一株基因Ⅵ型鸭新城疫病毒F基因的克隆及序列分析

Cloning and Sequence Analysis of F Gene of a Genetype Ⅵ Newcastle Disease Virus Isolated from Duck

以一株鸭新城疫病毒NDV-SS分离株基因组RNA为模板,采用RT-PCR方法扩增其F基因,并进行克隆和序列测定。通过序列分析软件将该毒株F基因氨基酸推导序列与GenBank上已发表的新城疫病毒(Newcastle disease virus,NDV)F基因相关代表序列进行同源性及遗传进化关系分析。测序结果表明,NDV-SS株F基因全长1662bp,编码553个氨基酸,其蛋白裂解位点氨基酸序列为112R-R-Q-K-R-F117,符合NDV强毒株特有的序列结构特征。同源性及遗传进化关系分析结果表明,NDV-SS株为基因Ⅵ型毒株,与鸽源新城疫IT-227、Italy-2736分离株具有较高同源性和较近的亲缘关系,推测其可能是由鸽源新城疫病毒变异所产生的。

Using the genome RNA of NDV-SS strain of Newcastle disease virus （NDV） isolated from duck as a template,the F gene of NDV-SS strain was amplified by reverse transcription polymerase chain reaction （RT-PCR）. Then its gene cloning was completed,and its nucleotide sequence was determined. Nucleotide sequence homology and evolutionary processes analyses on amino acids sequence of F gene between SS strain and other NDV reference strains published in GenBank was executed using the sequence analysis soft. The F gene sequence of SS strain showed that NDV-SS strain was determined with its full-length of 1662 bp coding 553 amino acids. Amino acids sequence of F protein proteolytic cleavage position was 112R-R-Q-K-R-F117,indicated it is the virulent NDV strain.And the results of nucleotide sequence homology and evolutionary processes analyses showed that this strain belonged to the gene type Ⅵ,and had a close relationship with IT-227 and Italy-2736 strain. The presumable result was that this strain evolved from the NDV of pigeon origin.