极性蛋白Par6通过与aPKC的动态相互作用促进Lgl的过程性酸化
Lior Almagor1,2, William I Weis3,4
1Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA. lalmagor@stanford.edu.
Communications biology
|July 2, 2025
概括
表皮细胞的极性取决于非典型的蛋白质激酶-C (aPKC) /Par6复合物化Lethal巨型幼虫 (Lgl) 蛋白质. 这项研究表明,Par6稳定了该复合体,使Lgl高效酸化和调节膜结合成为可能.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 表皮细胞的极性对于组织功能至关重要,并由顶-基底轴建立来调节.
- 非典型的蛋白激酶-C (aPKC) 和Par6复合体是细胞两极分化的关键调节者.
- aPKC/Par6酸化物 致死性巨 (Lgl) 蛋白质,防止顶峰膜结合并促进底侧局部化.
研究的目的:
- 阐明Lgl2与aPKCι/Par6复合体之间的相互作用的结构和机制基础.
- 了解Par6在促进aPKCι的Lgl2酸化中的作用.
- 提供对Lgl膜结合调节的结构性见解.
主要方法:
- 电子显微镜 (cryo-EM) 用于确定复杂的结构.
- 生物化学测试以表征蛋白质相互作用和酸化.
- 对三元复合体形成和稳定的分析.
主要成果:
- 帕尔6蛋白通过独特的多表面相互作用稳定一个三元的Lgl2/aPKCι/Par6复合体.
- Par6b诱导Lgl2的过程性酸化,从而产生多酸化的形式.
- 帕尔6b维持了Lgl2与aPKCι在激酶核酸结合状态中的接触,确保了高效的酸化.
结论:
- aPKC/Par6复合体为有效调节Lgl蛋白的膜结合提供了机制基础.
- 结构数据揭示了Par6如何促进Lgl酸化,这对上皮质极性至关重要.
- 这项工作增强了对保存极性复杂机制的理解.
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