The molecular switch and monod’s second secret of life

Submitted by iherna13 on July 5, 2017 - 1:43pm

Abstract: Only ten years after the discovery of the iconic structure of DNA, new questions were on biologist’s minds, namely, how are the macromolecules of the cell regulated so that they do what they are supposed to when and where they are needed. The initial resolution of the challenging question of biological regulation came in the form of the notion of “allostery”, an idea that its discoverer Jacques Monod himself referred to as "the second secret of life". We recently celebrated the 50th anniversary of the classic paper of Monod, Changeux and Jacob that introduced this far reaching idea. That important paper was followed shortly thereafter by a second one that revealed their musings on how simple statistical mechanical models can be used to capture how such allosteric transitions work mechanistically. In this talk, I will review the key features of the famed Monod-Wyman-Changeux (MWC) model and then describe its broad reach across many different domains of biology with special reference to the physics underlying how genes are turned on and off. One of the intriguing outcomes of this class of models is a beautiful and predictive scheme for collapsing data from entire libraries of mutants. Once we have considered some of the traditional uses of the MWC model, I will turn to more speculative recent ideas which use the MWC approach to consider the nature of kinetic proofreading.

Biography: Rob Phillips grew up in San Diego, California in a home filled with books, leading to a love affair with books and reading that has continued to this day. He is the Fred and Nancy Morris Professor of Biophysics and Biology at the California Institute of Technology in Pasadena, California. Phillips received his PhD in condensed matter physics at Washington University in 1989 studying with Anders Carlsson from whom he learned an enormous amount about the conduct of science and about science itself. Prior to the great fun of a life in science, he spent seven years of travel, self-study and work as an electrician. Though teaching is often viewed within research universities as a chore, Phillips finds teaching to be a central part of his attempt to learn more about how the world works. Stated simply, writing books is an intense and personal experience that Rob links to his teaching and is the primary way he is able to really learn a subject. He is currently engaged in several book projects, one of which focuses on the statistical mechanics of cell signaling and the other of which with Hernan Garcia provides a quantitative view of gene expression.

Thursday, November 9, 2017
Robert Phillips
California Institute of Technology
Banu Ozkan