Epigenetically induced paucity of histone H2A. 2 stabilizes fission-yeast ectonic centoromeres
Epigenetically induced paucity of histone H2A. 2 stabilizes fission-yeast ectonic centoromeres
复制标题
表观遗传诱导组蛋白 H2A 缺乏。
DOI：
10.1038/nsmb.2697
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发表时间：
2013
影响因子：
16.8
通讯作者：
Ishii K
中科院分区：
文献类型：
--
作者：
Ogiyama Y;Ohno Y;Kubota Y;Ishii K
在大多数真核生物中，着丝粒由含有组蛋白H3变体着丝粒蛋白A（CENP-A）的核小体表观遗传学定义。特异性靶向CENP-A-加载分子伴侣的着丝粒是至关重要的稳定的着丝粒繁殖;然而，异位着丝粒（新着丝粒）的存在表明，这种分子伴侣可以在不同的染色质环境中发挥作用。负责在非着丝粒区域容纳CENP-A分子伴侣的机制知之甚少。在这里，我们报告了暂时的，不成熟的新着丝粒在裂殖酵母的鉴定，显示减少与CENP-A伴侣Scm 3的关联，由于组蛋白H2 A变体H2A.Z的持久性。收购后的相邻异染色质或搬迁的未成熟的neocentromeres亚端粒区，H2A.Z耗尽和Scm 3补充，从而导致随后的稳定的neocentromeres。这些发现为组蛋白变体介导的新着丝粒建立的表观遗传控制提供了新的见解。
In most eukaryotes, centromeres are epigenetically defined by nucleosomes that contain the histone H3 variant centromere protein A (CENP-A). Specific targeting of the CENP-A–loading chaperone to the centromere is vital for stable centromere propagation; however, the existence of ectopic centromeres (neocentromeres) indicates that this chaperone can function in different chromatin environments. The mechanism responsible for accommodating the CENP-A chaperone at noncentromeric regions is poorly understood. Here, we report the identification of transient, immature neocentromeres inSchizosaccharomyces pombethat show reduced association with the CENP-A chaperone Scm3, owing to persistence of the histone H2A variant H2A.Z. After the acquisition of adjacent heterochromatin or relocation of the immature neocentromeres to subtelomeric regions, H2A.Z was depleted and Scm3 was replenished, thus leading to subsequent stabilization of the neocentromeres. These findings provide new insights into histone variant–mediated epigenetic control of neocentromere establishment.