调节转录因子DNA结合选择性的pH动态的作用
bioRxiv : the preprint server for biology
|June 3, 2024
概括
细胞内pH动态通过改变转录因子DNA结合直接调节基因表达. 在转录因子中保存的histidine作为pH传感器,影响细胞行为.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生化学
背景情况:
- 细胞内pH值 (pHi) 调节细胞的重要功能,如增殖和分化.
- 通过转录因子直接控制基因表达的pHi的作用仍然在很大程度上未被探索.
- 蛋白质中的histidine残留物是检测pH值变化的关键.
研究的目的:
- 为了调查它们的DNA结合域 (DBDs) 中含有histidine的转录因子是否表现出pH调节的活性.
- 确定pHi动态是否可以通过转录因子函数直接调节基因表达.
- 为了确定受pH值变化影响的特定转录因子和DNA基因.
主要方法:
- 通过指数式丰富对联体的系统进化,然后进行测序 (SELEX-seq),以确定依赖pH的DNA结合动机.
- 电泳运动转移试验 (EMSAs) 用于量化不同pH值的FOX转录因子的结合亲缘关系.
- RNA测序 (RNA-seq) 用于分析全球基因表达变化,以应对pHi变异.
- 位点定向突变发生,以评估特定的胺残留在pH依赖DNA结合中的作用.
主要成果:
- 在SELEX-seq中,针对FOX家族转录因子,确定了pH依赖的DNA基因特征偏好.
- 与FkhP动机的FOXC2,FOXM1和FOXN1的结合亲缘关系在pH 7.0时明显高于pH 7.5.5时.
- 在细胞中较低的细胞内pH值时,FOXC2对FkhP动机表现出增强的活性,这取决于保存的胺 (His122).
- RNA-seq揭示了与FOXC2活性相关的促进因子的pH依赖的丰富.
结论:
- 转录因子在其DBD中含有histidine,可以作为pH传感器,直接调节DNA结合和基因表达.
- 在调节转录因子选择性和细胞行为方面,pHi动态起着至关重要的作用.
- 这种pH调节的转录因子-DNA结合机制与各种家族的超过85种转录因子相关,并影响各种细胞过程.
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