叉头转录因子确定了S. cerevisiae中的起源时间和长距离聚类
Simon R V Knott1, Jared M Peace, A Zachary Ostrow
1Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA.
Cell
|January 24, 2012
概括
酵母叉头因子Fkh1和Fkh2通过聚类早期起源,在全球范围内控制DNA复制时间. 这些因素将起源招募到复制工厂,独立于转录水平.
科学领域:
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 细胞生物学 细胞生物学
背景情况:
- 细胞的染色体复制是通过复制起源的表观遗传调节在时间和空间上组织的.
- 复制起源时间与染色体环境和核定位有关,但机制尚不清楚.
研究的目的:
- 研究酵母叉头转录因子 (Fkh1和Fkh2) 在调节复制起源时间方面的作用.
- 阐明叉头因子影响DNA复制时间和空间组织的机制.
主要方法:
- 在缺乏Fkh1和Fkh2的酵母菌株中复制起源时间的分析.
- 研究起源与复制启动因子 (例如,Cdc45) 和起源识别复合体 (ORC) 的关联.
- 检查叉头因子,起源和ORC之间的物理相互作用.
主要成果:
- Fkh1和Fkh2被确定为复制起源时间的全球决定因素.
- 叉头因子调节的起源时间是独立于本地转录水平的.
- Fkh1和Fkh2对于早期复制起源的聚类和它们在G1阶段与Cdc45的关联至关重要.
- Fkh1和Fkh2与Fkh激活的起源结合,并与ORC物理相互作用,促进起源聚类.
结论:
- Fkh1和Fkh2在组织DNA复制时间方面发挥着至关重要的作用,通过向复制工厂招募来源.
- 这些发现提供了一种机制,解释了叉头因子如何对差异性起源发射和染色体域组织的表观遗传调节作出贡献.
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