The Expression Patterns of Membrane Progestin Receptor α (mPRα) During Oocytes Maturation in Cynoglossus semilaevis

Abstract:

In this study we investigated the expression patterns of the mRNA and proteins of membrane progestin receptor alpha (mPRα) in different tissues and oocyte phases using quantitative real-time PCR (qRT-PCR), in situ hybridization, immunohistochemistry, and western blotting analysis. Mature tissue samples were collected from female half smooth tongue sole Cynoglossus semilaevis. After in vitro incubation with or without human chorionic gonadotropin (HCG), the levels of mPRα mRNA and proteins in the oocytes at different developmental stages were measured with qRT-PCR and western blotting analysis. It was shown that the highest level of mPRα mRNA appeared in Phase V oocyte of mature C. semilaevis. 20 IU/ml HCG promoted the mRNA and protein expression more effectively than 10 IU/ml HCG. This further implied that mPRα was involved in the regulation of oocyte maturation through guiding progesterone. The western blotting analysis confirmed that the expression of mPRα proteins was higher in the brain, pituitary, and ovary than in other tissues. These results indicated that mPRα could play certain roles in different tissues, especially the endocrine-related ones. Results of in situ hybridization and immunohistochemistry clearly showed that the mPRα mRNA and proteins were expressed on the oocyte membrane and the peripheral or bureaucratic structures of other organs. Our study enriched the knowledge about mechanisms of membrane receptor signal transduction.