24 October 2008
Mark Goulian
Department of Biology
University of Pennslyvania
Two-component systems are one of the major modes of signal transduction in bacteria. These circuits, which play a central role in regulating adaptive responses to diverse environmental signals, have been uncovered in remarkable numbers within individual organisms and across different bacterial species. The "two components" refer to two regulatory proteins – an upstream sensor kinase and downstream response regulator. The flow of information is through phospho-transfer. Although these systems show considerable variability in their degree of complexity, even the simplest examples have numerous subtle and interesting design features. After a brief introduction, I will discuss some of our recent work on several well-studied systems in which we have explored the effects of positive autoregulation and mechanisms of cross-talk suppression.