ZAP-70 and SLP-76 regulate protein kinase C-theta and NF-kappa B activation in response to engagement of CD3 and CD28

J Immunol. 2001 May 1;166(9):5654-64. doi: 10.4049/jimmunol.166.9.5654.

Abstract

The transcription factor NF-kappaB is a critical regulator of T cell function that becomes strongly activated in response to coengagement of TCR and CD28. Although events immediately proximal to NF-kappaB activation are well understood, uncertainty remains over which upstream signaling pathways engaged by TCR and CD28 lead to NF-kappaB activation. By using Jurkat T cell lines that are deficient or replete for either the protein tyrosine kinase ZAP-70 or the cytosolic adapter molecule SLP-76, the role of these proteins in modulating NF-kappaB activation was examined. NF-kappaB was not activated in response to coengagement of TCR and CD28 in either the ZAP-70- or SLP-76-negative cells, whereas stimuli that bypass these receptors (PMA plus A23187, or TNF-alpha) activated NF-kappaB normally. Protein kinase C (PKC) theta activation, which is required for NF-kappaB activation, also was defective in these cells. Reexpression of ZAP-70 restored PKCtheta and NF-kappaB activation in response to TCR and CD28 coengagement. p95(vav) (Vav)-1 tyrosine phosphorylation was largely unperturbed in the ZAP-70-negative cells; however, receptor-stimulated SLP-76/Vav-1 coassociation was greatly reduced. Wild-type SLP-76 fully restored PKCtheta and NF-kappaB activation in the SLP-76-negative cells, whereas 3YF-SLP-76, which lacks the sites of tyrosine phosphorylation required for Vav-1 binding, only partially rescued signaling. These data illustrate the importance of the ZAP-70/SLP-76 signaling pathway in CD3/CD28-stimulated activation of PKC theta and NF-kappaB, and suggest that Vav-1 association with SLP-76 may be important in this pathway.

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • CD28 Antigens / immunology*
  • CD28 Antigens / metabolism*
  • CD3 Complex / immunology*
  • CD3 Complex / metabolism*
  • Calcimycin / pharmacology
  • Cell Cycle Proteins*
  • DNA-Binding Proteins / metabolism
  • Enzyme Activation / drug effects
  • Enzyme Activation / immunology
  • Humans
  • I-kappa B Proteins*
  • Ionophores / pharmacology
  • Isoenzymes / metabolism*
  • Jurkat Cells
  • Kinetics
  • Lymphocyte Activation / drug effects
  • Lymphocyte Activation / genetics
  • NF-KappaB Inhibitor alpha
  • NF-kappa B / antagonists & inhibitors
  • NF-kappa B / metabolism*
  • Phosphoproteins / deficiency
  • Phosphoproteins / genetics
  • Phosphoproteins / physiology*
  • Protein Kinase C / metabolism*
  • Protein Kinase C-theta
  • Protein-Tyrosine Kinases / biosynthesis
  • 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 / physiology
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / enzymology
  • T-Lymphocytes / metabolism
  • Tetradecanoylphorbol Acetate / pharmacology
  • Tyrosine / metabolism
  • ZAP-70 Protein-Tyrosine Kinase

Substances

  • Adaptor Proteins, Signal Transducing
  • CD28 Antigens
  • CD3 Complex
  • Cell Cycle Proteins
  • DNA-Binding Proteins
  • I-kappa B Proteins
  • Ionophores
  • Isoenzymes
  • NF-kappa B
  • NFKBIA protein, human
  • Phosphoproteins
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-vav
  • Receptors, Antigen, T-Cell
  • SLP-76 signal Transducing adaptor proteins
  • VAV1 protein, human
  • NF-KappaB Inhibitor alpha
  • Calcimycin
  • Tyrosine
  • Protein-Tyrosine Kinases
  • ZAP-70 Protein-Tyrosine Kinase
  • ZAP70 protein, human
  • PRKCQ protein, human
  • Protein Kinase C
  • Protein Kinase C-theta
  • Tetradecanoylphorbol Acetate