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转录因子凝聚物,3D聚类和MET调节体的基因表达增强
James Lee1,2,3, Leman Simpson2,4, Yi Li1,2
1Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, United States.
eLife
|September 30, 2024
概括
转录因子 (TFs) 形成凝聚物,组织3D基因组. 在酵母中,Met4和Met32在甲因饥饿时形成核点,增强甲因生物合成的基因表达.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 遗传学 是一个
背景情况:
- 转录因子 (TF) 可以经历液-液相分离 (LLPS) 形成凝结物.
- 在3D基因组组织和基因调节中,TF凝结物的作用尚未完全被理解.
- 酵母中的 metionin (met) 生物合成基因由 TF Met4 和 Met32 等协同激活剂调节,以应对甲饥饿.
研究的目的:
- 在3D基因组组织和基因调控中研究TF凝聚物的功能.
- 确定Met4和Met32是否在体内形成凝结物,以及这些凝结物是否参与了目标基因的组织.
- 阐明TF凝结物对转录对 metionin 枯竭的反应有所贡献的机制.
主要方法:
- 使用显微镜观察酵母核中的内源Met4和Met32局部化.
- 在实验室中使用复合Met4和Met32蛋白进行相位分离试验.
- 使用显微镜分析 Met4 puncta 与目标基因和染色质的同定位.
- 评估MET3pr-GFP记者基因的转录活动.
- 一个Met4突变的特征与一个截断的内在乱区域 (IDR).
主要成果:
- 内源的Met4和Met32在甲素耗尽后,在酵母核中形成共同局部化的点.
- 再组合的Met4和Met32在体外表现出LLPS特性,形成混合滴.
- Met4 puncta与目标基因共同定位,这些基因以Met4依赖的方式在3D中聚集在一起.
- 一个MET3pr-GFP记者显示了增强的转录活性和与Met4点的同定位.
- 一个具有部分IDR截断的Met4突变体显示了减少的点形成,并选择性地降低了记者活动.
结论:
- Met4和协同激活剂形成核凝聚物,在3D中组织目标基因方面发挥着至关重要的作用.
- 这些凝结物促进了局部TF度的增加,从而导致强大的转录反应对 metionin饥饿.
- TF凝聚物的形成和功能对于有效的基因调节和适应环境信号至关重要.
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