title: Identification and characterization of a cis antisense RNA of the parC gene encoding DNA topoisomerase IV of Salmonella enterica serovar Typhi.
abstract: Bacterial cis-encoded antisense RNAs are transcribed from the opposite strand of protein coding genes, and their regulatory roles adapt cells to changing environmental conditions. By deep sequencing of the transcriptome of Salmonella enterica serovar Typhi, an antisense RNA that is encoded in cis to the parC gene was found. parC encodes the subunit A component of topoisomerase IV, a class of enzymes that relax both positively and negatively supercoiled DNA and are also required for segregation of daughter chromosomes in bacteria. Transcription of the 871 nucleotide antisense RNA was confirmed by northern blot and RACE analysis to be expressed mostly in the stationary phase of bacterial growth and also upregulated in iron limitation and osmotic stress conditions. Overexpression of the antisense RNA resulted in a significant increase in parC mRNA levels. Further analysis revealed that expression of the antisense RNA stabilizes the target mRNA, probably by protecting it from endoribonucleases. Our findings confirm and add to the ever increasing knowledge of the important role that regulatory antisense RNAs play in bacteria.
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China; Department of Laboratory Technology, University of Cape Coast, Cape Coast, Ghana. Electronic address: iedadzie@yahoo.co.uk.
authors.forename: Isaac
authors.initials: I
authors.lastname: Dadzie
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China. Electronic address: nibinbb@yahoo.com.cn.
authors.forename: Bin
authors.initials: B
authors.lastname: Ni
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China. Electronic address: 754212224@qq.com.
authors.forename: Mingyu
authors.initials: M
authors.lastname: Gong
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China. Electronic address: 105850077@qq.com.
authors.forename: Zhang
authors.initials: Z
authors.lastname: Ying
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China. Electronic address: zhanghf@ujs.edu.cn.
authors.forename: Haifang
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China. Electronic address: shengxiumei@hotmail.com.
authors.forename: Xiumei
authors.initials: X
authors.lastname: Sheng
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China. Electronic address: xusg@ujs.edu.cn.
authors.forename: Shungao
authors.initials: S
authors.lastname: Xu
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Medical Science and Laboratory Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China. Electronic address: huxinx@ujs.edu.cn.
authors.forename: Xinxiang
authors.initials: X
authors.lastname: Huang
mesh_terms: D015152:Blotting, Northern; D027101:DNA Topoisomerase IV / Q000096:biosynthesis* / Q000235:genetics*; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D059014:High-Throughput Nucleotide Sequencing; D020871:RNA Stability; D016372:RNA, Antisense / Q000235:genetics*; D012485:Salmonella typhi / Q000201:enzymology* / Q000235:genetics*
chemical_list: D016372:RNA, Antisense; D027101:DNA Topoisomerase IV
keywords: Antisense RNA; DNA replication; Gene expression/regulation; Salmonella enterica serovar Typhi