UNDERSTANDING THE MOLECULAR BASIS OF PROTEIN ALLOSTERY BY DEEP MUTATIONAL SCANNING
Allostery has a central place in biology due to the myriad roles of allosteric proteins in cellular function, including signal transduction, catalysis, metabolism, gene regulation and transport. Allostery is regulation from a distance – perturbation at one site of a protein causes an effect at a distant site. Once a gene is transcribed and translated, allostery is the primary mode of regulation of a protein function inside the cell. Allostery can be understood in simple terms as follows: when a protein is perturbed by binding to an effector (Eg.: small molecule, nucleic acid or another protein) at a site called the allosteric site, it triggers a change in conformation from inactive to active state that then regulates a distally located active site. This property is remarkable because enables two sites within a protein to communicate with each other despite being separated by a large distance. Since the discovery of allostery several decades back, the question that remains unanswered is what is the molecular mechanism by which distal sites communicate with each other? The goal of our research is to develop a data-driven framework, to understand, quantify, and predict molecular drivers of protein allostery by deep mutational scanning. We integrate large scale mutational screens with targeted NMR relaxation experiments to ‘observe’ residues undergoing motion in the micro-to-millisecond timescales to map the allosteric pathway and investigate the existence of multiple allosteric pathways in a protein.