title: A Spatial Control for Correct Timing of Gene Expression during the Escherichia coli Cell Cycle.
abstract: Temporal transcriptions of genes are achieved by different mechanisms such as dynamic interaction of activator and repressor proteins with promoters, and accumulation and/or degradation of key regulators as a function of cell cycle. We find that the TorR protein localizes to the old poles of theEscherichia colicells, forming a functional focus. The TorR focus co-localizes with the nucleoid in a cell-cycle-dependent manner, and consequently regulates transcription of a number of genes. Formation of one TorR focus at the old poles of cells requires interaction with the MreB and DnaK proteins, and ATP, suggesting that TorR delivery requires cytoskeleton organization and ATP. Further, absence of the protein-protein interactions and ATP leads to loss in function of TorR as a transcription factor. We propose a mechanism for timing of cell-cycle-dependent gene transcription, where a transcription factor interacts with its target genes during a specific period of the cell cycle by limiting its own spatial distribution.
authors.affiliation: School of Life Sciences, Inner Mongolia University, Hohhot 010021, China. zhjyq129@163.com.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yao
authors.affiliation: School of Life Sciences, Inner Mongolia University, Hohhot 010021, China. lifei.fan@life.imu.edu.cn.
authors.forename: Lifei
authors.initials: L
authors.lastname: Fan
authors.affiliation: School of Life Sciences, Inner Mongolia University, Hohhot 010021, China. yixin.shi@asu.edu.|School of Life Sciences, Arizona State University, Tempe, AZ 85287-4501, USA. yixin.shi@asu.edu.
authors.forename: Yixin
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Department of Public Health Sciences, Karolinska Institutet, SE-171 77 Stockholm, Sweden. Ingvild.odsbu@gmail.com.
authors.forename: Ingvild
authors.initials: I
authors.lastname: Odsbu
authors.affiliation: School of Life Sciences, Inner Mongolia University, Hohhot 010021, China. morigenm@hotmail.com.
authors.lastname: Morigen
keywords: TorR focus; cell-cycle-dependent; co-localization; gene expression; nucleoid; spatial control