Sexual selection is a major driver of evolution, often resulting in drastically different characteristics between males and females. Recently it has become clear that gene duplication is also a powerful contributor to evolutionary diversification. This research seeks to understand how young gene duplicates evolve sex-specific essential functions under sexually antagonistic selection. Males and females, while sharing most of their DNA, satisfy different functional requirements for reproduction and survival. Sexual selection on traits with a shared genetic basis can have opposing effects in the two sexes, causing sexual conflict (SC) that may reduce fitness until the conflict is resolved by new genetic changes. This project addresses the hypothesis that gene duplication is an effective mechanism to resolve sexual conflict, using the fruit fly as a convenient model organism. In pursuing these aims, postdocs, graduates, undergraduates and high school students will be trained in molecular and evolutionary biology. The project will also partner with the Illinois Mathematics and Science Academy to involve diverse high school students in the research through lectures and summer internships.
This project focuses on a pair of recently duplicated genes (Apl and Arts) in Drosophila that have opposing fitness effects in the two sexes. The functional evolution in the protein sequences will be characterized to understand the role of protein divergence in mitigation of sexual conflict. The ancestral gene from which Apl and Arts were derived will then be computationally reconstructed and experimentally synthesized. A series of engineered Drosophila strains will then be created using gene editing technology, with different versions of the synthesized ancestral gene replacing the wildtype gene locus which harbors Apl and Arts. Divergence in expression of constructs with different regulatory regions will reveal their role in mitigating sexual conflict. The generality of the duplication-mediated SC resolution model will be tested by examining a score of recent gene duplicates with sex complementary expression patterns using gene knockout and rescue analyses.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
