Figure 1. Tools used to generate disease models.

(A) Crossing a fly line containing eye-targeted GAL4 to a fly line with one or more transgenes results in progeny that express the transgenes in the tissue of interest (e.g., the eye). (B) Targeting expression of the oncogenic isoform Ret^MEN2B to the eye results in a ‘rough eye’ phenotype, best observed with misplaced outer lenses. Genetic enhancers (left panel) lead to a more extreme phenotype including outgrowths, while genetic suppressors (right panel) bring the eye closer to its normally smooth lens array.

Data taken from [Read R, Cagan R, Unpublished Data].