I 
Double staining of wild- type and hunchback-mw^aw? embryos, 
using an anti-Fushi tarazu (Ftz) antibody and a DGG-labeled 
probe for lacZ mRNA. 
1. The wild-type embryo exhibits a normal seven-stripe pat- 
tern of Ftz expression and shows the expression of a reporter 
lacZ gene in the anterior part of the embryo. This reporter gene 
is controlled by the hsplO TATA box promoter containing arti- 
ficial binding sites for both the bicoid and hunchback gene 
products. 
2. In the hunchback- mwtow? embryo, the pattern o/fushi tar- 
azu is disrupted in the anterior part, while the reporter is not 
affected. As discussed in the text, this points to a synergistic 
activation of the reporter gene by the product of the maternal 
gene bicoid and the maternal component o/hunchback. 
Research of Claude Desplan. 
114 
