23 May 2008
Uri Alon
Weizmann Institute
Part I: science is ideologically associated with objectivity and rationality. Thus, subjective and emotional aspects, so important for our well-being and performance as researchers, are usually not considered Science. They are rarely discussed in professional settings, leaving scientists to discover for themselves how to survive graduate school and postdocs, how to mentor, how to face the existential challenges of a person trying to learn something new about nature. Ill discuss the impact that the neglect of subjective/emotional has on science and scientists.
Part II: we will look at a gene circuit, with several well-characterized but puzzling biochemical details, that are found in a class of bacterial two component signaling systems (such as OmpR-EnvZ of E. coli). While each such detail has little meaning by itself, when considered together they can be seen to perform a systems level function: they make the input-output relation perfectly insensitive (perfectly robust) to all variations in the concentrations of the proteins that make up the system. The fundamental mechanism for perfect robustness, involving bifunctional enzymes and auto-phosphorylation, can be in principle generalized to other signaling systems.