直接单细胞观察一个关键的大肠杆菌细胞周期振荡器
Ilaria Iuliani1,2,3, Gladys Mbemba1, Marco Cosentino Lagomarsino3,4
1LBPA, UMR 8113, CNRS, ENS Paris-Saclay, 91190 Gif-sur-Yvette, France.
Science advances
|July 17, 2024
概括
细胞大小控制了通过DnaA蛋白在大肠杆菌中启动DNA复制的过程. 研究人员观察了两个细胞周期振荡器,揭示了SeqA蛋白质.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 在大肠杆菌中,DNA复制的启动是由DnaA蛋白活性调节的,DnaA蛋白活性与细胞大小有关.
- DnaA蛋白活性振荡,但这些振荡在单细胞水平上没有直接观察到.
研究的目的:
- 为了研究在大肠杆菌中单细胞水平DnaA活动的振荡.
- 确定DnaA活动,细胞大小和DNA复制启动之间的关系.
主要方法:
- 在单个大肠杆菌细胞中测量了由DnaA调节的促进体控制的记者蛋白的体积特异性生产率.
- 根据记者蛋白生产,分辨和分析了两个不同的细胞周期振荡器.
主要成果:
- 确定了两个细胞循环振荡器:一个与DnaA活动和SeqA抑制相关,显示了与细胞大小和分裂的因果关系;另一个仅报告DnaA活动,失去了同步和因果关系.
- 证明SeqA介导的短暂基因表达抑制与细胞分裂同步DnaA活动振荡.
- 表明DnaA活动的峰值与DNA复制启动事件没有直接相关.
结论:
- 通过SeqA的调节作用,DnaA活动振荡与细胞大小和分裂相结合.
- 这项研究为控制大肠杆菌DNA复制启动和细胞周期进展的机制提供了新的见解.
- 通过SeqA抑制暂时的基因表达对于维持DnaA活性和细胞分裂之间的相位关系至关重要.
相关概念视频
The Cell Cycle Control System
The cell cycle is an organized set of events that leads the cell to divide into two daughter cells, each containing chromosomes identical to the parent cell. It is the cell cycle that leads to the formation of an entire organism from a single-cell zygote. Besides, cell division also functions in the renewal or repair of tissues in adult multicellular eukaryotes. For example, in the bone marrow, the stem cells divide to form new blood cells. Although essential for several functions, cell...
The Cell Cycle Control System
The cell cycle is an organized set of events that leads the cell to divide into two daughter cells, each containing chromosomes identical to the parent cell. It is the cell cycle that leads to the formation of an entire organism from a single-cell zygote. Besides, cell division also functions in the renewal or repair of tissues in adult multicellular eukaryotes. For example, in the bone marrow, the stem cells divide to form new blood cells. Although essential for several functions, cell...
The Cell Cycle Control System
The cell cycle regulation directs how a cell proceeds from one phase to the next and begins mitosis. The cell cycle control system includes intracellular regulatory molecules and external triggers. They provide "stop" or "advance" signals and operate at specific cell cycle stages termed checkpoints to ensure that a particular process is completed before the cell advances to the next phase.
Cyclins and cyclin-dependent kinases (Cdks) are the primary cell cycle regulators and function at the cell...
Cyclins and cyclin-dependent kinases (Cdks) are the primary cell cycle regulators and function at the cell...
Bacterial Flora of the Large Intestine
The gut microbiome is formed by a vast and diverse community of bacteria that colonizes our large intestine. These bacteria start residing in the gut from birth and continue diversifying throughout life, influenced by factors such as diet, lifestyle, and stress. The gut bacterial community also includes bacteria from food and those that enter the colon through the anus.
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.
Flagella and Motility in Bacteria
Flagella are specialized, thread-like structures that extend from a bacteria's cell envelope. They play a crucial role in motility and chemotaxis. Their structural organization and functioning exemplify sophisticated biological engineering, enabling bacterial survival and adaptability in diverse environments.Structure of the FlagellumA bacterial flagellum consists of three key components: the filament, the hook, and basal body. The filament, a long, helical structure composed of repeating...


