TARGETED ABLATION OF DIVERSE CELL CLASSES IN THE NERVOUS-SYSTEM IN-VIVO

The study of both the function and development of complex neural syste ms would be greatly facilitated by a means for systematically blocking intercell communication. One way of preventing cells from signaling e ach other is to remove them from the system by ablation. Here we prese nt a general technique for visualizing and ablating selected cell clas ses in vivo. The cells of interest are genetically engineered so that they can be selectively labeled with a photoactivatable dye and visual ized in living preparations; the dye-labeled cells can then be photoab lated. This approach is applicable to a broad range of cell types, in organisms amenable to gene transfer, and permits ablations to be perfo rmed at different developmental stages or in the adult. We demonstrate the use of this technique on several cell types in the mouse retina a nd cerebral cortex, and in the zebrafish embyro.