This transgene consists of a 2.2 kb fragment of the human GFAP promoter, a cDNA encoding a fusion of cre and the ligand binding domain of the human estrogen receptor modified to bind 4-hydroxytamoxifen, but not endogenous estrogen, an IRES, a cDNA encoding beta-galactosidase, and SV40 intronic sequence and polyadenylation signal. Transgene expression, assessed by beta-gal activity, is seen in Bergmann glia, neuronal precursors in the dentate gyrus, and cells in the subventricular zone surrounding the lateral ventricle. When crossed to reporter mice occasional tamoxifen-independent Cre mediated recombination is seen primarily in Bergmann glial cells. (J:140270)