Model Description: The R26-ZsGreen,-DTA allele is designed with a cre-dependent switch containing an ZsGreen sequence and an inverted DTA sequence that are uniquely flanked/separated by inward-facing lox sites (both lox2272 and loxP). Under control of the CAG promoter, widespread ZsGreen fluorescence is observed in the absence of Cre recombinase. Subsequent exposure to Cre recombinase that places DTA into the proper orientation to be expressed results in ablation of the cre-expressing cells.