新城疫病毒V4株L基因的克隆与序列分析

设计了 2对引物V4L1、V4L2和V4L3、V4L4 ,用RT PCR法对新城疫病毒 (NDV )V4克隆株的L基因进行了分段克隆。用V4L1、V4L2扩增出约 4 .1kb的V 4LA片段 ,用V4L3、V4L4扩增出约 3.5kb的V 4LB片段 ,分别对克隆出的 2个片段进行序列测定 ,并用DNAsis软件比较分析后进行拼接 ,得到长约 7.2kb、包含有NDVV4克隆株L基因全长的核苷酸序列。NDVV4克隆株L基因mRNA全长为 6 70 4bp ,拥有 1个 6 6 15bp的开放阅读框 ,推测其编码的氨基酸数为 22 0 4个。氨基酸同源性分析表明 :V4克隆株与HB92V4株L基因的同源性为 99.0 % ,与LaSota、B1、B1T(美国Takaaki分离株 )、BeaudetteC、Clone30、F4 8E9、SF0 2和ZJ1株的同源性为 94 .1%～96 .5 %。

Cloning and sequencing of L gene of Newcastle disease virus V4 strain

Primers V4L1 and V4L2 were designed and synthesized to ampify fragment LA 4.1 kb in length and Primers V4L3 and V4L4 were designed and synthesized to amplify fragment LB 3.5 kb in length. After the fragments LA and LB were amplified by RT-PCR, they were sequenced and analyzed (using) DNAsis software respectively. Complete nucleotide sequence of L gene of Newcastle disease virus (NDV) V4 strain was obtained by means of splicing the fragment LA with the fragment LB. The results indicated that the L gene 6 704 bp in length has a single opening read frame 6 615 bp in length and codes a polypeptide of 2 204 amino acids of NDV V4 strain. Comparison of amino acid sequence was carried out (between) sequence of the 2 204 amino acids of NDV V4 strain and those of the publish amino acids of 9 NDV strains, respectively. The results showed that the 2 204 amino acids of NDV V4 strain shared 99.0% homology with that of HB92 V4 strain and shared 94.1%-96.5% homology with those of the other strains.