四株不同宿主来源的Class I基因3型新城疫病毒全基因组序列测定及比较分析

为了解析基因型相同但宿主来源不同的新城疫病毒的全基因组差异。本文采用RT-PCR方法分别获得4株（JS/3/09/Ch，ZJ/3/10/Ch，AH/2/10/Du，JS/9/08/Go）Class I 基因3型病毒的全基因组核苷酸序列，并与GenBank中已公布的Class I基因3型病毒全基因组序列进行比对分析。本实验4株病毒的基因组长度均为15198bp，在基因组1607～1608位有6碱基的缺失，在2381～2382位有12碱基的插入，裂解位点为112EQ/RQE/GRL117是标准弱毒特征。5株Class I基因3型病毒之间全基因组同源性超过93%；而与Class II弱毒株同源性最低只有72.2%；比较6个结构蛋白基因的同源性，NP基因的同源性最高(98.3%～96.4%)，而P基因最低(96.1%～91.9%)。结果表明不同宿主来源的Class I基因3型新城疫病毒在遗传信息方面差异不大，但NP/F/L基因的变异幅度较P/M/HN基因明显。

Full-length Genome Analysis of Four Genotype 3 Letogenic Newcastle Disease Viruses Isolated from Different Hosts

The purpose of this study is trying to analysis the homology between four lentogenic Class I genotype 3 Newcastle disease virus isolates from different hosts with NDV strain NDV 08-004,which was the first obtained complete genome sequence virus of class I genotype 3.The full-length genome of NDV isolates,JS/3/09/Ch,ZJ/3/10/Ch,AH/2/10/Du and JS/9/08/Go,were determined by RT-PCR and then analyzed.All the genomes are 15 198 nucleotides(nt) in length.Compared with the full genome sequences of Class Ⅱ NDV stains(genotype Ⅳ-Ⅸ),four isolates has a 6-nt deletion in the non-coding region of nuclear phosphoprotein gene between nucleotides 1 640～1 641 and 12-nt insertion in the coding region of phosphoprotein gene between nucleotides 2 381～2 382.All the isolates have the motifs 112EQ/RQE/GRL117 at the cleavage site of the fusion protein,which is typical of lenogenic NDV strains,and it is in agreement with the result of pathogenic tests.The full-length genome of 4 genotype 3 NDV isolates shared 93% nucleotide identity with NDV08-004.The results of alignment of 6 viral genes showed that NP gene shared the highest identity(98.3%～96.4%) and P gene shared the lowest identity(96.1%～91.9%).The results show the following two points.First,it is concluded that the isolates from different hosts share the same genotype has the insignificant divergence in the genetic information.Second,it is proposed that the mutation rates of NP/F/L genes are lower than P/M/HN genes.