Protein kinase Cbeta1, a major regulator of TCR-CD28-activated signal transduction leading to IL-2 gene transcription and secretion.
The aim of this study was to investigate the influence of protein kinase C (PKC) alpha and beta on the TCR-CD28-stimulated protein kinase cascades participating in regulation of IL-2 gene transcription and secretion. Inhibition of the synthesis of PKCalpha and beta by specific phosphorothioate-modified antisense oligonucleotides (ODN) resulted in suppression of phosphorylation and activation of Raf-1, mitogen-activated extracellular-regulated kinase kinases and extracellular-regulated kinases in stimulated Jurkat T cells. Furthermore, a marked reduction of IkappaB kinase-alpha-catalyzed IkappaBalpha phosphorylation was observed in both PKCalpha- and beta-specific antisense oligonucleotide-treated cells. In sharp contrast, TCR-CD28-stimulated phosphorylation and activation of the Jun-N-terminal kinase (JNK) cascade was specifically suppressed upon treatment with PKCbeta-specific antisense ODN, suggesting that PKCbeta was a specific upstream regulator of the JNK protein kinase cascade. Significant inhibition of high-affinity NF-AT binding and transactivation, IL-2 gene expression, reduction of IL-2 mRNA synthesis, and, most impressively, a complete suppression of IL-2 secretion were observed in PKCbeta antisense ODN-treated cells. The data indicate a highly specific function of PKCbeta for regulation of TCR-CD28 induced-signaling, IL-2 gene expression and secretion in Jurkat T cells.
Dreikhausen
Uschi E
UE
Institute of Pharmacology, Medical School Hannover, 30623 Hannover, Germany.
Gorf
Katrin
K
Resch
Klaus
K
Szamel
Marta
M
D000911:Antibodies, Monoclonal; D015153:Blotting, Western; D018106:CD28 Antigens / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D007376:Interleukin-2 / Q000235:genetics* / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases; D019169:Jurkat Cells; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism*; D064546:Protein Kinase C beta; D051571:Protein Kinase C-alpha; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D018106:CD28 Antigens; D020672:I-kappa B Proteins; D007376:Interleukin-2; D016376:Oligonucleotides, Antisense; D011948:Receptors, Antigen, T-Cell; D017346:Protein Serine-Threonine Kinases; C496628:PRKCA protein, human; D011493:Protein Kinase C; D064546:Protein Kinase C beta; D051571:Protein Kinase C-alpha; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases