Bulk electroporation of retinal ganglion cells in live Xenopus tadpoles.

Individual neurons in the developing nervous system of Xenopus laevis can be visualized by the targeted delivery of a fluorophore. The fluorophore can be delivered as a fluorescent dye or DNA that encodes a fluorescent protein. Local iontophoresis is a method that works well for transfer of fluorescent dye to retinal ganglion cells (RGCs) in the eye, but it does not give a high yield for delivery of DNA. This is largely because the degree of pigmentation of the eyes, even in albino strains, makes it difficult to visualize RGC somata during pipette positioning. Bulk retinal electroporation is a better approach for delivery of plasmid DNA to RGC. The method described here works best in tadpoles older than stage 42.