Centromere transcription allows CENP-A to transit from chromatin association to stable incorporation.
Centromere transcription allows CENP-A to transit from chromatin association to stable incorporation.
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DOI：
10.1083/jcb.201611087
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发表时间：
2018-06-04
期刊：
影响因子：
--
通讯作者：
Heun P
中科院分区：
文献类型：
--
作者：
Bobkov GOM;Gilbert N;Heun P
转录如何对着丝粒组蛋白CENP-A的加载起作用尚不清楚。Bobkov等人。报道称，转录介导的染色质重塑使着丝粒CENP-A从染色质结合到核小体完全结合的转变。着丝粒是染色体分离所必需的，由组蛋白H3突变体CENP-A的存在在表观遗传学上指定。在果蝇和人类中，着丝粒标记的补充与DNA复制无关，需要移除H3的“占位符”核小体。尽管着丝粒的转录以前与新的CENP-A的负载有关，但其潜在的分子机制仍然知之甚少。在这里，我们使用果蝇组织培养细胞来表明，活跃转录的RNA聚合酶II的着丝粒存在与dCENP-A的从头沉积在时间上是一致的。利用一个新开发的不依赖于急性转录的dCENP-A装载系统，我们发现短暂的转录抑制会损害dCENP-A进入染色质的能力。有趣的是，dCENP-A最初针对着丝粒的靶向没有受到影响，揭示了新加载的dCENP-A的两种稳定状态：与着丝粒的盐敏感结合和耐盐的染色质结合形式。这表明，dCENP-A向着丝粒完全结合的核小体的转变需要转录介导的染色质重塑。
How transcription contributes to the loading of the centromere histone CENP-A is unclear. Bobkov et al. report that transcription-mediated chromatin remodeling enables the transition of centromeric CENP-A from chromatin association to full nucleosome incorporation. Centromeres are essential for chromosome segregation and are specified epigenetically by the presence of the histone H3 variant CENP-A. In flies and humans, replenishment of the centromeric mark is uncoupled from DNA replication and requires the removal of H3 “placeholder” nucleosomes. Although transcription at centromeres has been previously linked to the loading of new CENP-A, the underlying molecular mechanism remains poorly understood. Here, we used Drosophila melanogaster tissue culture cells to show that centromeric presence of actively transcribing RNA polymerase II temporally coincides with de novo deposition of dCENP-A. Using a newly developed dCENP-A loading system that is independent of acute transcription, we found that short inhibition of transcription impaired dCENP-A incorporation into chromatin. Interestingly, initial targeting of dCENP-A to centromeres was unaffected, revealing two stability states of newly loaded dCENP-A: a salt-sensitive association with the centromere and a salt-resistant chromatin-incorporated form. This suggests that transcription-mediated chromatin remodeling is required for the transition of dCENP-A to fully incorporated nucleosomes at the centromere.
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DOI：
10.1083/jcb.201305036
发表时间：
2014-02-03
期刊：
The Journal of cell biology
影响因子：
--
作者：
Chen CC;Dechassa ML;Bettini E;Ledoux MB;Belisario C;Heun P;Luger K;Mellone BG
通讯作者：
Mellone BG
影响因子：
11.8
作者：
Chen, Chin-Chi;Bowers, Sarion;Lipinszki, Zoltan;Palladino, Jason;Trusiak, Sarah;Bettini, Emily;Rosin, Leah;Przewloka, Marcin R.;Glover, David M.;O'Neill, Rachel J.;Mellone, Barbara G.
通讯作者：
Mellone, Barbara G.
影响因子：
9.8
作者：
Dunleavy EM;Beier NL;Gorgescu W;Tang J;Costes SV;Karpen GH
通讯作者：
Karpen GH
DOI：
10.1073/pnas.172403699
发表时间：
2002-12-10
影响因子：
11.1
作者：
Ahmad, K;Henikoff, S
通讯作者：
Henikoff, S
影响因子：
4.5
作者：
Catania S;Pidoux AL;Allshire RC
通讯作者：
Allshire RC