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通过CDC48 ((UFD1/NPL4) 调动经过处理的,与膜结合的SPT23转录因子,这是一个对无处不在素有选择性的伴侣
1Department of Molecular Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18a, 82152, Martinsried, Germany.
Cell
|December 6, 2001
概括
酵母OLE通路使用转录因子SPT23,由受调节的无素/蛋白酶依赖处理 (RUP) 激活,以控制膜流动性. CDC48 ((UFD1/NPL4) 复合体选择性地释放了经过处理的SPT23 (p90) 用于核准.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 酵母中的OLE通路通过控制与ER结合的酶Delta9-脂肪酸脱酶 (OLE1) 来调节膜流动性.
- SPT23是一种转录因子,也是哺乳动物NF-kappaB的同类物,是该途径的关键调节者.
- SPT23存在于固定在ER膜上的非活性前体,需要受调节的无素/蛋白质酶依赖处理 (RUP) 来激活.
研究的目的:
- 阐明SPT23激活的机制及其后续处理和核准.
- 为了研究蛋白质复合体动力学和在SPT23调控中的无处不在的作用.
- 描述CDC48 ((UFD1/NPL4) 综合体在加工无化蛋白质基质中的功能.
主要方法:
- 分析SPT23的二分化和加工.
- 在激活过程中调查SPT23无化状态.
- 生物化学试验研究了SPT23,其加工形式 (p90) 和CDC48 ((UFD1/NPL4) 复合体之间的相互作用.
主要成果:
- 在接受受调节的无素/蛋白质酶依赖加工 (RUP) 之前,SPT23是二元化的.
- 经过加工的形式,p90,最初仍然通过ubiquitin修饰与未经加工的SPT23前体结合.
- 伴侣类的CDC48 ((UFD1/NPL4) 复合物选择性地从其核转移伙伴中释放p90,表明它更喜欢无处不在的基质.
结论:
- SPT23激活涉及二分化和顺序处理步骤.
- 乌比奎丁修饰在将加工的SPT23 (p90) 与其前体结合起着至关重要的作用.
- CDC48 ((UFD1/NPL4) 复合体作为选择性释放无素SPT23的关键因素,突出其在无素依赖蛋白质加工中的作用.
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