A plant-specific SWR1 chromatin-remodeling complex couples histone H2A.Z deposition with nucleosome sliding
A plant-specific SWR1 chromatin-remodeling complex couples histone H2A.Z deposition with nucleosome sliding
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DOI：
10.15252/embj.2019102008
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发表时间：
2020-03-02
期刊：
影响因子：
11.4
通讯作者：
He, Xin-Jian
中科院分区：
文献类型：
--
作者：
Luo, Yu-Xi;Hou, Xiao-Mei;He, Xin-Jian
已知H2A.Z在染色质中的沉积由真核生物中保守的SWR 1染色质重塑复合物介导。然而，很少有人知道SWR 1复合物是否以及如何与其他染色质调控。使用免疫沉淀和质谱分析，我们发现了拟南芥SWR 1复合物的所有已知组分，并另外鉴定了以下三类以前未表征的植物特异性SWR 1组分：MBD 9，一种含有甲基-CpG结合结构域的蛋白质; CHR 11和CHR 17（CHR 11/17），负责核小体滑动的ISWI染色质重塑;以及TRA 1a和TRA 1b，保守的NuA 4组蛋白乙酰转移酶复合物的辅助亚基。MBD 9直接与CHR 11/17和SWR 1催化亚基PIE 1相互作用，并负责CHR 11/17与SWR 1复合物的缔合。MBD 9、TRA 1a和TRA 1b作为SWR 1复合物的典型组分起作用以介导H2A.Z沉积。CHR 11/17不仅负责核小体滑动，而且还参与H2A.Z沉积。这些结果表明，SWR 1复合物与CHR 11/17的关联可以促进H2A.Z沉积与核小体滑动的耦合，从而共调节基因表达、发育和开花时间。
Deposition of H2A.Z in chromatin is known to be mediated by a conserved SWR1 chromatin-remodeling complex in eukaryotes. However, little is known about whether and how the SWR1 complex cooperates with other chromatin regulators. Using immunoprecipitation followed by mass spectrometry, we found all known components of the Arabidopsis thaliana SWR1 complex and additionally identified the following three classes of previously uncharacterized plant-specific SWR1 components: MBD9, a methyl-CpG-binding domain-containing protein; CHR11 and CHR17 (CHR11/17), ISWI chromatin remodelers responsible for nucleosome sliding; and TRA1a and TRA1b, accessory subunits of the conserved NuA4 histone acetyltransferase complex. MBD9 directly interacts with CHR11/17 and the SWR1 catalytic subunit PIE1, and is responsible for the association of CHR11/17 with the SWR1 complex. MBD9, TRA1a, and TRA1b function as canonical components of the SWR1 complex to mediate H2A.Z deposition. CHR11/17 are not only responsible for nucleosome sliding but also involved in H2A.Z deposition. These results indicate that the association of the SWR1 complex with CHR11/17 may facilitate the coupling of H2A.Z deposition with nucleosome sliding, thereby co-regulating gene expression, development, and flowering time.