This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2018, Broadening Participation of Groups Under-represented in Biology. The fellowship supports a research and training plan for the Fellow that will increase the participation of groups underrepresented in biology. The Fellow will investigate the genetic mechanisms and evolutionary forces shaping the differences between males and females, which are fundamental to the origins and maintenance of biological diversity. The Fellow will leverage the natural variation in the chromosomes that determine male vs. female in geckos to test classic evolutionary theory. The chromosomes that determine male vs. female are specialized chromosomes that trigger male or female development, and occur in two major systems. In XX/XY systems like humans, XY individuals are male, but in ZZ/ZW systems, ZW individuals are female. This fundamental difference in inheritance has sparked major theoretical predictions about the contrasting genetic mechanisms and evolutionary pressures shaping XY versus ZW systems. The Fellow will use geckos, which have evolved XY and ZW systems multiple times, to examine untested classical predictions using a novel and state-of-the-art comparative approach. The Fellow will broaden student participation in bioinformatics activities that explore genome biology and computational science, and will develop networking opportunities for underrepresented students seeking international research experience.
XY/XX and ZW/ZZ chromosomes arise as recombination is suppressed between a pair of autosomes, which subsequently diverge from one another in sequence and expression. Theory predicts key differences in the evolution of XY and ZW chromosomes and the roles they play in adaptation, dimorphism and speciation. In geckos, XY and ZW systems have evolved independently upwards of 17 times. The Fellow will conduct a comparative analysis of XX/XY and ZZ/ZW chromosome evolution using multiple independently evolved gecko XY and ZW systems. The Fellow will test the role of chromosomal inversions in recombination suppression between these chromosomes, and how cessation of recombination differs between XY and ZW systems. Next, the Fellow will investigate how recombination, selection, and drift shape divergence in these chromosomes. Finally, the Fellow will study the evolution of XX/XY and ZZ/ZW biased gene expression and how this process differs between XY and ZW systems. Together, these studies build an integrated mechanistic view of XX/XY and ZZ/ZW chromosome evolution and the fundamental forces acting across the entire genome. The Fellow will develop cutting-edge skills in research, mentoring, and communication, and will engage diverse audiences in genome evolution and global research opportunities.
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.
