NSF PRFB FY 2022: Uncovering the Influence of Hormone Signaling in Reptile Reproductive Development: Using CRISPR to Link Genotype, Phenotype, and Fitness

Kircher, Bonnie Katherine, Houston TX

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2022, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the fellow that will contribute to the area of Rules of Life in innovative ways. Hormones regulate many basic biological processes during development and adult life. Disruption of hormone actions at almost any stage of development and/or adult life leads to physiological alterations in many animals. Though hormones are well studied in some vertebrate species (e.g. mammals), little is known about their action in other vertebrate species. Lizards and snakes make up one of the most diverse vertebrate groups and have been well studied in the fields of evolution and ecology. Studies of reproductive organ formation in these animals have been neglected. This research leverages a novel gene manipulation technique in lizards to understand the role of hormones in male and female reptile biology and reproduction. Outreach collaborations with local organizations will provide resources for local communities to engage with reptile biology. The reproductive systems of vertebrates, although morphologically diverse, retain a fundamental organization and function across species, constrained by the pressure to reproduce. Studies in mice has demonstrated that the female and male reproductive system have a stereotypical intraspecific morphology, including the ovary, oviduct, uterus, and vagina in females and the testes, epididymis and vas deferens in males. The reproductive system in other vertebrate lineages has not been studied in a larger comparative context, limiting the ability to draw conclusions about reproductive organ homology. Steroid hormones, including androgens and estrogens regulate many aspects of development and function of the reproductive organs. The fellow will use recent advances in genome manipulation techniques (CRISPR/Cas) to generate estrogen and androgen receptor mutant brown anole lizards (Anolis sagrei). Morphological, 3D imaging, immunohistochemistry, and genomic methods will be used to assess anatomical and physiological differences between wild-type and mutant lizards. In addition, breeding assays will be used to determine the reproductive consequences of preventing steroid hormone signaling. These studies should lead to an understanding of conserved and diverse roles for this hormone action in vertebrates. Training and collaboration with students and faculty at the home institution along with a modern contribution of museums specimens for Anolis sagrei will ensure broad impact of this research. 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.