Fig. 5. Loss of WntD function leads to expansion of a Dorsal target gene. The blue staining in all the panels is RNA in situ staining using an antisense snail probe. The brown staining in E and F is in situ staining using an antisense huckebein probe. (A) Sagittal view of a wild-type blastoderm. The bracket at the posterior end indicates the retracted expression from the pole. (B) Ventral view of a wild-type gastrula, showing the sharp pattern of snail in the lateral and posterior regions. (C) Sagittal view of a Df(3R)l26c blastoderm. The bracket and the arrow indicate the expanded staining in the posterior and anterior regions, respectively. (D) Ventral view of a Df(3R)l26c gastrula; the expanded staining is similarly indicated by the bracket and the arrow. (E,F) Double staining of snail and huckebein, showing their complementary patterns in the posterior region of a wild-type embryo but overlapping pattern in a Df(3R)l26c embryo. (G) Ventrolateral view of an embryo derived from Df(3R)l26c strain that also contained a transgenic wntD genomic construct. All embryos from this rescued strain showed snail expression identical to that observed in wild-type embryos. (H) Ventral view of another wild-type blastoderm, with a retracted posterior pattern. (I) Sagittal view of a wild-type blastoderm previously injected with wntD dsRNA, showing a slightly expanded posterior expression. (J) Ventral view of a wild-type blastoderm previously injected with wntD dsRNA. The posterior sharpening is not as obvious as in wild-type embryos injected with buffer alone.