蛋白质两极化对于稳定AF-2和helix-2'域在PPAR-gamma的联体结合中至关重要
1Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
Journal of the American Chemical Society
|November 15, 2008
概括
蛋白质两极化对于稳定过氧体增殖器激活受体 (PPAR-) 和其与罗西格利塔等激动剂的结合至关重要. 这项研究强调了两极化如何保留必要的键和蛋白质结构,这对生物功能至关重要.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 计算化学计算化学
背景情况:
- 过氧体增殖器激活受体玛 (PPAR-玛) 是一个关键的转录因子,调节脂肪细胞分化和葡萄糖稳态.
- 对PPAR-gamma的联体结合会影响其转录活性和结构构造.
研究的目的:
- 通过分子动力学 (MD) 模拟来研究蛋白质两极化在PPAR-gamma连接体结合的动态中的作用.
- 为了比较极化和非极化力场对PPAR-gamma-rosiglitazone复合物的稳定性和结构的影响.
主要方法:
- 对PPAR-gamma进行了分子动力学 (MD) 模拟.
- 模拟利用两极化和非极化力场来模拟与激动剂罗西格利塔的相互作用.
- 分析的重点是键稳定性,二次结构保存 (特别是螺旋-2') 和激活函数-2 (AF-2) 区域.
主要成果:
- 非极化力场导致PPAR-结位中关键键键的破坏,导致AF-2中的随机结构.
- 非极化模拟结果是,由于骨干键断裂,螺旋-2'的部分变性.
- 极化力场维持了PPAR-gamma-rosiglitazone复合体的稳定性,并保留了螺旋-2'的原生折叠结构,与实验数据一致.
结论:
- 蛋白质的电子极化对于稳定关键的键是必不可少的.
- 精确的蛋白质 - 配体相互作用建模,特别是PPAR - ,需要包括蛋白质两极化.
- 这项研究强调了两极化在维护PPAR-gamma的结构完整性及其功能性连接体结合形状方面的重要性.
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