Figure 4.

Demonstration of the establishment of the Hunchback gradient. (A) Nanos represses maternal hunchback (mhunchback) translation in the posterior end of the embryo, whereas Bicoid activates expression of zygotic hunchback (zhunchback). (B) The combination of repression of hunchback translation in the posterior end and the translation of both maternal and zygotic hunchback transcripts in the anterior end generates an anterior to posterior gradient of Hunchback. Brown pipe cleaners and beads represent bicoid transcripts and protein, respectively; green pipe cleaners represent mnanos transcripts; green beads represent nanos protein; red pipe cleaners represent mhunchback transcripts; red pipe cleaners with a black stripe represent zhunchback transcripts; and red beads represent hunchback protein.