FIGURE 1.

Isolation and characterization of Black Spot mutants. (A) Exemplar of the Black Spot phenotype. [1A13]/Df(3L)ED220 larvae exhibit melanotic nodules of various sizes; a particularly large one is labeled with an arrowhead (“BS”). (B–D) Complementation tests identified a collection of Black Spot mutants, only some of which actually generate melanotic masses with high penetrance (examples labeled with arrowheads). Normal (wt) animals complete their third instar larval stage by day ∼5, and proceed to ∼5 d of pupal development. Pupae containing pharate animals are visible by day ∼10, and they eclose shortly thereafter as adult flies. Wt animals are shown as a reference to the left of B and C. In contrast, many hemizygous Black Spot alleles are substantially developmentally delayed and maintain their larval phase until days 12 (C) to 16 (D), with some living mutants detected at day 18 (not shown). All of the larvae collected in this summary were mobile and thus alive. Hypomorphic mutants could pupate and even advance to the pharate stage; however, it is likely that some of the pupae shown at the latest days are deceased. See Supplemental Figure 1 for additional notes regarding the larval extended phase, lethal phase, and black spot penetrance at different ages in the different hemizygous mutants. (E) Several of the Black Spot mutants attain larger larval size than normal; shown are [1A13] hemizygotes as an example. Other alleles such as [f10978] are growth deficient. All alleles tested could be rescued by kae1 genomic transgenes; shown is rescue of [f10978]/Df larva.