通过分离酶降低PP2A(Cdc55) 酸酶的调节,可以启动发芽酵母中的线粒性退出
Ethel Queralt1, Chris Lehane, Bela Novak
1Chromosome Segregation Laboratory, Cancer Research UK London Research Institute, Lincoln's Inn Fields Laboratories, 44 Lincoln's Inn Fields, London WC2A 3PX, United Kingdom.
Cell
|May 23, 2006
概括
在酶中分离酶的激活降低了酸酶的调节,使得循环素依赖激酶 (Cdk) 能够化Net1并释放Cdc14酸酶,从而促进发芽酵母中的线粒退出.
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:
- 线粒体环林依赖激酶 (Cdk) 的活性必须下降才能退出线粒体分裂.
- 在芽的酵母中,Cdc14酸酶的激活对于线粒体的退出至关重要.
- 在核中,Cdc14被Net1抑制,直到发生相.
研究的目的:
- 为了阐明Net1酸化在异相期间的机制.
- 了解Cdk活动下降时Cdc14是如何被激活的.
- 为了呈现一个定量模型的芽酵母中线粒退出.
主要方法:
- 研究了分离酶,PP2A(Cdc55) 和Net1.1.之间的蛋白质与蛋白质相互作用.
- 作为一个模型生物体,利用了芽酵母 (S. cerevisiae).
- 开发了线粒体退出的定量模型.
主要成果:
- PP2A(Cdc55) 酸酶在转化阶段保持Net1在低酸化状态.
- 酶激活分离酶降低了PP2A的调节.
- 分离酶介导的PP2A ((Cdc55) 下调促进了Cdk依赖的Net1酸化和Bfa1酸化,激活了线粒体退出网络.
结论:
- PP2A的分离酶依赖抑制 (Cdc55) 是启动Net1酸化和随后的Cdc14释放的关键步骤.
- 这种机制确保了 mitotic 及时退出,即使 Cdk 活动减少.
- 这些发现为了解细胞循环调节和线粒细胞进展提供了新的框架.
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