Abstract:

In this study the expression profiles of 3β-HSD, P-450c17, P450arom and Estrogen receptor (ER) genes were analyzed to understand the potential influence of 3β-HSD, P-450c17, P450arom and Estrogen receptor (ER) on the early embryonic development and sex differentiation in quail embryo. The sexes of quail embryos were identified by PCR amplification of Wpkci gene, then 10 female and 10 male embryos at every time point (day 3, 4, 5, 6, 7 and 8 of incubation) of the early development stage were sampled. Real-time PCR was applied to analyze the expression profiles of 3β-HSD、P-450c17、P450arom and Estrogen receptor (ER) genes at different time points of the early development stage (day 3-8 of incubation) in quail embryos. Results showed that the expression levels of P-450c17, P450arom and ER were all higher in female than that in male on day 4 of incubation: for P450arom gene, it was detected only in female embryos throughout the incubation period and displayed the peaking level on day 4 of incubation（P<0.01）; for ER gene, the highest expression levels were detected on day 4 of incubation both in female and male, but the expression level in female was significantly higher than that in male （P<0.05）; for P-450c17, the expression level was higher in female than in male, but the difference was not significant（P>0.05）. The expression level of 3β-HSD gene was significantly higher in female than in male on day 5 of incubation（P<0.01）. These results indicate that 3β-HSD, P-450c17, P450arom and ER genes play an important role in the process of sex differentiation during the early development stage of quail embryo, especially at the day 4 to day 5 of incubation.