Variable effects of phosphorylation of Pit-1 dictated by the DNA response elements.
Pit-1, a tissue-specific POU domain transcription factor, is required for the activation of the prolactin, growth hormone, and Pit-1 promoters that confer regulation by epidermal growth factor, adenosine 3',5'-monophosphate (cAMP), and phorbol esters. Pit-1 is phosphorylated in pituitary cells at two distinct sites in response to phorbol esters and cAMP. Phosphorylation of Pit-1 modifies its conformation on DNA recognition elements and results in increased binding at certain sites and decreased binding at other sites, dependent on DNA sequences adjacent to the core Pit-1 binding motif. One residue (Thr220), located in the POU homeodomain within a sequence conserved throughout the POU-domain family, confers these responses.
Kapiloff
M S
MS
Eukaryotic Regulatory Biology Program, School of Medicine, University of California, San Diego, La Jolla 92093-0648.
Farkash
Y
Y
Wegner
M
M
Rosenfeld
M G
MG
D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D000242:Cyclic AMP / Q000494:pharmacology; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000502:physiology*; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D010766:Phosphorylation; D010769:Phosphothreonine / Q000378:metabolism; D010902:Pituitary Gland / Q000502:physiology*; D011494:Protein Kinases / Q000378:metabolism; D012045:Regulatory Sequences, Nucleic Acid; D013329:Structure-Activity Relationship; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D050817:Transcription Factor Pit-1; D014157:Transcription Factors / Q000737:chemistry / Q000502:physiology*; D014357:Trypsin
D004268:DNA-Binding Proteins; D050817:Transcription Factor Pit-1; D014157:Transcription Factors; D010769:Phosphothreonine; D004247:DNA; D000242:Cyclic AMP; D011494:Protein Kinases; D014357:Trypsin; D013755:Tetradecanoylphorbol Acetate