The AlgZR two-component system recalibrates the RsmAYZ posttranscriptional regulatory system to inhibit expression of the Pseudomonas aeruginosa type III secretion system.

ABSTRACT: Pseudomonas aeruginosa causes chronic airway infections in cystic fibrosis (CF) patients. A classic feature of CF airway isolates is the mucoid phenotype. Mucoidy arises through mutation of the mucA anti-sigma factor and subsequent activation of the AlgU regulon. Inactivation of mucA also results in reduced expression of the Vfr transcription factor. Vfr regulates several important virulence factors, including a type III secretion system (T3SS). In the present study, we report that ExsA expression, the master regulator of T3SS gene expression, is further reduced in mucA mutants through a Vfr-independent mechanism involving the RsmAYZ regulatory system. RsmA is an RNA binding protein required for T3SS gene expression. Genetic experiments suggest that the AlgZR two-component system, part of

SUBMITTER: Intile PJ 

PROVIDER: S-EPMC3911257 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature