FIG 7.
Hfq and sRNA 179 inhibit the cAMP-Vfr signaling system. (A) WT PA103 or an hfq mutant transformed with the indicated expression vectors were assayed for Vfr-dependent PexsA-lacZ transcriptional reporter activity. WT PA103 carrying a promoterless lacZ transcriptional reporter was included as a control for background activity. *, P < 0.05. (B) The indicated strains were transformed with a vector control or an Hfq expression vector and assayed for vfr’-’lacZ translational reporter activity and Vfr protein levels by immunoblot. *, P < 0.001. (C) Twitching motility zones for P. aeruginosa strains PA103, PAK, and PA14 carrying a vector control (pJN105) or an Hfq expression vector. *, P < 0.05.