由饥饿诱导的抑制剂Rts3抑制Sit4/PP6在TORC1下游的门静止
Ladislav Dokládal1, Marie-Pierre Péli-Gulli1, Josephine Alba1,2
1Department of Biology, University of Fribourg, Fribourg, Switzerland.
Nature communications
|February 26, 2026
概括
研究人员发现了Rts3,这是一种对Sit4酸酶起到制动作用的蛋白质,控制细胞静止深度和生存的可逆性. 这一发现揭示了一个新的反循环,调节细胞生存机制.
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:
- 细胞静止对于在营养稀缺期间的生存至关重要.
- 控制静止深度和可逆性的机制尚未完全理解.
研究的目的:
- 确定Saccharomyces cerevisiae中TORC1下游静止轨迹的调节者.
- 描述Rts3在调节酸酶活性和细胞反应中的作用.
主要方法:
- 利用酸酶抑制剂珠和质谱测量来识别Rts3作为酸酶相互作用体.
- 使用结构分析研究了Rts3与PP6酸酶Sit4的相互作用.
- 研究了TORC1对Rts3的调节及其降解途径.
主要成果:
- 确定Rts3作为Sit4-Sap185/190酸酶复合物的抑制剂.
- 证明Rts3的α螺旋介质直接与Sit4催化裂结合.
- 显示的Rts3在饥饿期间被转录诱导,并在通过TORC1依赖的途径通过营养补充后迅速降解.
- 揭示Rts3限制Sit4活动,调节反应通路并防止目标积累.
结论:
- 在Sit4上,Rts3充当动态分子制动器,微调静止深度.
- 这种调节确保了保护性但可逆的静止状态,增强了长期生存.
- Rts3-Sit4轴表示一个关键的反循环关闭静止.
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