一个域互换的CaMKII构造促进了链接介导的全调节
Bao V Nguyen1,2,3, Can Özden1,3, Kairong Dong1,4
1Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA 01003, USA.
bioRxiv : the preprint server for biology
|April 8, 2024
概括
信号传递对记忆和心脏功能至关重要. /卡尔莫杜林依赖蛋白激酶II (CaMKII) 变体调节这种信号传递,链接区域的电荷控制Ca2+/CaM灵敏度和全酶结构.
科学领域:
- 生物化学和分子生物学
- 细胞信号传输 细胞信号传输
- 结构生物学 结构生物学
背景情况:
- (Ca2+) 信号传递对于重要的生理过程至关重要,包括记忆形成和心脏功能.
- /卡尔莫杜林依赖蛋白激酶II (CaMKII) 是一种关键的酶,可以调解细胞对Ca2+的反应.
- 哺乳动物CaMKII存在于四个类型中,通过替代拼接产生了70多种变体,它们的链接区域不同.
研究的目的:
- 系统地研究可变链接区域在调节CaMKII活性和Ca2+/calmodulin敏感性的作用.
- 阐明CaMKII监管的结构基础,特别是域互换和链接器相互作用的影响.
主要方法:
- 进行X射线晶体学以确定全长CaMKIIδ.δ的结构.
- 位点定向的突变发生,以探测CaMKII全酶内的特定接口的功能.
- 分子动力学模拟和小角度X射线散射 (SAXS) 来分析形状动力学和全酶结构.
主要成果:
- 一个X射线晶体结构揭示了一个域交换的构造在十二体CaMKIIδ全酶,与酶域与相邻子单元的枢纽域相互作用.
- 破坏枢纽-枢纽接口的突变导致了酶-枢纽相互作用的解离,改变了全酶固态度和Ca2+/CaM灵敏度.
- 域互换配置促进链接器-模素结合域相互作用,其中带电的残留物以异质调节CaMKII对Ca2+/CaM的敏感性.
结论:
- 在CaMKII链接区域内残留物的位置和电荷显著调节Ca2+/CaM灵敏度.
- 一个域互换的构造在CaMKII全酶结构和调节中起作用.
- 这项研究提供了一个新的结构和机制框架,以了解CaMKII全调节通过其可变链接区域.
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