Dataset Information

Expression of the sarA family of genes in different strains of Staphylococcus aureus.

ABSTRACT: Expression of genes involved in the pathogenesis of Staphylococcus aureus is controlled by global regulatory loci, including two-component regulatory systems and transcriptional regulators. The staphylococcal-specific SarA family of transcription regulators control large numbers of target genes involved in virulence, autolysis, biofilm formation, stress responses and metabolic processes, and are recognized as potential therapeutic targets. Expression of some of these important regulators has been examined, mostly in laboratory strains, while the pattern of expression of these genes in other strains, especially clinical isolates, is largely unknown. In this report, a comparative analysis of 10 sarA-family genes was conducted in six different S. aureus strains, including two laboratory (RN6390, SH1000) and four clinical (MW2, Newman, COL and UAMS-1) strains, by Northern and Western blot analyses. Transcription of most of the sarA-family genes showed a strong growth phase-dependence in all strains tested. Among these genes, no difference was observed in expression of the sarA, sarV, sarT and sarU genes, while a major difference was observed in expression of the sarX gene only in strain RN6390. Expression of mgrA, rot, sarZ, sarR and sarS was observed in all strains, but the level of expression varied from strain to strain.

SUBMITTER: Ballal A

PROVIDER: S-EPMC2888119 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Expression of the sarA family of genes in different strains of Staphylococcus aureus.

Ballal Anand A Manna Adhar C AC

Microbiology (Reading, England) 20090423 Pt 7

Expression of genes involved in the pathogenesis of Staphylococcus aureus is controlled by global regulatory loci, including two-component regulatory systems and transcriptional regulators. The staphylococcal-specific SarA family of transcription regulators control large numbers of target genes involved in virulence, autolysis, biofilm formation, stress responses and metabolic processes, and are recognized as potential therapeutic targets. Expression of some of these important regulators has bee ...[more]

PMID: 19389785

Similar Datasets

Project description:SarA, a transcriptional regulator of Staphylococcus aureus, is a major global regulatory system that coordinates the expression of target genes involved in its pathogenicity. Various studies have identified a large number of SarA target genes, but an in-depth characterization of the sarA regulon, including small regulatory RNAs (sRNAs), has not yet been done. In this study, we utilized transcriptome sequencing (RNA-Seq) and chromatin immunoprecipitation sequencing (ChIP-Seq) to determine a comprehensive list of SarA-regulated targets, including both mRNAs and sRNAs. RNA-Seq analysis indicated 390 mRNAs and 51 sRNAs differentially expressed in a ΔsarA mutant, while ChIP-Seq revealed 354 mRNAs and 55 sRNA targets in the S. aureus genome. We confirmed the authenticity of several novel SarA targets by Northern blotting and electrophoretic mobility shift assays. Among them, we characterized repression of sprG2, a gene that encodes the toxin of a type I toxin-antitoxin system, indicating a multilayer lockdown of toxin expression by both SarA and its cognate antitoxin, SprF2. Finally, a novel SarA consensus DNA binding sequence was generated using the upstream promoter sequences of 15 novel SarA-regulated sRNA targets. A genome-wide scan with a deduced SarA motif enabled the discovery of new potential SarA target genes which were not identified in our RNA-Seq and ChIP-Seq analyses. The strength of this new consensus was confirmed with one predicted sRNA target. The RNA-Seq and ChIP-Seq combinatory analysis gives a snapshot of the regulation, whereas bioinformatic analysis reveals a permanent view of targets based on sequence. Altogether these experimental and in silico methodologies are effective to characterize transcriptional factor (TF) regulons and functions. IMPORTANCE Staphylococcus aureus, a commensal and opportunist pathogen, is responsible for a large number of human and animal infections, from benign to severe. Gene expression adaptation during infection requires a complex network of regulators, including transcriptional factors (TF) and sRNAs. TF SarA influences virulence, metabolism, biofilm formation, and resistance to some antibiotics. SarA directly regulates expression of around 20 mRNAs and a few sRNAs. Here, we combined high-throughput expression screening methods combined with binding assays and bioinformatics for an in-depth investigation of the SarA regulon. This combinatory approach allowed the identification of 85 unprecedented mRNAs and sRNAs targets, with at least 14 being primary. Among novel SarA direct targets, we characterized repression of sprG2, a gene that encodes the toxin of a toxin-antitoxin system, indicating a multilayer lockdown of toxin expression by both SarA and its cognate antitoxin, SprF2.

Dataset Information

Expression of the sarA family of genes in different strains of Staphylococcus aureus.

Publications

Expression of the sarA family of genes in different strains of Staphylococcus aureus.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets