Meeting Abstract

120-1  Monday, Jan. 7 10:15 – 10:30  Embryonic Origins of Altered Ovarian Transcriptional Networks in an Environmental Model of Endocrine Disruption, the American Alligator HALE, MD*; MCCOY, JA; DOHENY, BM; GALLIGAN, TM; GUILLETTE, LJ; PARROTT, BB; University of Georgia; College of Charleston; University of Minnesota; Virginia Tech; Medical University of South Carolina; University of Georgia matthew.hale@uga.edu

The American alligator population inhabiting a contaminated Florida lake has served as a valuable environmental model for understanding the adverse effects of endocrine disrupting contaminants (EDCs) on reproductive development and heath. Using targeted approaches, previous studies have revealed persistent changes to ovarian transcription and suppressed responsiveness to gonadotropins in exposed individuals. In an effort to identify novel genetic pathways impacted by EDCs, we used an unbiased RNA-seq approach to describe transcriptional networks in the alligator ovary and the role of the embryonic environment in modulating responsiveness to FSH. Alligator eggs collected from the contaminated lake, Lake Apopka (AP), and a reference site, Lake Woodruff (WO), were hatched and raised for five months under laboratory conditions, then challenged with FSH or a vehicle control. We identify a suite of canonical FSH-responsive genes in both populations, including steroidogenic enzymes CYP11A and CYP17A, inhibins, and cyclin-related factors. Furthermore, we identify a strong influence of site in both non-challenged and challenged transcription; while populations share a suite of core responsive genes, each exhibits site-unique transcriptional responses. Additionally, approximately 12,000 genes in the non-challenged ovary differ by site, indicating a large degree of plasticity in ovarian function across populations. Collectively, these results suggest that developmental EDC exposure might play a substantial role in eliciting persistent transcriptional shifts in the ovary.