Residues Y429 and Y463 of the human CD5 are targeted by protein tyrosine kinases

Eur J Immunol. 2001 Apr;31(4):1191-8. doi: 10.1002/1521-4141(200104)31:4<1191::aid-immu1191>3.0.co;2-h.

Abstract

The human CD5 lymphocyte cell surface co-receptor modulates activation and differentiation responses mediated by the antigen-specific receptor of T and B cells. CD5 is phosphorylated following lymphocyte activation; however, the exact sites and kinases involved are yet to be determined. Jurkat T cell transfectants expressing tyrosine-mutated CD5 molecules have been used to show that residues Y429 and Y463 are targeted in vivo by protein tyrosine kinases following cell stimulation with anti-CD3 mAb or pervanadate. This is in agreement with data from direct in vitro kinase assays using purified recombinant Lck and Fyn protein tyrosine kinases. The analysis of Lck- and CD3-deficient Jurkat cells shows that tyrosine phosphorylation of CD5 requires Lck activity. We propose that T cell activation mediates CD5 tyrosine phosphorylation at residues Y429 and Y463 mainly through the activation of Lck.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Substitution / genetics
  • Antibodies, Monoclonal / immunology
  • Antibodies, Monoclonal / pharmacology
  • CD3 Complex / genetics
  • CD3 Complex / immunology
  • CD5 Antigens / chemistry
  • CD5 Antigens / genetics
  • CD5 Antigens / metabolism*
  • Enzyme Activation / drug effects
  • Humans
  • Jurkat Cells
  • Lymphocyte Activation / drug effects
  • Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / deficiency
  • Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / genetics
  • Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / metabolism
  • Mutation / genetics
  • Phosphorylation / drug effects
  • Phosphotyrosine / metabolism
  • Protein Tyrosine Phosphatases / antagonists & inhibitors
  • Protein-Tyrosine Kinases / deficiency
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism*
  • Proto-Oncogene Proteins / metabolism
  • Proto-Oncogene Proteins c-fyn
  • Recombinant Fusion Proteins / metabolism
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / enzymology
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism
  • Transfection
  • Tyrosine / genetics
  • Tyrosine / metabolism*
  • Vanadates / pharmacology

Substances

  • Antibodies, Monoclonal
  • CD3 Complex
  • CD5 Antigens
  • Proto-Oncogene Proteins
  • Recombinant Fusion Proteins
  • pervanadate
  • Phosphotyrosine
  • Vanadates
  • Tyrosine
  • Protein-Tyrosine Kinases
  • FYN protein, human
  • Lymphocyte Specific Protein Tyrosine Kinase p56(lck)
  • Proto-Oncogene Proteins c-fyn
  • Protein Tyrosine Phosphatases