A technique for introducing multiple fluorescent labels in vivo could deepen scientists’ understanding of the brain. Researchers at the University of Southampton injected mouse brains with a solution containing three viral vectors that produce red, green or blue fluorescent proteins. Different cell types took on different combinations of the proteins, giving each a characteristic watermark. This approach, called multicolor RGB tracking, allowed the researchers to color-code cells that otherwise would be undistinguishable. The marks are integrated into the DNA of each cell, and will be expressed forever in that cell and any daughter cells. “With this technique, we have proved the effective spatial and temporal tracking of neural cells, as well as the analysis of cell progeny,” said lecturer Dr. Diego Gomez-Nicola. “This innovative approach is primarily focused to improve neuroscience research, from allowing analysis of clonality to the completion of effective live imaging at the single-cell level.” The same approach could be used to change the expression of target genes for therapeutic purposes, the researchers said. “Multicolor RGB marking could serve as a universal and reproducible method to study and manipulate the (central nervous system) at the single-cell level, in both health and disease,” the researchers wrote in a paper published in Scientific Reports (doi:10.1038/srep07520 [open access]). Funding came from the Medical Research Council, the European Union and Wessex Medical Research. For more information, visit www.southampton.ac.uk.