Differentially expressed bands were cut out of the gel, extracted, and re-amplified as per the manufacturer's instructions RNAimage Kit. Mol Syst Biol. There were no significant differences in esr1 expression between XX and XY gonads throughout the experimental period Fig.
This sex-determining gene is seen throughout the vertebrates, where its expression in gonads correlates extremely well with the production of testes.
Gonadal sex differentiation in Alligator mississippiensisa species with temperature-dependent sex determination. Asterisks indicate statistical differences determined by Student t -test. Turtle species that display TSD are thought to follow one of two patterns of temperature dependence.
Other reptiles governed by GSD have a system, similar to one found in birds, with Z and W sex chromosomes. All crocodilians, most turtlesmany fishand some lizards exhibit TSD.
The levels in XX gonads showed a significant increase from 25 to 70 dah, but the levels in XY gonads changed little after 15 dah. Androgen receptor AR expression also increased in embryos shifted to the female-determining temperature, but the increase was delayed one day relative to the increase in aromatase and FOXL2 expression [ Rhen et al.
Dev Biol. Evolution and Development.
The Sry-related gene sox9 has been shown to have a conserved, sexually dimorphic expression pattern in vertebrate embryos, its expression being upregulated male-specifically in mammals and birds [ 5 , 42 , 43 ] and maintained in males but downregulated in females in reptiles [ 44 , 45 ].
Dev Dyn. The critical role of Dmrt1 in testicular differentiation in tilapia was confirmed by our earlier findings that estrogen-induced sex reversal in XX tilapia was accompanied by the disappearance of dmrt1 expression in gonads of the treated fish [ 21 ].
For example, sex in the fruit fly, Drosophila melanogaster , is determined by the ratio of numerator and denominator genes found on the X chromosomes and autosomes, respectively [ Cline, ].