Identification of phosphorylated sites in the mouse glucocorticoid receptor.

摘要: Glucocorticoid receptors in vivo are phosphorylated the absence of hormone and become hyperphosphorylated presence glucocorticoid agonist but not antagonists (Orti, E., Mendel, D.B., Smith, L.I., Munck, A. (1989) J. Biol. Chem. 264, 9728-9731). As a preliminary step to elucidating functional significance receptor phosphorylation, we have identified seven sites on mouse receptor. Tryptic phosphopeptides from 32P-labeled were purified glucocorticoid-treated thymoma cells (WEHI-7) stably transfected Chinese hamster ovary (WCL2) that express large numbers receptors. Phosphopeptide maps these two cell types almost indistinguishable. Solid phase sequencing revealed phosphorylation at serines 122, 150, 212, 220, 234, 315 threonine 159. Serines 234 sequences surrounding them conserved homologous regions rat human receptors, 159 serine no homologues The amino-terminal domain All within transactivation domains and/or highly acidic region is necessary for full transcription initiation activity reduces nonspecific DNA binding. consensus proline-directed kinase p34cdc2 kinase. Serine 122 sequence casein II whereas 150 do appear be any known sequence. location many suggests role transactivation.