In all mammalian species, progesterone is essential in the preparation for and maintenance of pregnancy, if it occurs. Progesterone primes the endometrium for possible implantation and inhibits uterine contraction until birth. 20-alpha hydroxysteroid dehydrogenase (20α-HSD; EC.1.1.1.149) enzyme belongs to the family of aldo-keto reductases. 20α-HSD predominantly converts progesterone into its biologically inactive form 20α-hydroxyprogesterone (20α-OHP), and plays a crucial role in the termination of pregnancy and initiation of parturition. In addition, the activity of 20α-HSD during the luteal phase known to be inhibited by prolactin.
In this study, we focused on the analysis of transgenic mice expressing EGFP under control of monkey 20α-HSD promotor in mice testis. The protein expression and localization were detected by Western blotting and Immunohistochemical analysis, respectively. 20α-HSD protein was detected at molecular weight of 37-kDa by Western blotting analysis and EGFP was found at 27-kDa in the testis of TG mice. Also EGFP and 20a-HSD protein expression on 1, 2, 4, 6 and 8 weeks after birth were assessed. Both of them were increased the expression level time-dependently. 20α-HSD were strongly expressed in seminiferous tubule from 1 week after birth as seen in Immunohistochemical analysis. However, EGFP was strongly expressed in the seminiferous epithelial cells. Then, we determined the expression of EGFP mRNA in mice testis. Using primers specific for mouse EGFP, mRNA expression levels were analyzed by RT-PCR. The EGFP molecular weights is 400bp, qRT-PCR results using EGFP primer, The Cq value of the ratio decreased as the age increased. On this basis, mRNA were increased the expression level time-dependently.
In conclusion, these observations suggest that the 20α-HSD in testis could be play a pivotal role in the spermatogenesis.