动态改造由环酶关联蛋白和CAP-Abp1复合体对动素网络的改造
Siyang Guo1, Gregory J Hoeprich1, Joseph O Magliozzi1
1Department of Biology, Brandeis University, 415 South Street, Waltham, MA 02454, USA.
Current biology : CB
|October 5, 2023
概括
循环酶相关蛋白 (CAP) 和动氨酸结合蛋白1 (Abp1) 意外地捆绑和滑动动氨酸丝,促进网络紧缩. 这种保存的F-actin重塑活性增强了没有ATP的细胞组织.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 细胞骨动力学 细胞骨动力学
背景情况:
- 在体内,酸纤维的空间组织和重塑成更高阶网络的过程仍然不完全理解.
- 动因动态对于各种细胞过程至关重要,包括细胞形状,运动性和分裂.
研究的目的:
- 为了研究由环酶相关蛋白 (CAP) 驱动的意想不到的F-actin"凝聚"活性.
- 阐明1 (Abp1) 活性蛋白结合蛋白在增强CAP介导的活性蛋白重塑中的作用.
- 了解这种行为组织过程的分子机制和保存性质.
主要方法:
- 使用S. cerevisiae CAP和Abp1.1,直接观察了行为丝动态.
- 对CAP和Abp1.1的保存哺乳动物同类的分析.
- 研究结构-功能关系,包括CAP寡合化域和螺旋折叠域 (HFD) 的作用.
- 对遗传相互作用的评估和蛋白质缺失的表型分析.
主要成果:
- 观察到CAP和Abp1可以快速捆绑和滑动actin丝,最大限度地重叠并促进紧缩成捆绑.
- 这种F-actin凝聚活性不需要ATP,并且在不同物种中保持.
- 凝聚性取决于CAP的寡合化领域,需要CAP,Abp1和F-actin之间的相互作用.
- CAP的螺旋折叠域 (HFD) 不参与凝聚,使其与其切割/脱聚合功能区别开来.
结论:
- CAP表现出一种新的F-actin重塑功能,通过丝的滑动和捆绑促进捆绑紧缩.
- CAP和Abp1之间的相互作用显著增强了这种凝聚活动.
- 这些发现揭示了由CAP-Abp1相互作用驱动的actin网络组织的新机制,这对了解细胞结构和功能在体内有意义.
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