mutation regulated avian pathogenicpathogenicity though stress-resistance pathway.

Abstract

gene mutation decreased the pathogenicity of the avian pathogenicstrain, AE17. However, the associated regulatory mechanism ofremains unknown. In this study, we examined the bactericidal activity of chicken serum and blood, as well as bacterial survival in HD11 macrophages. We compared the transcriptome ofmutations with those of the wild strain and studied the effects ofon miRNA expression in the spleen. Our findings revealed that the mutant strain, Δ, had a lower resistance to chicken serum and blood, as well as lower bacterial survival in HD11 macrophages than AE17. RNA sequencing analyses showed that themutation reduced stress resistance by down-regulating mRNAs in metabolic pathways. Infection with themutant strain caused changes in the splenic miRNA profile. We verified Kelch repeat and BTB domain-containing protein 11 to be the target of miR-133b. Together, these findings suggest that themutation reduces serum, blood, and environmental stress resistance by down-regulating the mRNA in metabolic pathways.