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大壁-内硫素-PP2A/B55通路通过增强长长器调节的转录的翻译来调节进入静止状态
Javier Encinar Del Dedo1, M Belén Suárez2,3, Rafael López-San Segundo4
1Instituto de Biología Funcional y Genómica, CSIC, University of Salamanca, 37007, Salamanca, Spain. jedel_dedo@usal.es.
Nature communications
|December 5, 2024
概括
进入静止状态的细胞使用Greatwall-Endosulfine-PPA/B55通路将TORC1无活化与TORC2激活联系起来. 这提高了特定mRNA的翻译效率,在压力期间支持蛋白质平衡.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 静止细胞需要持续的蛋白质合成来实现平衡.
- 压力通过TORC1无活化和TORC2激活触发了裂变酵母静止.
研究的目的:
- 为了阐明连接TORC1下调和TORC2上调在静止进入过程中的通路.
- 调查这个途径在维持翻译计划中的作用.
主要方法:
- 在裂变酵母中研究了大壁-内硫酸-PPA/B55通路.
- 分析了依赖延长器的tRNA修改.
- 检查了mRNA的翻译效率和密码体的使用.
主要成果:
- 证明了大墙-内硫-PPA/B55路径链接TORC1和TORC2信号.
- 显示了依赖延长器的tRNA修饰的激活 (U34,A37).
- 鉴定了AAA与AAG氨酸密码子丰富的mRNA的增强翻译,包括关键调节蛋白.
结论:
- 提出了一种应激反应的机制,涉及tRNA表写体和子偏差.
- 突出了翻译调节在维持静止期间细胞功能中的作用.
- 强调了tRNA修饰和用于蛋白质平衡的编码子使用之间的协调相互作用.
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