Alfred G. Gilman
The University of Texas Southwestern Medical Center at Dallas
Election Year: 1985
Primary Section: 23, Physiology and Pharmacology
Membership Type: Member
The most common mechanism for transmission of information into cells from hormones, neurotransmitters, and other regulators that reach the cell surface involves the concerted action of three types of plasma membrane-associated proteins: hormone receptors, heterotrimeric guanine nucleotide-binding regulatory proteins (G proteins), and signal generators or effectors. One such effector, the enzyme adenylyl cyclase, is responsible for synthesis of the intracellular second messenger cyclic AMP (from ATP). G proteins serve as essential coupling factors between a large number of receptors and adenylyl cyclase. One, Gs, stimulates cyclic AMP synthesis, while the other, Gi, is inhibitory. We are engaged in biochemical, molecular biological, and structural studies of both G proteins and adenylyl cyclases. The structures of several of these molecules have been determined recently by X-ray crystallography, and the ligand-protein and protein-protein interactions that are responsible for integration, transduction, and amplification of cellular regulatory signals as they traverse the plasma membrane are understood in increasingly fine detail.