Biology Seminar | Anyi Mazo-Vargas, PhD | George Washington University | The complex art of butterfly wing color patterning—From DNA to signals to diversity

NSF-Postdoctoral Research Fellow.
Abstract: A central aim of evolutionary developmental biology is to elucidate the connection between genomic features and the wide variety of forms and shapes in the natural world. By studying the evolution of butterfly wing color patterns - a two-dimensional, tractable system for developmental and functional genetics - I am making connections between genomes, key developmental signals, and the evolution of the stunning morphological diversity found in these insects. In particular, I tested Wnt gene functions in patterning butterfly wing color elements and characterized the regulatory architecture modulating the role of the WntA signaling gene. My findings show that WntA instructs the shape of color arrays in both butterflies and swallowtails, repurposing previously existing patterns, evolving new ones, and combining with additional Wnt signals to create complex outputs. Sequence analysis of open chromatin DNA regions reveals extensive conservation of the WntA regulatory landscape across nymphalids, with a notable exception in the morphologically-derived monarch butterflies. Individual CRE deletions consistently led to overlapping color pattern changes, most of which induced both WntA loss- and gain-of-function effects on the wing patterns, suggesting that morphological tuning involved the subtle tinkering of an array of deeply ancestral, multifunctional sequences. These results establish butterfly color patterns as an integrative system to investigate mechanisms of Wnt signal transduction, its regulation, and shape diversification.