BioProject

APEC cause avian colibacillosis in poultry, characterized by the systematic infection, such as septicemia, airsacculitis, and pericarditis. APEC mainly use two-component regulatory systems (TCSs) to deal with the stressing environments in host during their infection. Whereas most TCSs in E.coli are well characterized, the characterization of RstA/RstB in APEC has not been thoroughly investigated. To understand the whole picture of RstA/RstB regulation, especially its role in virulence regulation, transcriptional analysis of the effect of rstAB deletion was performed in vivo. We compared the transcriptome of rstAB mutant and its wild-type strain during their growth in bloodstream of challenged chickens. In total, the transcripts of 85 genes were down-regulated by rstAB deletion while 113 were up-regulated at least twofold (cutoff limitation for fold change >2 or <0.5 and Cuffdiff P-value <0.05 was used to select differential expression genes). Our data showed that the RstA/RstB was a by-function regulator system, acting as both an activator and a repressor. The RstAB mainly regulated systems involved in nitrogen metabolism, bacterial virulence, iron acquisition and acid resistance. Overall design: We contructed the rstAB mutant and compared the transcriptome of rstAB mutant and its wild-type strain during their growth in bloodstream of challenged chickens