Cdk1 Triggers Association of RNA Polymerase to Cell Cycle Promoters Only after Recruitment of the Mediator by SBF.
Cdk1 Triggers Association of RNA Polymerase to Cell Cycle Promoters Only after Recruitment of the Mediator by SBF.
复制标题
DOI：
10.1016/j.molcel.2016.07.002
复制
发表时间：
2016
期刊：
影响因子：
16
通讯作者：
M. Cosma;Silvia Panizza;K. Nasmyth
中科院分区：
文献类型：
--
作者：
M. Cosma;Silvia Panizza;K. Nasmyth
酵母中HO的激活涉及两波转录因子的募集。第一种是由有丝分裂结束时Cdk 1的失活触发的，这促进了Swi 5转录因子进入细胞核。Swi 5募集Swi/Snf染色质重塑复合物，然后促进佐贺组蛋白乙酰化酶的募集，这反过来又允许SBF转录因子的结合。我们在这里表明，SBF，然后招聘SRB/介质复合物，这一过程中发生的Cdk 1活性的情况下。第二波由Cdk 1的重新激活触发，这导致PolII，TFIIB和TFIIH的招募。因此，RNA聚合酶在两个步骤中被募集到HO，而不是作为全酶。类似的事件发生在其他SBF调控的启动子上，如CLN 1、CLN 2和PCL 1。
Activation ofHOin yeast involves recruitment of transcription factors in two waves. The first is triggered by inactivation of Cdk1 at the end of mitosis, which promotes import into the nucleus of the Swi5 transcription factor. Swi5 recruits the Swi/Snf chromatin-remodeling complex, which then facilitates recruitment of the SAGA histone acetylase, which in turn permits the binding of the SBF transcription factor. We show here that SBF then recruits the SRB/mediator complex and that this process occurs in the absence of Cdk1 activity. The second wave is triggered by reactivation of Cdk1, which leads to recruitment of PolII, TFIIB, and TFIIH. RNA polymerase is, therefore, recruited toHOin two steps and not as a holoenzyme. A similar sequence of events occurs at other SBF-regulated promoters, such asCLN1,CLN2, andPCL1.