This transgene contains the mouse Defcr2 (defensin related cryptdin 2) promoter region (-6500 to +34) and the wild-type allele of the SV40 large T antigen (Tag) gene. Expression of the transgene is targeted to neuro-endocrine cells of the prostate gland. The Defcr2 promoter was originally observed to drive expression in Paneth cells of intestinal crypts and subsequently in prostatic epithelium. Eight lines were established but the references do not distinguish between them. Data may have been pooled from more than one line.