Project description:Here, we described a novel transcriptional regulator belonging to the MarR family that we named OsbR (oxidative stress response and biofilm formation regulator) in the opportunistic pathogen Chromobacterium violaceum. Transcriptome profiling by DNA microarray using strains with deletion or overexpression of osbR showed that OsbR exert a global regulatory role in C. violaceum, regulating genes involved in oxidative stress response, nitrate reduction, biofilm formation, and several metabolic pathways. EMSA assays showed that OsbR binds to the promoter regions of several OsbR-regulated genes and the in vitro DNA binding activity was inhibited by oxidants. We demonstrated that the overexpression of osbR caused activation of ohrA even in the presence of the repressor OhrR, which resulted in improved growth under organic hydroperoxide treatment. We showed that the proper regulation of the nar genes by OsbR ensures an optimal growth of C. violaceum under anaerobic conditions by tuning the reduction of nitrate to nitrite. Finally, the osbR overexpressing strain showed reduction in biofilm formation and this phenotype correlated with the OsbR-mediated repression of two gene clusters encoding putative adhesins.
Project description:We did bulk RNA sequencing in newborn cystic fibrosis (CF) and non-CF pig kidney. We compared kidney gene expression profiling between non-CF and CF pigs. RNA sequencing results showed that there is not significant difference between non-CF and CF in terms of gene expression, suggesting that CFTR knockout does not affect kidney development in newborn pigs.
