Sibling rivalry: related bacterial small RNAs and their redundant and non-redundant roles.
Small RNA molecules (sRNAs) are now recognized as key regulators controlling bacterial gene expression, as sRNAs provide a quick and efficient means of positively or negatively altering the expression of specific genes. To date, numerous sRNAs have been identified and characterized in a myriad of bacterial species, but more recently, a theme in bacterial sRNAs has emerged: the presence of more than one highly related sRNAs produced by a given bacterium, here termed sibling sRNAs. Sibling sRNAs are those that are highly similar at the nucleotide level, and while it might be expected that sibling sRNAs exert identical regulatory functions on the expression of target genes based on their high degree of relatedness, emerging evidence is demonstrating that this is not always the case. Indeed, there are several examples of bacterial sibling sRNAs with non-redundant regulatory functions, but there are also instances of apparent regulatory redundancy between sibling sRNAs. This review provides a comprehensive overview of the current knowledge of bacterial sibling sRNAs, and also discusses important questions about the significance and evolutionary implications of this emerging class of regulators.
Department of Biomedical Sciences and Pathobiology, Center for Molecular Medicine and Infectious Diseases, VA-MD Regional College of Veterinary Medicine, Virginia Tech Blacksburg, VA, USA.
Clayton C
CC
Caswell
Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland Baltimore, MD, USA ; Department of Microbiology and Immunology, School of Medicine, University of Maryland Baltimore, MD, USA.
Amanda G
AG
Oglesby-Sherrouse
Department of Biomedical Sciences, Ohio University Heritage College of Osteopathic Medicine Athens, OH, USA.
Erin R
ER
Murphy
D001419:Bacteria / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D019143:Evolution, Molecular; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D012329:RNA, Bacterial / Q000235:genetics* / Q000378:metabolism; D014774:Virulence / Q000235:genetics
D012329:RNA, Bacterial
bacterial small RNA; regulation; ribo-regulation; sRNA; sibling sRNA