The histone H3/H4 chaperone CHAF1B prevents the mislocalization of CENP-A for chromosomal stability.
The histone H3/H4 chaperone CHAF1B prevents the mislocalization of CENP-A for chromosomal stability.
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DOI：
10.1242/jcs.260944
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发表时间：
2023-05-15
影响因子：
4
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中科院分区：
文献类型：
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将进化上保守的着丝粒组蛋白H3变体CENP-A的定位限制于着丝粒防止染色体不稳定性（CIN）。CENP-A在非着丝粒区域的错误定位导致酵母、苍蝇和人类细胞中的CIN。尽管CENP-A在癌症中的过表达和错误定位已有报道，但对其错误定位的机制仍知之甚少。在这里，我们使用基于成像的高通量RNAi筛选来确定防止HeLa细胞中过表达的YFP标记的CENP-A（YFP-CENP-A）错误定位的因素。在筛选的前五名候选者中-其消耗显示增加的核YFP-CENP-A荧光-是组蛋白伴侣CHAF 1B（或p60）和CHAF 1A（或p150）。后续验证和表征实验表明，CHAF 1B耗尽的细胞表现出CENP-A错误定位，CIN表型和染色质组分中CENP-A的富集增加。DAXX（一种组蛋白H3.3分子伴侣）的耗竭抑制CHAF 1B耗竭细胞中的CENP-A错误定位和CIN。我们提出，在CHAF 1B耗尽的细胞中，DAXX促进过度表达的CENP-A到非着丝粒区域的错误定位，导致CIN。总之，我们确定了CENP-A定位的调节因子，并确定了CHAF 1B在预防DAXX依赖性CENP-A错误定位和CIN中的作用。总结：组蛋白H3/H4分子伴侣CHAF 1B防止CENP-A错误定位到非着丝粒区域，从而防止染色体不稳定性。
Restricting the localization of the evolutionarily conserved centromeric histone H3 variant CENP-A to centromeres prevents chromosomal instability (CIN). The mislocalization of CENP-A to non-centromeric regions contributes to CIN in yeasts, flies and human cells. Even though overexpression and mislocalization of CENP-A have been reported in cancers, the mechanisms responsible for its mislocalization remain poorly understood. Here, we used an imaging-based high-throughput RNAi screen to identify factors that prevent mislocalization of overexpressed YFP-tagged CENP-A (YFP–CENP-A) in HeLa cells. Among the top five candidates in the screen – the depletion of which showed increased nuclear YFP–CENP-A fluorescence – were the histone chaperones CHAF1B (or p60) and CHAF1A (or p150). Follow-up validation and characterization experiments showed that CHAF1B-depleted cells exhibited CENP-A mislocalization, CIN phenotypes and increased enrichment of CENP-A in chromatin fractions. The depletion of DAXX, a histone H3.3 chaperone, suppressed CENP-A mislocalization and CIN in CHAF1B-depleted cells. We propose that in CHAF1B-depleted cells, DAXX promotes mislocalization of the overexpressed CENP-A to non-centromeric regions, resulting in CIN. In summary, we identified regulators of CENP-A localization and defined a role for CHAF1B in preventing DAXX-dependent CENP-A mislocalization and CIN. Summary: The histone H3/H4 chaperone CHAF1B prevents mislocalization of CENP-A to non-centromeric regions, thus preventing chromosomal instability.
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影响因子：
16
作者：
Hewawasam G;Shivaraju M;Mattingly M;Venkatesh S;Martin-Brown S;Florens L;Workman JL;Gerton JL
通讯作者：
Gerton JL
影响因子：
12.3
作者：
Boutros M;Brás LP;Huber W
通讯作者：
Huber W
影响因子：
14.9
作者：
Demirdizen, Engin;Spiller-Becker, Matthias;Erhardt, Sylvia
通讯作者：
Erhardt, Sylvia
影响因子：
10.5
作者：
Deyter GM;Biggins S
通讯作者：
Biggins S
影响因子：
3.8
作者：
Zhu, Qianzheng;Wani, Gulzar;Arab, Hany H.;Ei-Mahdy, Mohamed A.;Ray, Alo;Wani, Altaf A.
通讯作者：
Wani, Altaf A.