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通过受调节的无素/蛋白酶依赖性处理激活膜结合的转录因子
T Hoppe1, K Matuschewski, M Rape
1Department of Molecular Cell Biology, Max Planck Institute for Biochemistry, Martinsried, Germany.
Cell
|September 28, 2000
概括
两个酵母蛋白,SPT23和MGA2,是通过无素/蛋白酶处理激活的,而不是通过膜内蛋白解. 这种新的途径表明脂肪酸池调节了膜蛋白激活.
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:
- 集成膜蛋白处理对于细胞功能至关重要,如固醇调节和信号传递.
- 调节性内膜蛋白解 (RIP) 是处理这些蛋白质的既定机制.
- 其中的例子包括Notch信号,未折叠的蛋白质反应和阿尔茨海默病中的APP处理.
研究的目的:
- 研究酵母转录因子SPT23和MGA2.2的激活机制.
- 为了确定SPT23和MGA2是否使用RIP或替代处理途径.
- 了解SPT23和MGA2在调节细胞过程中的作用以及它们与膜组成的潜在联系.
主要方法:
- 在酵母中分析SPT23和MGA2加工.
- 调查在SPT23和MGA2激活中泛素/蛋白酶体系统的作用.
- 通过脂肪酸池评估SPT23加工的监管.
主要成果:
- SPT23和MGA2被合成为局部存在于ER/核膜的非活性前体.
- 激活是通过依赖于全方位素/蛋白质酶的处理发生的,与RIP不同.
- 蛋白质酶依赖的SPT23处理是由细胞脂肪酸水平调节的.
结论:
- SPT23和MGA2激活是一种新的,非RIP机制,用于处理膜蛋白.
- 这一途径突出显示了乌比奎丁/蛋白酶体系统在调节转录因子中的参与.
- 脂肪酸池可以作为膜组成的传感器,影响SPT23激活.
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