An IRES-creER cassette, a tetracycline resistance gene and a Frt-flanked neomycin selection marker were all knocked in to the 3' UTR of the gene. The neomycin selection marker was removed by crossing to a C57BL/6 background Flp recombinase strain. Flp was then bred out of the line. When crossed with a Tg(CAG-Bgeo/ALPP)1Lbe reporter strain and given tamoxifen, cre expression was detected in a wide variety of neural and glial cells of the brain. This is line B4.