一种新型的蛋白质激酶同类物,对于蛋白质分类至酵母溶解体类真空分子至关重要
P K Herman1, J H Stack, J A DeModena
1Division of Biology, California Institute of Technology, Pasadena 91125.
Cell
|January 25, 1991
概括
Vps15蛋白激酶对于将酶导向酵母真空细胞至关重要. 影响其激酶活性的突变破坏了这一过程,表明酸化调节了蛋白质分类.
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:
- 酵母真空体对于细胞过程至关重要.
- 能有效地将酸酶输送到真空层至关重要.
- 特定蛋白质激酶在真空蛋白质分类中的作用尚未完全理解.
研究的目的:
- 为了研究VPS15基因及其编码蛋白的功能,Vps15p.
- 为了确定Vps15p激酶活性在蛋白质分类中对酵母真空细胞的作用.
- 阐明Vps15p调解真空蛋白传递的机制.
主要方法:
- 在Vps15p激酶域的位点定向突变发生.
- 对突变菌株中真空酸酶分泌的分析.
- 在体内酸化试验.
- 亚细胞分离和生物化学关联研究.
主要成果:
- 在Vps15p激酶域中的点突变导致真空蛋白酶的分泌.
- 在体内对Vps15p的酸化在激酶域突变中受损.
- Vps15p与Golgi晚期或囊泡区外围相关.
- Vps15p包含一个共识的myristoylation信号,表明脂质修饰.
结论:
- Vps15p激酶活性对于高效的真空蛋白质分类至关重要.
- 由Vps15p介导的蛋白质酸化可能起到细胞内运输中的调节开关作用.
- Vps15p可能在戈尔吉或在囊泡介导的传输到真空管中发挥作用.
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