New fluorescent dyes allow visualization of neuronal membrane activity

Researchers at the University of California, San Diego School of Medicine have developed new fluorescent dyes that allow for the visualization of electrical activity in neuronal membranes. The new dye penetrate only the membrane of a cell and, when it is exposed to light, neuronal firings make the dye glow more brightly. “These results are the first demonstration of a new mechanism to sense membrane voltage,” says Roger Tsien, a UC San Diego professor of pharmacology and Nobel Prize recipient. The new dyes could lead to more accurate and efficient ways of studying voltage differences in the interior and exterior of neurons than what is currently used. “The new dye gives big signals but is much faster and doesn’t perturb the neurons,” explains Evan W. Miller, who is a post-doctoral researcher in Tsien’s lab. Analyzing these neuronal activities is critical to understanding the function of cells and the interactions between them.