Comment on "PDK1 nucleates T cell receptor-induced signaling complex for NF-kappaB activation".
We observe that protein kinase C (PKC) is phosphorylated on the activation loop at threonine 538 (Thr-538) before T cell activation. Our results are inconsistent with the conclusions of Lee et al. (Reports, 1 April 2005, p. 114) that the Thr-538 phosphorylation of PKC is regulated by T cell receptor activation. Other mechanisms, such as autophosphorylation of Thr-219, might orchestrate the cellular function of PKC in T cells.
Gruber
Thomas
T
Department for Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, Austria.
Freeley
Michael
M
Thuille
Nikolaus
N
Heit
Isabelle
I
Shaw
Stephen
S
Long
Aideen
A
Baier
Gottfried
G
D064413:3-Phosphoinositide-Dependent Protein Kinases; D000818:Animals; D000906:Antibodies / Q000276:immunology; D018106:CD28 Antigens / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D002478:Cells, Cultured; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism*; D019169:Jurkat Cells; D008213:Lymphocyte Activation; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism*; D000074121:Protein Kinase C-theta; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000201:enzymology / Q000276:immunology / Q000378:metabolism*; D013912:Threonine / Q000378:metabolism
D000906:Antibodies; D018106:CD28 Antigens; D017252:CD3 Complex; D007527:Isoenzymes; D016328:NF-kappa B; D011948:Receptors, Antigen, T-Cell; D013912:Threonine; D064413:3-Phosphoinositide-Dependent Protein Kinases; C578562:PDPK1 protein, human; C578564:Pdpk1 protein, mouse; D017346:Protein Serine-Threonine Kinases; C076233:PRKCQ protein, human; C489593:Prkcq protein, mouse; D011493:Protein Kinase C; D000074121:Protein Kinase C-theta