The enhanced green fluorescent protein (EGFP) is fused to the 3' end of the gene, which carries a S193A (TCC->GCC) mutation, followed by an FRT-flanked PGK-neomycin selection cassette. Flp-mediated recombination removed the FRT-flanked neo cassette. GFP expression has been observed in cerebellar granule neurons, deep cerebellar nuclei, hindbrain nuclei, spinal cord interneurons, secretory intestinal cells, Merkel cells, and inner ear hair cells. (J:248783)