Fig. 5. torso-nos3'UTR can activate transcription of tailless-lacZ in early pole cells. Wild-type or torso-nos3'UTR females were mated to males carrying the tll:lacZ transgene. Embryos were co-immunostained with anti-Vasa (green) and anti-ß-galactosidase antibodies (red). All images show embryos at cycle 10. Wild-type embryo labeled with (A) both the antibodies or with (A') ß-galactosidase antibody. torso-nos3'UTR embryo labeled with (B) both antibodies or (B') only with ß-galactosidase antibody. Little or no ß-galactosidase is observed in the wild-type embryo, while a low but clearly detectable level of ß-galactosidase is evident in the torso-nos3'UTR embryos.