Location And Expression Of E-Cadherin/Beta-Catenin In Mammary Epithelial Cells Of Dairy Cows

The mammary gland of dairy cows is a vital organ that controls the milk synthesis,secretion and lactation. The development of mammary gland requires cell adhersion and cell junction, including E-cadherin playing an important role in cell adhersions and the signals transduction. Nowadays, the structure and some related signals transduction pathways of mammary gland in development stages have not been studied comprehensively. On the basis of the structure and function of mammary gland research, the purpose of this study is to better understand and elaborate the molecular mechanisms and signal transduction of mammary gland in development process by molecular biology. In order to revel the mechanisms on molecular level, it provides some useful information for the construction and regulation of mammary development-lactation networks.In this study, Holstein dairy cows were used as the experimental animals, by using immunofluorescence triple staining technology, qRT-PCR and Western blotting, the expression of E-cadherin, Beta-catenin and Cycin D1at different development stages in dairy cow mammary gland tissue were detected. On the effect of Semen vaccariae and Taraxacu mogono, with dairy cow mammary epithelial cells culturing in vitro for model, cell adhesion molecules E-cadherin, Beta-catenin and Cycin D1mRNA and protein were detected by qRT-PCR and Western blotting, respectively. The RNA interference was used to knock down beta-catenin, and the expression of component members of the E-cadherin and Cyclin D1was subsequently examined. These could make better understand for the potential influence of adhersion molecules in Wnt signaling pathway of cow mammary gland.The results showed that in mammary gland of cows, E-cadherin, Beta-catenin and Cyclin D1were expressed in the different development periods, but expression were not consistent (P<0.05). The mRNA and protein level of E-cadherin, Beta-catenin and Cyclin D1were remarkably higher (P<0.05) after Semen vaccariae and Taraxacu mogono treatment. Using siRNA interference technology, a cell model about silencing beta-catenin gene was established successfully. The results of qRT-PCR and Western blotting, comparing with control group, showed that the mRNA and protein level of E-cadherin was decreased (P<0.05),on the country Cyclin D1increased obviously (P<0.05).It suggested that RNA interference Beta-catenin abnormally activated cell proliferation of the mammary gland of cows.In different development periods of mammary gland, E-cadherin, Beta-catenin and Cyclin D1expression were remarkable changed, suggesting that participated to regulation in mammary gland development and lactation of dairy cows. Semen vaccariae and Taraxacu mogono had a positive impact on the cell proliferation, they also have an effect on the adhesion molecules E-cadherin, Beta-catenin and Cyclin Dl. The Cyclin Dl gene had been shown to significantly higher after gene silencing of Beta-catenin. RNA interference Beta-catenin made us to understand better the role of Beta-catenin in Wnt signaling that played a critical role in mammary gland development.