Escherichia coli RNase E and RNase G cleave a Bacillus subtilis transcript at the same site in a structure-dependent manner

Abstract

The decay of Bacillus subtilis aprE leader- lacZ mRNA was examined in Escherichia coli wild-type and in mutants deficient in RNase E, RNase G, or both. Two versions of the mRNA were studied: the wild-type mRNA, which has a stem-loop at the 5' end, and a mutant mRNA, with a single-stranded 5' end. The half-life of both transcripts was determined by RNase E, the half-life of the mutant transcript being one-third of that of the wild-type transcript. RNase G cleaved both transcripts at a site within an AU-rich sequence in the stem-loop region, but cleavage was much more efficient when the stem-loop was destabilized. RNase E cleaved at the same site, but less efficiently and only in the mutant transcript.

The Novel Two-Component Regulatory System BfiSR Regulates Biofilm Development by Controlling the Small RNArsmZthrough CafA

“…RNase G is a homologue of the essential E. coli RNase, RNase E. Whereas RNase E plays a key role in the degradation of mRNA and the processing of tRNA and rRNA in E. coli, the biological functions of RNase G appear more limited. While both ribonucleases share the propensity to cleave RNA within single-stranded segments that are AU rich and prefer RNA substrates that bear a single phosphate group at the 5Ј end (22,25,68), RNase G has been confirmed to be required in E. coli only for adhE and eno mRNA (encoding alcohol dehydrogenase and enolase, respectively) decay and 16S rRNA processing (26, 32, 69, 71). However, the findings that cafA overexpression restores viability of an RNase E deletion mutant and reduces the accumulation of approximately 100 transcripts (31) suggest a broader role for RNase G in RNA processing.…”