蛋白质稳定网络的特定分支调节与错误翻译相关的毒性
Donovan W McDonald1, Rebecca N Dib2, Christopher De Luca2
1Department of Biology, The University of Western Ontario, London, ONN6A 3K7, Canada.
Nucleic acids research
|May 16, 2025
概括
错误翻译转移RNA (tRNA) 变体对细胞健康有不同的影响. 特定的tRNA错误通过不同的机制破坏蛋白质折叠和降解途径,影响蛋白质静止.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 细胞生物学 细胞生物学
背景情况:
- 精确的蛋白质生物合成对于所有细胞功能至关重要.
- 人类基因组含有转移RNA (tRNA) 基因变异,导致氨基酸错误整合 (错误翻译).
- 错误翻译会对蛋白质静止产生负面影响,导致蛋白质错误折叠,以及蛋白质的合成和降解受损.
研究的目的:
- 研究特定的错误翻译tRNA变体如何与蛋白质稳定路径相互作用.
- 用Saccharomyces cerevisiae定量分析不同错误翻译tRNA对细胞健康和蛋白质平衡的影响.
主要方法:
- 用了Saccharomyces cerevisiae (芽芽酵母) 作为定量分析的模型生物.
- 测试了两种错误翻译tRNA Ser变体:proline到serine (P>S) 和 arginine到serine (R>S) 的错误整合.
- 评估了细胞适应性,蛋白质错折和蛋白质稳定路径相互作用.
主要成果:
- P>S错误整合损害了细胞适应性,并增加了对蛋白质错误折叠的敏感性超过R>S.
- 这两种tRNA变异都导致了血清错误融合,但通过不同的机制影响了蛋白质积累.
- R>S错误整合减少了Hsp70与错误折叠的蛋白质的关联;P>S损害了新生的多降解.
结论:
- 不同的错误翻译tRNA变体独特地破坏了特定的蛋白质稳定分支.
- 通过错误翻译tRNAs而导致蛋白质稳定性损害的独特机制损害了细胞健康.
- 了解这些机制对于理解遗传变异对细胞健康的影响至关重要.
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