Years of research focused on the Drosophila eye and vertebrate retina have revealed, in fantastic detail, the molecular and developmental basis of vision. However, the molecular basis of visual attraction, i.e. the genes, molecular pathways, and neural circuits that integrate visual cues and direct a behavioral response towards a stimulus, has not been characterized as fully. Work on Heliconius butterflies has shown them to be primarily visual, with mate selection specifically mediated by simple visual cues. This project will utilize these unique features of Heliconius butterflies to characterize the fundamental biological process of visual mate choice. The research is likely to have a variety of broader impacts on science and society. Because divergence in color pattern and mate choice causes speciation in Heliconius butterflies, this research will provide an integrative analysis of the functional mechanisms responsible for the origin of species. Finally, a major educational outreach component of the project will implement new teaching and learning activities for students at secondary, undergraduate and graduate levels.
The fundamental goal of this research project is to characterize the molecular basis of visual mate choice spanning the continuum from organismal biology and behavior all the way to specific neural circuits and functional mutations. This will be achieved using three complementary research projects that integrate genomics, functional genetics, developmental biology, and comparative neurophysiology. Project 1 will generate a reference genome sequence and use genome resequencing data from preference-tested butterflies to map nucleotide changes responsible for divergent mate preference. Project 2 will characterize the developmental basis of visual preference by comparing patterns of gene expression between butterflies with divergent wing color and mate preference, focusing on wing, eye, and nervous system tissues, using a combination of qRT-PCR, in situ hybridization, and RNA-Seq. Project 3 will examine the anatomical and neurophysiological basis for mate preference, as well as functionally test genes associated with mate preference, using comparative analyses of eye anatomy, electrophysiology, and RNAi. All DNA and RNA sequence data will be deposited on the NCBI SRA database. Other data types will be stored locally and made available upon request.
