西藏小型猪Leptin及其受体胞外区片段的克隆及原核表达

目的 克隆及原核表达西藏小型猪瘦素(Leptin)成熟肽及瘦素受体胞外区片段.方法 根据西藏小型猪瘦素序列(GenBank号:GQ240885.1)和猪瘦素受体基因胞外域序列(GenBank号:AF167719.1)分别设计并合成两对引物扩增瘦素、瘦素受体基因胞外域编码区1654-2319位片段,以西藏小型猪组织总RNA为模板,经反转录-聚合酶链反应(RT-PCR)方法获得了特异性片段.再以该两个特异性片段为模板,另外设计两对带有BanH Ⅰ和HidⅢ酶切位点的套式引物分别扩增瘦素64-504位(成熟肽编码区)和瘦素受体基因胞外域编码区1655-2314位的cDNA片段,将该两片段克隆入pMD<,18>-T载体并转化感受态细菌E.coli DH5α测序并永久保存.此两片段经酶切后克隆到表达载体pRSET A的BamH Ⅰ和HindⅢ两酶切位点之间,构建重组质粒pR-OB和pR-OBR-a并在大肠杆菌E.coli BL21(DE3)中表达,SDS-PAGE电泳鉴定表达产物.结果 在IPTG诱导下促使重组菌pR-OB表达了相对分子质量约18×10<'3>左右的融合蛋白;重组菌pR-OBR-a表达了相对分子质量约27×10<'3>左右的融合蛋白.结论 说明重组质粒pR-OB、pR-OBR-a在大肠杆菌BL21(DE3)中分别可表达西藏小型猪瘦素成熟肽、瘦素受体片段蛋白,为进一步研究瘦素、瘦素受体功能和应用提供了基础.

Molecular Cloning and Prokaryotic Expression of Leptin and a Partial Leptin Receptor Extracellular Domain in Tibet Minipig

Objective To clone the prokaryotic expression of leptin mature peptide and a partial leptin receptor extracellular domain in Tibet minipig.Methods Two pairs of primers,amplifying the 64-504 bp leptin mature peptide coding region,and 1654-2319 bp leptin receptor(OBR) extracellular domain(ECD),were designed and synthesized according to the sequences of swine leptin(GenBank No.GQ240885.1) and OBR(GenBank No.AF167719.1) genes.Total RNA was extracted from the Tibet minipig liver tissue,and was used as the templa...