The nonhistone, N-terminal tail of an essential, chimeric H2A variant regulates mitotic H3-S10 dephosphorylation.
The nonhistone, N-terminal tail of an essential, chimeric H2A variant regulates mitotic H3-S10 dephosphorylation.
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DOI：
10.1101/gad.182683.111
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发表时间：
2012-03
影响因子：
10.5
通讯作者：
Xiaoyuan Song;J. Bowen;W. Miao;Yifan Liu;M. Gorovsky
中科院分区：
文献类型：
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作者：
Xiaoyuan Song;J. Bowen;W. Miao;Yifan Liu;M. Gorovsky
H2A.Y是嗜热四膜虫的一个重要的、趋异的组蛋白变体。它有一个很长的非组蛋白N末端，含有富含亮氨酸的重复序列（LRR）和一个LRR帽结构域，与细胞核中酵母蛋白磷酸酶1（PP 1）活性的调节因子Sds 22 p相似。在生长的细胞中，H2A.Y仅在S期掺入微核，S期在微核有丝分裂后立即发生。H2A.Y的消耗导致有丝分裂相关的组蛋白H3-S10磷酸化和模拟S10 E突变的有丝分裂异常的延长保留。在其中H2A.Y被耗尽的细胞中，其中H2A.Y N末端连接到H2A.X的诱导型嵌合基因显示出调节微核H3-S10磷酸化。H2A.Y还可以与四膜虫PP 1直系同源物（Ppo 1 p）特异性共免疫沉淀。综上所述，这些结果表明H2A.Y的N末端具有调节H3-S10去磷酸化的功能。H2 A变体和另一组蛋白的特定翻译后修饰之间的这种引人注目的体内“串扰”情况证明了组蛋白变体的新功能。
H2A.Y is an essential, divergent Tetrahymena thermophila histone variant. It has a long nonhistone N terminus that contains leucine-rich repeats (LRR) and an LRR cap domain with similarity to Sds22p, a regulator of yeast protein phosphatase 1 (PP1) activity in the nucleus. In growing cells, H2A.Y is incorporated into micronuclei only during S phase, which occurs immediately after micronuclear mitosis. Depletion of H2A.Y causes prolonged retention of mitosis-associated histone H3-S10 phosphorylation and mitotic abnormalities that mimic S10E mutation. In cells where H2A.Y is depleted, an inducible chimeric gene, in which the H2A.Y N terminus is attached to H2A.X, is shown to regulate micronuclear H3-S10 phosphorylation. H2A.Y can also be specifically coimmunoprecipitated with a Tetrahymena PP1 ortholog (Ppo1p). Taken together, these results argue that the N terminus of H2A.Y functions to regulate H3-S10 dephosphorylation. This striking in vivo case of "cross-talk" between a H2A variant and a specific post-translational modification of another histone demonstrates a novel function for a histone variant.