J Mol Med (1995) 73:121-122 9Springer-Verlag 1995

G. Schultz 1994 for Medicine/

Prize in 1971. Two colleagues from the Cori laboratory, Edwin G. Krebs and Edmond H. Fischer, known as the "The Two Eds", investigated the muscle phosphorylase system and identified cyclic AMP-dependent protein ki- nase and established protein phosphorylation and de- phosphorylation as a general regulatory principle of pro- tein function. This work resulted in the 1992 Nobel Prize. By the end of the 1960s Earl W. Sutherland and his as- sociates G. Alan Robison and R. William Butcher had de- termined that receptors for the catecholamines, adrenaline and noradrenaline, and the regulated enzyme adenylyl cy- clase (at that time called adenyl-cyclase) represent do- mains or subunits of one protein. In 1971 Martin Rodbell and his associate Lutz Birnbaumer at the National Insti- Alfred G. Gilman Martin Rodbell tute of Health in Bethesda, , reported in a series of ground-breaking publications that the hormonal stimu- lation of adenylyl cyclase requires GTP and that GTP af- The 1994 Nobel Prize for physiology/medicine was fects the binding of hormonal agonists to their respective awarded to two American scientists, Alfred G. Gilman . Rodbell postulated that a GTP regulated "trans- and Martin Rodbell, for their work on G proteins. ducer" molecule might be involved between receptor and Numerous laboratories have studied the cellular com- adenylyl cyclase, at that time the only known effector munications that are necessary for coordinating cellular generating intracellular signal molecules. functions in the . Hormones, locally acting au- By the middle of the 1970s Thomas Pfeuffer, at the tacoids, neurotransmitters, and growth factors all act as laboratory of Ernst Helmreich in Wtirzburg, separated a extracellular signal molecules. Work on the cellular ef- GTP-binding protein from the other signal-transducing fects of these hormonal factors began during the 1940s components, i.e., adenylyl cyclase and receptors. At in the laboratory of the 1947 Nobel Prize winners, Carl about the same time Danny Cassel and Zvi Selinger and , at Washington University in St. Louis, working in Jerusalem showed that hormones stimulate Missouri. They were seeking to clarify the signal cas- GTP hydrolysis in membrane preparations. At this time cades from the receptors involved in regulation of cellu- Henry Bourne in San Francisco isolated some mutants of lar functions. While studying the regulation of gly- $49 lymphoma cells. One of them, called cyc-, became cogen phosphorylase, a former associate of the Coris, very important in research. Alfred G. Gilman Earl W. Sutherland, together with his associate Theo- began his career as a doctoral student of Ted Rall in the dore W. Rail, discovered cyclic AMP and established its Pharmacology Department chaired by Earl W. Suther- role as an intracellular signal molecule. Following this land at Case Western Reserve University in Cleveland, discovery, Earl W. Sutherland was awarded the Nobel Ohio. At the University of Virginia in Charlottesville, Virginia, Alfred Gilman was able to show that the $49 G. Schultz Institut fiir Pharmakologie, Universit~itsklinikumRudolf Virchow, cyc- mutant, in which there is no hormonal stimulation of Freie Universitat Berlin, Thielallee 67-73, adenylyl cyclase, actually does not have a defect in the D- 14195 Berlin, adenylyl cyclase but rather in the controlling G protein. 122 Using this tool, A1 Gilman with his associates John their capacity to switch on and off signal-transducing Northup and Paul Sternweis in 1980 accomplished the pathways such as regulation of cell proliferation and dif- first complete purification of a regulatory guanine nucle- ferentiation, ribosomal protein synthesis, intracellular otide-binding protein, i.e., of G s, the adenylyl cyclase- protein transport, secretion, cell motility, and other im- stimulating G protein. During the second half of the portant cellular functions. The G proteins, which have 1970s studies by Karl Heinrich Jakobs in Heidelberg and also long been called N proteins (for nucleotide-binding by Martin Rodbell revealed that many hormonal factors proteins), represent only one subfamily of the GTP-bind- inhibit adenylyl cyclase in a GTP-dependent manner, and ing proteins. Because G proteins are composed of three soon thereafter A1 Gilman's laboratory purified the G subunits (c~, [3, 7), they are also designated as heterotri- protein involved, G i. They also isolated G O(for "other" G meric G proteins to distinguish them clearly from low protein) which is now known to be involved in receptor- molecular weight or monomeric GTP-binding proteins, mediated inhibition of voltage-dependent calcium chan- for example, ras and related proteins. nels. Martin Rodbell (age 68), who made early conception- Alfred G. Gilman and his group have provided nu- al contributions to G-protein-mediated signal transduc- merous important contributions elucidating the structure tion when he worked at the National Institute of Health and functions of these and other G proteins involved in in Bethesda, Maryland, has recently retired from the Na- from receptors to effectors such as tional Institute of Environmental Health in Research Tri- adenylyl cyclases and other enzymes as well as ion chan- angle Park, North Carolina. Alfred Goodman Gilman nels. This three-component signal transduction principle (age 53) has been Professor and Chairman for many is involved not only in signal transduction processes in- years at the Department of Pharmacology, Southwestern duced by chemically defined intercellular signals but Medical Center, University of Texas in Dallas, Texas. We also in sensory signal transductions induced by light or can assume that he and his group will provide many olfactants. The receptors interacting with G proteins to more outstanding contributions on the structure and induce cellular reactions is presently thought to number function of G proteins. In addition to his scientific work, about one thousand. AI Gilman is known as the editor of the concise textbook A superfamily of GTP-binding proteins are now of pharmacology, Goodman and Gilman's The Pharma- known which catalyze GTP hydrolysis and are therefore cological Basis of Therapeutics, founded by his father, also called . These proteins are characterized by Alfred Gilman, and Louis S. Goodman.