Src homology 2 domain-containing leukocyte phosphoprotein of 76 kDa and phospholipase C gamma 1 are required for NF-kappa B activation and lipid raft recruitment of protein kinase C theta induced by T cell costimulation.
The NF-kappaB activation pathway induced by T cell costimulation uses various molecules including Vav1 and protein kinase C (PKC)theta. Because Vav1 inducibly associates with further proteins including phospholipase C (PLC)gamma1 and Src homology 2 domain-containing leukocyte phosphoprotein of 76 kDa (SLP-76), we investigated their role for NF-kappaB activation in Jurkat leukemia T cell lines deficient for expression of these two proteins. Cells lacking SLP-76 or PLCgamma1 failed to activate NF-kappaB in response to T cell costimulation. In contrast, replenishment of SLP-76 or PLCgamma1 expression restored CD3/CD28-induced IkappaB kinase (IKK) activity as well as NF-kappaB DNA binding and transactivation. PKCtheta activated NF-kappaB in SLP-76- and PLCgamma1-deficient cells, showing that PKCtheta is acting further downstream. In contrast, Vav1-induced NF-kappaB activation was normal in SLP-76(-) cells, but absent in PLCgamma1(-) cells. CD3/CD28-stimulated recruitment of PKCtheta and IKKgamma to lipid rafts was lost in SLP-76- or PLCgamma1-negative cells, while translocation of Vav1 remained unaffected. Accordingly, recruitment of PKCtheta to the immunological synapse strictly relied on the presence of SLP-76 and PLCgamma1, but synapse translocation of Vav1 identified in this study was independent from both proteins. These results show the importance of SLP-76 and PLCgamma1 for NF-kappaB activation and raft translocation of PKCtheta and IKKgamma.
Dienz
Oliver
O
Division of Immunochemistry, German Cancer Research Center (Deutsches Krebsforschungszentrum), Im Neuenheimer Feld, Heidelberg, Germany.
Möller
Andreas
A
Strecker
Andreas
A
Stephan
Nadja
N
Krammer
Peter H
PH
Dröge
Wulf
W
Schmitz
M Lienhard
ML
D048868:Adaptor Proteins, Signal Transducing; D018106:CD28 Antigens / Q000494:pharmacology; D017252:CD3 Complex / Q000494:pharmacology; D018797:Cell Cycle Proteins; D006801:Humans; D051550:I-kappa B Kinase; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000235:genetics; D021962:Membrane Microdomains / Q000201:enzymology* / Q000235:genetics; D016328:NF-kappa B / Q000096:biosynthesis / Q000378:metabolism*; D051966:Phospholipase C gamma; D010750:Phosphoproteins / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D011493:Protein Kinase C / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D000074121:Protein Kinase C-theta; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D021381:Protein Transport / Q000235:genetics / Q000276:immunology; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000378:metabolism; D051567:Proto-Oncogene Proteins c-vav; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D014162:Transfection; D010738:Type C Phospholipases / Q000235:genetics / Q000502:physiology*; D018909:src Homology Domains / Q000235:genetics / Q000276:immunology*
D048868:Adaptor Proteins, Signal Transducing; D018106:CD28 Antigens; D017252:CD3 Complex; D018797:Cell Cycle Proteins; D007527:Isoenzymes; D016328:NF-kappa B; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; D051567:Proto-Oncogene Proteins c-vav; C092947:SLP-76 signal Transducing adaptor proteins; C496618:VAV1 protein, human; D017346:Protein Serine-Threonine Kinases; C496559:CHUK protein, human; D051550:I-kappa B Kinase; C496560:IKBKB protein, human; C496565:IKBKE protein, human; C076233:PRKCQ protein, human; D011493:Protein Kinase C; D000074121:Protein Kinase C-theta; D010738:Type C Phospholipases; D051966:Phospholipase C gamma