Isolation,Identification and Genetic Evolution of a Porcine Reproductive and Respiratory Syndrome Virus Strain Originated from Lineage 1 and 8 Recombination
In this study,a porcine reproductive and respiratory syndrome virus(PRRSV)strain was isolated from the lung of a sick pig suspected of PRRSV infection in Guangxi in 2023,and designated as GXWZ20230831.The complete genome was amplified using RT-PCR and sequenced to analyze its genetic e-volution.The results showed that GXWZ20230831 could proliferate in Marc-145 cells,exhibiting a marked cytopathic effect(CPE).The length of complete genome was 15 019 nucleotides(nt),showing the highest homology(94.0％)with PRRSV-2 NADC30-like strains,while it had the lowest homology(60.0％)with Lelystad virus,the representative strain of PRRSV-1.The alignment of Nsp2 amino acid sequence revealed 131(111+1+19)amino acid discontinuous deletions in GXWZ20230831,characteristic of the NADC30-like deletion pattern.Compared to the representative American strain VR2332,the GP5 protein of GXWZ20230831 exhibited three mutations in non-neutralizing epitopes:V27A,V185 A,and R191K.Addi-tionally,there were four potential N-glycosylation sites in the GP5 protein.Phylogenetic analysis of the whole genome sequence,nsp2 gene,and ORF5 gene indicated that GXWZ20230831 belongs to lineage 1.Re-combinant analysis revealed that GXWZ20230831 is a recombinant strain,with NADC30(a classical strain of lineage 1)as the backbone and lineage 8 strain providing the recombinant fragments.The recombination breakpoints were located in nsp1(458-1 821 nt)and nsp4(5 405-8 179 nt)of the genome.These findings provide an important scientific basis for understanding the infection status,genetic variation,and develop-ment of prevention and control measures for PRRSV in Guangxi.
PRRSVIsolation and identificationRecombinationGenetic evolution analysis
万方数据
维普
