The genomic region coding for amino acids 2 through 315 of 321 amino acids was replaced with an inframe human cDNA with the nucleotide substitution resulting in the amino acid substitution of arginine for histidine at position 134 (H134R) fused to Venus and followed by a floxed self-excising neo cassette. Expression of the fusion protein in nonpeptidergic neurons was confirmed by immunohistochemistry.