DNA损伤反应和RNA聚合酶II调节器Def1在细胞质中具有转录后功能
bioRxiv : the preprint server for biology
|October 28, 2024
概括
酵母Def1蛋白,以DNA损伤反应而闻名,也通过链接翻译和衰变来控制mRNA水平. 这一发现揭示了Def1作为转录,翻译和mRNA衰变中的基因表达的主调节者.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 细胞应激反应的应激反应
背景情况:
- Def1 (DNA损伤反应元素1) 是一种酵母蛋白,在压力期间参与RNA聚合酶II降解和转录.
- 虽然已知Def1在DNA损伤中的核作用,但其细胞质功能仍然未被描述.
- 这项研究调查了Def1在基因表达调节中的前所未知的细胞质作用.
研究的目的:
- 为了确定酵母Def1蛋白的新型细胞质功能.
- 阐明Def1在转录后基因调节中的作用,包括mRNA转化和衰变.
- 了解Def1与核糖体相互作用的分子机制及其对基因表达的影响.
主要方法:
- 近距离标记 (BioID) 用于识别细胞质中的Def1相互作用蛋白.
- 基因删除研究 (ΔDEF1) 评估对mRNA合成和衰变速率的影响.
- 报告员mRNA测定和蛋白质相互作用研究,以证实Def1的调节作用.
主要成果:
- Def1 与参与mRNA转录后控制和翻译的蛋白质相互作用.
- 删除DEF1导致mRNA合成和衰变的减少,表明转录缓冲.
- Def1通过其N端的泛素结合域与多核糖体结合,需要通过Not4.4进行eS7a泛素化.
- Def1的C端与翻译和衰变因子相互作用,作为链接翻译与mRNA衰变的支架.
结论:
- 除了其已知的核作用外,Def1还作为mRNA翻译和衰变的细胞质调节器.
- Def1 作为一种依赖于全方位素的支架,将核糖体相关的翻译状态与mRNA衰变途径连接起来.
- Def1被确立为基因表达的主调节者,影响转录,mRNA衰变和翻译.
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