|REDFERN, CRYSTAL - Wake Forest School Of Medicine|
|GANGULY, TRIDIB - Wake Forest School Of Medicine|
|CONOVER, MATT - Wake Forest School Of Medicine|
|DEORA, RAJENDAR - Wake Forest School Of Medicine|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/15/2013
Publication Date: 9/8/2013
Citation: Redfern, C., Ganguly, T., Conover, M.S., Nicholson, T.L., Deora, R. 2013. BpsR functions as a dual activator and repressor of Bordetella gene expression. 10th International Symposium on Bordetella. p. 46.
Technical Abstract: Bordetella bacteria are Gram-negative respiratory pathogens of animals, birds, and humans. A hallmark feature of some Bordetella species is their ability to efficiently survive in the respiratory tract even after vaccination. Our overall hypothesis is that establishment of colonization and persistence is enhanced by formation of biofilms in the respiratory tract. Bordetella bronchiseptica and Bordetella pertussis form biofilms on abiotic surfaces and in the mouse respiratory tract. The Bps exopolysaccharide is one of the critical determinants for biofilm formation and the survival of Bordetella in the murine respiratory tract. Regulatory pathways controlling biofilm development and polysaccharide gene expression are poorly understood in Bordetella. We previously identified, BpsR as a regulator of biofilm formation. By repressing the expression of Bps, BpsR inhibits biofilm development. By carrying out DNAse I footprinting assays, we have identified regions protected by BpsR on bpsA-D. The protected region harbors a highly unusual complex array of symmetry elements in the form of inverted, complementary inverted, mirror-like direct repeats and nine repeats of a loosely conserved hexameric sequence with a consensus G/C(A/T)4G/C. Single round in vitro transcription assays showed that BpsR is sufficient to repress transcription from the bpsA-D promoter. Transcriptome profiling revealed that BpsR functions as global regulator and can both activate and repress gene expression. The results from this study provide insight into regulation of large gene networks in which transcription factors must play both positive and negative roles.