Becker Matthias, Baumann Christopher, John Sam, Walker Dawn A, Vigneron Marc, McNally James G, Hager Gordon L
Laboratory of Receptor Biology and Gene Expression, Building 41 Room B602, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-5055, USA.
EMBO Rep. 2002 Dec;3(12):1188-94. doi: 10.1093/embo-reports/kvf244. Epub 2002 Nov 21.
Through the use of photobleaching techniques, we examined the dynamic interaction of three members of the transcription apparatus with a target promoter in living cells. The glucocorticoid receptor (GR) interacting protein 1 (GRIP-1) exhibits a half maximal time for fluorescent recovery (tau(R)) of 5 s, reflecting the same rapid exchange as observed for GR. In contrast, the large subunit (RPB1) of RNA polymerase II (pol II) required 13 min for complete fluorescence recovery, consistent with its function as a processive enzyme. We also observe a complex induction profile for the kinetics of GR-stimulated transcription. Our results indicate that GR and GRIP-1 as components of the activating complex are in a dynamic equilibrium with the promoter, and must return to the template many times during the course of transcriptional activation.
通过使用光漂白技术，我们研究了转录装置的三个成员与活细胞中目标启动子的动态相互作用。糖皮质激素受体（GR）相互作用蛋白1（GRIP - 1）的荧光恢复半衰期（tau(R)）为5秒，这反映出与GR相同的快速交换。相比之下，RNA聚合酶II（pol II）的大亚基（RPB1）需要13分钟才能完全恢复荧光，这与其作为持续性酶的功能一致。我们还观察到GR刺激转录动力学的复杂诱导模式。我们的结果表明，作为激活复合物组分的GR和GRIP - 1与启动子处于动态平衡，并且在转录激活过程中必须多次返回模板。
