Structure and Function of Membrane Proteins

The University Of Texas Health Science Center At Houston, Houston TX

Investigators

Abstract

Lay Summary 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. An important member of this family is the glutamate receptor, which is the focus of this study. These receptors bind to the chemical signaling molecule glutamate (ligand) and generate an electrical signal through the formation of transmembrane ion channels. Dr. Jayaraman's laboratory has used vibrational spectroscopy to identify specific interactions between the glutamate receptor protein and ligands such as glutamate. Since, the vibrations of these chemical moieties are controlled by their atomic-level environment, probing these by infrared light has provided insight into the interaction between the protein and the ligand. Dr. Jayaraman will investigate the identified ligand:protein interactions in a time-resolved manner. For these investigations glutamate will be photolytically released in the microsecond timescale using caged glutamate and the kinetic evolution of the vibrational spectral signatures of the ligand and protein will be investigated as the protein evolves from the unligated to the ligated states. These high-resolution structural and kinetic 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.