NSF Postdoctoral Fellowship in Biology FY 2017

Hook Kristin A, Takoma Park MD

Investigators

Abstract

This is an NSF Postdoctoral Research Fellowship in Biology, under the program Broadening Participation of Groups Underrepresented in Biology. The fellow, Kristin Hook, is conducting research and receiving training that is increasing the participation of groups underrepresented in biology, and is being mentored by Heidi Fisher at the University of Maryland (UM). The research explores the consequences of sperm cell shape on their function. Despite sharing a common goal to reach and fertilize an egg, sperm cells vary greatly. Rodent sperm are particularly diverse; not only do they vary within and across species, many feature a mysterious hook on their head, and a rare few exhibit collective behaviors in which they form aggregations of several cells that swim together. The significance of this variation is poorly understood. Using several species of deer mice, the fellow is exploring the relationship between sperm shape and their unique interactions. The research and training environment at UM is exceptionally diverse, with underrepresented minorities (URMs) comprising one-fourth of the student population. To broaden participation and engender an inclusive culture in biology, the fellow is collaborating with established university programs and local magnet schools to recruit and integrate URMs and women into lab and field research by providing hands-on training and mentorship. Moreover, the Fellow is sharing results of her research through (1) public talks on her research in both English and Spanish and (2) online platforms, including postings on her blog ("Animal Behavior Research Oddities") and Twitter. The fellow is characterizing how subtle morphological changes (e.g., minor differences in head shape) and extensive modifications (e.g., hook presence or absence) influence sperm interactions and swimming performance using a comparative, cross-species approach among species of deer mice (genus Peromyscus). She is also examining the biological relevance of sperm aggregates and identifying the genetic basis of the hook. The fellow is testing the hypotheses that (1) species with shared aggregate geometries exhibit similar sperm head geometries, (2) species with shared morphologies exhibit similar motility, (3) sperm aggregates enhance swimming performance, and (4) species lacking hooks do not form aggregates. Together this research advances our understanding of the evolution of reproductive traits, the molecular forces defining cell design, and the importance of sperm structure, which more broadly has implications for public health in identifying the unique cellular features contributing to sperm motility and, ultimately, male fitness.