H4 replication-dependent diacetylation and Hat1 promote S-phase chromatin assembly in vivo
H4 replication-dependent diacetylation and Hat1 promote S-phase chromatin assembly in vivo
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DOI：
10.1091/mbc.e10-07-0633
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发表时间：
2011-01-15
影响因子：
3.3
通讯作者：
Thiriet, Christophe
中科院分区：
文献类型：
--
作者：
Ejlassi-Lassallette, Aida;Mocquard, Eloise;Thiriet, Christophe
虽然特定的翻译后修饰模式内的H3和H4尾部结构域与S-相关联，其在复制依赖的染色质组装的实际功能尚未被定义。在这里，我们使用的自然同步macroplasmodia多头绒泡菌重组蛋白的微量掺入检查H3和H4尾域的复制耦合染色质组装的功能。我们发现缺乏H4尾结构域的H3/H4复合物在细胞核中不能有效地回收，而H3尾结构域的缺失并不妨碍细胞核输入，但染色质组装失败。此外，我们的研究结果表明，正确的模式乙酰化的H4尾部结构域所需的核输入和染色质组装。这很可能是由于Hat 1的结合，因为共免疫沉淀实验显示Hat 1与细胞质中的预沉积组蛋白和复制染色质相关。这些结果表明，B型组蛋白乙酰转移酶协助H3/H4复合物从细胞质穿梭到复制叉。
While specific posttranslational modification patterns within the H3 and H4 tail domains are associated with the S-phase, their actual functions in replication-dependent chromatin assembly have not yet been defined. Here we used incorporation of trace amounts of recombinant proteins into naturally synchronous macroplasmodia of Physarum polycephalum to examine the function of H3 and H4 tail domains in replication-coupled chromatin assembly. We found that the H3/H4 complex lacking the H4 tail domain was not efficiently recovered in nuclei, whereas depletion of the H3 tail domain did not impede nuclear import but chromatin assembly failed. Furthermore, our results revealed that the proper pattern of acetylation on the H4 tail domain is required for nuclear import and chromatin assembly. This is most likely due to binding of Hat1, as coimmunoprecipitation experiments showed Hat1 associated with predeposition histones in the cytoplasm and with replicating chromatin. These results suggest that the type B histone acetyltransferase assists in shuttling the H3/H4 complex from cytoplasm to the replication forks.