Figure 2. Increased Pipe expression leads to an increase in the processing of Easter and Spätzle, but not to increased processing of Snake.

(A) Cuticle preparations of embryos from females expressing Snk-HA (left column), Ea-HA (middle column), and Spz-HA (right column), in the absence (top row) or presence (bottom row) of hsp70-pipe. Note that for each transgene, expression in females together with the hsp7-pipe transgene leads to the production of embryos with a more strongly ventralized phenotype.

(B) Processing of Ea-HA in embryos from females expressing the fusion protein in an otherwise wild-type background (lane 1 at left), in a wild-type background together with the hsp70-pipe transgene (lane 2) and in a pipe mutant background (pipe genotype = pipe¹/pipe³). The arrow followed by “z” indicates the position of the zymogen form of the protein. Note that the increase in Ea-HA processing observed in the presence of hsp70-pipe is detected as increased amounts of Ea-HA-X (asterix). No Ea-HA-X is detected in extracts of embryos from pipe mutant mothers.

(C) Processing of Spz-HA in embryos from females expressing the fusion protein in the absence (left lane) or presence (right lane) of the constitutively expressed hsp70-pipe transgene. The arrow followed by “z” indicates the position of the zymogen form of the protein, while the arrowhead followed by “c” indicates the position of the cleaved form of the protein.

(D) Processing of Snk-HA in embryos from females expressing the fusion protein in the absence (left lane) or presence (right lane) of the constitutively expressed hsp70-pipe transgene. The position of molecular weight markers, in kD, are shown at left. The arrow followed by “z” indicates the position of the zymogen form of the protein, while the arrowhead followed by “c” indicates the position of the cleaved form of the protein.