Meeting Abstract

P2.139  Wednesday, Jan. 5  DMRT1 as the potential male sex determining factor in the red-eared slider turtle (Trachemys scripta) a species with temperature-dependent sex determination BIESER, Kayla*; WIBBELS, Thane; University of Alabama Birmingham; University of Alabama Birmingham kbieser@uab.edu

Many reptiles possess temperature-dependent sex determination (TSD), in which the incubation temperature of the egg determines the sex of the hatchling. A number of potential sex determining genes are conserved among amniotic vertebrates, but none have been verified to be the sex determining switch. DMRT1 is a transcription factor that may regulate target genes triggering testis formation. In birds, the Z-linked gene DMRT1 has recently been implicated as the male sex determining gene, with knockdown expression of the gene resulting in genetic males becoming sex reversed. The current study investigates DMRT1 expression in the red-eared slider turtle, Trachemys scripta, using quantitative real-time PCR (RT-qPCR). This study included embryos that were incubated at both male- and female-producing temperatures. Additionally, embryos were sex reversed from female to male with the application of an aromatase inhibitor (Letrozole) and from male to female with the application of 17β-estradiol. Adrenal-kidney-gonad complexes were dissected from the embryos at developmental stages 15, 17, 19, 21, and 23 and prepped for RT-qPCR. The results provide an overview of DMRT1 expression during the thermosensitive period at both male and female producing temperatures as well as male to female and female to male sex reversal. The results also provide insight into the potential role of DMRT1 as a male sex determining factor during TSD in T. scripta.