揭示机械激活:GAIN域在粘附中的展开和解离 GPCRs
Chaoyu Fu1,2, Wenmao Huang1,2, Qingnan Tang1
1Department of Physics, National University of Singapore, Singapore 117551, Singapore.
Nano letters
|October 13, 2023
概括
机械力量破坏了粘附G蛋白结合受体 (aGPCR) GAIN域的稳定. 这种脱离对于机械敏感激活至关重要,发生在细胞迁移期间的生理力水平.
科学领域:
- 生物物理学的生物物理.
- 细胞生物学 细胞生物学
- 结构生物学 结构生物学
背景情况:
- 粘附G蛋白合受体 (aGPCRs) 具有具有具有GPCR自蛋白解酶诱导 (GAIN) 域的细胞外区域 (ECRs).
- GAIN域有助于ECR自分裂成N端和C端碎片,但其机械性能尚不清楚.
研究的目的:
- 研究aGPCRs中GAIN域的机械稳定性和力诱导的构造变化.
- 确定机械力在GAIN域功能和aGPCR激活中的作用.
主要方法:
- 原子力显微镜 (AFM) 用于将受控的机械力 (1 pN/s负载率) 应用于选择的aGPCRs的GAIN域.
- 分析GAIN域的展开和解脱,以应对施加的力.
主要成果:
- 几个皮科纽顿的力量会破坏GAIN域的稳定.
- 在自剪切的aGPCR中,在部分展开后,GAIN域脱离Stachel序列发生.
- 不能切割的aGPCR和突变体表现出GAIN域的复杂机械展开.
- 在细胞迁移期间观察到GAIN域脱离.
结论:
- 获得域结构对生理力范围敏感.
- 机械力量在GAIN域脱离和aGPCR激活中发挥着关键作用,支持机械激活假设.
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