Targeted recruitment of set1 histone methylase by elongating pol II provides a localized mark and memory of recent transcriptional activity
Targeted recruitment of set1 histone methylase by elongating pol II provides a localized mark and memory of recent transcriptional activity
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DOI：
10.1016/s1097-2765(03)00092-3
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发表时间：
2003-03-01
期刊：
影响因子：
16
通讯作者：
Struhl, K
中科院分区：
文献类型：
--
作者：
Ng, HH;Robert, F;Struhl, K
Set1是酵母组蛋白H3 - 赖氨酸4（H3 - K4）甲基转移酶，它被RNA聚合酶II（Pol II）延伸机制招募到活性mRNA编码区5'部分的一个高度局部化的区域。Set1的结合依赖于与转录因子IIH（TFIIH）相关的激酶，该激酶使Pol II的羧基末端结构域（CTD）磷酸化，并介导起始和延伸之间的转换，而且Set1与CTD在丝氨酸5而非丝氨酸2处磷酸化的Pol II形式相互作用。与Pol II相关的Paf1复合物中的Rtf1和Paf1组分对于Set1的招募也很重要。尽管二甲基化的H3 - K4水平在整个基因组中相当均匀，但三甲基化的H3 - K4模式与Set1的占位密切相关。在mRNA编码区内的高甲基化H3 - K4在转录失活以及Set1从染色质上解离后持续相当长的时间，这表明H3 - K4的高甲基化提供了近期转录活性的分子记忆。
Set1, the yeast histone H3-lysine 4 (H3-K4) methylase, is recruited by the Pol II elongation machinery to a highly localized domain at the 5' portion of active mRNA coding regions. Set1 association depends upon the TFIIH-associated kinase that phosphorylates the Pol II C-terminal domain (CTD) and mediates the transition between initiation and elongation, and Set1 interacts with the form of Pol II whose CTD is phosphorylated at serine 5 but not serine 2. The Rtf1 and Paf1 components of the Pol II-associated Paf1 complex are also important for Set1 recruitment. Although the level of dimethylated H3-K4 is fairly uniform throughout the genome, the pattern of trimethylated H3-K4 strongly correlates with Set1 occupancy. Hypermethylated H3-K4 within the mRNA coding region persists for considerable time after transcriptional inactivation and Set1 dissociation from the chromatin, indicating that H3-K4 hypermethylation provides a molecular memory of recent transcriptional activity.