Effects of exogenetic trans-10, cis-12 cla on genes expression and protein synthesis of srebp-1 gene in bovine mammary epithelial cells | 外源反-10，顺-12共轭亚油酸对体外培养牛乳腺上皮细胞SREBP-1基因表达和蛋白质合成的影响

Chinese. 目的旨在观察反-10，顺-12，共轭亚油酸（t10c12 CLA）对牛乳腺上皮细胞中甾醇调控元件结合蛋白（SREBP-1）基因的表达和蛋白质加工的影响。方法本试验使用组织块培养法获得奶牛乳腺上皮细胞，使用不同浓度t10c12 CLA处理乳腺上皮细胞后，用油红染色法检测胞质内的脂滴分布，Trizol法提取细胞总RNA，荧光定量PCR法测定相关基因的表达量，试剂盒法提取细胞总蛋白，进行Western blotting。结果随t10c12 CLA添加量的增加，细胞质内甘油三酯的含量逐渐降低。与对照组相比，75、112.5和150 μmol#8226;L-1 t10c12 CLA均对胞质内甘油三酯的积累有显著抑制作用（P＜0.05）。t10c12 CLA 的添加对SREBP-1基因和参与SREBP-1蛋白加工调节基因的表达均无显著性影响（P＞0.05）。根据蛋白质电泳结果推测，t10c12 CLA对SREBP-1前体蛋白的合成并无影响，可能对SREBP-1的加工活化产生抑制作用或对其分解产生促进作用。结论t10c12 CLA能抑制胞质内甘油三酯的积累，对SREBP-1基因的表达、蛋白质翻译均无影响，可能影响其加工活化过程和活性蛋白的降解过程。

English. ObjectiveThe purpose of the study is to explore the effects of exogenetic t10c12 CLA on genes expression and protein synthesis of SREBP-1 in bovine mammary epithelial cells (BMECs). Method BMECs used in experiment were achieved by tissue culture methods. Lipids in cytoplasm were stained using oil red. The total RNA was extracted from BMECs treated with different gradients of t10c12 CLA. And then the expression levels of various genes were quantified by quantitative reverse transcription PCR (QRT-PCR) analysis. Total proteins extracted with protein extraction kit were used in SDS-PAGE and western blotting. ResultConcentration of cytosolic triacylglycerols (TAG) decreased linearly (P=0.0003) with the increasing t10c12 CLA concentration. The addition of t10c12 CLA had no effects on the expression of SREBP-1 gene and other genes related to post-translation process of SREBP-1 and the protein synthesis of precursor SREBP-1(pSREBP-1), maybe, it inhibited the synthesis or promoted the degradation of bio-active SREBP-1(bSREBP-1).ConclusionT10c12 CLA didn’t affect the gene expression and protein translation of SREBP-1 and inhibited cytosolic TAG accumulation. According to the results, it was speculated that t10c12 CLA maybe have some effects on activation of pSREB-1 and degradation of bSREBP-1.