Oxygen-dependent regulation of SPI1 type three secretion system by small RNAs in Salmonella enterica serovar Typhimurium.

ABSTRACT: Salmonella Typhimurium induces inflammatory diarrhea and uptake into intestinal epithelial cells using the Salmonella pathogenicity island 1 (SPI1) type III secretion system (T3SS). Three AraC-like regulators, HilD, HilC and RtsA, form a feed-forward regulatory loop that activates transcription of hilA, encoding the activator of the T3SS structural genes. Many environmental signals and regulatory systems are integrated into this circuit to precisely regulate SPI1 expression. A subset of these regulatory factors affects translation of hilD, but the mechanisms are poorly understood. Here, we identified two sRNAs, FnrS and ArcZ, which repress hilD translation, leading to decreased production of HilA. FnrS and ArcZ are oppositely regulated in response to oxygen, one of the key environmental si

SUBMITTER: Kim K 

PROVIDER: S-EPMC6417950 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature