GSE122253
Comparative RNA-seq analysis of the transcriptome of the Pseudomonas aeruginosa PAO1 wild-type strain with that of the ?vreR mutant
Bacterial gene expression is controlled by modifying the promoter affinity of the RNA polymerase (RNAP). This control occurs through the substitution of the RNAP s subunit and by the interaction with transcription factors. The pathogen Pseudomonas aeruginosa contains several s factors, including sVreI. This protein belongs to the extracytoplasmic function group of the s70 family. Expression and activity of sECFs are tightly regulated and only occur in response to specific signals. sVreI is encoded within the vreAIR gene cluster. The expression of this cluster occurs in response to inorganic phosphate (Pi) limitation. sVreI activity is modulated by VreR anti-sigma factor, which keeps sVreI inactive. In response to a still unidentified host signal, VreR is proteolytically degraded and sVreI released and activated. sVreI interacts then with the RNAP and targets expression of the sVreI regulon, which includes virulence genes that increase P. aeruginosa pathogenicity. In this work, we compared the transcriptome of the P. aeruginosa PAO1 wild-type strain with that of the ?vreR mutant upon bacterial growth in Pi starvation. Forty-six transcripts were more abundant in the ?vreR mutant than in the PAO1 wild-type strain, and nine were less abundant, including the vreR transcript. Overall design: P. aeruginosa PAO1 and ?vreR mutant were grown until late exponential phase in low Pi medium and total RNA was isolated. A mixture of the three isolations was used for RNA-seq analyses.