Figure 3. Schematic diagram of the Gr39a loci that are hypothesized to be alternatively-spliced. Grey boxes indicate the long alternatively-spliced N-terminal exons, while the three black boxes indicate the shared C-terminal exons. Two upstream exons present in pseudoobscura (1 and 5) were lost from Drosophila melanogaster (and D. yakuba), while one was duplicated in D. pseudoobscura (2/3).