热冲击诱导沉默的核糖体,并重组mRNA周转率
Sayanur Rahaman1, Nicole Schiffelholz1, Nitish Mittal1
1Biozentrum, University of Basel, Spitalstrasse 41, 4056 Basel, Switzerland.
Cell reports
|October 18, 2025
概括
热应激会导致酵母细胞中更多的无声核糖体,这些核糖体未被翻译. 这种细胞适应通过重组信使RNA (mRNA) 周转率来优先考虑热冲击蛋白质的产生.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 压力反应应激反应
背景情况:
- 传递 RNA (mRNA) 被核糖体转化为蛋白质.
- 核糖体组合包括单核糖体 (单核糖体) 和多核糖体 (多核糖体).
- 热应激对mRNA循环和核糖体活性的影响尚未完全理解.
研究的目的:
- 为了研究热应激对mRNA-核糖体关联和酵母体核糖体状态的影响.
- 为了确定沉默的单体是否是一种对压力的一般细胞适应.
主要方法:
- 酵母细胞受到热冲击.
- 分析了mRNA与核糖体的关联以及核糖体组件的组成.
- 评估了单体体中转化启动因子和折叠蛋白的存在.
主要成果:
- 热应激显著增加了酵母细胞中单体的比例.
- 大多数热诱导的单体是无声的,缺乏相关的mRNA和关键的翻译/折叠蛋白.
- 在其他压力条件下也观察到沉默的单体,这表明了一般的适应机制.
- 热冲击减少了整体的mRNA-核糖体关联,但特别促进了热冲击蛋白转录的翻译.
- 对于热冲击蛋白质转录,mRNA半衰期没有延长.
结论:
- 热应激诱导沉默单体的显著增加作为细胞适应.
- 这种mRNA周转的重组优先考虑了热冲击蛋白质的合成.
- 沉默的单体体代表了在不同类型的压力中保存的应激反应机制.
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