单分子研究揭示Hmo1,而不是Hho1,促进了青芽酵母的染色体组合
Mengxue Wang1,2, Jinghua Li3, Yong Wang1,2
1State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences , Beijing, China.
mBio
|July 11, 2023
概括
在芽起的酵母中,Hmo1,而不是Hho1,充当链接组合基因素H1的功能,对染色质组装和紧缩至关重要. Hmo1表现出相分离和细胞循环依赖的酸化,类似于metazoan H1.
科学领域:
- * 分子生物学 * 分子生物学
- * 表观遗传学 是一种表观遗传学.
- * 染色体生物学
背景情况:
- *链接组合素H1对于真核染色体组织和基因调节至关重要.
- * 在*Saccharomyces cerevisiae* (起芽酵母) 中,链接组合素H1的身份和功能仍在争论中.
- *Hho1和Hmo1是初芽酵母中H1链接激素的主要候选者.
研究的目的:
- * 为了确定哪个候选物质,Hho1或Hmo1,在芽酵母中起到作为链接组合素H1的作用.
- *阐明这些基因组候选物在染色质组装和组织中的功能背后的分子机制.
- * 为了比较Hmo1和Hho1的功能性和结构性质与正规链接基因组 H1.
主要方法:
- * 单分子力光谱法使用磁子.
- *酵母核等离子提取物 (YNPE) 模仿生理核条件.
- * 总内部反射光显微镜用于观察DNA-蛋白相互作用.
主要成果:
- *单分子观察证实了Hmo1在染色质组装中的作用,而Hho1没有.
- * Hmo1的富含氨酸的C端域 (CTD) 对于染色体紧缩至关重要.
- *Hmo1,与Hho1不同,经历了可逆相分离与双链DNA,并显示细胞周期依赖的酸化.
结论:
- *Hmo1表现出芽酵母中链接素H1的关键功能,包括染色质组装和紧缩.
- * Hho1的功能受到其C端球状域的阻碍,与Hmo1的功能CTD不同.
- *这项研究澄清了长期以来关于芽酵母中左侧组合素H1的争论,并提供了对真核生物中组合素H1演变的见解.
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