蛋白质酶凝聚物形成是由与穿因子和K48连接的无处不在链的多价值相互作用驱动的
bioRxiv : the preprint server for biology
|July 10, 2023
概括
蛋白质酶凝聚物通过长的无处不在链和穿因子形成,在压力期间封存基质. 这种机制涉及特定的无素受体,揭示了储存之外的凝结物的功能.
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:
- 细胞压力可以诱导蛋白质体的重新定位到酵母和哺乳动物细胞中的特定凝聚物.
- 驱动蛋白酶体凝聚物形成的分子相互作用仍然不完全理解.
研究的目的:
- 阐明了酵母体中蛋白质酶凝聚物形成的分子机制.
- 确定参与这个过程的关键因素,包括泛素链和穿蛋白.
主要方法:
- 对具有穿因子基因缺失的酵母菌株 (Rad23,Dsk2,DDI1) 的分析.
- 调查K48连接的乌比奎链在凝结物形成中的作用.
- 在各种压力条件下,对内在蛋白质酶泛素受体 (Rpn1,Rpn10,Rpn13) 的表征.
主要成果:
- 在酵母体中形成蛋白质酶凝聚剂需要长的K48结合的泛素链和Rad23和Dsk2.2的穿因子.
- 删除DDI1导致构成性蛋白酶体凝聚物,与累积的无酸基质相关.
- 特定的蛋白质酶内在的基因素受体对于不同的凝结诱导条件至关重要,这表明功能多样性.
结论:
- 长的K48结合的泛素链作为支架,调解蛋白质酶凝聚体组合的多价值相互作用.
- 蛋白质酶凝结物将非活跃的蛋白质酶和无素基质隔离起来,可能是在能量耗尽的状态下.
- 这些发现揭示了蛋白质体凝结物具有超出简单存储的特定功能,由不同的分子组件调节.
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