转基因基因和原生基因的整个编码区域之间的连续身份,而不是特殊区域,对于强大的共同抑制是必不可少的
Yangyang Chen1, Shijie Ma2, Hangkai Ku1
1College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China.
概括
植物中的基因沉默,称为共抑制,需要在整个编码区域之间连续的序列标识才能触发. 这项研究表明,特定区域或siRNA峰值对于这种基因沉默机制来说并不必不可少.
科学领域:
- 植物分子生物学 植物分子生物学
- 基因沉默机制的基因抑制机制
- 在RNA干扰过程中,RNA干扰
背景情况:
- 同抑制是植物中关键的基因沉默机制,对于理解基因调节至关重要.
- 同抑制的确切触发因素仍然难以捉摸,阻碍了进一步的研究.
研究的目的:
- 为了研究植物共抑制的触发机制.
- 确定序列标识和特定区域在联合抑制效率中的作用.
主要方法:
- 利用强大的共同抑制系统对脂肪酸脱酶2 (FAD2) 和脂肪酸延长酶1 (FAE1) 基因.
- 在转基因系中分析了小干扰RNA (siRNA).
- 构建并测试了混合基因与交换的5'和3'部分.
- 根据不同程度的连续序列相同性评估共抑制频率.
主要成果:
- siRNAs分布在整个FAD2编码区域,但峰值部位的突变并没有缓解共抑制.
- 一个具有同义突变的合成FAD2基因未能诱导共抑制.
- 混合基因和不同的序列身份证实了连续身份对于强大的共同抑制的重要性.
结论:
- 在整个编码区域内连续的序列标识对于强大的共抑制至关重要.
- 特定区域或siRNA积累峰值不是共抑制的主要触发因素.
- 这一发现澄清了植物基因沉默背后的机制.
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