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通过整合素αI域进行分子抽取
Jeremy A Hollis1,2, Matthew C Chan1, Harmit S Malik1,3
1Division of Basic Sciences, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA.
Science advances
|September 10, 2025
概括
整体蛋白中的I域是从一个原结合域进化而来的,使得结合并保持功能,尽管阻断了祖先的口袋. 这种分子捕获扩大了脊椎动物的细胞通信.
科学领域:
- 生物化学 生物化学
- 进化生物学 进化生物学
- 结构生物学 结构生物学
背景情况:
- 整合素是细胞表面受体,对细胞粘附和信号传递至关重要.
- 干结合会诱导信号传输的整合素的形状变化.
- 整合素α子单元的插入 (I) 域的演变对传统的激活机制提出了挑战.
研究的目的:
- 为了阐明整合素中的I域如何保留功能,尽管阻碍了祖先的联结体结合口袋.
- 研究I域介导的整合蛋白激活的进化起源和机制.
- 了解I域在扩大脊椎动物细胞通信中的作用.
主要方法:
- 对αEβ7和α4β7整合素的冷电子显微镜结构进行比较分析.
- 对两种整蛋白类型的阿波和带结合状态的确定.
- 追踪I域的进化历史.
主要成果:
- I 域本质上模仿一个外部连接体来维持整合素激活.
- I 域的起源可以追溯到一个祖先的原蛋白-原蛋白相互作用域.
- 这种古老的分子抽取允许在I域插入时立即激活整合素.
结论:
- I域的演变代表了整合函数的一个关键适应.
- 一个原结合域的分子抽取促进了整合素激活和扩展信号传递.
- 这些发现为脊椎动物细胞通信的进化和生化基础提供了洞察力.
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