通过DDM1结合的核细胞结构揭示了异色素重塑的机制
Hongwei Zhang1, Zhanxi Gu2, Yuan Zeng1
1Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.
Structure (London, England : 1993)
|June 13, 2024
概括
减少DNA甲基化1 (DDM1) 重塑染色质以使可转移元素沉默. 低温EM结构揭示了DDM1如何与核细胞相互作用,显示了DNA解和基因素尾部的接触,提供了对植物异染色素的洞察.
科学领域:
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 结构生物学 结构生物学
背景情况:
- SWI/SNF2染色体重塑器,降低DNA甲基化1 (DDM1),对于沉默可转移元素 (TE) 至关重要.
- DDM1在圣色和异色两种区域都起作用,保持基因组的稳定性.
- 了解DDM1的机制是理解植物中异性染色素调节的关键.
研究的目的:
- 为了确定近原子分辨率的冷电子显微镜 (cryo-EM) DDM1-核体复合物的结构.
- 阐明DDM1与含有标准素H2A和变体H2A.W.的核细胞相互作用的结构基础.
- 为了获得对DDM1-介导的色素重塑的机械洞察力.
主要方法:
- 电子显微镜 (cryo-EM) 用于确定复杂的结构.
- 生物化学下拉实验用于研究蛋白质相互作用.
- 在ADP-BeFx的存在下分析DDM1-核酶体复合体.
主要成果:
- 获得了DDM1-核H2A和DDM1-核H2A.W复合物的近原子分辨率的冷EM结构.
- 核体DNA的解封方式不同,取决于是否存在histon H2A或H2A.W.
- DDM1与核细胞和基因组H4 N-终端尾巴的一个DNA旋转相互作用.
- 拉下测试表明DDM1与基因素H2A.W.核心区域之间存在直接相互作用.
结论:
- DDM1与核细胞的相互作用涉及DNA解和基因素尾部结合.
- 素H2A.W的存在影响核细胞DNA结构和DDM1相互作用.
- 这些发现提供了对DDM1在植物异染色重塑中的作用的机制性见解.
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