The Molecular Mechanism Of Dairy Goat Mammary Gland Epithelial Cells Apoptosis,Proliferation And Cell Cycle Regulated By PTHrP Through ΔfosB

Parathyroid hormone-related protein(PTHrP) may promote apoptosis or suppressed apoptosis under different circumstances. Δ-Finkel-Biskis-Jinkins murine osteosarcoma B(ΔfosB), as a member of activating protein-1(AP-1) family, which involving in a variety of cells’ s proliferation and differentiation, may also be involved in goat mammary epithelial cell proliferation and apoptosis process. Studies found that PTH(1-34) can induce expression fosB/ΔfosB, given that PTHrP having simil structrue and same receptor, we speculate that PTHrP may control the expression of ΔfosB. But the interactions between them in the apoptosis of dairy goat mammary gland epithelial cellsare still unknown.In the present study, we overexpressed or interferon expressed PTHrP or ΔfosB in dairy goat mammary gland epithelial cells, then test the mRNA expression of objective gene by real-time quantitative PCR, the cell proliferation by CCK-8 and microplate reader, the apoptosis and cell cycle by staining PI and flow cytometry. The study can accumulate data for molecular mechanism of goat mammary epithelial cell apoptosis in lactation and involution, and provide a theoretical foundation and experimental evidence to improve the milk production and quality of dairy goat.(1) PTHrP suppress the expression of ΔfosB after dairy goat mammary gland epithelial cells treated with Ad-PTHrP or Ad-PTHrP-322.(2) PTHrP and Δfos B can increase anti-apoptosis gene Bcl-2, Bcl-xL, proliferating cell nuclear antigen gene PCNA and cell cycle gene Cyclin D1 mRNA level and decrease pro-apoptosis gene Bax, p53 and caspase-3 m RNA level in dairy goat mammary gland epithelial cells, increase the ratios of Bcl-2/Bax, Bcl-xL/Bax, promote cell proliferation, increase the S and G2 state cells, suppress apoptosis after dairy goat mammary gland epithelial cells treated with Ad-PTHrP, Ad-PTHr P-322, Ad-ΔfosB or Ad-ΔfosB-572.(3) ΔfosB enhance the anti-apoptosis or pro-proliferation of PTHrP, when dairy go at mammary gland epithelial cells were treated with Ad-ΔfosB+Ad- PTHrP, Ad-ΔfosB+Ad-PTHrP-322, Ad-ΔfosB-572+Ad-PTHrP and Ad-ΔfosB-572+Ad-PTHrP-322.In conclusion, PTHrP may regulate dairy goat mammary gland epithelial cells proliferation, apoptosis and cell cycle through ΔfosB.