Selective inhibition of type III secretion activated signaling by the Salmonella effector AvrA.

ABSTRACT: Salmonella enterica utilizes a type III secretion system (TTSS) encoded in its pathogenicity island 1 to mediate its initial interactions with intestinal epithelial cells, which are characterized by the stimulation of actin cytoskeleton reorganization and a profound reprogramming of gene expression. These responses result from the stimulation of Rho-family GTPases and downstream signaling pathways by specific effector proteins delivered by this TTSS. We show here that AvrA, an effector protein of this TTSS, specifically inhibits the Salmonella-induced activation of the JNK pathway through its interaction with MKK7, although it does not interfere with the bacterial infection-induced NF-kappaB activation. We also show that AvrA is phosphorylated at evolutionary conserved residues by a TTSS-e

SUBMITTER: Du F 

PROVIDER: S-EPMC2742890 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature