洞察涉及全长KRAS野生类型和P环突变体激活机制的结构动态
Vinod Jani1, Uddhavesh Sonavane1, Rajendra Joshi1
1Centre for Development of Advanced Computing (C-DAC), Panchavati, Pashan, Pune, India.
Heliyon
|September 9, 2024
概括
酸盐结合环 (P-环) 中的KRAS突变破坏了正常的细胞功能. 这项研究揭示了P-循环突变如何全质地改变KRAS蛋白的动态,影响核酸结合和水解,这对于治疗设计至关重要.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 计算化学计算化学
背景情况:
- 克拉斯蛋白突变在各种癌症中很常见,特别是在12位,13位和61位.
- 酸盐结合区域 (P环) 的突变可以导致构成性活跃的KRAS蛋白,破坏细胞过程.
研究的目的:
- 为了研究KRAS突变 (G12D,G12V,G13D) 的结构灵活性和全效应,在GDP-bound (不活跃) 和GTP-bound (活跃) 状态中.
- 了解这些突变如何影响蛋白质动力学和核酸水解,以改善治疗策略.
主要方法:
- 在野生类型和突变KRAS结构 (GDP-bound和GTP-bound) 上进行了广泛的分子动力学模拟 (24μs).
- 动态交叉相关性分析和马尔科夫状态建模用于分析结构变化和结构灵活性.
主要成果:
- 在P循环中的局部突变通过键和疏水网络对遥远的蛋白质区域产生全质影响.
- 突变改变了与GDP/GTP的相互作用,通过影响SW-I,SW-II等区域以及前面的α3.3循环来影响核酸水解.
- 特别是G13D突变增加了结构刚性,限制了形状状态.
结论:
- 该研究确定了先于α3螺旋和α3螺旋本身的循环在调节核酸水解方面至关重要,与SW-I和SW-II.
- 这些发现为KRAS驱动的癌症提供了洞察力,并为药物设计提供了潜在的治疗点.
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