Determinants of specificity in two-component signal transduction.
Maintaining the faithful flow of information through signal transduction pathways is critical to the survival and proliferation of organisms. This problem is particularly challenging as many signaling proteins are part of large, paralogous families that are highly similar at the sequence and structural levels, increasing the risk of unwanted cross-talk. To detect environmental signals and process information, bacteria rely heavily on two-component signaling systems comprised of sensor histidine kinases and their cognate response regulators. Although most species encode dozens of these signaling pathways, there is relatively little cross-talk, indicating that individual pathways are well insulated and highly specific. Here, we review the molecular mechanisms that enforce this specificity. Further, we highlight recent studies that have revealed how these mechanisms evolve to accommodate the introduction of new pathways by gene duplication.
Computational & Systems Biology Initiative, Massachusetts Institute of Technology, Cambridge, MA 02139, United States.
Anna I
AI
Podgornaia
Michael T
MT
Laub
D001419:Bacteria / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D018407:Bacterial Physiological Phenomena; D001426:Bacterial Proteins / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D000071677:Histidine Kinase; D011494:Protein Kinases / Q000378:metabolism; D012808:Sigma Factor / Q000378:metabolism; D015398:Signal Transduction; D013312:Stress, Physiological
D001426:Bacterial Proteins; D012808:Sigma Factor; D011494:Protein Kinases; D000071677:Histidine Kinase