Figure 3.

An opus retrotransposon insertion 301 bp upstream of tube causes variable dorsalization. (A) Schematic of opus insertion site relative to the tube gene in the tub^var chromosomes. (B) Schematic of site-specific recombination technique used to map the mutation responsible for the variable dorsalization in the tub^ste chromosome. Schematic is not to scale. (C) Phenotypic data from site-specific recombination mapping of the tub^ste chromosome. Recombination was induced at a P-element insertion site located either 8 kb proximal (P) or 8 kb distal (D) to the tube gene. Phenotypes were assayed in embryos from females bearing the recombinant chromosome in trans to tub^null.