动物营养学报2015，Vol.27Issue(12)：3920-3930,11.DOI:10.3969/j.issn.1006-267x.2015.12.034
催乳素和瘦素对奶牛乳腺上皮细胞乳蛋白及乳蛋白合成信号通路关键因子基因表达的影响
Effects of Prolactin and Leptin on Gene Expressions of Milk Proteins and Key Factors Related to Milk Protein Synthesis of Bovine Mammary Epithelial Cells
摘要
Abstract
This experiment was conducted to investigate the effects of prolactin and leptin on gene expressions of milk proteins and key factors related to milk protein synthesis of bovine mammary epithelial cells under pri-mary culture condition. The primary bovine mammary epithelial cells ( pBMECs) were cultured by collagenase digestion. The epithelial origin of pBMECs was identified by morphological observation, growth curve assay and specific milk protein gene expressions detection. There were four treatments with four concentrations of prolactin (0, 0.1, 1.0 and 10.0μg/mL, respectively), leptin concentration was the same (100 ng/mL), and each treatment had six replicates. Thiazole blue ( MTT) assay was used to detected the effects of prolactin and leptin on cells proliferation, and real time PCR was used to assay the effects of prolactin and leptin on gene ex-pressions of main milk proteins [α-casein,β-casein,κ-casein andβ-lactoglobulin (β-LGB) ] , Janus kinase 2 ( JAK2) , signal transduction and transcription activator 5 ( STAT5 ) and mammalian target of rapamycin ( mTOR) . The results showed that based on certain concentration of leptin ( 100 ng/mL ) , compared with 0 μg/mL prolactin treatment: the treatments of 0.1 and 1.0 μg/mL prolactin significantly promoted pBMECs proliferation (P<0.05); the treatments of 0.1 and 10.0 μg/mL prolactin significantly decreased the gene ex-pressions of αs1-casein, αs2-casein, β-casein and β-LGB(P<0.05); the treatment of 1.0 μg/mL prolactin significantly increased the gene expressions ofαs1-casein,κ-casein,β-LGB ( P<0.05);all supplemental treat-ments of prolactin exerted promotion effects on JAK2 gene expression ( P<0. 05 ); only the treatment of 1.0 μg/mL prolactin significantly increased STAT5 and mTOR gene expressions ( P<0. 05 ) . In conclusion, based on 100 ng/mL leptin in culture medium, positive effects of prolactin on gene expressions of milk pro-teins and key factors related to milk protein synthesis are observed, but the concentration should be limited in a certain range (0.1 to 1.0 μg/mL), and reverse inhibition effects emerge with high or low concentration. Our finding suggests that 100 ng/mL leptin and 1.0μg/mL prolactin show significant promotion effects on gene ex-pressions of milk proteins and key factors related to milk protein synthesis by regulating the gene expressions of signal factors of JAK2, STAT5 and mTOR.关键词
催乳素/瘦素/奶牛乳腺上皮细胞/乳蛋白基因/信号通路因子Key words
prolactin/leptin/bovine mammary epithelial cell/milk protein gene/signal pathway factor分类
农业科技引用本文复制引用
杜瑞平,王春艳,张兴夫,高民..催乳素和瘦素对奶牛乳腺上皮细胞乳蛋白及乳蛋白合成信号通路关键因子基因表达的影响[J].动物营养学报,2015,27(12):3920-3930,11.基金项目
国家自然科学基金(31060136) （31060136）
内蒙古农牧业科学院青年创新基金(2011QNJJM04) （2011QNJJM04）
