无序蛋白对拥挤环境的敏感度研究

在细胞内，无序蛋白处于相对拥挤的环境中，因此探究无序蛋白在拥挤环境下的敏感性具有重要意义。

本文通过分子动力学模拟手段研究了IDR1 无序蛋白在拥挤环境中的构象变化，通过PEG 分子模拟拥挤环境，探究不同浓度和链长PEG 分子所造成的拥挤条件下IDR1 蛋白构象的变化。模拟结果表明环境拥挤程度对无序蛋白端到端距离和结构具有显著影响，在单体水平上证明了无序蛋白对拥挤环境的敏感性，并且模拟采用PEG 链长越长，无序蛋白结构和端到端距离收缩更明显。在不同环境拥挤程度对Part-IDR1 体系进行模拟分析，结果表明无序区域对IDR1 响应拥挤环境十分重要，并揭示了IDR1 蛋白无序结构域与有序结构域之间的相互调节机制，无序结构域使得IDR1 两个𝛼-螺旋更加开放的结构去响应拥挤环境，表现为有序结构域逐渐收缩。

总之，本论文为深入理解无序蛋白在拥挤环境下蛋白质各结构域之间相互调节进而响应外界环境等方面提供了新的思路。同时，研究结果也强调了无序区域在无序蛋白中的重要性，为未来相关领域的研究提供了参考。

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