Abstract
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.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Amino Acid Sequence
-
Animals
-
B-Lymphocytes / metabolism
-
Cells, Cultured
-
DNA-Binding Proteins*
-
Gene Expression Regulation*
-
HeLa Cells
-
Homeodomain Proteins / metabolism
-
Host Cell Factor C1
-
Humans
-
Immunosuppressive Agents / pharmacology
-
Ionomycin / pharmacology
-
Jurkat Cells
-
Lymphocyte Activation*
-
Mice
-
Molecular Sequence Data
-
Octamer Transcription Factor-1
-
Phosphorylation
-
Phosphoserine / metabolism
-
Recombinant Fusion Proteins / metabolism
-
T-Lymphocytes / immunology
-
T-Lymphocytes / metabolism*
-
Tetradecanoylphorbol Acetate / pharmacology
-
Trans-Activators / genetics
-
Trans-Activators / metabolism*
-
Transcription Factors / metabolism
-
Transcriptional Activation*
Substances
-
DNA-Binding Proteins
-
HCFC1 protein, human
-
Hcfc1 protein, mouse
-
Homeodomain Proteins
-
Host Cell Factor C1
-
Immunosuppressive Agents
-
Octamer Transcription Factor-1
-
POU2AF1 protein, human
-
POU2F1 protein, human
-
Pou2af1 protein, mouse
-
Pou2f1 protein, mouse
-
Recombinant Fusion Proteins
-
Trans-Activators
-
Transcription Factors
-
Phosphoserine
-
Ionomycin
-
Tetradecanoylphorbol Acetate