scholarly journals A novel computational approach for genome-wide prediction of small RNAs in bacteria

2014 ◽  
Author(s):  
Lei Li ◽  
Hoi Shan Kwan
Keyword(s):  
Small Rnas ◽  
Computational Prediction ◽  
Transcriptional Regulators ◽  
Structural Features ◽  
Extensive Study ◽  
Bacterial Physiology ◽  
Genome Wide ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas ◽  
Window Approach

Small regulatory RNAs (sRNAs) are the most abundant post-transcriptional regulators in bacteria. They serve ubiquitous roles that control nearly every aspects of bacterial physiology. Identification of important features from sRNAs sequences will guide the computational prediction of new sRNA sequences for a better understanding of the pervasive sRNA-mediated regulation in bacteria. In this study, we have performed systematic analyses of many sequence and structural features that are possibly related to sRNA properties and identified a subset of significant features that effectively discriminate sRNAs sequences from random sequences. we then used a neural network model that integrated these subfeatures on unlabeled testing datasets, and it had achieved a 92.2% recall and 89.8% specificity. Finally, we applied this prediction model for genome-wide identification of sRNAs-encoded genes using a sliding-window approach. We recovered multiple known sRNAs and hundreds of predicted new sRNAs. These candidate novel sRNAs deserve extensive study to better understand the sRNA-mediated regulatory network in bacteria.

Mechanisms by Which Small RNAs Affect Bacterial Activity

2019 ◽  
Vol 98 (12) ◽  
pp. 1315-1323
Author(s):  
L. Lei ◽  
Y. Yang ◽  
Y. Yang ◽  
S. Wu ◽  
X. Ma ◽  
...  
Keyword(s):  
Stress Responses ◽  
Small Rnas ◽  
Environmental Changes ◽  
Expression Profiles ◽  
Bacterial Flora ◽  
Oral Disease ◽  
Bacterial Gene ◽  
Bacterial Physiology ◽  
Cellular Processes ◽  
Regulatory Rnas

The oral cavity contains a distinct habitat that supports diverse bacterial flora. Recent observations have provided additional evidence that sRNAs are key regulators of bacterial physiology and pathogenesis. These sRNAs have been divided into 5 functional groups: cis-encoded RNAs, trans-encoded RNAs, RNA regulators of protein activity, bacterial CRISPR (clustered regularly interspaced short palindromic repeat) RNAs, and a novel category of miRNA-size small RNAs (msRNAs). In this review, we discuss a critical group of key commensal and opportunistic oral pathogens. In general, supragingival bacterial sRNAs function synergistically to fine-tune the regulation of cellular processes and stress responses in adaptation to environmental changes. Particularly in the cariogenic bacteria Streptococcus mutans, both the antisense vicR RNA and msRNA1657 can impede the metabolism of bacterial exopolysaccharides, prevent biofilm formation, and suppress its cariogenicity. In Enterococcus faecalis, selected sRNAs control the expression of proteins involved in diverse cellular processes and stress responses. In subgingival plaques, sRNAs from periodontal pathogens can function as novel bacterial signaling molecules that mediate bacterial-human interactions in periodontal homeostasis. In Porphyromonas gingivalis, the expression profiles of putative sRNA101 and sRNA42 were found to respond to hemin availability after hemin starvation. Regarding Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), a major periodontal pathogen associated with aggressive periodontitis, the predicted sRNAs interact with several virulence genes, including those encoding leukotoxin and cytolethal distending toxin. Furthermore, in clinical isolates, these associated RNAs could be explored not only as potential biomarkers for oral disease monitoring but also as alternative types of regulators for drug design. Thus, this emerging subspecialty of bacterial regulatory RNAs could reshape our understanding of bacterial gene regulation from their key roles of endogenous regulatory RNAs to their activities in pathologic processes.

scholarly journals Computational prediction of nonenzymatic RNA degradation patterns

2017 ◽  
Vol 63 (4) ◽  
Author(s):  
Agnieszka Rybarczyk ◽  
Paulina Jackowiak ◽  
Marek Figlerowicz ◽  
Jacek Blazewicz
Keyword(s):  
Regulation Of Gene Expression ◽  
Computational Prediction ◽  
Rna Degradation ◽  
Branch And Cut ◽  
Structural Factors ◽  
Rna Molecules ◽  
Small Regulatory Rnas ◽  
Rna Fragments ◽  
Regulatory Rnas

Since the beginning of XXI century, the increasing interest in the research of ribonucleic acids has been observed in response to a surprising discovery of the role that RNA molecules play in the biological systems. It was demonstrated that they do not only take part in the protein synthesis (mRNA, rRNA, tRNA) but also are involved in the regulation of gene expression. Several classes of small regulatory RNAs have been discovered (e.g. microRNA, small interfering RNA, piwiRNA). Most of them are excised from specific double-stranded RNA precursors by enzymes that belong to the RNaseIII family (Drosha, Dicer or Dicer-like proteins). More recently, it has been shown that small regulatory RNAs are also generated as stable intermediates of RNA degradation (so called RNA fragments originating from tRNA, snRNA, snoRNA etc.). Unfortunately, the mechanisms underlying biogenesis of the RNA fragments remain unclear. It is thought that several factors may be involved in the formation of the RNA fragments. The most important are specific RNases, RNA-protein interactions and RNA structure.  In this work, we focus on RNA primary and secondary structures as factors influencing RNA stability and consequently the pattern of RNA fragmentation. Earlier, we identified major structural factors affecting non-enzymatic RNA degradation. Now based on these data we developed a new branch-and-cut algorithm that is able to predict the products of large RNA molecules hydrolysis in vitro. We also present the experimental data that verify the results generated using this algorithm.

scholarly journals Two GacA-Dependent Small RNAs Modulate the Quorum-Sensing Response in Pseudomonas aeruginosa

2006 ◽  
Vol 188 (16) ◽  
pp. 6026-6033 ◽  
Author(s):  
Elisabeth Kay ◽  
Bérénice Humair ◽  
Valérie Dénervaud ◽  
Kathrin Riedel ◽  
Stéphanie Spahr ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Small Rnas ◽  
Homoserine Lactone ◽  
Two Component System ◽  
Bond Forming ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas ◽  
Chitin Binding Protein ◽  
Biofilm Development

ABSTRACT In Pseudomonas aeruginosa, the GacS/GacA two-component system positively controls the quorum-sensing machinery and the expression of extracellular products via two small regulatory RNAs, RsmY and RsmZ. An rsmY rsmZ double mutant and a gacA mutant were similarly impaired in the synthesis of the quorum-sensing signal N-butanoyl-homoserine lactone, the disulfide bond-forming enzyme DsbA, and the exoproducts hydrogen cyanide, pyocyanin, elastase, chitinase (ChiC), and chitin-binding protein (CbpD). Both mutants showed increased swarming ability, azurin release, and early biofilm development.

scholarly journals Genome wide analysis of heat responsive microRNAs in banana during acquired thermo tolerance

2018 ◽  
Vol 13 (1) ◽  
pp. 61-71 ◽  
Author(s):  
S M Vidya ◽  
K V Ravishankar ◽  
R H Laxman
Keyword(s):  
Expression Patterns ◽  
Negative Relationship ◽  
Genome Wide Analysis ◽  
Qpcr Analysis ◽  
Genome Wide ◽  
Small Regulatory Rnas ◽  
Protective Genes ◽  
Three Stages ◽  
Regulatory Rnas ◽  
Lower Expression

MicroRNAs are a class of small regulatory RNAs in plants, which play vital roles during various abiotic and abiotic stress conditions including plant processes. In this present study, we examined the expression of miRNAs and their predicted target expression levels during heat stress in banana. Out of 235 miRNA found in Musa, 40 miRNA showed homology to heat responsive miRNAs from other plants. Further, 14 targets for miRNA were predicted that are potentially regulated by their cognate miRNAs and were monitored under three stages of stress viz, induction, induction + lethal alone using qPCR analysis. The results suggest that generally, there is a negative relationship in the expression patterns of miRNA and their predicted cognate targets - HSP70, HSP90, SAP, DNAj genes. These were highly up regulated and their respective miRNAs showed lower expression. This is the first report in banana, which demonstrated that during induction stress, various thermo-protective genes are activated at initial stages of stress to achieve thermotolerance through altered miRNA expression. The results will help in broadening our understanding acquired thermotolerance and their regulation by miRNAs in plants.

scholarly journals Assembling the Current Pieces: The Puzzle of RNA-Mediated Regulation in Staphylococcus aureus

2021 ◽  
Vol 12 ◽  
Author(s):  
Laura Barrientos ◽  
Noémie Mercier ◽  
David Lalaouna ◽  
Isabelle Caldelari
Keyword(s):  
Staphylococcus Aureus ◽  
Stress Responses ◽  
Regulatory Networks ◽  
High Throughput Sequencing ◽  
Bacterial Physiology ◽  
Sequencing Technologies ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas ◽  
Infection Processes

The success of the major opportunistic human Staphylococcus aureus relies on the production of numerous virulence factors, which allow rapid colonization and dissemination in any tissues. Indeed, regulation of its virulence is multifactorial, and based on the production of transcriptional factors, two-component systems (TCS) and small regulatory RNAs (sRNAs). Advances in high-throughput sequencing technologies have unveiled the existence of hundreds of potential RNAs with regulatory functions, but only a fraction of which have been validated in vivo. These discoveries have modified our thinking and understanding of bacterial physiology and virulence fitness by placing sRNAs, alongside transcriptional regulators, at the center of complex and intertwined regulatory networks that allow S. aureus to rapidly adapt to the environmental cues present at infection sites. In this review, we describe the recently acquired knowledge of characterized regulatory RNAs in S. aureus that are associated with metal starvation, nutrient availability, stress responses and virulence. These findings highlight the importance of sRNAs for the comprehension of S. aureus infection processes while raising questions about the interplay between these key regulators and the pathways they control.

scholarly journals A Genome-Wide Identification Analysis of Small Regulatory RNAs in Mycobacterium tuberculosis by RNA-Seq and Conservation Analysis

PLoS ONE ◽  
2012 ◽  
Vol 7 (3) ◽  
pp. e32723 ◽  
Author(s):  
Danilo Pellin ◽  
Paolo Miotto ◽  
Alessandro Ambrosi ◽  
Daniela Maria Cirillo ◽  
Clelia Di Serio
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Rna Seq ◽  
Conservation Analysis ◽  
Genome Wide ◽  
A Genome ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas ◽  
Identification Analysis

scholarly journals Genome-Wide Detection of Small Regulatory RNAs in Deep-Sea Bacterium Shewanella piezotolerans WP3

2017 ◽  
Vol 8 ◽  
Author(s):  
Muhammad Z. Nawaz ◽  
Huahua Jian ◽  
Ying He ◽  
Lei Xiong ◽  
Xiang Xiao ◽  
...  
Keyword(s):  
Deep Sea ◽  
Genome Wide ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas

scholarly journals Small Toxic Proteins and the Antisense RNAs That Repress Them

2008 ◽  
Vol 72 (4) ◽  
pp. 579-589 ◽  
Author(s):  
Elizabeth M. Fozo ◽  
Matthew R. Hemm ◽  
Gisela Storz
Keyword(s):  
Amino Acids ◽  
Small Rna ◽  
Small Rnas ◽  
Short Length ◽  
Type I ◽  
Practical Applications ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas ◽  
Rna Genes ◽  
Toxic Proteins

SUMMARY There has been a great expansion in the number of small regulatory RNAs identified in bacteria. Some of these small RNAs repress the synthesis of potentially toxic proteins. Generally the toxin proteins are hydrophobic and less than 60 amino acids in length, and the corresponding antitoxin small RNA genes are antisense to the toxin genes or share long stretches of complementarity with the target mRNAs. Given their short length, only a limited number of these type I toxin-antitoxin loci have been identified, but it is predicted that many remain to be found. Already their characterization has given insights into regulation by small RNAs, has suggested functions for the small toxic proteins at the cell membrane, and has led to practical applications for some of the type I toxin-antitoxin loci.

scholarly journals Compensatory sequence variation between trans-species small RNAs and their target sites

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Nathan R Johnson ◽  
Claude W dePamphilis ◽  
Michael J Axtell
Keyword(s):  
Small Rnas ◽  
Synonymous Site ◽  
Protein Coding ◽  
Coding Regions ◽  
Target Sites ◽  
Site Variation ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas ◽  
Multiple Species ◽  
Multiple Variants

Trans-species small regulatory RNAs (sRNAs) are delivered to host plants from diverse pathogens and parasites and can target host mRNAs. How trans-species sRNAs can be effective on diverse hosts has been unclear. Multiple species of the parasitic plant Cuscuta produce trans-species sRNAs that collectively target many host mRNAs. Confirmed target sites are nearly always in highly conserved, protein-coding regions of host mRNAs. Cuscuta trans-species sRNAs can be grouped into superfamilies that have variation in a three-nucleotide period. These variants compensate for synonymous-site variation in host mRNAs. By targeting host mRNAs at highly conserved protein-coding sites, and simultaneously expressing multiple variants to cover synonymous-site variation, Cuscuta trans-species sRNAs may be able to successfully target multiple homologous mRNAs from diverse hosts.

scholarly journals RNA-dependent RNA polymerases in the black-legged tick produce Argonaute-dependent small RNAs and regulate genes

2021 ◽  
Author(s):  
Canran Feng ◽  
Kyosuke Torimaru ◽  
Mandy Yu Theng Lim ◽  
Li-Ling Chak ◽  
Kosuke Tsuji ◽  
...  
Keyword(s):  
Small Rnas ◽  
Rna Polymerase Iii ◽  
Feedback Regulation ◽  
Rna Polymerases ◽  
Effector Proteins ◽  
Protein Coding ◽  
C Elegans ◽  
Animal Pathogens ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas

Small regulatory RNAs (sRNAs) are involved in anti-viral defense and gene regulation. Although RNA-dependent RNA Polymerases (RdRPs) are known to produce sRNA in nematodes, plants and fungi, whether they play roles in sRNA biogenesis in other animals remains controversial. In this study, we study sRNAs in the ISE6 cell line, which is derived from the black-legged tick, an important vector of human and animal pathogens. We identify abundant classes of ~22nt sRNAs that require specific combinations of RdRPs and sRNA effector proteins (Argonautes or AGOs). RdRP-dependent sRNAs are mainly derived from sense and antisense strands of RNA polymerase III-transcribed genes and repetitive elements. Unlike C. elegans sRNA pathways, 5′-tri-phosphorylated sRNAs are not detected, suggesting that the tick pathways are distinct from the pathways known in worms. Knockdown of one of the RdRPs unexpectedly results in downregulation of a subset of viral transcripts, in contrast to their upregulation by AGO knockdown. Furthermore, we show that knockdown of AGO/RdRP causes misregulation of protein-coding genes including RNAi-related genes, suggesting feedback regulation. Luciferase assays demonstrate that one of the RdRP-regulated genes, the MEK1 ortholog IscDsor1 is regulated through its 3′UTR, where a putative sRNA target site resides. These results provide evidence that arachnid RdRPs are important sRNA biogenesis factors, and the discovery of novel pathways underscores the importance of characterizing sRNA biogenesis in various organisms to understand virus-vector interactions and to exploit RNAi for pest control.

Sign in / Sign up

Export Citation Format

Share Document