玉米pl1位点的参突变与远距离并列重复中的RdDM活性有关
Natalie C Deans1,2, Joy-El R B Talbot1,3, Mowei Li1,2
1Department of Molecular Genetics, The Ohio State University, Columbus, Ohio, United States of America.
PLoS genetics
|May 30, 2024
概括
玉米基因突变是门德尔遗传的一个例外,与小RNA生产和DNA甲基化有关. 这种表观遗传机制涉及染色体上的特定重复区域,调节基因转录.
科学领域:
- 遗传学 遗传学 是一个
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 植物生物学 植物生物学
背景情况:
- 门德尔遗传的例外情况,比如玉米中的转基因突变,表明了新的染色体行为.
- 在玉米中的基因突变背后的特定染色体特征仍然在很大程度上是未知的.
- 玉米中的Pl1-Rhoades等位基因表现出对突变,影响植物色素.
研究的目的:
- 为了研究染色体特征和分子机制,负责玉米的转基因变异.
- 确定小RNA生产和DNA甲基化在Pl1-Rhoades基因遗传抑制中的作用.
主要方法:
- 分析与RNA聚合酶IV功能相关的小RNA生产.
- 调查不同pl1单元型中的双重重复副本数量的变化.
- 使用4C相互作用,CHD3a-依赖的小RNA分析,核酶敏感性和多基化RNA分析.
- 进行比较和突变分析,以将转录抑制与分子标记者相关联.
主要成果:
- 小型RNA的产生,反映了RNA聚合酶IV活动的同时重复,与Pl1-Rhoades. meiotically-heritable抑制相吻合.
- 通过跨同类沉默特征的参数变异,在有三个重复单元但没有两个的pl1单元类型中观察到.
- 一个特定的重复子区域显示了调节潜力,由4C相互作用,小RNA配置文件和核酶敏感性表明.
- 对Pl1-Rhoades的转录抑制与该亚区域的24核酸RNA产生和细胞因子甲基化相关.
结论:
- 玉米中的转基因突变涉及RNA导向的DNA甲基化,该甲基化作用于一个依赖拷贝数的转录调节元件.
- 这些发现支持一种模型,其中通过小RNA和DNA甲基化进行表观遗传调节是基因变异的基础.
- 特定的重复结构及其相关的表观遗传修饰对于以遗传方式调节基因表达至关重要.
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