Cre mediated recombination removes the loxP flanked STOP cassette from Gt(ROSA)26Sortm1(CAG-EGFP)Fsh. After removal of the FRT-flanked STOP cassette by Flp-mediated recombination, EGFP reporter expression is directed to the cells/tissues dependent upon the expression pattern of the promoter driving FLP recombinase. (J:155164)