与核糖体相关的复合体调节了在线粒蛋白诱导的压力时的细胞转化
Jiaxin Qian1, Annika Nutz2, Katja Hansen2
1Interfaculty Institute of Biochemistry, University of Tübingen, Germany.
The FEBS journal
|December 8, 2025
概括
缺乏Tom70蛋白质的酵母细胞表现出线粒体缺陷和缓慢生长. 删除ZUO1,一个与核糖体相关的复杂伴侣,通过调节线粒体应激期间的蛋白质合成来预防这些问题.
科学领域:
- 细胞生物学 细胞生物学
- 线粒体生物学 线粒体生物学
- 分子生物学分子生物学
背景情况:
- 线粒体生物发生需要通过像Tom70.0.这样的受体输入细胞质蛋白质.
- 线粒体进口缺陷引发压力反应,包括减少蛋白质合成.
- 线粒体功能和细胞转化之间的联系尚未完全理解.
研究的目的:
- 研究Tom70对应物 (TOM70,TOM71) 在酵母线粒体生物发生中的作用.
- 阐明将线粒体功能障碍与细胞质转化率联系起来的分子机制.
- 在线粒体压力期间确定调节蛋白质合成的因素.
主要方法:
- 酵母遗传学:产生tom70Δ/tom71Δ和zuo1Δ突变的基因.
- 表型分析:细胞生长,线粒体生物发生试验.
- 分子分析:在压力条件下评估蛋白质合成速度.
主要成果:
- 删除TOM70和TOM71导致线粒体缺陷和酵母菌的缓慢生长.
- 删除ZUO1,一个与核糖体关联复合体 (RAC) 伴侣,在热应激下拯救了tom70Δ/tom71Δ突变体的缓慢生长和翻译缺陷.
- ZUO1删除加剧了线粒体缺陷,表明它在翻译调节中的特定作用.
结论:
- 在线粒体功能障碍期间,Zuo1对抑制蛋白质合成的信号通路至关重要.
- 核糖体关联复合体 (RAC) 作为压力控制的细胞转化调节剂.
- 一个新的范式表明,RAC介导了线粒体健康和蛋白质合成之间的交叉通话.
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