依赖光的黄素氧化还原和添加状态控制着转录因子EL222的构造和DNA结合活性
Aditya S Chaudhari1,2, Adrien Favier3, Zahra Aliakbar Tehrani4
1Laboratory of Biomolecular Recognition, Institute of Biotechnology of the Czech Academy of Sciences, Vestec 25250, Czech Republic.
Nucleic acids research
|March 22, 2025
概括
光氧电压/螺旋转螺旋 (LOV-HTH) 光感应器EL222
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 摄影生物学 摄影生物学
背景情况:
- EL222是一种由光调节的LOV-HTH光受体.
- 它的活性取决于蛋白质-蛋白质和蛋白质-DNA相互作用.
- 其flavin mononucleotide (FMN) 辅因子的光刺激触发了这些相互作用.
研究的目的:
- 为了阐明EL222光循环的分子机制.
- 了解FMN光刺激是如何调节EL222形态和DNA结合的.
主要方法:
- 大分子X射线晶体学 (MX)
- 核磁共振 (NMR) 光谱学 核磁共振 (NMR) 光谱学
- 光学光谱仪 (红外线,紫外线-Vis)
- 分子动力学/元动力学 (MD/metaD) 模拟
- 使用非正规氨基酸的蛋白质工程.
主要成果:
- 确定了两个与不同FMN状态相对应的光诱导构造 (lit1,lit2).
- 观察到单体形式的微妙结构变化,但在光激活状态下进行单体二次体交换.
- 在所有EL222物种中证明了依赖光的DNA结合,在蓝光照射时形成稳定的复合体.
结论:
- 光诱导的FMN变化将EL222驱动到一个开放的形状.
- 这种开放的构造促进了自我关联和DNA结合.
- 提出了一个EL222激活模型,涉及FMN介导的构造变化.
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