Regulatory Switches in Drosophila
This animation shows how changes in the regulatory switch regions of a “paintbrush” gene lead to wing spot differences in Drosophila fruit flies.
The fly species Drosophila melanogaster and Drosophila biarmipes both have a “paintbrush” gene that controls pigmentation. As shown in the animation, only D. biarmipes also has a regulatory switch region that activates paintbrush gene expression in the wings. As a result, D. biarmipes has pigmented spots on its wings, and D. melanogaster does not.
This animation is a clip from a 2005 Holiday Lecture Series, Evolution: Constant Change and Common Threads. Depending on students’ background, it may be helpful to pause the animation at various points to discuss different features.
coloration, fruit fly, genetic switch, paintbrush gene, pigmentation, wing spot