Susan G. Amara

Biosketch

Michael S. Brown received an M.D. degree in 1966 from the University of Pennsylvania. He was an intern and resident at the Massachusetts General Hospital, and a post doctoral fellow with Earl Stadtman at the National Institutes of Health. He is currently Paul J. Thomas Professor of Molecular Genetics and Director of the Jonsson Center for Molecular Genetics at the University of Texas Southwestern Medical School in Dallas. Dr. Brown and his colleague, Dr. Joseph L. Goldstein, discovered the low density lipoprotein (LDL) receptor, which controls cholesterol in blood and in cells. They showed that mutations in this receptor cause Familial Hypercholesterolemia, a disorder that leads to premature heart attacks. Their work laid the groundwork for drugs called statins that block cholesterol synthesis, increase LDL receptors, lower blood cholesterol and prevent heart attacks. Statins are taken daily by more than 20 million people worldwide. Brown and Goldstein shared many awards for this work, including the U.S. National Medal of Science and the Nobel Prize for Medicine or Physiology. Dr. Brown served for 16 years on the Board of Directors of Pfizer, and he is currently a Director of Regeneron Pharmaceuticals.

Research Interests

Research in our laboratory focuses on neurotransmitter transporters, the plasma membrane proteins that limit the actions of neurotransmitters following their release from neurons. These carrier proteins catalyze the inward movement of neurotransmitter molecules and have a profound impact on the extent of receptor activation that occurs during neuronal signaling. We have also shown that these transporters can possess a substrate-dependent ion channel-like activity, a property that allows them to regulate neuronal excitability and serve as sensors of extracellular neurotransmitter concentrations. Neurotransmitter transporters are also well-established targets for addictive drugs, including cocaine and amphetamines, for the class of therapeutic antidepressants known as reuptake inhibitors, and for methylphenidate, which is used to treat attention deficit hyperactivity disorders. Our major efforts use molecular genetic, electrophysiological and cell biological approaches to explore the relationships between neurotransmitter transporter structure, substrate transport, drug action and ion permeation.