Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

RNase III CLASH in MRSA uncovers sRNA regulatory networks coupling metabolism to toxin expression

ABSTRACT: Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterial pathogen responsible for high levels of human morbidity and mortality. MRSA co-ordinates expression of an array of bacterial factors involved in antimicrobial resistance, nutrient acquisition and immune evasion in the host. Post-transcriptional regulation by small RNAs (sRNAs) has emerged as an important mechanism for the control of MRSA virulence. However, the function of the majority of sRNAs during infection is unknown. To address this gap in understanding, we performed UV cross-linking, ligation and sequencing of hybrids (CLASH) in MRSA to unravel sRNA-RNA interactions under conditions that mimic the host environment. Using double stranded ribonuclease III (RNase III) as a bait we not only uncovered known interactions but also hundreds of novel sRNA-RNA pairs. Strikingly, our results suggest that the production of small membrane-permeabilizing toxins is under extensive sRNA-mediated regulation and that their expression is intimately connected to metabolism. Importantly, we discovered that two sRNAs, RNAIII and RsaE, control the expression of at least four cytolytic toxins that are important for MRSA virulence. Taken together, we present a comprehensive analysis of sRNA-target interactions in S. aureus and provide detail on how these contribute to the control of virulence in response to changes in metabolism.

ORGANISM(S): Staphylococcus aureus

PROVIDER: GSE166151 | GEO | 2022/05/04

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

RNase III CLASH uncovers sRNA regulatory networks coupling metabolism to production of cytolytic toxins in methicillin resistant Staphylococcus aureus

Project description:Methicillin resistant Staphylococcus aureus (MRSA) is an infectious pathogen that poses a significant threat to human health. MRSA is renowned for its ability to adapt to and even thrive in hostile environment within its host. By expressing a battery of virulence factors and toxins, MRSA is able to scavenge effectively essential nutrients and evade the immune system within the host. Post-transcriptional regulation by sRNAs contributes significantly to regulating the expression of virulence factors and toxins. However, the roles of the vast majority of sRNAs during host adaptation remain unknown. To challenge this gap, we performed UV cross-linking, ligation and sequencing of hybrids (CLASH) in S. aureus to unravel sRNA-RNA interactions with the double stranded ribonuclease III (RNase III) as a bait under conditions that mimic the host environment. Here we report a global analysis of RNA-RNA interactions in MRSA in vivo, which uncovered hundreds of novel sRNA-RNA pairs. Strikingly, our results indicate that the production of small membrane-permeabilizing toxins is under extensive sRNA-mediated regulation and that their expression is intimately connected to metabolism. We show that at least two sRNAs, RNAIII and RsaE, enhance the production of five clinically relevant cytolytic toxins that are important for survival within the host. Taken together, our data greatly expands the repertoire of sRNA-target interactions in S. aureus and provide detail on how these contribute to adjusting virulence in response to changes in metabolism.

2022-06-16 | PXD025122 | Pride

The small RNA SprY controls RNAIII function and affects Staphylococcus aureus virulence

Project description:While a plethora of small regulatory RNAs (sRNAs) have been identified in the human pathogen Staphylococcus aureus, the physiological function of most of them remains unknown. We report the characterization of SprY, a sRNA from S. aureus expressed from a pathogenicity island. RNAIII, a major regulator of S. aureus virulence, was discovered as a potential SprY target by an MS2-affinity purification assay. In silico interaction studies suggest a RNA-RNA pairing between the SprY 5’end and the 13rd stem-loop of RNAIII. Overproduction of SprY leads to a 1.5-fold reduction of RNAIII amount. By affecting the rnaIII expression, SprY affects the amount of RNAIII known targets. Indeed, SprY downregulates hla mRNA translation, but also upregulates other secreted factors such as Ecb and Rot. Furthermore, SprY decreases the hemolytic activity and virulence of S. aureus. Our results lead to propose that SprY is involved in S. aureus virulence through a post-transcriptional regulation of RNAIII.

2021-02-10 | GSE166499 | GEO

Evolution of virulence control by the staphylococcal agr quorum-sensing regulator

Project description:The Staphylococcus aureus accessory gene regulator (agr) is a prototype quorum-sensing system in Gram-positive bacteria and a paradigmatic example of gene regulation by a small regulatory RNA, RNAIII. Using genome-wide transcriptional profiling in the community-associated methicillin-resistant (CA-MRSA) strain MW2, we demonstrate here that in contrast to the current model of target gene regulation by agr, a large subset of agr-regulated genes is controlled independently of RNAIII. This group comprised predominantly metabolism genes, whereas virulence factors were mostly controlled by RNAIII. Remarkably, the phenol-soluble modulin (PSM) leukocidin genes were the only virulence determinants under RNAIII-independent control, emphasizing their exceptional role in S. aureus physiology and pathogenesis. Of note, PSM promoters bound the AgrA response regulator protein, previously believed to interact exclusively with agr promoters, explaining the exceptionally strict control of PSMs by agr. Our results suggest that virulence factor control is a secondary acquisition of the agr regulon, which evolved by development of RNAIII around the mRNA of the PSM d-toxin, exemplifying how gene control via a small regulatory RNA may be linked to a pre-established regulatory circuit. In addition to elucidating agr control in CA-MRSA, which revealed features potentially crucial for CA-MRSA pathogenesis, our study establishes a novel two-level model of cell-density dependent gene regulation in S. aureus and gives important insight into the connection of metabolism and virulence control in this leading opportunistic pathogen. Keywords: Wild type control vs mutant Wild type in triplicate is compared to mutant in triplicate totalling 27 samples

2010-05-14 | E-GEOD-10165 | biostudies-arrayexpress

Evolution of virulence control by the staphylococcal agr quorum-sensing regulator

2009-01-05 | GSE10165 | GEO

MRSA temporal adaptation to the healthy and influenza injured lung microenvironment

Project description:Influenza-induced respiratory failure is substantially worsened by secondary bacterial infections such as methicillin-resistant Staphylococcus aureus (MRSA). The bidirectional interaction between the influenza-injured lung microenvironment and MRSA is poorly understood. By conditioning MRSA ex vivo in bronchoalveolar lavage (BAL) fluid collected from mice at various timepoints of influenza infection, we found that influenza-injured lung microenvironment induces MRSA to increase cytotoxin expression while decreasing metabolic pathways. This overall increase in MRSA virulence was dependent upon SaeRS, a bacterial two-component system. Once expressed by MRSA, these influenza-induced toxins (such as Hla and LukAB) interact with host heparan sulfate (HS) fragments shed into the airspace. Highly-sulfated HS fragments augmented Hla- and LukAB-toxicity in vitro and in vivo. Our findings indicate that post-influenza MRSA pneumonia is shaped by bidirectional host-pathogen interactions: host injury triggers changes in bacterial expression of toxins, the activity of which are then shaped by host-derived HS fragments.

2022-11-29 | GSE199708 | GEO

Staphylococcus aureus induces a muted host response in human blood that blunts the recruitment of neutrophils

Project description:Methicillin resistant Staphylococcus aureus (MRSA) is an opportunistic pathogen chief amongst bloodstream infecting pathogens. MRSA produces an array of human specific virulence factors that may contribute to immune suppression. Here, we defined the response of primary human phagocytes to infection with MRSA using RNA-Seq. We found that the overall transcriptional response to MRSA was weak both in the number of genes and the magnitude of response. Using an ex vivo bacteremia model with fresh human blood, we found that infection with live MRSA resulted in the down-regulation of genes related to innate immune response, and cytokine and chemokine signaling. This muted transcriptional response was conserved across diverse S. aureus clones but absent in heat-killed MRSA or blood infected with live Staphylococcus epidermidis. Importantly, the muted signature was also present in patients with S. aureus bacteremia. We next identified the master regulator SaeRS and the SaeRS-regulated pore-forming toxins as key mediators of transcriptional suppression. The impaired chemokine and cytokine responses were reflected by circulating protein levels in the plasma. MRSA elicits a soluble milieu that is restrictive in the recruitment of human neutrophils compared to strains lacking saeRS. Thus, MRSA blunts the inflammatory response resulting in impaired neutrophil recruitment, which could promote the survival of S. aureus during invasive infection.

2022-07-20 | GSE193219 | GEO

The functional small RNA interactome reveals targets for the vancomycin-responsive sRNA RsaOI in vancomycin tolerant Staphylococcus aureu

Project description:Vancomycin tolerance in multidrug resistance Staphylococcus aureus is correlated with dysregulation of small RNAs although their contribution to antibiotic tolerance in poorly understood. RNA-RNA interactome profiling techniques are expanding our understanding of sRNA-mRNA interactions in bacteria; however, determining the function of these interactions for hundreds of sRNA-mRNA pairs is a major challenge. At steady-state, protein and mRNA abundances are often highly correlated and lower than expected protein abundance may indicate translational repression of an mRNA. We used label-free quantitative proteomics to examine changes in protein expression in vancomycin tolerant S. aureus strain in response to vancomycin treatment. We correlated the protein levels with gene transcript abundance and ribosome occupancy to identify sRNA-mRNA interactions that regulate mRNA translation. We used the machine learning technique self-organising maps (SOMS) to cluster genes with similar transcription and translation patterns and identified a cluster of mRNAs that appeared to be post-transcriptionally repressed. By integrating our clustering analysis with the sRNA-mRNA interactome data generated in vancomycin tolerant S. aureus by RNase III-CLASH, we identified a cluster of sRNAs that may be mediating translational repression. We have confirmed sRNA-dependant post-transcriptional repression of several mRNAs in this cluster. Two of these interactions are mediated by RsaOI, a sRNA that is highly upregulated by vancomycin, and these targets include HPr and the cell-wall autolysin Atl, with only Atl downregulated at the protein level upon vancomycin treatment. These findings suggest RsaOI coordinates carbon metabolism and cell wall turnover during vancomycin treatment

2024-03-18 | PXD049022 | Pride

RNase III-CLASH of multi-drug resistant Staphylococcus aureus reveals a regulatory mRNA 3’UTR required for intermediate vancomycin resistance

Project description:Treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections is dependant on the efficacy of last-line antibiotics like vancomycin. Vancomycin treatment failure is most commonly linked to the emergence of vancomycin-intermediate resistance in clincal isolates (termed VISA). These isolates have not acquired resistance genes but appear to accumulate a heterogenous collection of single nucleotide polymerisms that collectively alter the physiology of the cell to increase vancomycin tolerance. Cell wall thickening is common among VISA isolates and is thought to decrease vancomycin permeability. Changes in regulatory sRNA expression have been correlated with antibiotic stress responses in VISA isolates however the functions of the vast majority of these RNA regulators is unknown. Here we have used the endoribonuclease RNase III to capture RNA-RNA interactions using an RNA proximity-dependant ligation technique termed CLASH. RNase III-CLASH uncovered hundreds of sRNA-mRNA interactions in vivo allowing functional characterisation of many sRNAs for the first time. Surprisingly, we find that an mRNA encoding an unusually long 3’UTR (here termed vigR) functions as a regulatory ‘hub’ within our RNA-RNA interaction network. We demonstrate vigR promotes expression of the cell wall lytic transglycosylase encoded by isaA through a direct mRNA-mRNA interaction. Further, we find that the vigR mRNA 3’UTR is required for cell wall thickening and that deletion of the vigR 3’UTR re-sensitises VISA to vancomycin. Our results demonstrate the utility of RNase III-CLASH for identifying new regulatory RNA functions and indicate that S. aureus may use mRNA-mRNA interactions to co-ordinate gene expression much more widely than previously appreciated.

2021-09-14 | GSE158830 | GEO

Genome-wide Annotation, Identification, and Global Transcriptomic Analysis of Regulatory or Small RNA Gene Expression in Staphylococcus aureus

Project description:In Staphylococcus aureus, hundreds of small regulatory or small RNAs (sRNAs) have been identified, yet this class of molecule remains poorly understood and severely understudied. sRNA genes are typically absent from genome annotation files, and as a consequence, their existence is often overlooked, particularly in global transcriptomic studies. To facilitate improved detection and analysis of sRNAs in S. aureus, we generated updated GenBank files for three commonly used S. aureus strains (MRSA252, NCTC 8325, and USA300), in which we added annotations for >260 previously identified sRNAs. These files, the first to include genome-wide annotation of sRNAs in S. aureus, were then used as a foundation to identify novel sRNAs in the community-associated methicillin-resistant strain USA300. This analysis led to the discovery of 39 previously unidentified sRNAs. Investigating the genomic loci of the newly identified sRNAs revealed a surprising degree of inconsistency in genome anno- tation in S. aureus, which may be hindering the analysis and functional exploration of these elements. Finally, using our newly created annotation files as a reference, we perform a global analysis of sRNA gene expression in S. aureus and demonstrate that the newly identified tsr25 is the most highly upregulated sRNA in human serum. This study provides an invaluable resource to the S. aureus research community in the form of our newly generated annotation files, while at the same time presenting the first examination of differential sRNA expression in pathophysiologically relevant conditions. Four RNAseq data sets in total. Each sample was generated by pooling three independent biological replicate RNA preps

2016-01-05 | E-GEOD-74936 | biostudies-arrayexpress

The small RNA Teg41 Regulates Expression of the alpha Phenol Soluble Modulins and is Required for Virulence in Staphylococcus aureus

Project description:Small RNAs (sRNAs) remain an understudied class of regulatory molecules in bacteria. Hundreds of sRNAs have been identified in the major human pathogen Staphylococcus aureus; however, only a few have been characterized in detail. In this study we investigate the role of the sRNA Teg41 in S. aureus virulence. We demonstrate that Teg41, an sRNA divergently transcribed from the locus that encodes the cytolytic alpha phenol soluble modulin (αPSM) peptides, plays a critical role in αPSM production. Overproduction of Teg41 leads to an increase in αPSM levels and a corresponding increase in hemolytic activity from S. aureus cells and cell-free culture supernatants. We demonstrate that the increase in αPSM production is post-transcriptional, as expression of the αPSM transcript is unaltered upon Teg41 overproduction. To identify regions of Teg41 important for its function we performed an in silico RNA:RNA interaction analysis which predicted an interaction between the 3’ end of Teg41 and the αPSM transcript. Deleting a 24-nucleotide region from the S. aureus genome, corresponding to the 3’ end of Teg41, led to a 10-fold reduction in αPSM-dependent hemolytic activity and attenuation of virulence in a murine abscess model of infection. Together these results demonstrate, for the first time, post-transcriptional regulation of the αPSM peptides by an sRNA in S. aureus.

2019-01-01 | GSE108336 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data