Inducible expression and phosphorylation of coactivator BOB.1/OBF.1 in T cells.
BOB.1/OBF.1 is a transcriptional coactivator that is constitutively expressed in B cells and interacts with the Oct1 and Oct2 transcription factors. Upon activation of Jurkat T cells and primary murine thymocytes with phorbol esters and ionomycin, BOB.1/OBF.1 expression and transactivation function were induced. BOB.1/OBF.1 was phosphorylated at Ser184 both in vivo and in vitro, and this modification was required for inducible activation. Mutation of Ser184 also diminished transactivation function in B cells, suggesting that the activating phosphorylation that is inducible in T cells is constitutively present in B cells. Thus, BOB.1/OBF.1 is a transcriptional coactivator that is critically regulated by posttranslational modifications to mediate cell type-specific gene expression.
Zwilling
S
S
MSZ, Institut für Medizinische Strahlenkunde und Zellforschung, Universität Würzburg, Versbacher Strasse 5, 97078 Würzburg, Germany.
Dieckmann
A
A
Pfisterer
P
P
Angel
P
P
Wirth
T
T
D000595:Amino Acid Sequence; D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism; D002478:Cells, Cultured; D004268:DNA-Binding Proteins; D005786:Gene Expression Regulation; D006367:HeLa Cells; D018398:Homeodomain Proteins / Q000378:metabolism; D051863:Host Cell Factor C1; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D015759:Ionomycin / Q000494:pharmacology; D019169:Jurkat Cells; D008213:Lymphocyte Activation; D051379:Mice; D008969:Molecular Sequence Data; D050811:Octamer Transcription Factor-1; D010766:Phosphorylation; D010768:Phosphoserine / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism; D015533:Transcriptional Activation
D004268:DNA-Binding Proteins; C497692:HCFC1 protein, human; C497693:Hcfc1 protein, mouse; D018398:Homeodomain Proteins; D051863:Host Cell Factor C1; D007166:Immunosuppressive Agents; D050811:Octamer Transcription Factor-1; C091546:POU2AF1 protein, human; C494165:POU2F1 protein, human; C490424:Pou2af1 protein, mouse; C494166:Pou2f1 protein, mouse; D011993:Recombinant Fusion Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D010768:Phosphoserine; D015759:Ionomycin; D013755:Tetradecanoylphorbol Acetate