EMSA revealed that MexZ binds to a 20bp palindromic sequence to the promoter region of the mexXY operon. EMSA and Western Blot showed higher levels of MexX and MexZ in the presence of tetracycline. Plasmid-borne MexZ repressed drug-induced MexX production confirming that MexZ acts as a repressor of the mexXY operon. EMSA and in vitro transcription assays revealed the interaction between PA5471 and MexZ reduces MexZ DNA-binding ablility, leading to mexXY transcription.
Regulated genes for each binding site are displayed below. Gene regulation diagrams show binding sites, positively-regulated genes, negatively-regulated genes, both positively and negatively regulated genes, genes with unspecified type of regulation. For each indvidual site, experimental techniques used to determine the site are also given.
|Site sequence||Regulated genes||Gene diagram||Experimental techniques||TF function||TF type|