单体缓冲转化应激,以允许活性核糖体延长
Rico Schieweck1, Giuliana Ciccopiedi1, Kenneth Klau1
1Biomedical Center (BMC), Department for Cell Biology and Anatomy, Medical Faculty, Ludwig-Maximilians-University, Munich, Germany.
Frontiers in molecular biosciences
|June 12, 2023
概括
细胞压力通过改变核糖体动力学来影响蛋白质合成. 在压力期间,单体活性优先受到影响,允许足够的翻译延长和细胞存活.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生化学
背景情况:
- 蛋白质合成对细胞功能至关重要,由核糖体活动调节.
- 核糖体在单体和多体之间循环,影响转化速率.
- 在细胞应激过程中单体和多体的平衡尚未得到充分理解.
研究的目的:
- 在转化应激下研究单体和多体的平衡和动力学.
- 了解细胞如何在压力条件下适应蛋白质合成.
主要方法:
- 使用定时的核糖体流失试验.
- 采用多体形分析来分析核糖体分布.
- 应用的转化应激条件:mTOR抑制,eEF2下调和氨基酸耗尽.
主要成果:
- 不同的转化应激因素对蛋白质合成产生了不同的影响.
- 所有测试的压力因素都优先影响单体活动.
- 即使在严重的氨基酸饥饿下,也检测到活跃的多元体,与不活跃的单元体.
- 细胞适应单体水平,在压力时有利于翻译延长.
结论:
- 在压力下,单体和多体水平是动态平衡的.
- 细胞表现出翻译性可塑性,以确保蛋白质合成的生存和恢复.
- 单体活动的适应对于在压力下保持翻译至关重要.
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