GILMAN, ALFRED G.

born July 1, 1941, New Haven, Conn., U.S. in full Alfred Goodman Gilman American pharmacologist who shared the 1994 Nobel Prize for Physiology or Medicine with American biochemist Martin Rodbell for their separate research in discovering molecules called G proteins, which are intermediaries in the multistep pathway cells use to react to an incoming signal, such as a hormone or neurotransmitter. Gilman attended Yale University (B.S., 1962) and Case Western Reserve University (M.D. and Ph.D., 1969), where he studied under Nobel Prize recipient Earl W. Sutherland, Jr. Gilman worked at the National Institutes of Health (196971) and taught at the University of Virginia (197181) before becoming the director of the pharmacology department at the University of Texas Southwestern Medical Center in Dallas in 1981. In the 1960s Rodbell demonstrated that a cell's response to a chemical signal involves not only a receptor for the signal at the cell's surface and an amplifier that functions within the cell, as was already known, but also an intermediary molecule that transduces, or relays, the message from receptor to amplifier. Gilman, working in the 1970s with mutant cells that were unable to send signals properly, identified the intermediary signaling molecule as a G protein, so named because it becomes activated when bound to a molecule called guanosine triphosphate (GTP). Abnormally functioning G proteins can disrupt the normal signal transduction process and play a role in diseases such as cholera, cancer, and diabetes.