中文摘要：

microRNA对细胞的增殖和分化有着重要的调节作用，从大白猪（Susscrofa）基因组DNA上扩增microRNA-378．1前体序列，经XhoI酶切后回收相应片段，连接到pEGP—miR载体中，构建重组载体pEGP．miR-378-1，转染猪胎儿成纤维细胞系（PEF），通过荧光观察转染效率及报告基因的表达效率，利用实时荧光定量PCR（QRT．PCR）测定细胞内microRNA．378—1的表达活性。结果表明，成功地构建了重组载体pEGP．miR-378-1；荧光观察转染后的细胞，显示有较高的转染效率，报告基因有较高的表达效率；QRT．PCR结果显示，实验组和对照组microRNA．378—1表达显著提高，实验组和对照组细胞间差异极显著（P〈0．01）；为制备转基因动物研究microRNA．378—1功能提供技术平台。

英文摘要：

microRNA has an important regulatory role in cell proliferation and differentiation. The microRNA-378-1 precursor was amplified by PCR from Large White （Sus scrofa） genomic DNA and was digested by Xho I and then ligated into Xho I digested vector pEGP-miR to produce the recombinant vector pEGP-miR-378-1. This vector was transfected to porcine fetal fibroblasts cells （PEF, porcine embryo fibroblast） and its transfection efficiency and expression were detected by fluorescence observation and RT-PCR, respectively. The results showed that pEGP-miR-378-1 vector was constructed successfully with high transfection efficiency. Further RT-PCR results showed that the expression of microRNA-378-1 was increased significantly compared with control groups （P〈0.01）. This will provide technological platform for producing transgenic animals to further study the function of microRNA-378-1.