The Src and Csk families of tyrosine protein kinases in hemopoietic cells

Semin Immunol. 1995 Aug;7(4):207-26. doi: 10.1006/smim.1995.0026.


There is increasing evidence that the Src family of cytoplasmic tyrosine protein kinases is involved in the signal transduction of antigen receptor- and Fc receptor-mediated cellular activation. This function relates at least in part to the ability of Src-related enzymes to phosphorylate conserved tyrosine-based motifs in the cytoplasmic domains of the antigen and Fc receptors. The catalytic function of Src-like products is repressed by phosphorylation of a conserved carboxy-terminal tyrosine residue, which is mediated by another cellular tyrosine protein kinase, p50csk. Based on this property, it is postulated that Csk is a potent negative regulator of antigen and Fc receptor signalling. The balance between the actions of Src-related kinases and the p50csk is likely a major determinant of immune responsiveness.

Publication types

  • Review

MeSH terms

  • Animals
  • CSK Tyrosine-Protein Kinase
  • Hematopoietic Stem Cells / enzymology*
  • Humans
  • Protein-Tyrosine Kinases
  • Proto-Oncogene Proteins pp60(c-src)* / chemistry
  • Proto-Oncogene Proteins pp60(c-src)* / physiology
  • src-Family Kinases* / chemistry
  • src-Family Kinases* / physiology


  • Protein-Tyrosine Kinases
  • CSK Tyrosine-Protein Kinase
  • Proto-Oncogene Proteins pp60(c-src)
  • src-Family Kinases
  • CSK protein, human