YfiA、Rmf和Hpf影响大肠杆菌DNA复制起始

YfiA, Rmf and Hpf Affect the Initiation of DNA Replication in Escherichia coli

探讨核糖体休眠因子yfiA、rmf和hpf对大肠杆菌DNA复制起始的影响。观察ΔyfiA、Δrmf和Δhpf基因缺失突变体的DNA复制式样、细胞倍增时间、细胞大小等表型变化,并使用温度敏感性实验和蛋白定量实验探究yfiA、rmf和hpf对DNA复制起始的作用机理。结果发现,相较于野生型细胞,ΔyfiA、Δrmf和Δhpf突变体出现DNA复制起始的延迟、细胞倍增时间延长、细胞体积减小等表型变化。温度敏感性试验表明YfiA、RMF和HPF蛋白不是直接通过与DnaA、DnaB或DnaC蛋白相互作用来影响DNA复制起始。蛋白定量实验表明它们可能是通过减少细胞内总蛋白的量,包括DnaA蛋白,使细菌的代谢和生长速度减慢,从而导致细菌DNA复制起始发生延迟、细胞倍增时间延长和体积减小等表型改变。这为深入研究yfiA、rmf和hpf的功能提供基础。

To investigate the effect of ribosome hibernation factor yfiA,rmf and hpf on the initiation of E.coli DNA replication,the phenotype changes including DNA replication pattern,doubling time and cell size ofΔyfiA,Δrmf and Ahpf mutantswere observed,and the temperature sensitivity test and proteinquantification experiments were performed to study the mechanismof DNA replication initiationinfluenced by yfiA,rmf and hpf.The results showed that compared with the wild-type,the delayed initiation of DNA replication,prolonged doubling time and declined cell sizewere observed inΔyfiA,Δrmf andΔhpf cells.The temperature sensitive test demonstrated that YfiA,RMF and HPF protein affected theinitiation of DNA replication was not through directly interacting with DnaA,DnaB or DnaC protein.The protein quantification experiments suggested that they might through reducing the amount of total protein in cells,including DnaA protein,slowed down bacterial metabolism and growth rate,leading to the delayed DNA replication initiation,prolonged doubling time and decreased cell size in bacterial cells.These provide the basis for in-depth studying the functions of yfiA,rmf and hpf.