Chromatin inheritance upon Zeste-mediated Brahma recruitment at a minimal cellular memory module
Chromatin inheritance upon Zeste-mediated Brahma recruitment at a minimal cellular memory module
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DOI：
10.1038/sj.emboj.7600108
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发表时间：
2004-02-25
期刊：
影响因子：
11.4
通讯作者：
Cavalli, G
中科院分区：
文献类型：
--
作者：
Déjardin, J;Cavalli, G
Polycomb 组和 trithorax 组蛋白通过称为 Polycomb 和 trithorax 的 DNA 序列调节其靶基因的染色质，从而维持抑制和活跃染色质状态的记忆。响应元素。由于这些元件经常重叠，并且能够通过细胞分裂传递沉默和活跃染色质的记忆，因此它们也被定义为细胞记忆模块（CMM）。我们在此从果蝇 Fab-7 区域鉴定出 219 bp 的最小 CMM，该区域调节同源异型基因 Abdominal-B。该 CMM 传达了由胚胎转录激活脉冲诱导的活性染色质状态的遗传，通过招募 Trithorax 组蛋白 Trithorax (TRX) 和 Brahma (BRM)（参与染色质重塑的 SW12/SNF2 ATP 酶的果蝇同源物）。在这个 CMM 中，Zeste 蛋白的 DNA 结合位点对于通过 Zeste 依赖性 BRM 募集来继承活性染色质是必需的，而 TRX 即使在它们不存在的情况下也可以结合 CMM。因此，活性染色质状态的表观遗传涉及在 CMM 内间隔紧密但不同的位点招募多个协作染色质修饰复合物。
Polycomb group and trithorax group proteins maintain the memory of repressed and active chromatin states by regulating chromatin of their target genes via DNA sequences termed Polycomb- and trithorax. response elements. Since these elements often overlap and are able to convey the memory of both silent and active chromatin through cell division, they were also defined as cellular memory modules (CMMs). We identify here a minimal CMM of 219 bp from the Drosophila Fab-7 region that regulates the homeotic gene Abdominal-B. This CMM conveys the inheritance of active chromatin states induced by an embryonic pulse of transcriptional activation via recruitment of the trithorax group proteins Trithorax (TRX) and Brahma (BRM) the Drosophila homologue of the SW12/SNF2 ATPase involved in chromatin remodelling. Within this CMM, DNA-binding sites for the Zeste protein are necessary for the inheritance of active chromatin through Zeste-dependent recruitment of BRM, while TRX can bind the CMM even in their absence. Thus, epigenetic inheritance of active chromatin states involves the recruitment of multiple cooperative chromatin-modifying complexes at closely spaced but distinct sites within a CMM.