PYM1以基因架构依赖的方式限制非正规的外结复合体占用,以调整mRNA表达
Manu Sanjeev1,2, Lauren A Woodward1, Michael L Schiff3
1Department of Molecular Genetics, The Ohio State University, Columbus, OH, 43210, USA.
Nature communications
|August 30, 2025
概括
埃克森结合复合体 (EJC) 拆解因子PYM1使EJC独立于翻译而变得不稳定. PYM1 限制非正规的 EJC,这是一个由黄病毒劫持的功能,以改变宿主 mRNA 的调节.
科学领域:
- 分子生物学
- 核糖核酸生物学
- 病毒学
背景情况:
- 在RNA拼接过程中,exon连接复合体 (EJC) 在exon-exon连接处沉积.
- 在mRNA代谢中发挥关键作用,包括拼接,输出,转化和衰变.
- 虽然EJC的拆解与翻译有关,但相关因素尚未得到充分理解.
研究的目的:
- 调查PYM1在EJC监管中的作用.
- 确定EJC-PYM1相互作用的机制.
- 探索PYM1对非正规EJC定位和功能的影响.
主要方法:
- 在人类胚胎细胞293 (HEK293) 中进行了实验.
- 研究了EJC-PYM1相互作用及其在EJC破坏中的作用.
- 分析了不同内核数量的EJC本地化.
- 研究了PYM1抑制对mRNA稳定性和局部化的影响.
主要成果:
- EJC-PYM1相互作用对于翻译独立的EJC不稳定是必不可少的.
- 缺少PYM1的EJC会在非正规位点的内核贫富转录上积累.
- 非正规的EJC可以触发无意义介导的mRNA衰变.
- 抑制PYM1会稳定特定的mRNA,并改变它们的局部化到TIS颗粒.
- 弗拉维病毒囊蛋白与PYM1的相互作用模仿了PYM1的抑制作用.
结论:
- 通过限制非正规的EJC结合,PYM1作为EJC特异性因素.
- PYM1的功能对于适当的mRNA命运调节至关重要.
- 弗拉维病毒利用PYM1来操纵宿主mRNA的调节,使其受益.
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