寒冷诱导的核细胞体动态与Arabidopsis FLC的沉默有关
Miguel Montez1, Danling Zhu1,2, Jan Huertas3,4
1John Innes Centre, Norwich Research Park, Norwich, United Kingdom.
Nature communications
|July 2, 2025
概括
长时间暴露在寒冷中会改变植物染色质结构,抑制花C基因. 这种取决于温度的表观遗传开关涉及核酶体动态的变化,并且部分由VERNALIZATION1调节.
科学领域:
- 植物分子生物学 植物分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 染色体的调节 染色体调节
背景情况:
- 温度是一个关键的环境因素,通过表观遗传机制影响基因表达.
- 长时间暴露于寒冷会导致Arabidopsis中FLOWERING LOCUS C (FLC) 基因的表观遗传沉默,这是开花时间的关键调节者.
- 核动力学和染色质结构是调节基因可访问性和转录的核心.
研究的目的:
- 为了研究FLC基因的局部染色体结构的温度依赖转变.
- 阐明核酶体动力学在冷诱导表观遗传沉默中的作用.
- 为了确定VERNALIZATION1 (VRN1) 在这种对温度敏感的染色质重塑过程中的参与.
主要方法:
- 使用高分辨率技术进行体内染色质测量.
- 在近原子分辨率的粗粒度分子模拟.
- 对基因组修饰 (H3K27me3,H2Aub) 和基因组变异 (H2A.Z) 的分析.
主要成果:
- 在FLC转录起点 (TSS) 的染色质结构中观察到温度依赖的过渡,从转录活性转移到沉默状态.
- 暴露于寒冷会降低核细胞组的动态,并重新放置+1核细胞组,从而导致FLC的转录抑制.
- VERNALIZATION1 (VRN1) 蛋白部分调解这种染色体过渡; 缺少它会导致H2A.Z增加,核细胞更为动态,以及H2Aub和H3K27me3积累受损.
结论:
- 局部核酶体动力学对于将温度信号整合到表观遗传切换机制中至关重要.
- 温度引起的染色质结构变化,特别是核细胞的定位和动态,调节FLC基因表达以应对寒冷.
- VRN1通过影响核酶体动力学和基因组修饰来建立沉默的染色质状态.
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