Denner L A, Weigel N L, Maxwell B L, Schrader W T, O'Malley B W
Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030.
Science. 1990 Dec 21;250(4988):1740-3. doi: 10.1126/science.2176746.
The progesterone receptor (PR) in the chicken oviduct is a phosphoprotein that regulates gene transcription in the presence of progesterone. Treatment with progesterone in vivo stimulates phosphorylation of the progesterone receptor. With transient transfection assays, the present work has tested whether phosphorylation participates in the regulation of PR-mediated transcription. Treatment with 8-bromo-cyclic adenosine monophosphate (8-Br cAMP), a stimulator of cAMP-dependent protein kinase [protein kinase A (PKA)], mimicked progesterone-dependent, receptor-mediated transcription in the absence of progesterone. Inhibition of PKA blocked hormone action. Treatment with okadaic acid, an inhibitor of protein phosphatases 1 and 2A, stimulated transcription in a manner similar to that of progesterone. These observations suggest that phosphorylation of the PR or other proteins in the transcription complex can modulate PR-mediated transcription in vivo.
鸡输卵管中的孕酮受体（PR）是一种磷蛋白，在孕酮存在的情况下调节基因转录。体内用孕酮处理可刺激孕酮受体的磷酸化。通过瞬时转染分析，本研究检测了磷酸化是否参与PR介导的转录调控。用8-溴环磷酸腺苷（8-Br cAMP）处理，它是一种环磷酸腺苷依赖性蛋白激酶[蛋白激酶A（PKA）]的刺激剂，在没有孕酮的情况下模拟了孕酮依赖性、受体介导的转录。抑制PKA可阻断激素作用。用冈田酸处理，它是蛋白磷酸酶1和2A的抑制剂，以类似于孕酮的方式刺激转录。这些观察结果表明，PR或转录复合物中其他蛋白质的磷酸化可在体内调节PR介导的转录。
