Figure 6. Expression of Hox genes in corto mutant embryos.

A. Anti-Ubx antibody staining of w¹¹¹⁸ embryos, or embryos depleted of maternal and zygotic Corto. Upper row, lateral view and lower row, dorsal view. (B) Dorsal view. In wild-type embryos (left), Ubx is expressed from parasegment PS5 to PS12 with a higher expression in PS6. In corto embryos (right), the anterior boundary of Ubx is not modified but Ubx is strongly downregulated in PS11 and PS12 (arrowheads) . Parasegment numbers are indicated in white and the anterior border of Ubx expression by arrows. B. Anti-AbdB antibody staining of w¹¹¹⁸ embryos, or embryos depleted of maternal and zygotic Corto. Upper row, close-ups of the ventral nerve chord. In wild-type embryos (left), Abd-B is expressed in a decreasing gradient from PS13 to PS10. In corto embryos (right), this gradient extends anteriorly to PS9 and PS8. Moreover, expression of Abd-B seems to be higher in PS13 to PS10. Lower row, dorsal view of whole mount embryos showing ectodermal Abd-B expression; note ectopic expression of Abd-B in anterior parasegments in corto mutant embryos (arrows).