The objective of this study was to construct the infectious clone of encephalomyocarditis virus (EMCV) BJC3 strain.The genomic cDNA of the virus was amplified by three overlapping segments using RT-PCR,and cloned into...The objective of this study was to construct the infectious clone of encephalomyocarditis virus (EMCV) BJC3 strain.The genomic cDNA of the virus was amplified by three overlapping segments using RT-PCR,and cloned into low-copy plasmid pWSK29 to construct the full-length cDNA clone pWSKBJC3/ w.The pWSKBJC3/w was in vitro transcribed and transfected into BHK-21 cells to rescue the virus.The results showed that the full-length cDNA clone was infectious and the virus could be rescued in BHK-21 cells.The rescued virus designated RvBJC3W was identified by RT-PCR and indirect immunofluorescence assay(IFA).The rescued virus had similar growth characteristics to its parental virus BJC3 and retained pathogenicity for mice.Our results indicate that the first infectious cDNA clone of EMCV in China has been successfully established and provides an essential tool for investigating the molecular basis of pathogenicity of EMCV.展开更多
Encephalomyocarditis virus(EMCV)is a positive single-stranded small RNA virus without envelope,which can infect a variety of mammals.Swines are the most susceptible animals,which can cause acute myocarditis and respir...Encephalomyocarditis virus(EMCV)is a positive single-stranded small RNA virus without envelope,which can infect a variety of mammals.Swines are the most susceptible animals,which can cause acute myocarditis and respiratory failure in piglets and reproductive failure in pregnant sows.Diseases caused by EMCV have a wide range of effects on the global swine industry.In this study,a strain of EMCV was isolated from a swine aborted fetus in northeast China.It was identified by reverse transcriptase polymerase chain reaction(RT-PCR),electron microscopic observation and indirect immunofluorescence assay.The subsequent results showed that the virus titer of HLJ strain grew to 8.3 lgTCID50 on baby hamster kidney 21(BHK-21)cells.And HLJ strain caused the specific cytopathic effect(CPE)on BHK-21 cells and severe pathological changes in mice.Complete genome sequencing and multiple sequence alignment showed that the homology between HLJ strain and other isolates worldwide was 71.5%-99.7%.Phylogenetic analysis showed that EMCV isolates fell into five clusters:lineageⅠ,Ⅱ,Ⅲ,ⅣandⅤ,based on the nucleotide sequences of the entire open reading frame(ORF)and VP1 gene.HLJ isolate was grouped into lineage I.The analyses of amino acid mutation sites of VP1 protein showed that the amino acids at positions 20 and 54 in VP1 junction were unique to HLJ strain.The isolation of HLJ strain enriched the epidemiological database of EMCV.展开更多
基金supported by the Key Project of National Natural Science Foundation of China(30530550)
文摘The objective of this study was to construct the infectious clone of encephalomyocarditis virus (EMCV) BJC3 strain.The genomic cDNA of the virus was amplified by three overlapping segments using RT-PCR,and cloned into low-copy plasmid pWSK29 to construct the full-length cDNA clone pWSKBJC3/ w.The pWSKBJC3/w was in vitro transcribed and transfected into BHK-21 cells to rescue the virus.The results showed that the full-length cDNA clone was infectious and the virus could be rescued in BHK-21 cells.The rescued virus designated RvBJC3W was identified by RT-PCR and indirect immunofluorescence assay(IFA).The rescued virus had similar growth characteristics to its parental virus BJC3 and retained pathogenicity for mice.Our results indicate that the first infectious cDNA clone of EMCV in China has been successfully established and provides an essential tool for investigating the molecular basis of pathogenicity of EMCV.
基金Supported by the National Natural Science Foundation of China(31372438)。
文摘Encephalomyocarditis virus(EMCV)is a positive single-stranded small RNA virus without envelope,which can infect a variety of mammals.Swines are the most susceptible animals,which can cause acute myocarditis and respiratory failure in piglets and reproductive failure in pregnant sows.Diseases caused by EMCV have a wide range of effects on the global swine industry.In this study,a strain of EMCV was isolated from a swine aborted fetus in northeast China.It was identified by reverse transcriptase polymerase chain reaction(RT-PCR),electron microscopic observation and indirect immunofluorescence assay.The subsequent results showed that the virus titer of HLJ strain grew to 8.3 lgTCID50 on baby hamster kidney 21(BHK-21)cells.And HLJ strain caused the specific cytopathic effect(CPE)on BHK-21 cells and severe pathological changes in mice.Complete genome sequencing and multiple sequence alignment showed that the homology between HLJ strain and other isolates worldwide was 71.5%-99.7%.Phylogenetic analysis showed that EMCV isolates fell into five clusters:lineageⅠ,Ⅱ,Ⅲ,ⅣandⅤ,based on the nucleotide sequences of the entire open reading frame(ORF)and VP1 gene.HLJ isolate was grouped into lineage I.The analyses of amino acid mutation sites of VP1 protein showed that the amino acids at positions 20 and 54 in VP1 junction were unique to HLJ strain.The isolation of HLJ strain enriched the epidemiological database of EMCV.