scholarly journals Insights into the Function of Regulatory RNAs in Bacteria and Archaea

2021 ◽  
Vol 1 (3) ◽  
pp. 403-423
Author(s):  
Elahe Soltani-Fard ◽  
Sina Taghvimi ◽  
Zahra Abedi Kichi ◽  
Christian Weber ◽  
Zahra Shabaninejad ◽  
...  
Keyword(s):  
Defense Mechanism ◽  
Regulation Of Gene Expression ◽  
Rna Molecules ◽  
Physiological Processes ◽  
Wide Range ◽  
Phage Dna ◽  
Small Molecule Ligands ◽  
Small Regulatory Rnas ◽  
Short Palindromic Repeat ◽  
Regulatory Rnas

Non-coding RNAs (ncRNAs) are functional RNA molecules that comprise about 80% of both mammals and prokaryotes genomes. Recent studies have identified a large number of small regulatory RNAs in Escherichia coli and other bacteria. In prokaryotes, RNA regulators are a diverse group of molecules that modulate a wide range of physiological responses through a variety of mechanisms. Similar to eukaryotes, bacterial microRNAs are an important class of ncRNAs that play an important role in the development and secretion of proteins and in the regulation of gene expression. Similarly, riboswitches are cis-regulatory structured RNA elements capable of directly controlling the expression of downstream genes in response to small molecule ligands. As a result, riboswitches detect and respond to the availability of various metabolic changes within cells. The most extensive and most widely studied set of small RNA regulators act through base pairing with RNAs. These types of RNAs are vital for prokaryotic life, activating or suppressing important physiological processes by modifying transcription or translation. The majority of these small RNAs control responses to changes in environmental conditions. Finally, clustered regularly interspaced short palindromic repeat (CRISPR) RNAs, a newly discovered RNA regulator group, contains short regions of homology to bacteriophage and plasmid sequences that bacteria use to splice phage DNA as a defense mechanism. The detailed mechanism is still unknown but devoted to target homologous foreign DNAs. Here, we review the known mechanisms and roles of non-coding regulatory RNAs, with particular attention to riboswitches and their functions, briefly introducing translational applications of CRISPR RNAs in mammals.

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 Regulatory RNAs in Bacillus subtilis: a Gram-Positive Perspective on Bacterial RNA-Mediated Regulation of Gene Expression

2016 ◽  
Vol 80 (4) ◽  
pp. 1029-1057 ◽  
Author(s):  
Ruben A. T. Mars ◽  
Pierre Nicolas ◽  
Emma L. Denham ◽  
Jan Maarten van Dijl
Keyword(s):  
Gene Expression ◽  
Bacillus Subtilis ◽  
Regulation Of Gene Expression ◽  
Regulatory Rna ◽  
Gram Positive ◽  
Content Type ◽  
Rna Molecules ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas ◽  
The Stability

SUMMARYBacteria can employ widely diverse RNA molecules to regulate their gene expression. Such molecules includetrans-acting small regulatory RNAs, antisense RNAs, and a variety of transcriptional attenuation mechanisms in the 5′ untranslated region. Thus far, most regulatory RNA research has focused on Gram-negative bacteria, such asEscherichia coliandSalmonella. Hence, there is uncertainty about whether the resulting insights can be extrapolated directly to other bacteria, such as the Gram-positive soil bacteriumBacillus subtilis. A recent study identified 1,583 putative regulatory RNAs inB. subtilis, whose expression was assessed across 104 conditions. Here, we review the current understanding of RNA-based regulation inB. subtilis, and we categorize the newly identified putative regulatory RNAs on the basis of their conservation in other bacilli and the stability of their predicted secondary structures. Our present evaluation of the publicly available data indicates that RNA-mediated gene regulation inB. subtilismostly involves elements at the 5′ ends of mRNA molecules. These can include 5′ secondary structure elements and metabolite-, tRNA-, or protein-binding sites. Importantly, sense-independent segments are identified as the most conserved and structured potential regulatory RNAs inB. subtilis. Altogether, the present survey provides many leads for the identification of new regulatory RNA functions inB. subtilis.

MiR-302: The Multifunctional MicroRNA

2019 ◽  
Vol 3 (1) ◽  
pp. 01-02
Author(s):  
Shao Ying
Keyword(s):  
Protein Translation ◽  
Mature Mirnas ◽  
Mirna Precursor ◽  
Regulate Gene Expression ◽  
Cellular Processes ◽  
Target Mrnas ◽  
Complementary Sequences ◽  
Wide Range ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas

MicroRNAs (miRNAs) are short single-stranded noncoding RNAs (20- to 25-nucleotide (nt) long) representing a class of small regulatory RNAs. By inhibiting the translation of target mRNAs, miRNAs regulate gene expression posttranscriptionally and thus play an important role in a wide range of cellular processes. Currently, there are two known types of miRNAs: intergenic and intronic miRNAs. Biogenesis of an intergenic miRNA starts with the synthesis of a primary miRNA transcript (pri-miRNA) catalyzed by types-II or -III RNA polymerase (Pol-II/III). Pri-miRNAs are processed in the nucleus by the ribonuclease Drosha into a miRNA precursor (pre-miRNA) approximately 60-nt in length. After being transported into the cytoplasm, these pre-miRNAs are further processed into mature and functional miRNAs by the cytoplasmic ribonuclease Dicer. Mature miRNAs then associate with a number of proteins to form the RNA-induced silencing complex (RISC) that bind with target mRNAs having total or partial complementary sequences to the miRNAs and initiate the inhibition of subsequent protein translation via RNA interference (RNAi).

scholarly journals The Emerging Role of MicroRNAs in Bone Diseases and Their Therapeutic Potential

Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 211
Author(s):  
Luis Alberto Bravo Vázquez ◽  
Mariana Yunuen Moreno Becerril ◽  
Erick Octavio Mora Hernández ◽  
Gabriela García de León Carmona ◽  
María Emilia Aguirre Padilla ◽  
...  
Keyword(s):  
Bone Growth ◽  
Bone Cells ◽  
Therapeutic Potential ◽  
Regulation Of Gene Expression ◽  
Bone Diseases ◽  
Osteosarcoma Cell ◽  
Main Function ◽  
Altered Expression ◽  
Rna Molecules ◽  
Wide Range

MicroRNAs (miRNAs) are a class of small (20–24 nucleotides), highly conserved, non-coding RNA molecules whose main function is the post-transcriptional regulation of gene expression through sequence-specific manners, such as mRNA degradation or translational repression. Since these key regulatory molecules are implicated in several biological processes, their altered expression affects the preservation of cellular homeostasis and leads to the development of a wide range of pathologies. Over the last few years, relevant investigations have elucidated that miRNAs participate in different stages of bone growth and development. Moreover, the abnormal expression of these RNA molecules in bone cells and tissues has been significantly associated with the progression of numerous bone diseases, including osteoporosis, osteosarcoma, osteonecrosis and bone metastasis, among others. In fact, miRNAs regulate multiple pathological mechanisms, including altering either osteogenic or osteoblast differentiation, metastasis, osteosarcoma cell proliferation, and bone loss. Therefore, in this present review, aiming to impulse the research arena of the biological implications of miRNA transcriptome in bone diseases and to explore their potentiality as a theragnostic target, we summarize the recent findings associated with the clinical significance of miRNAs in these ailments.

scholarly journals The Etiological Agent of Lyme Disease, Borrelia burgdorferi, Appears To Contain Only a Few Small RNA Molecules

2004 ◽  
Vol 186 (24) ◽  
pp. 8472-8477 ◽  
Author(s):  
Yngve Östberg ◽  
Ignas Bunikis ◽  
Sven Bergström ◽  
Jörgen Johansson
Keyword(s):  
Borrelia Burgdorferi ◽  
Small Rna ◽  
Rna Binding ◽  
Rna Binding Protein ◽  
Rnase E ◽  
Regulatory Pathways ◽  
Rna Molecules ◽  
Small Regulatory Rnas ◽  
Regulatory Rnas

ABSTRACT Small regulatory RNAs (sRNAs) have recently been shown to be the main controllers of several regulatory pathways. The function of sRNAs depends in many cases on the RNA-binding protein Hfq, especially for sRNAs with an antisense function. In this study, the genome of Borrelia burgdorferi was subjected to different searches for sRNAs, including direct homology and comparative genomics searches and ortholog- and annotation-based search strategies. Two new sRNAs were found, one of which showed complementarity to the rpoS region, which it possibly controls by an antisense mechanism. The role of the other sRNA is unknown, although observed complementarities against particular mRNA sequences suggest an antisense mechanism. We suggest that the low level of sRNAs observed in B. burgdorferi is at least partly due to the presumed lack of both functional Hfq protein and RNase E activity.

scholarly journals The Role of Micrornas in Genome Response to Plant–Lepidoptera Interaction

Plants ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 529
Author(s):  
Katarína Ražná ◽  
Ľudovít Cagáň
Keyword(s):  
Rna Interference ◽  
Immune Responses ◽  
Host Resistance ◽  
Defense Mechanism ◽  
Plant Protection ◽  
Regulation Of Gene Expression ◽  
Basic Principles ◽  
Double Stranded Rna ◽  
Rna Molecules

RNA interference is a known phenomenon of plant immune responses, involving the regulation of gene expression. The key components triggering the silencing of targeted sequences are double-stranded RNA molecules. The regulation of host–pathogen interactions is controlled by miRNA molecules, which regulate the expression of host resistance genes or the genes of the pathogen. The review focused on basic principles of RNA interference as a gene-silencing-based defense mechanism and the role of miRNA molecules in insect genomes. RNA interference as a tool for plant protection management is discussed. The review summarizes current miRNA-based biotechnology approaches for plant protection management.

Genes Expressed in Ascochyta raftiei-Inoculated Chickpea Plants and Elicited Cell Cultures as Detected by Differential cDNA-Hybridization

2000 ◽  
Vol 55 (1-2) ◽  
pp. 44-54 ◽  
Author(s):  
Yuki Ichinose ◽  
Karin Tiemann ◽  
Claudia Schwenger-Erger ◽  
Kazuhiro Toyoda ◽  
Frauke Hein ◽  
...  
Keyword(s):  
Cell Cultures ◽  
Defense Mechanism ◽  
Regulation Of Gene Expression ◽  
Gene Activation ◽  
Defense Responses ◽  
Cdna Clones ◽  
Primary Metabolism ◽  
Plant Defense Responses ◽  
Wide Range ◽  
Cdna Hybridization

Abstract In response to the exogenous application of elicitors and attempted invasion by pathogens, plants exhibit a wide range of defense reactions. To understand the defense mechanism s at the level of gene activation and deactivation, differential screenings were perform ed to isolate cDNA clones which are differentially expressed in pathogen-inoculated resistant chickpea plants and elicitor-treated cell cultures. A plenty of genes were isolated and arranged in 5 groups, namely defense-related pathways, signal transduction pathways, regulation of gene expression, catabolic pathways and primary metabolism . Most of these genes were activated although several genes were also found to be suppressed. We discuss the plausible functions of cDNA products in plant defense responses. The cDNA s provide a variety of tools to investigate m olecular mechanisms of defense responses and clearly reflect the massive genomic and metabolic changes which occur during manifestation of antimicrobial defense.

scholarly journals The role of microRNAs in the legume–Rhizobium nitrogen-fixing symbiosis

2020 ◽  
Vol 71 (5) ◽  
pp. 1668-1680 ◽  
Author(s):  
Nhung T Hoang ◽  
Katalin Tóth ◽  
Gary Stacey
Keyword(s):  
Vascular System ◽  
Regulation Of Gene Expression ◽  
Lotus Japonicus ◽  
Nodule Formation ◽  
Nitrogen Fixing ◽  
Rna Molecules ◽  
Physiological Processes ◽  
Leaf Tissues ◽  
And Function

Abstract Under nitrogen starvation, most legume plants form a nitrogen-fixing symbiosis with Rhizobium bacteria. The bacteria induce the formation of a novel organ called the nodule in which rhizobia reside as intracellular symbionts and convert atmospheric nitrogen into ammonia. During this symbiosis, miRNAs are essential for coordinating the various plant processes required for nodule formation and function. miRNAs are non-coding, endogenous RNA molecules, typically 20–24 nucleotides long, that negatively regulate the expression of their target mRNAs. Some miRNAs can move systemically within plant tissues through the vascular system, which mediates, for example, communication between the stem/leaf tissues and the roots. In this review, we summarize the growing number of miRNAs that function during legume nodulation focusing on two model legumes, Lotus japonicus and Medicago truncatula, and two important legume crops, soybean (Glycine max) and common bean (Phaseolus vulgaris). This regulation impacts a variety of physiological processes including hormone signaling and spatial regulation of gene expression. The role of mobile miRNAs in regulating legume nodule number is also highlighted.

Plant microRNA: Methods of studying and the role in the development of symbiosis with beneFicial microorganisms

Biomics ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 166-175
Author(s):  
Е.А. Зорин ◽  
О.А. Кулаева ◽  
В.А. Жуков
Keyword(s):  
Gene Expression ◽  
Statistical Tests ◽  
Regulation Of Gene Expression ◽  
Functional Enrichment ◽  
Data Quality Control ◽  
Sequencing Data ◽  
Experimental Conditions ◽  
Rna Molecules ◽  
Wide Range ◽  
Microrna Sequencing

MicroRNAs are small non-coding RNA molecules that act as post-transcriptional regulators of gene expression due to rather strict complementarity to their mRNA and have a length of 20-24 nucleotides. Plant microRNAs control a wide range of physiological processes, including nutrition, growth, resistance reactions and interaction with other organisms, via modulation of the expression of transcription factors, stress-induced proteins, hormone biosynthesis enzymes, and other genes. Legumes are able to form mutualistic symbioses simultaneously with nitrogen-fixing bacteria and arbuscular mycorrhiza. Both the early and late stages of these symbiosis are regulated by complex genetic mechanisms. As it has become known in recent years, one of these mechanisms is the regulation of gene expression by microRNA. The study of microRNAs is carried out by various methods, but over the past decade, next-generation sequencing (NGS) technologies have become the most popular approach in this field. NGS is used to identify conservative and novel microRNAs in the genomes of various organisms (both model and non-model), as well as to study the functioning of microRNAs in various experimental conditions with the additional use of transcriptome and degradome sequencing data. The article describes the main stages of working with microRNA sequencing data: quality control of reads (with a list of programs required at this stage), identification of conservative and novel microRNAs using miRDeep2 tool, search for targets of identified microRNAs using PAREsnip2, functional annotation of targets and the use of statistical tests for the analysis of functional enrichment, which facilitates the interpretation of the data obtained and allows us to make assumptions about the biological consequences of the activity of identified microRNAs in the object under study. This information may be useful for researchers who deal with microRNAs in silico for the first time or want to save time and resources on searching and analyzing information about the tools needed to work with microRNA sequencing data.

scholarly journals Physiological roles of small RNA molecules

Microbiology ◽  
2014 ◽  
Vol 160 (6) ◽  
pp. 1007-1019 ◽  
Author(s):  
Charlotte Michaux ◽  
Nicolas Verneuil ◽  
Axel Hartke ◽  
Jean-Christophe Giard
Keyword(s):  
Environmental Changes ◽  
Growth Conditions ◽  
Culture Conditions ◽  
Rna Molecules ◽  
Physiological Processes ◽  
Sensing Systems ◽  
Genes Encoding ◽  
Regulation Mechanisms ◽  
Regulatory Rnas ◽  
Metal Sensing

Unlike proteins, RNA molecules have emerged lately as key players in regulation in bacteria. Most reviews hitherto focused on the experimental and/or in silico methods used to identify genes encoding small RNAs (sRNAs) or on the diverse mechanisms of these RNA regulators to modulate expression of their targets. However, less is known about their biological functions and their implications in various physiological responses. This review aims to compile what is known presently about the diverse roles of sRNA transcripts in the regulation of metabolic processes, in different growth conditions, in adaptation to stress and in microbial pathogenesis. Several recent studies revealed that sRNA molecules are implicated in carbon metabolism and transport, amino acid metabolism or metal sensing. Moreover, regulatory RNAs participate in cellular adaptation to environmental changes, e.g. through quorum sensing systems or development of biofilms, and analyses of several sRNAs under various physiological stresses and culture conditions have already been performed. In addition, recent experiments performed with Gram-positive and Gram-negative pathogens showed that regulatory RNAs play important roles in microbial virulence and during infection. The combined results show the diversity of regulation mechanisms and physiological processes in which sRNA molecules are key actors.

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