somA require the response regulator PhoP for expression To determine whether the expression of somA is regulated by transcription factors , the GFP report-ers were transduced into Salmonella strains with mutations in one of the following genes : rpoS .
VirK require the response regulator PhoP for expression To determine whether the expression of somA is regulated by transcription factors , the GFP report-ers were transduced into Salmonella strains with mutations in one of the following genes : rpoS .
These results indicate that phoP may control the expression of the rpoS gene , as substantiated by previous reports that PhoP controls the expression of rpoS gene .