Group of Transcriptional Complexes Dynamics, Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia.
Group of Studying an Association of Transcription and mRNA Transport, Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia.
Biochim Biophys Acta Gene Regul Mech. 2018 Feb;1861(2):178-189. doi: 10.1016/j.bbagrm.2018.01.016. Epub 2018 Feb 6.
Transcriptional activation is often represented as a "one-step process" that involves the simultaneous recruitment of co-activator proteins, leading to a change in gene status. Using Drosophila developmental ecdysone-dependent genes as a model, we demonstrated that activation of transcription is instead a continuous process that consists of a number of steps at which different phases of transcription (initiation or elongation) are stimulated. Thorough evaluation of the behaviour of multiple transcriptional complexes during the early activation process has shown that the pathways by which activation proceeds for different genes may vary considerably, even in response to the same induction signal. RNA polymerase II recruitment is an important step that is involved in one of the pathways. RNA polymerase II recruitment is accompanied by the recruitment of a significant number of transcriptional coactivators as well as slight changes in the chromatin structure. The second pathway involves the stimulation of transcriptional elongation as its key step. The level of coactivator binding to the promoter shows almost no increase, whereas chromatin modification levels change significantly.
转录激活通常被表示为一个“单步过程”，涉及共激活蛋白的同时招募，导致基因状态的改变。我们使用果蝇发育蜕皮激素依赖基因作为模型，证明转录的激活实际上是一个连续的过程，由多个步骤组成，其中转录的不同阶段（起始或延伸）被刺激。对早期激活过程中多个转录复合物行为的彻底评估表明，不同基因的激活途径可能有很大差异，即使是响应相同的诱导信号也是如此。RNA 聚合酶 II 的募集是一个重要的步骤，它涉及其中一个途径。RNA 聚合酶 II 的募集伴随着大量转录共激活因子的募集以及染色质结构的轻微变化。第二个途径涉及转录延伸的刺激作为其关键步骤。共激活因子与启动子的结合水平几乎没有增加，而染色质修饰水平则发生显著变化。
