MazF activation promotes translational heterogeneity of the grcA mRNA in Escherichia coli populations

PeerJ

article

Nela Nikolic¹  Zrinka Didara¹  Isabella Moll¹ 

[1] Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, Vienna Biocenter ,(VBC), University of Vienna;Institute of Science and Technology Austria;Department of Life Sciences, IMC University of Applied Sciences Krems

关键词: Toxin-antitoxin system;    mazEF module;    Phenotypic heterogeneity;    Gene expression;    Fluorescent reporter;    Flow cytometry;   

DOI  :  10.7717/peerj.3830

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Bacteria adapt to adverse environmental conditions by altering gene expression patterns. Recently, a novel stress adaptation mechanism has been described that allows Escherichia coli to alter gene expression at the post-transcriptional level. The key player in this regulatory pathway is the endoribonuclease MazF, the toxin component of the toxin-antitoxin module mazEF that is triggered by various stressful conditions. In general, MazF degrades the majority of transcripts by cleaving at ACA sites, which results in the retardation of bacterial growth. Furthermore, MazF can process a small subset of mRNAs and render them leaderless by removing their ribosome binding site. MazF concomitantly modifies ribosomes, making them selective for the translation of leaderless mRNAs. In this study, we employed fluorescent reporter-systems to investigate mazEF expression during stressful conditions, and to infer consequences of the mRNA processing mediated by MazF on gene expression at the single-cell level. Our results suggest that mazEF transcription is maintained at low levels in single cells encountering adverse conditions, such as antibiotic stress or amino acid starvation. Moreover, using the grcA mRNA as a model for MazF-mediated mRNA processing, we found that MazF activation promotes heterogeneity in the grcA reporter expression, resulting in a subpopulation of cells with increased levels of GrcA reporter protein.

【 授权许可】

CC BY