Bistability in the Bacillus subtilis K-state (competence) system requires a positive feedback loop

@article{citeulike:154056, abstract = {High expression of the transcriptional activator ComK occurs in 10–20\% of the cells in stationary phase cultures of Bacillus subtilis strain 168. ComK drives the expression of more than 100 genes constituting the semidormant K-state, distinct from sporulation and vegetative growth. Among the genes so activated are those that permit competence for genetic transformation. We have addressed the origin of bistability in expression of ComK. We show that bistability requires positive autoregulation at the promoter of comK, but not a potential toggle switch, in which ComK represses the promoter of rok and Rok represses the promoter of comK. We further address the source of the noise that results in the stochastic selection of cells that will express comK. A revised model for the regulation of comK expression is proposed that partially explains bistability.}, author = {Maamar, Hedia and Dubnau, David }, citeulike-article-id = {154056}, doi = {http://dx.doi.org/10.1111/j.1365-2958.2005.04592.x}, issn = {0950-382X}, journal = {Molecular Microbiology}, keywords = {bistability, bsubtilis, competence}, month = {May}, number = {3}, pages = {615--624}, posted-at = {2008-03-25 17:17:39}, priority = {2}, publisher = {Blackwell Publishing}, title = {Bistability in the Bacillus subtilis K-state (competence) system requires a positive feedback loop}, url = {http://dx.doi.org/10.1111/j.1365-2958.2005.04592.x}, volume = {56}, year = {2005} }

TY - JOUR ID - citeulike:154056 L3 - citeulike-article-id:154056 N2 - High expression of the transcriptional activator ComK occurs in 10–20% of the cells in stationary phase cultures of Bacillus subtilis strain 168. ComK drives the expression of more than 100 genes constituting the semidormant K-state, distinct from sporulation and vegetative growth. Among the genes so activated are those that permit competence for genetic transformation. We have addressed the origin of bistability in expression of ComK. We show that bistability requires positive autoregulation at the promoter of comK, but not a potential toggle switch, in which ComK represses the promoter of rok and Rok represses the promoter of comK. We further address the source of the noise that results in the stochastic selection of cells that will express comK. A revised model for the regulation of comK expression is proposed that partially explains bistability. IS - 3 JF - Molecular Microbiology SN - 0950-382X EP - 624 TI - Bistability in the Bacillus subtilis K-state (competence) system requires a positive feedback loop PB - Blackwell Publishing VL - 56 SP - 615 KW - bistability KW - bsubtilis KW - competence AU - Maamar, Hedia AU - Dubnau, David PY - 2005/05// UR - http://dx.doi.org/10.1111/j.1365-2958.2005.04592.x ER -