细胞大小调节SBF和Whi5染色体结合,以调节发芽酵母细胞周期的开始
bioRxiv : the preprint server for biology
|February 27, 2026
概括
细胞大小通过调节Whi5和SBF与染色素的结合来控制发芽酵母中的Start过渡. 这种调节确保了细胞周期的正确进展和分裂.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 细胞生长和分裂与细胞大小协调在一起.
- 在芽的酵母中,细胞大小通过转录因子SBF.影响G1/S过渡 (Start).
- 作为SBF抑制剂的Whi5随着细胞的生长而降低度,从而有助于大小控制.
研究的目的:
- 阐明细胞大小和SBF调节的促进子活性之间的机制联系.
- 量化活芽酵母细胞中Whi5和SBF与染色素的结合动力学.
主要方法:
- 使用单分子光显微镜来追踪Whi5和SBF结合动态.
- 测量了Whi5和SBF的染色质结合亲缘关系和停留时间,与细胞大小相关.
- 在各种条件下分析了SBF和Whi5的细胞拷贝数比.
主要成果:
- 增加细胞大小与减少Whi5染色体亲和力和增加SBF染色体亲和力相关.
- 与染色质结合的SBF与Whi5分子的比率随着细胞大小的增加而增加.
- 随着细胞的生长,Whi5与染色质的结合减少,促进SBF激活和G1环林 (CLN1,CLN2) 的表达.
结论:
- 细胞大小信息通过SBF和Whi5丰度的变化以及它们的染色体协会传递到基因组.
- 这些分子事件调节大小依赖的开始过渡,确保精确的细胞大小控制.
- Whi5作为一个关键的调节器,限制SBF对染色质的访问,直到细胞达到关键大小.
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