A Non-coding Small RNA MicC Regulates Virulence and Outer Membrane Proteins Expression in Salmonella enteritidis
Non-coding small RNA (sRNA)is a new factor to regulate gene expression at post-transcriptional level.MicC is a sRNA existed in Escherichia coli and Salmonella typhimurium which can repress the expression of outer membrane proteins OmpC and OmpD respectively.In recent years,Salmonella enteritidis has become the most prevalent non-typhoidal serovar m many countries.To investigate the regulation function of micC in other target genes and virulence for animals,we cloned the micC gene in the strain S.enteritidis 50336,and then constructed the mutant 50336ΔmicC by the λ Red-based recombination system and the complemented mutant c50336ΔmicC carrying recombinant plasmid pBR322 expressing micC.Novel target genes were screened by qRT-PCR.The results demonstrated that transcription of ompD in 50336ΔmicC was increased slightly (1.3-fold)than that in wild type strain,while the protein expression of OmpD was increased evidently in 50336ΔmicC.In addition,the transcription of ompA and ompC in 50336ΔmicC increased about 2.2-fold and 3-fold than those in wild type strain.It indicated that micC could repress the expression of ompA and ompC.OmpA was probably a novel target genes regulated by micC directly.Because OmpA and OmpD were related to adhesion to host cells and mediated virulence finally,the pathogenicity of 50336ΔmicC was detected by both infecting 6-week-old Balb/c mice by intraperitoneal injection and 1-day-old chickens by hypodermic injection.The result showed that the LDso of the wild type strain 50336,the mutants 50336ΔmicC and c50336ΔmicC for 6-week-old Balb/c mice were 12.59 cfu,5.01 cfu,19.95 cfu respectively.The LD50 for 1-day-old chickens were 1.13×109 cfu,1.55 x lO8 cfu,2.54 x lO8 cfu respectively.It indicated that deletion of micC enhanced virulence of S.enteritidis in mice and chickens by regulating expression of outer membrane proteins,especially OmpA and OmpD.
Meng Xia Cui Weiwei Meng Xianchen Wang Heng Zhu Chunhong Nie Jiajia Zhu Guoqiang
Ministry of Education Key Lab for Avian Preventive Medicine,College of Veterinary Medicine,Yangzhou Jiangsu provincial key lab for genetics and breeding of poultry,Jiangsu Institute of Poultry Science
国际会议
XVIth International Congress on Animal Hygiene(第十六届动物卫生国际会议(ISAH 2013))
南京
英文
483-485
2013-05-05（万方平台首次上网日期，不代表论文的发表时间）