HIF异构体的上下文依赖性变异性影响与宏分子和小分子伙伴的相互作用
bioRxiv : the preprint server for biology
|June 12, 2025
概括
缺氧诱导因子 (HIFs) 在扩展的DNA上形成新的"异构体的二分体" (DoHD) 复合体,影响连接体和协同激活体的结合. 这些发现揭示了HIF在细胞反应中的复杂调节机制.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 低氧诱导因子 (HIF) 是关键的转录因子,调节细胞对低氧反应.
- 现有的HIF结构数据主要涉及短DNA片段,限制了对较长DNA,小分子和蛋白质协活性剂的相互作用的理解.
- 在复杂的生物环境中,HIF组装和调节的精确机制仍然不完全理解.
研究的目的:
- 研究HIF组合与DNA,小分子和蛋白质合作伙伴的结构和生化基础.
- 阐明新型HIF复合物的形成和特征,特别是在扩展的DNA序列上.
- 了解分子背景和动态如何影响HIF相互作用和监管潜力.
主要方法:
- 电子显微镜 (cryo-EM) 用于确定HIF复合体的高分辨率结构.
- 生物化学测试以评估连接体结合和蛋白质相互作用.
- 通过质谱学 (HDX-MS) 进行-交换,以探测HIF组件的动态方面.
主要成果:
- 发现了一种新型的"异构体的二分体" (DoHD) 复合体,其中两个HIF异构体与扩展的DNA序列结合.
- 鉴定与较大的DoHD复合体对孤立的HIF域结合的差异性连接体.
- 对HIF异构体与TACC3协活性剂的接触的特征,取决于子单元组成和复合物形成.
结论:
- HIFs可以在扩展的DNA上形成复杂的,更高级的组件,如DoHDs,改变它们的相互作用配置.
- 与HIFs结合的联体和协同激活剂对该复合物的特定分子环境和动态敏感.
- 这些发现为HIF和相关的转录因子的复杂监管提供了关键的见解.
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