Regulation of Global Transcription in Escherichia coli by Rsd and 6S RNA

G3: Genes, Genomes, Genetics

Avantika Lal^1¹  Sandeep Krishna^2² 

[1] National Centre for Biological Sciences, and^1;Simons Centre for the Study of Living Machines, National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore 560065, Karnataka, India^2

关键词: gene regulation;    sigma factors;    RNA polymerase;    6S RNA;    Rsd;   

DOI  :  10.1534/g3.118.200265

学科分类：生物科学（综合）

来源: Genetics Society of America

【 摘 要 】

In Escherichia coli , the sigma factor σ⁷⁰ directs RNA polymerase to transcribe growth-related genes, while σ³⁸ directs transcription of stress response genes during stationary phase. Two molecules hypothesized to regulate RNA polymerase are the protein Rsd, which binds to σ⁷⁰, and the non-coding 6S RNA which binds to the RNA polymerase-σ⁷⁰ holoenzyme. Despite multiple studies, the functions of Rsd and 6S RNA remain controversial. Here we use RNA-Seq in five phases of growth to elucidate their function on a genome-wide scale. We show that Rsd and 6S RNA facilitate σ³⁸ activity throughout bacterial growth, while 6S RNA also regulates widely different genes depending upon growth phase. We discover novel interactions between 6S RNA and Rsd and show widespread expression changes in a strain lacking both regulators. Finally, we present a mathematical model of transcription which highlights the crosstalk between Rsd and 6S RNA as a crucial factor in controlling sigma factor competition and global gene expression.

【 授权许可】

CC BY