Articles from Sexual Development are provided here courtesy of Karger Publishers. Evolution of sex chromosomes in Sauropsida. It is noteworthy that dihydrotestosterone and flutamide did not influence gene expression until stage 18, which corresponds to the stage when AR levels increased in embryos shifted to a female-producing temperature [ Rhen et al.
An endoplasmic reticulum protein, calreticulin, is transported into the acrosome of rat sperm. Key Words: Genotypic sex determination, Gonad, Molecular genetics, Temperature-dependent sex determination. J Exp Zool. Gen Comp Endocrinol.
We have confirmed that temperature influences expression of these genes using independent biological samples and quantitative PCR using the methods described in Rhen et al. Other studies demonstrate that androgens promote early follicular growth in various species. Extra care should be taken in the design of experimental controls when compounds developed for mammals are used in reptiles.
Crews and colleagues  pioneered this procedure to administer estrogens to the developing embryo.
Sex determination in reptiles. The majority of WILD2 offspring were euthanized upon completion of metamorphosis or at day Aromatase activity levels during the thermosensitive period TSP are regulated by the temperature of the environment and control gonadal differentiation. References Mittwoch U.
We next explore whether this homology extends to the molecular level. Of the various genes so far associated with sex determination in other species, amphibians appear to express DMRT1.
Analysis of variation within monophyletic groups i. Colocalization of WT1 and cell proliferation reveals conserved mechanisms in temperature-dependent sex determination. Next, we present some approaches that have the potential to accomplish these aims.