title: sRNA-Xcc1, an integron-encoded transposon- and plasmid-transferred trans-acting sRNA, is under the positive control of the key virulence regulators HrpG and HrpX of Xanthomonas campestris pathovar campestris.
abstract: sRNA-Xcc1 is a trans-acting sRNA recently identified from the plant pathogenic bacterium Xanthomonas campestris pathovar campestris (Xcc). Here, the phylogenetic distribution, predicted secondary structure and regulation of expression of sRNA-Xcc1 were analyzed. The analysis showed (1) a total 81 sRNA-Xcc1 homologs that are found in some bacterial strains that are taxonomically unrelated, belonging to the α-, β-, γ- and δ-proteobacteria (2) that some sRNA-Xcc1 homologs are located in a plasmid-borne transposon or near a transposase coding gene, (3) that sRNA-Xcc1 is encoded by a integron gene cassette in Xcc and sRNA-Xcc1 homologs occur in integron gene cassettes of some uncultured bacteria and (4) that sRNA-Xcc1 homologs have a highly conserved sequence motif and a stable consensus secondary structure. These findings strongly support the idea that sRNA-Xcc1 represents a novel family of sRNAs which may be originally captured by integrons from natural environments and then spread among different bacterial species via horizontal gene transfer, possibly by means of transposons and plasmids. The expression analysis results demonstrated that the transcription of sRNA-Xcc1 is under the positive control of the key virulence regulators HrpG and HrpX, indicating that sRNA-Xcc1 may be involved in the virulence regulation of Xcc.
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, The Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering, and College of Life Science and Technology, Guangxi University, Nanning Guangxi, China.
authors.forename: Xiao-Lin
authors.initials: XL
authors.lastname: Chen
authors.forename: Dong-Jie
authors.initials: DJ
authors.lastname: Tang
authors.forename: Rui-Ping
authors.initials: RP
authors.lastname: Jiang
authors.forename: Yong-Qiang
authors.initials: YQ
authors.lastname: He
authors.forename: Bo-Le
authors.initials: BL
authors.lastname: Jiang
authors.forename: Guang-Tao
authors.initials: GT
authors.lastname: Lu
authors.forename: Ji-Liang
authors.initials: JL
authors.lastname: Tang
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D015152:Blotting, Northern; D004251:DNA Transposable Elements / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D032023:Integrons / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation; D009690:Nucleic Acid Conformation; D010802:Phylogeny; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D012329:RNA, Bacterial / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D058727:RNA, Small Untranslated / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D015534:Trans-Activators / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D014774:Virulence / Q000235:genetics; D016959:Xanthomonas campestris / Q000235:genetics* / Q000472:pathogenicity
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; C102404:HrpG protein, Xanthomonas campestris; C099784:HrpXv protein, Xanthomonas campestris; D012329:RNA, Bacterial; D058727:RNA, Small Untranslated; D015534:Trans-Activators; D014157:Transcription Factors