Protein-tyrosine kinase Pyk2 is involved in interleukin-2 production by Jurkat T cells via its tyrosine 402

J Biol Chem. 2000 Jun 30;275(26):19645-52. doi: 10.1074/jbc.M909828199.

Abstract

We established Jurkat transfectants that overexpress Pyk2 or its mutants, K457A (lysine 457 was mutated to alanine), Pyk2-Y402F (tyrosine 402 to phenylalanine), and Pyk2-Y881F to investigate the role of Pyk2 in T cell activation. Pyk2 as well as kinase-inactive Pyk2-K457A, was phosphorylated at tyrosine residues 402, 580, and 881 upon T cell antigen receptor cross-linking, indicating that these residues are phosphorylated by other tyrosine kinase(s). However, no tyrosine phosphorylation of Pyk2-Y402F was detected while more than 60% of the tyrosine phosphorylation was observed in Pyk2-Y881F. Pyk2-Y402F inhibited the activation of endogenous Pyk2. The degree of activation of both c-Jun NH(2)-terminal kinase and p38 mitogen-activated protein kinase but not extracellular signal-regulated protein kinase after concurrent ligation of T cell antigen receptor and CD28 was reduced by more than 50% in the clones expressing Pyk2-Y402F. Consistent with this inhibition, IL-2 production was significantly diminished in the Pyk2-Y402F-expressing clones. Furthermore, we found that Pyk2, when overexpressed, associates with Zap70 and Vav. Taken together, these findings suggest that Pyk2 is involved in the activation of T cells through its tyrosine 402.

MeSH terms

  • CD28 Antigens / metabolism
  • Cell Cycle Proteins*
  • Enzyme Activation
  • Focal Adhesion Kinase 2
  • Glutathione Transferase / metabolism
  • Humans
  • Interleukin-2 / biosynthesis*
  • JNK Mitogen-Activated Protein Kinases*
  • Jurkat Cells
  • Lymphocyte Activation*
  • MAP Kinase Kinase 4
  • Mitogen-Activated Protein Kinase Kinases / metabolism
  • Mitogen-Activated Protein Kinases / metabolism
  • Mutation
  • Phosphorylation
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism*
  • Protein-Tyrosine Kinases / physiology*
  • Proto-Oncogene Proteins / metabolism
  • Proto-Oncogene Proteins c-vav
  • Receptors, Antigen, T-Cell / metabolism
  • Recombinant Fusion Proteins / metabolism
  • T-Lymphocytes / metabolism*
  • Transfection
  • Tyrosine / metabolism*
  • ZAP-70 Protein-Tyrosine Kinase
  • p38 Mitogen-Activated Protein Kinases

Substances

  • CD28 Antigens
  • Cell Cycle Proteins
  • Interleukin-2
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-vav
  • Receptors, Antigen, T-Cell
  • Recombinant Fusion Proteins
  • VAV1 protein, human
  • Tyrosine
  • Glutathione Transferase
  • Protein-Tyrosine Kinases
  • Focal Adhesion Kinase 2
  • ZAP-70 Protein-Tyrosine Kinase
  • ZAP70 protein, human
  • JNK Mitogen-Activated Protein Kinases
  • Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases
  • MAP Kinase Kinase 4
  • Mitogen-Activated Protein Kinase Kinases