This transgene contains the coding sequence for Cre recombinase, followed by a polyadenylation signal to terminate the fusion transcript immediately after the recombinase gene, inserted into the mouse genomic bacterial artificial chromosome (BAC) RP23-195O10 at the ATG transcription initiation codon of the vasoactive intestinal peptide receptor 2 gene so that expression of the recombinase is driven by the regulatory sequences of the mouse gene. (J:145110)