Structure and Function of Membrane Proteins

Marquette University, Milwaukee WI

Investigators

Abstract

9982759 Jayaraman Communication between nerve cells serves as the basis of all brain activity. One of the fundamental steps involved in signal transmission between the nerve cells, is the conversion of a chemical signal liberated at the end of one nerve cell, into an electrical signal at the second nerve cell. This step is mediated by a class of membrane bound proteins known as neurotransmitter receptors. One member of this family is the glutamate receptor. These receptors bind to the chemical signaling molecule glutamate (ligand) and generate an electrical signal through the formation of transmembrane ion channels. In the proposed studies, Dr. Jayaraman will attempt to understand the interactions whereby the glutamate receptor protein specifically recognizes ligands such as glutamate. The ligand-protein interactions will be investigated by probing the vibrations of the ligand and the ligand-binding segment of the glutamate receptor using spectroscopic tools. Since, the vibrations of these chemical moieties are controlled by their atomic-level environment, probing the vibrations with infrared light will provide insight into the interaction between the protein and the ligand. Furthermore, extending these studies to study the changes in the protein structure upon ligand binding in a time-resolved manner, will suggest the pathway by which the protein form the ion channels upon binding the ligand. These high-resolution structural studies are required for a basic understanding of interactions that control protein-ligand recognition and will eventually allow the design of drugs that can alter the behavior of glutamate receptors. Such drugs may be useful in the treatment of traumatic head injury, and memory problems.