c-Kit-mediated overlapping and unique functional and biochemical outcomes via diverse signaling pathways

Mol Cell Biol. 2004 Feb;24(3):1401-10. doi: 10.1128/MCB.24.3.1401-1410.2004.

Abstract

A critical issue in understanding receptor tyrosine kinase signaling is the individual contribution of diverse signaling pathways in regulating cellular growth, survival, and migration. We generated a functionally and biochemically inert c-Kit receptor that lacked the binding sites for seven early signaling pathways. Restoring the Src family kinase (SFK) binding sites in the mutated c-Kit receptor restored cellular survival and migration but only partially rescued proliferation and was associated with the rescue of the Ras/mitogen-activated protein kinase, Rac/JNK kinase, and phosphatidylinositol 3-kinase (PI-3 kinase)/Akt pathways. In contrast, restoring the PI-3 kinase binding site in the mutated receptor did not affect cellular proliferation but resulted in a modest correction in cell survival and migration, despite a complete rescue in the activation of the PI-3 kinase/Akt pathway. Surprisingly, restoring the binding sites for Grb2, Grb7, or phospholipase C-gamma had no effect on cellular growth or survival, migration, or activation of any of the downstream signaling pathways. These results argue that SFKs play a unique role in the control of multiple cellular functions and in the activation of distinct biochemical pathways via c-Kit.

MeSH terms

  • Animals
  • Binding Sites
  • Cell Division / physiology
  • Cell Movement / physiology*
  • Cell Survival / physiology
  • Humans
  • Mitogen-Activated Protein Kinases / metabolism
  • Mutation
  • Phosphatidylinositol 3-Kinases / metabolism
  • Protein Serine-Threonine Kinases*
  • Proto-Oncogene Proteins / metabolism
  • Proto-Oncogene Proteins c-akt
  • Proto-Oncogene Proteins c-kit / genetics
  • Proto-Oncogene Proteins c-kit / metabolism*
  • Signal Transduction / physiology*
  • ras Proteins / metabolism

Substances

  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-kit
  • AKT1 protein, human
  • Protein Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-akt
  • Mitogen-Activated Protein Kinases
  • ras Proteins