异位增强剂-增强剂相互作用作为驱动基因调节区域中RNA导向DNA甲基化的因果作用
Yazhou Yang1, Jia Liu2, Stacy D Singer3
1College of Horticulture, Northwest A&F University, Yangling, China.
Plant biotechnology journal
|July 18, 2024
概括
转基因 cis-调节元件 (CREs) 可以通过非编码RNA (ncRNA) 和小干扰RNA (siRNA) 沉默基因,触发RNA指导的DNA甲基化 (RdDM). 在植物中,CRE-CRE相互作用驱动了这种表观遗传沉默.
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.
- 基因调节 基因调节
背景情况:
- 控制基因表达,影响表型和进化.
- 转基因CREs,特别是双重重复的CREs,通常会经历转录沉默.
- 非编码RNAs (ncRNAs) 和小干扰RNAs (siRNAs) 都与基因沉默机制有关.
研究的目的:
- 研究转基因CREs中转录沉默的机制.
- 确定ncRNAs,siRNAs和RNA导向DNA甲基化 (RdDM) 在这种沉默中的作用.
- 探索增强剂-增强剂相互作用对CRE活性和表观遗传修饰的影响.
主要方法:
- 为转基因分析选择了六种鲜花特有的CREs.
- 分析了ncRNA转录,siRNA生产和DNA甲基化.
- 使用了像CaMV35S增强剂 (35Se) 和AGAMOUS增强剂 (AGe) 这样的增强剂元素.
- 进行了基因组插入实验,研究增强剂-CRE相互作用.
主要成果:
- 在6个测试的CREs中,有3个在转基因环境中表现出沉默.
- 沉默是由ncRNAs通过处理成24-nt siRNAs来调节的,从而诱导RdDM.
- 该CaMV35S增强剂 (35Se) 增强了AGAMOUS增强剂 (AGe) 的异常ncRNA转录.
- 在AGe附近35Se的基因组插入诱导了ncRNA/siRNA的产生,新的甲基化和花突变.
结论:
- 由35Se和AGe示例的CRE-CRE相互作用可以在转基因和基因组状态中诱导RdDM.
- 这突显了植物中CRE-CRE相互作用的新型表观遗传作用.
- 这些发现解释了由于CRE相互作用而导致的转基因,重复基因和转基因中的超甲基化.
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