摘要
为了解类NADC30猪繁殖与呼吸综合征病毒（PRRSV）在我国新的流行特点，本研究根据GenBank中美国2012年提交的PRRSV NADC30株全基因组序列设计合成8对引物，通过RT-PCR的方法对本实验室2016年从4个省搜集的临床样品中检测到的15株类NADC30 PRRSVs株进行了全基因组测序，并且结合参考株进行了序列分析。NSP2推导氨基酸的序列比对表明，15株PRRSVs均具有aa323～aa433＋aa484＋aa505～aa523 （111＋1＋19） 131个氨基酸缺失的分子特征；经RDP4和Simplot生物学软件分析表明，15株PRRSVs中14株为重组病毒株，参与重组的亲本病毒株为PRRSV NADC30株，提供重组基因片段的病毒株为HP-PRRSV或以VR2332为代表的经典PRRSV株，这些类NADC30重组病毒株的重组位置、重组的基因片段及重组片段长度均具有多样性，而且重组的位置多位于编码非结构蛋白或次要结构蛋白的基因区域；全基因组遗传演化分析表明，这些病毒株远离国内之前流行的HP-PRRSV，同源性仅为83.4 %～87.2 %，而与其它的类NADC30病毒株位于一个相对独立的分支，以上结果均表明这类病毒株已形成了一个新的亚群，命名为5亚群。本研究中不同地区PRRSV的核苷酸同源性差异较大，仅为88.6 %～99.6 %，并且只有2个病毒株可以感染PAM和MARC-145细胞。本研究表明，以基因缺失和基因重组多样性为主要特征的5亚群PRRSV已在我国流行，其生物学特性有待进一步研究。
To investigate the variant and genetic characteristics of NADC30-Like porcine reproductive and respiratory syndrome virus （PRRSV）, the full genomic sequences of 15 NADC30-Like PRRSVs were amplified by RT-PCR with 8 pairs of primers based on PRRSV NADC30 strain in GenBank, and sequenced for analysis. Deduced amino acid alignment showed that all the PRRSVs had the same 131 （111＋1＋19） amino acid deletions in the NSP2. Besides, recombination analysis with RDP4 and Simplot suggested that 14 out of 15 PRRSVs were the recombinant viruses based on NADC30-Like virus as the parental virus, and the recombination breakpoints were mainly in the genes coding non-structural proteins and minor structural proteins of the virus, which were integrated with various genes and different length of fragments from the HR-PRRSVs and the subgroup 1 PRRSVs represented by VR2332, respectively, displaying a polymorphism in the recombinant virus. Phylogenies of full genomes revealed that these NADC30-Like PRRSVs were far from the HP-PRRSV strains with 83.4% to 87.2% identity, and formed a new subgroup, named subgroup5. Howeve, the whole genome similarity of NADC30-Like PRRSVs from different regions had remarkable difference from 88.6% to 99.6%. Moreover, only 2 out of the 15 PRRSVs were able to infect and replicate in the PAM and MARC-145 cells. These data demonstrates that the subgroup5 is a now brunch of PRRSVs, characterized by 131 amino acid deletion and gene recombinant polymorphism, which currently prevails in China and the biological characteristics of the NADC30- Like PRRSVs need to be further studied.
出处
《中国预防兽医学报》
CAS
CSCD
北大核心
2016年第9期675-680,共6页
Chinese Journal of Preventive Veterinary Medicine
基金
国家自然科学基金(31270045)
国家自然科学基金(31502097)
关键词
猪繁殖与呼吸综合征病毒
类NADC30
缺失
重组
5亚群
porcine reproductive and respiratory syndrome virus
NADC30-Like
deletion
recombination
subgroup5
