Dataset Information

Role of RNase Y in Clostridium perfringens mRNA Decay and Processing.

ABSTRACT: RNase Y is a major endoribonuclease that plays a crucial role in mRNA degradation and processing. We study the role of RNase Y in the Gram-positive anaerobic pathogen Clostridium perfringens, which until now has not been well understood. Our study implies an important role for RNase Y-mediated RNA degradation and processing in virulence gene expression and the physiological development of the organism. We began by constructing an RNase Y conditional knockdown strain in order to observe the importance of RNase Y on growth and virulence. Our resulting transcriptome analysis shows that RNase Y affects the expression of many genes, including toxin-producing genes. We provide data to show that RNase Y depletion repressed several toxin genes in C. perfringens and involved the virR-virS two-component system. We also observe evidence that RNase Y is indispensable for processing and stabilizing the transcripts of colA (encoding a major toxin collagenase) and pilA2 (encoding a major pilin component of the type IV pili). Posttranscriptional regulation of colA is known to be mediated by cleavage in the 5' untranslated region (5'UTR), and we observe that RNase Y depletion diminishes colA 5'UTR processing. We show that RNase Y is also involved in the posttranscriptional stabilization of pilA2 mRNA, which is thought to be important for host cell adherence and biofilm formation.

Importance

RNases have important roles in RNA degradation and turnover in all organisms. C. perfringens is a Gram-positive anaerobic spore-forming bacterial pathogen that produces numerous extracellular enzymes and toxins, and it is linked to digestive disorders and disease. A highly conserved endoribonuclease, RNase Y, affects the expression of hundreds of genes, including toxin genes, and studying these effects is useful for understanding C. perfringens specifically and RNases generally. Moreover, RNase Y is involved in processing specific transcripts, and we observed that this processing in C. perfringens results in the stabilization of mRNAs encoding a toxin and bacterial extracellular apparatus pili. Our study shows that RNase activity is associated with gene expression, helping to determine the growth, proliferation, and virulence of C. perfringens.

SUBMITTER: Obana N

PROVIDER: S-EPMC5198488 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Role of RNase Y in Clostridium perfringens mRNA Decay and Processing.

Obana Nozomu N Nakamura Kouji K Nomura Nobuhiko N

Journal of bacteriology 20161228 2

RNase Y is a major endoribonuclease that plays a crucial role in mRNA degradation and processing. We study the role of RNase Y in the Gram-positive anaerobic pathogen Clostridium perfringens, which until now has not been well understood. Our study implies an important role for RNase Y-mediated RNA degradation and processing in virulence gene expression and the physiological development of the organism. We began by constructing an RNase Y conditional knockdown strain in order to observe the impor ...[more]

PMID: 27821608

Similar Datasets

Project description:Epsilon toxin (ETX), a pore-forming toxin produced by type B and D strains of Clostridium perfringens, mediates severe enterotoxemia in livestock and possibly plays a role in human disease. During enterotoxemia, the nearly inactive ETX prototoxin is produced in the intestines but then must be activated by proteolytic processing. The current study sought to examine ETX prototoxin processing and activation ex vivo using the intestinal contents of a goat, a natural host species for ETX-mediated disease. First, this study showed that the prototoxin has a KEIS N-terminal sequence with a molecular mass of 33,054 Da. When the activation of ETX prototoxin ex vivo by goat small intestinal contents was assessed by SDS-PAGE, the prototoxin was processed in a stepwise fashion into an ~27-kDa band or higher-molecular-mass material that could be toxin oligomers. Purified ETX corresponding to the ~27-kDa band was cytotoxic. When it was biochemically characterized by mass spectrometry, the copresence of three ETX species, each with different C-terminal residues, was identified in the purified ~27-kDa ETX preparation. Cytotoxicity of each of the three ETX species was then demonstrated using recombinant DNA approaches. Serine protease inhibitors blocked the initial proteotoxin processing, while carboxypeptidase inhibitors blocked further processing events. Taken together, this study provides important new insights indicating that, in the intestinal lumen, serine protease (including trypsin and possibly chymotrypsin) initiates the processing of the prototoxin but other proteases, including carboxypeptidases, then process the prototoxin into multiple active and stable species. Importance: Processing and activation by intestinal proteases is a prerequisite for ETX-induced toxicity. Previous studies had characterized the activation of ETX using only arbitrarily chosen amounts of purified trypsin and/or chymotrypsin. Therefore, the current study examined ETX activation ex vivo by natural host intestinal contents. These analyses demonstrated that (i) ETX processing in host intestinal contents occurs in an ordered, stepwise fashion, (ii) processing of prototoxin by host intestinal contents results in higher-molecular-mass material and 3 distinct ~27-kDa ETX species, and (iii) serine proteases, such as trypsin, chymotrypsin, and other proteases, including carboxypeptidases, play a role in the activation of ETX by intestinal contents. These studies provide new insights into the activation and processing of ETX and demonstrate that this process is more complicated than previously appreciated.

Dataset Information

Role of RNase Y in Clostridium perfringens mRNA Decay and Processing.

Importance

Publications

Role of RNase Y in Clostridium perfringens mRNA Decay and Processing.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets