Line
  • GTPase-Activating Proteins
  • Guanosine Diphosphate / metabolism*
  • Guanosine Triphosphate / metabolism*
  • Hepatocyte Growth Factor / pharmacology*
  • Humans
  • Indoles / pharmacology*
  • Kinetics
  • Lung Neoplasms
  • Protein-Tyrosine Kinases / antagonists & inhibitors
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism*
  • Proteins / metabolism*
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins / metabolism*
  • Proto-Oncogene Proteins c-met
  • Proto-Oncogene Proteins p21(ras) / metabolism*
  • Proto-Oncogenes
  • Receptors, Cell Surface / drug effects
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / metabolism*
  • Recombinant Proteins / metabolism
  • Tetrahydronaphthalenes / pharmacology*
  • Tumor Cells, Cultured
  • ras GTPase-Activating Proteins

Substances

  • GTPase-Activating Proteins
  • Indoles
  • MAS1 protein, human
  • Proteins
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins
  • Receptors, Cell Surface
  • Recombinant Proteins
  • Tetrahydronaphthalenes
  • ras GTPase-Activating Proteins
  • Guanosine Diphosphate
  • Hepatocyte Growth Factor
  • Guanosine Triphosphate
  • Protein-Tyrosine Kinases
  • Proto-Oncogene Proteins c-met
  • HRAS protein, human
  • Proto-Oncogene Proteins p21(ras)