Dual function of PilS during transcriptional activation of the Pseudomonas aeruginosa pilin subunit gene.

摘要: The polar pili of Pseudomonas aeruginosa are composed subunits encoded by the pilA gene. Expression requires alternative sigma factor RpoN and a pair regulatory elements, PilS PilR. These two proteins members two-component family, in which is sensory component PilR response regulator. By using expression localization analyses, this work we show that synthesized as 59-kDa polypeptide located P. cytoplasmic membrane. When pilS gene expressed Escherichia coli, aberrant translational initiation results smaller, 40-kDa polypeptide. Unexpectedly, overexpression decreased transcription Moreover, fully functional was not required for inhibitory effect. A mutation histidine residue essential kinase activity resulted protein unable to activate transcription, yet when overexpressed presence wild-type protein, still repressed pilin synthesis. shorter form PilS, lacking its transmembrane segments, active capable stimulating but did effect on seen with full-length PilS. We also pilR can even absence On basis our studies, propose complex mechanism regulation function, involving other cellular factors control activities during phosphorelay signal transduction.