畜牧兽医学报 ›› 2007, Vol. 38 ›› Issue (2): 190-195.doi:

• 基础兽医 • 上一篇    下一篇

牛口蹄疫病毒受体通用亚基αv的基因克隆及分子特征

独军政;常惠芸;丛国正;邵军军;林彤;高闪电;刘湘涛;才学鹏;谢庆阁   

  1. 中国农业科学院兰州兽医研究所 家畜疫病病原生物学国家重点实验室 农业部畜禽病毒学重点开放实验室 国家口蹄疫参考实验室,甘肃 兰州 730046
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2007-02-25 发布日期:2007-02-25
  • 通讯作者: 独军政

Molecular cloning and characteristics of cDNA encoding bovine αv subunit for FMDV receptor

  • Received:1900-01-01 Revised:1900-01-01 Online:2007-02-25 Published:2007-02-25

摘要: 研究发现,4种整联蛋白αvβ1、αvβ3、αvβ6、αvβ8能够介导口蹄疫病毒感染自然宿主,其中αv是4种受体的共用亚基。本试验对牛口蹄疫病毒受体通用亚基αv基因进行了克隆测序并对其编码蛋白的二级结构进行了预测。结果显示,牛αv亚基基因的编码区含有3147个核苷酸,编码1048个氨基酸,其中信号肽由30个氨基酸组成,胞外域由957个氨基酸组成,跨膜区由29个氨基酸组成,胞浆域由32个氨基酸组成;在890和891位氨基酸之间有一个蛋白酶裂解位点(KR-D);胞外域含有13个潜在的糖基化位点(NXT/NXS)、2个Ca2+结合位点(DX[D/N]XDGXXD)、18个半胱氨酸残基。该基因在GenBank中的登录号为DQ871215。牛αv基因与猕猴、家鼠、犬、人、鸡的αv基因的核苷酸序列同源性分别为91.0%、85.7%、90.1%、91.2%、73.1%,推导的氨基酸序列同源性分别为94.7%、91.6%、96.3%、95.0%、81.6%。牛αv亚基存在复杂多变的二级结构,这是其具有多种生物学功能的分子基础,其中1-30位、988-1017位氨基酸区段疏水性较强,形成表面蛋白结构的可能性较差,分别是该亚基的信号肽和和跨膜区。本试验为进一步深入研究口蹄疫病毒与宿主细胞的相互关系奠定了基础。

Abstract: Foot-and-mouth disease virus(FMDV)has been showed to use four integrins, αvβ1, αvβ3, αvβ6 and αvβ8 as receptors to initiate infection. In this study, the bovine integrin αv gene was cloned from the lung tissue of healed cattle infected experimently with foot-and-mouth disease virus by RT-PCR, and compared the nucleotide and predicted amino acid sequence homology with the αv gene of other animals.The secondary structure of bovine αv protein was predicted by the biological softwares. The 3147bp cDNA of bovine integrin αv encodes a polypeptide of 1048 amino acids consisting of a 30-residue putative signal peptide, a 957-residue ectodomain, a 29-residue transmembrane domain, and a 32-residue cytoplasmic domain. The ectodomain contains 12 potential N-linked glycosylation sites(NXT/NXS), 2 calcium binding domains(DX[D/N]XDGXXD), 18 cysteine residues, and a proteolytic cleavage site located between amino acid residue 890 and 891(KR-D). The nucleotide sequence similarity of integrin αv between cattle and rheses monkey, house mouse, dog, human,chicken is 91.0%,85.7%,90.1%,91.2%,73.1%, and the amino acid sequence similarity is 94.7%,91.6%,96.3%,95.0% and 81.6% respectively.The secondary structure of bovine αv contains few α-helix and many β-sheet and β-turn regions.The hydropathic analyses of the polypeptide revealed two hydrophobic domains,the signal peptide(1-30aa) and transmembrane domain(988-1017aa).