NASHVILLE, Tenn. ñ Call it the illuminated brain cell: Imagine a neuron decked out with thousands of tiny red, yellow, green and blue lights. As the neuron fires and recovers, visualize these lights as blinking on and off, moving this way and that, revealing the location and movement of the nerve’s molecular machinery in action.
Sandy Rosenthal and the interdisciplinary science team that she heads are working to make this vision into a reality, and they have received $1.4 million in funding from the National Institutes of Health to pursue this goal. This is Vanderbilt’s first NIH award under the new Nanoscale Science and Nanotechnology in Biology and Medicine program.
The project is at the intersection of two of today’s hottest scientific fields: nanotechnology and neuroscience. The tiny lights are nanocrystals, which are about one- thousandth the size of a human cell and fluoresce in a variety of colors. Using them as biological probes, scientists can see the locations and track the movements of different pieces of the cell’s invisible molecular machinery by tagging them with the tiny colored lights.
The new project has two basic goals: improving the efficiency of nanocrystals ñ also called quantum dots ñ and developing a reliable method to attach them to the various structures that stud the outer membrane of nerve cells. The technology the project develops should not only provide new insights into the molecular nature of neural processes, including depression, addiction and learning, but also may serve as a powerful new tool for the drug discovery process.
"We have a saying around here: ‘We don’t make quantum dots, but we help make them better,’" says Rosenthal, who is an associate professor of chemistry and physics at Vanderbilt. Her team members include Assistant Professor of Chemistry David W. Wright, Professor of Pharmacology and Psychiatry Elaine Sanders-Bush, Allan D. Bass Professor of Pharmacology Randy Blakely and Stephen Pennycook, a condensed matter sciences division researcher at Oak Ridge National Laboratory (ORNL). Sanders-Bush and Blakely are also investigators at the Vanderbilt Kennedy Center for Research on Human Development.
Currently, nanocrystals are being made commercially, and there are a number of research groups who are trying to exploit their potential for the study of basic cellular processes. The Vanderbilt/ORNL group is one of the few that are developing this technology specifically to study nerve cells. Their goal is to develop a powerful new imaging technology that can accurately map different structures on the cell surface. These include receptors, ion channels and transporters. Receptors are specialized proteins that protrude above and below the cell membrane enabling them to bind to specific molecules in the surrounding environment and trigger specific biochemical actions within the cell. Ion channels are protein complexes that control the diffusion of sodium, calcium, potassium and other critical ions into and out of the cell. Transporters are special protein pumps that help reset neurons by vacuuming neurotransmitter molecules out of their synapses.
For more news about Vanderbilt research, visit Exploration, Vanderbilt’s online research magazine at www.exploration.vanderbilt.edu.
Media contact: David F. Salisbury, (615) 322-NEWS
David.salisbury@vanderbilt.edu