RNA degradation in Bacillus subtilis: an interplay of essential endo‐ and exoribonucleases | Semantic Scholar (2024)

The findings suggest that the interactions of the enzymes involved in RNA degradation in B. subtilis are rather transient, and the bulk of these enzymes is located in the cytoplasm.

The effect of citrate, c-di-GMP and c- di-AMP, as well as enolase and phosphofructokinase, on the RNA degradation activity of PNPase is studied, which confirms the interaction of the RNases J1 and J2 through the C-terminal domain, and shows that they oligomerize as dimers and tetramers.

This work shows that S. aureus RNase J1 is a manganese dependent hom*odimeric enzyme with strong 5′ to 3′ exo-ribonuclease as well as endo- ribonucleasing activity and demonstrates that SauJ1 can efficiently degrade 5′ triphosphorylated RNA.

Characterization of the RNase E‐PNPase interaction in α‐proteobacteria, γ‐protesobacteria and cyanobacteria suggests that it arose independently several times during evolution, thus conferring an advantage in control and coordination of RNA processing and degradation.

Global mapping of mRNA decay intermediate 3′ ends within coding sequences was performed in strains that were either deleted for or had an inactivating point mutation in the pnpA gene, confirming the primary role of PNPase in mRNA turnover and suggesting the involvement of one or more unknown RNases.

The role of RNase Y in the Gram-positive anaerobic pathogen Clostridium perfringens, which until now has not been well understood, is studied to imply an important role forRNase Y-mediated RNA degradation and processing in virulence gene expression and the physiological development of the organism.

The findings suggest that the different helicases make distinct contributions to the physiology of B. subtilis, and the deletion of cshA, cshB, or yfmL leads to cold-sensitive phenotypes, suggesting distinct functions for the individual enzymes in this process.

It is shown that Alr1240, a member of the RNB family of exoribonucleases, could be co-isolated with RNase E from the lysate of the cyanobacterium Anabaena PCC 7120, andRNase E and RNase II form a compact complex in vivo by a fluorescence resonance energy transfer (FRET) assay.

At the physiological level, it was showed that RNase J1 is essential, whereas RNases J2 and III have a role in cold, oxidative and bile salts stress response, and RNase Y in general fitness, and interestingly, CshC is also involved in the expression control of CshA by a hitherto unprecedented mechanism.

A significant result from the PARE analysis was the discovery of an endonuclease cleavage just 2 nts downstream of the 16S rRNA 3′ end, which begins to answer, at least for B. subtilis, a long-standing question on the exon nucleolytic versus endonucleolytic nature of 16s rRNA maturation.

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Novel evidence is provided for the idea that RNase Y is the functional equivalent of RNase E, even though the two enzymes do not share any sequence similarity.

This review focuses on the enzymes and pathways of RNA processing and degradation in Bacillus subtilis, and compares them to those of its gram-negative counterpart, Escherichia coli, to reveal that B. subtili has a very different selection of RNases available for RNA maturation.

The results presented in this work emphasize the importance of RNase Y as the global acting endoribonuclease for B.‚subtilis as well as other Gram‐positive bacteria.

The results suggest that CshA is the functional equivalent of the RhlB helicase of the Escherichia coli RNA degradosome.

Although the abundance of a large number of transcripts was altered by depletion of RNase III, this appears to result primarily from indirect transcriptional effects, RNase depletion led to the stabilization of many low-abundance potential regulatory RNAs, both in intergenic regions and in the antisense orientation to known transcripts.

RNA degradosome-like complexes appear to be conserved throughout the Proteobacteria, but there is a surprising variability in composition that might contribute to the adaptation of these bacteria to the enormously wide variety of niches in which they live.

Half‐life measurements of individual mRNAs show that RNases J1/J2 can alter gene expression by modulating transcript stability, suggesting a complex role of these ribonucleases in both degradative and regulatory processing events that have an important impact on gene expression.

RNase Y might be not only important for riboswitch RNA turnover but also as a key player in the initiation of mRNA decay in B. subtilis.

The purification and identification by mass spectrometry in Bacillus subtilis of two paralogous endoribonucleases, here named RNases J1 and J2, which share functional hom*ologies with RNase E but no sequence similarity are reported.

This is the first report of a specific mRNA whose stability is determined by RNase Y, and provides strong evidence that endonuclease cleavage in the body of the message, rather than degradation from the native 3' end, is the rate-determining step for mRNA decay.

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