绵羊IGFBP-7基因的克隆及序列分析

Cloning and Sequence Analysis of IGFBP-7 Gene in Sheep

试验以凉山半细毛羊为研究对象,采用RT-PCR方法克隆了其IGFBP-7基因的CDS全序列,生物信息学方法深入分析其序列。结果表明,凉山半细毛羊IGFBP-7基因的CDS序列为846 bp,编码282个氨基酸,与牛、人、鼠的CDS同源性分别为99%、95%、90%,氨基酸序列同源性分别为98%、93%、89%,Gen Bank登录号为FJ589640.1;IGFBP-7基因的氨基酸分子质量为29.0 ku,理论等电点(p I)为8.25;进化分析显示其与牛、山羊等哺乳动物关系较近,与斑马鱼、鲍等亲缘关系较远;IGFBP-7基因的蛋白质疏水性区域与亲水性区域间隔较为均匀分布,有1个信号肽、2个跨膜区、16个磷酸化位点、4个N-糖基化位点和1个O-糖基化位点;二级结构分析显示无规卷曲、α-螺旋和β-折叠区域分别为64.89%、19.86%、15.25%;三级结构分析显示存在IGFBP_N和Ig-like功能域。该试验为进一步研究绵羊IGFBP-7基因的功能奠定了基础。

The whole CDS sequence of IGFBP-7 gene was cloned from Liangshan semi-fine wool sheep and sequenced with RT-PCR and bioinformatics. The results showed that the CDS sequence of 1GFBP-7 gene was 846 bp, encoding 282 amino acids. Its CDS homology with bovine, human and rat was 99%, 95% and 90%, respectively. The registry number in GenBank was FJ589640.1. Analysis of the amino acid sequence revealed that it was close to mammals such as cattle and sheep and far from Haliotis diversicolor, fish, etc. Its molecular weight was 29.0 ku, with the theoretical isoelectric point of 8.25. The hydrophobic and hydrophilic regions in IGFBP-7 gene distributed uniformly. It had a signal peptide, two transmembrane region, 16 sites of phosphorylation, 4 sites of N-glycosylation and 1 sites of O-glycosylation. The analyses of secondary structure showed that the random coil, α-helix and β-sheet region were 64.89%, 19.86% and 15.25%, respectively. It had IGFBP_N domain and a Ig-like domain. It will provide a scientific basis for further studying on the function of 1GFBP-7 gene in sheep.