TORC1通过Rag GTPase tether Tco8989自主控制其空间分区
Raffaele Nicastro1, Marie-Pierre Péli-Gulli1, Marco Caligaris1
1Department of Biology, University of Fribourg, Fribourg, Switzerland.
Cell reports
|May 13, 2025
概括
酵母利用Tco89将TORC1与Rag GTPases结合起来,调节Sch9激酶的活性. 通过酸化,TORC1稳定了Tco89,防止其降解,并维持TORC1的营养感应本地化.
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:
- 拉巴胺素复合体1 (TORC1) 的标是细胞生长和恒温的关键调节者.
- TORC1集成营养信号,特别是氨基酸的可用性,在内分泌系统.
- 在哺乳动物中,Rag GTPases通过猛禽子单元将TORC1招募到溶解体中,这是激活必不可少的过程.
研究的目的:
- 研究酵母TORC1被招募到活性Rag GTPases的机制.
- 在没有哺乳动物猛龙爪域的情况下,识别负责将TORC1与Rag GTPases结合的酵母骨科.
- 为了阐明TORC1如何调节其效应酶Sch9以响应氨基酸可用性.
主要方法:
- 在酵母 (Saccharomyces cerevisiae) 中进行基因分析.
- 酸化部位映射和蛋白质分解研究.
- 使用显微镜进行亚细胞局部化测试.
- 生物化学测试以评估酶活性.
主要成果:
- 酵母使用真菌特异性蛋白Tco89将TORC1绑定到活性Rag GTPases,与哺乳动物猛龙爪域不同.
- Tco89充当支架,使TORC1能够酸化和稳定自己,从而校准Sch9激酶活性.
- TORC1的失活导致Tco89蛋白解,导致TORC1从真空细胞再分配到信号内分泌体,并从Sch9.9空间分离.
结论:
- 酵母TORC1利用Tco89进行溶酶体招募,显示出一种保留但与哺乳动物不同的机制.
- TORC1动态控制Tco89的稳定性及其自身的亚细胞局部化,以适应营养的波动.
- 这种空间调节允许通过在营养物质稀缺时将TORC1与其效应器空间分开来节约能量.
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