鹅细小病毒非结构蛋白B细胞线性抗原表位的鉴定及抗原表位区分子特性分析

Identification of linear B-cell epitopes on goose parvovirus non-structural protein and the gene sequence analysis

为进一步对鹅细小病毒(GPV)非结构(NS)蛋白B细胞线性抗原表位进行定位,本研究设计了覆盖NS1蛋白C末端453 aa～627 aa的7个长约30个氨基酸残基的重叠短肽,并进行了融合表达。蛋白质印迹分析结果表明,表达的融合蛋白NSb(485 aa～514 aa)、NSc(498 aa～532 aa)、NSd(523 aa～556 aa)、NSe(543 aa～573 aa)、NSf(564 aa～598 aa)和NSg(599 aa～627 aa)能够被GPV免疫的鹅血清识别。将抗原表位区推导氨基酸序列与GenBank中登录的12株GPV和番鸭细小病毒(MDPV)相应序列应用DNAMAN进行同源性比较,并构建了系统进化树。分析结果表明,GPV各株之间的同源性较高,但在强弱毒株和不同地区分离株中存在一定的差异。同时,GPV和MDPV的NS蛋白中可能存在共同的线性抗原表位区。

In order to determining the B-cell epitopes on the non-structural protein （NS） of goose parvovirus（GPV）, Seven DNA fragments were amplified by RT-PCR, and expressed in E. coli, which encoded 7 partially overlaying short peptides covering the C-terminal of NS protein （453aa to 627aa）. The western blot analysis results show that the NS protein linear B-cell epitopes were located on 485aa to 514aa, 498aa to 532aa, 523aa to 556aa, 543 to 573aa, 564aa to 598aa and 599aa to 627aa. The dcduced amino acid of epitope sequence was compared with those of 12 GPV and Muscovy duck parvovirus （MDPV） referenence strains in GenBank, and phylogenetic tree analysis showed that all the strains of GPV shared highly common identity compared with each other, but there were also some difference between different strains. Meanwhile, GPV and MDPV probably share the common epitopes.