The Raf-1 serine/threonine protein kinase

Semin Cancer Biol. 1994 Aug;5(4):247-53.


Raf-1 belongs to a family of serine/threonine protein kinases which are highly conserved through evolution in multicellular organisms. Raf-1 kinase has gained much attention due to its function as a critical shuttle enzyme that connects stimulation of growth factor receptors and protein kinase C at the cell membrane to changes in the expression of genes involved in the control of cell growth, differentiation and survival. Regulation of Raf-1 activity is complex and involves Ras, as well as several serine/threonine and tyrosine kinases. Through a series of phosphorylation events, extracellular signals are connected through the Raf-1/MAP kinase pathway to activity-regulation of several oncogene-class transcription factors via phosphorylation of specific serine residues. Under ordinary circumstances, the cascade involving Raf-1 eventually leads to changes in gene expression and protein synthesis. Upon constitutive activation of Raf-1 kinase, as a result of genetic changes, a variety of cell types acquire a transformed phenotype.

Publication types

  • Review

MeSH terms

  • Animals
  • Calcium-Calmodulin-Dependent Protein Kinases / physiology
  • Cyclic AMP-Dependent Protein Kinases / physiology
  • Genes, ras
  • Humans
  • Protein Kinase C / physiology
  • Protein-Serine-Threonine Kinases / physiology*
  • Proto-Oncogene Proteins / physiology*
  • Proto-Oncogene Proteins c-raf
  • Signal Transduction


  • Proto-Oncogene Proteins
  • Protein-Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-raf
  • Cyclic AMP-Dependent Protein Kinases
  • Protein Kinase C
  • Calcium-Calmodulin-Dependent Protein Kinases