绵羊IGFBP-4基因的克隆及序列分析

Cloning and Sequence Analysis of IGFBP-4 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IGFBP-4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:IGFBP-4基因的CDS序列为777bp,编码258个氨基酸,与山羊、牛、人的CDS同源性分别为99%、98%、95%,氨基酸序列同源性分别为100%、98%、97%,Gen Bank登录号为EU882037.1;IGFBP-4基因的氨基酸分子量为27.9KD,理论等电点(p I)为7.10;进化分析显示与牛、山羊等哺乳动物关系较近,与鸡、鱼类等亲缘关系较远;IGFBP-4基因存在明显的疏水性区域和亲水性区域,有1个信号肽、12个磷酸化位点和2个N-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67.44%、22.48%、10.08%;三级结构分析显示存在IGFBP-N功能域序列和甲状腺球蛋白-Ⅰ型功能域。为进一步研究绵羊IGFBP-4基因的功能奠定基础。

In order to cloning the CDS sequence of IGFBP-4 gene and obtain bioinformatics analysis, researchers have cloned the whole CDS sequence of IGFBP-4 gene by using the RT-PCR method with Liangshan semi-fine wool sheep and made further efforts to analyse its sequences in bioinformatics. The results showed that the CDS sequence of IGFBP-4 gene was 777 bp, encoding 258 amino acids, being 99%, 98% and 95% respectively about CDS homology compared with goat, bovine and human, was EU882037.1 of GenBank accession number. The amino acid sequence analysis revealed that it＇s relationship was near mammals about cattle and goat while it was far with chicken, fish etc, its homology was 100%, 98% and 97% respectively Compared with bovine, human and rat, its molecular weight was 27.9 KD, isoelectric point was 7.10 with obvious hydrophobie and hydrophilic regions, a signal peptide, a transmembrane region,12 sites of phosphorylation, 2 sites of N- glycosylation. There were forecast that the random coil, o^- helix and 13- sheet region were 67.44%, 22.48%, 10.08% respectively in secondary structure, a IGFBP-N domain and a thyroglobulin- I type of domain were in tertiary structure. It was provide a scientific basis to further study the function of IGFBP-4 gene in sheep.