|Faculty lecture today focuses on dopamine transporters|
Roxanne Vaughan will unravel the secrets of the dopamine transporter and its effect on the human brain and stimulants like cocaine when she delivers the next installment of the University Faculty Lecture Series. “Dopamine Transporters: What’s Regulating the Regulator?” is scheduled for Tuesday, Nov. 7, at 4:30 p.m. in the North Dakota Museum of Art. A 4 p.m. reception will precede the lecture, which is free and open to the public.
“The dopamine transporter (DAT) is a protein known as the ‘regulator’ because it controls the availability of dopamine in the brain for neurotransmission, which in turn affects many processes including motor activity, emotion, and reward,” said Vaughan, an associate professor in the UND Department of Biochemistry and Molecular Biology. “DAT is subject to multiple types of complex regulatory events and dysfunctions in these processes may lead to psychiatric or mood disorders.”
A common example of dysfunctions in DAT processes occurs when individuals consume psychostimulants such as cocaine and amphetamine. “These drugs block dopamine reuptake, producing elevated dopamine levels believed to underlie drug reinforcement,” Vaughan said. “Cocaine binds to DAT and inhibits its activity, which means that dopamine clearance is blocked and the dopamine builds up in the synaptic space between nerve cells. This buildup of dopamine overstimulates the downstream neurons which is what causes the hyperactivity and euphoria associated with drug use.”
“DAT is also associated with several diseases related to dopamine, including Parkinson’s disease, depression, and schizophrenia,” said Vaughan. “These disorders are characterized by abnormal dopamine levels, which could be caused by DAT working either too rapidly (producing low dopamine levels) or too slowly (leading to high dopamine levels). Identifying the processes that control DAT functions could lead to a better understanding of how these processes may be improperly regulated in disease.”
Roxanne Vaughan is an associate professor in the Department of Biochemistry and Molecular Biology. She was born in North Dakota and was raised in Colorado. She received the bachelor's degree in biology from Colorado State University, a master's degree in zoology from the University of California at Davis, and her doctorate in zoology from Virginia Polytechnic Institute and State University. She was a postdoctoral fellow in the laboratory of Peter Devreotes in the Department of Biological Chemistry at the Johns Hopkins University School of Medicine, followed by appointment as a Senior Staff Fellow at the National Institute on Drug Abuse in the laboratory of Michael J. Kuhar.
Vaughan’s research interests include protein structure-function relationships and regulation of proteins by phosphorylation. Her early work involved studies of protein kinase A mechanisms and G protein coupled receptors in Dictyostelium discoideum, and her more recent work has focused on structure, regulation, and post-translational modifications of dopamine transporters. She has promoted the development and use of structurally diverse photoaffinity labels to identify transporter drug binding sites and characterize binding domain structure, and has analyzed dopamine transporter phosphorylation and regulation properties in both model and native systems under a variety of conditions related to endogenous control and drug-induced adaptations.
Vaughan is married to Jefferson A. Vaughan, associate professor of biology at UND. They have two teenaged daughters.
The Faculty Lecture Series is planned by Chester Fritz Distinguished Professors, who hold UND’s highest faculty honor, and is funded by the UND Office of the President.