Fig. 2. Cos2 is necessary for the maintenance of Sxl expression. Embryos from cos2^w1/CyO, wg-lacZ stock triple stained for ß-gal (A), Sxl (B), and Msl-2 (C). Lack of wg-lacZ stripes identifies the homozygous mutant embryo which has very low levels of Sxl (compare to the wild-type female at the top) and expresses significant levels of Msl-2 but not equivalent to a wild-type male (lower left embryo).