Project description:To understand differences of gene expression profiles between Francisella strains RNA profiles of Francisella strains were generated by deep sequencing, in triplicate, using NovaSeq6000. qRT–PCR validation was performed using SYBR Green assays. Our study represents the first detailed differential transcriptomic analysis of Francisella strains , with biologic replicates, generated by RNA-seq technology.
Project description:The genus Francisella includes several species that cause zoonotic diseases and that have evolved to develop different strategies for survival within the host cells. Despite the critical importance of the diseases caused by members of the genus Francisella, the DNA repair mechanisms of this pathogen remain understudied. In this work, the transcriptional response of Francisella hispaniensis to the DNA-damaging agent ciprofloxacin was studied using RNA sequencing. Among the differentially expressed genes, we identified a S24 family peptidase-encoding gene. Electrophoretic mobility shift assays demonstrated that the product of this gene specifically binds to the palindromic sequence GTG-N11-CAC present in its promoter region, resulting in autoregulation. In silico analyses revealed that this S24 peptidase, here termed FddR, is most likely a co-opted phage repressor that implements a DNA-damage response across the Francisella genus. Our results provide insights into the SOS repair system of Francisella spp. and suggest that the identified S24 family peptidase is a direct regulator of the DNA damage response in F. hispaniensis.