Quality control of bacterial mRNA decoding and decay

Abstract

Studies in eukaryotes and prokaryotes have revealed that gene expression is not only controlled through altering the rate of transcription but also through varying rates of translation and mRNA decay. Indeed, the expression level of a protein is strongly affected by the steady state level of its mRNA. RNA decay can, along with transcription, play an important role in regulating gene expression by fine-tuning the steady state level of a given transcript and affecting its subsequent decoding during translation. Alterations in mRNA stability can in turn have dramatic effects on cell physiology and as a consequence the fitness and survival of the organism. Recent evidence suggests that mRNA decay can be regulated in response to environmental cues in order to enable the organism to adapt to its changing surroundings. Bacteria have evolved unique post transcriptional control mechanisms to enact such adaptive responses through: 1) general mRNA decay, 2) differential mRNA degradation using small non-coding RNAs (sRNAs), and 3) selective mRNA degradation using the tmRNA quality control system. Here, we review our current understanding of these molecular mechanisms, gleaned primarily from studies of the model gram negative organism E. coli, that regulate the stability and degradation of normal and defective transcripts.

Codon influence on protein expression in E. coli correlates with mRNA levels

“…5d and Extended Data Figs. 6d and 8 ) and that these parameters are tightly coupled 45 , as previously shown for some individual genes 2,36,46,47 . Recent reports suggest similar coupling in yeast 29,30 .…”

YmdB: a stress-responsive ribonuclease-binding regulator of E. coli RNase III activity

“…The first suggestion that the ribonucleolytic actions of RNase III may be regulated came from the observation by Makarov and Apirion in 1992 that extracts of E. coli cells contain an ∼17-kDa protein that can inhibit in vitro RNase III-dependent processing of p10Sa RNA (Makarov and Apirion 1992)-a 10Sa RNA precursor (also known as ssrA RNA and tmRNA) that has an important role in the recycling of ribosomes from defective mRNAs (Richards et al 2008). However, the nature of this RNase IIIinhibiting moiety and its possible biological role(s) has remained obscure for almost two decades.…”

Expression and inducibility of endosulfan metabolizing gene in Rhodococcus strain isolated from earthworm gut microflora for its application in bioremediation

“…At 20 lg/ml endosulfan concentration all the bands of 5s, 16s and 23s rRNA was clearly visible. Richards et al (2008) reported that RNA decay play an important role in regulating the gene expression. Alterations in mRNA stability may have dramatic effects on cell physiology and as a consequence the fitness and survival of the organism.…”