On the basis of sequencing and analyzing of the whole M genes(encoding viral membrane antigen glycoprotein) of three Crimean Congo hemorrhagic fever viruses(CCHFV),the Chinese isolates(Xinjiang hemorrhagic fever virus...On the basis of sequencing and analyzing of the whole M genes(encoding viral membrane antigen glycoprotein) of three Crimean Congo hemorrhagic fever viruses(CCHFV),the Chinese isolates(Xinjiang hemorrhagic fever virus,XHFV),we first expressed the glycoprotein (GP) gene of the prototype human origin XHFV strain BA66019 in eukaryotic cells and investigated the expression profiles.Three eukaryotic expression plasmids were constructed starting from ATG 78 (the first start codon of the deduced entire XHFv GP precursor gene positioned between the 78 th ～80 th nucleotides),ATG 93 and ATG 3084 (the potential start codon for G1 precursor gene).The constructs were transfected to COS-7 cells and the expressed products were characterized as membrane-bound proteins which could induce cell fusion This was much more apparent for recombinant plasmid with ATG 3084 A recombinant baculovirus was further created harboring full length GP gene(starting from ATG 78 ) and the expression could also result in the membrane fusion as well as swelling of the infected Sf9 cells The insect cell expressed G1 was smaller in M W than natural G1 (approximately 67kD) on SDS-PAGE and no recombinant G2 band was detectable Western-blot only detected the native G1,while there was no specific corresponding band of recombinant G1 These data suggested that G1 was structurally and functionally important in XHFV and the glycosylation may have great influence on M W as well as antigenicity This study provides a foundation for the future study of viral pathogenesis ,antigenicity and immunity,that are the theoretical and experimental backgrounds for vaccine展开更多
In order to analyze the nucleoprotein (NP) gene of Crimean-Congo hemorrhagic fever virus (CCHFV), viral RNA was amplified by RT-PCR by using the proof-reading DNA polymerase to produce the complete NP gene. The PCR pr...In order to analyze the nucleoprotein (NP) gene of Crimean-Congo hemorrhagic fever virus (CCHFV), viral RNA was amplified by RT-PCR by using the proof-reading DNA polymerase to produce the complete NP gene. The PCR product was sequenced, analyzed for phylogenesis and cloned into the expression vector pET32a and the recombinant plasmid expressed in E.coli BL-21 with high yield. The primarily purified fused protein was used to coat ELISA plates for the detect antibodies. It was found the similarities between NP gene of BA88166 and other XHFVs in nucleotide level and amino acid contents were very significant, and the NP gene of BA88166 encoded a nucleoprotein with 482 amino acid and a deduced molecular weight (MW) of 54?kDa. Western blot assay showed that the fusion protein expressed in bacteria possessed good antigenicity. The results with ELISA for the detection of the human and animal sera collected in endemic areas were found to be in good accordance to the clinical diagnosis. It concluded that the relations of NP genes of XHFV BA88166 and other XHFVs appeared to be evolutionally close. The methodologies established in this study were accurate, specific, rapid and reproducible for the clinical examinations and epidemiological survey.展开更多
We constructed a plasmid that contains a small piece of DNA with two vaccinis promoters running in opposite directions——a promoter from a late gene encoding an 11 K polypeptide (P11) and a promoter from an early gen...We constructed a plasmid that contains a small piece of DNA with two vaccinis promoters running in opposite directions——a promoter from a late gene encoding an 11 K polypeptide (P11) and a promoter from an early gene encoding 25K(P25). These promoters were isolated from the Tian Tan strain of vaccinia virus and were flanked by the thymidine kinase (TK) sequence of the same virus. Genes encoding the hepatitis B virus surface antigen (HBsAg) and the Rscherichia coli β-galactosidase (LacZ) were inserted downstream of the 11 K and 25 K promoters respectively so that coexpression plasmids were constructed. Recombinant vaccinis Viruses were selected directly by picking blue plaques formed under overlaying agarose medium containing X-gal. HBsAg was expressed to high level by these recombinant viruses. These recombinant viruses showed reduced virulence on rabbit skin and induced anti-HBs after intrsdermal inoculation of rabbits.展开更多
文摘On the basis of sequencing and analyzing of the whole M genes(encoding viral membrane antigen glycoprotein) of three Crimean Congo hemorrhagic fever viruses(CCHFV),the Chinese isolates(Xinjiang hemorrhagic fever virus,XHFV),we first expressed the glycoprotein (GP) gene of the prototype human origin XHFV strain BA66019 in eukaryotic cells and investigated the expression profiles.Three eukaryotic expression plasmids were constructed starting from ATG 78 (the first start codon of the deduced entire XHFv GP precursor gene positioned between the 78 th ～80 th nucleotides),ATG 93 and ATG 3084 (the potential start codon for G1 precursor gene).The constructs were transfected to COS-7 cells and the expressed products were characterized as membrane-bound proteins which could induce cell fusion This was much more apparent for recombinant plasmid with ATG 3084 A recombinant baculovirus was further created harboring full length GP gene(starting from ATG 78 ) and the expression could also result in the membrane fusion as well as swelling of the infected Sf9 cells The insect cell expressed G1 was smaller in M W than natural G1 (approximately 67kD) on SDS-PAGE and no recombinant G2 band was detectable Western-blot only detected the native G1,while there was no specific corresponding band of recombinant G1 These data suggested that G1 was structurally and functionally important in XHFV and the glycosylation may have great influence on M W as well as antigenicity This study provides a foundation for the future study of viral pathogenesis ,antigenicity and immunity,that are the theoretical and experimental backgrounds for vaccine
文摘In order to analyze the nucleoprotein (NP) gene of Crimean-Congo hemorrhagic fever virus (CCHFV), viral RNA was amplified by RT-PCR by using the proof-reading DNA polymerase to produce the complete NP gene. The PCR product was sequenced, analyzed for phylogenesis and cloned into the expression vector pET32a and the recombinant plasmid expressed in E.coli BL-21 with high yield. The primarily purified fused protein was used to coat ELISA plates for the detect antibodies. It was found the similarities between NP gene of BA88166 and other XHFVs in nucleotide level and amino acid contents were very significant, and the NP gene of BA88166 encoded a nucleoprotein with 482 amino acid and a deduced molecular weight (MW) of 54?kDa. Western blot assay showed that the fusion protein expressed in bacteria possessed good antigenicity. The results with ELISA for the detection of the human and animal sera collected in endemic areas were found to be in good accordance to the clinical diagnosis. It concluded that the relations of NP genes of XHFV BA88166 and other XHFVs appeared to be evolutionally close. The methodologies established in this study were accurate, specific, rapid and reproducible for the clinical examinations and epidemiological survey.
基金Project supported by the National Natural Science Foundation of China.
文摘We constructed a plasmid that contains a small piece of DNA with two vaccinis promoters running in opposite directions——a promoter from a late gene encoding an 11 K polypeptide (P11) and a promoter from an early gene encoding 25K(P25). These promoters were isolated from the Tian Tan strain of vaccinia virus and were flanked by the thymidine kinase (TK) sequence of the same virus. Genes encoding the hepatitis B virus surface antigen (HBsAg) and the Rscherichia coli β-galactosidase (LacZ) were inserted downstream of the 11 K and 25 K promoters respectively so that coexpression plasmids were constructed. Recombinant vaccinis Viruses were selected directly by picking blue plaques formed under overlaying agarose medium containing X-gal. HBsAg was expressed to high level by these recombinant viruses. These recombinant viruses showed reduced virulence on rabbit skin and induced anti-HBs after intrsdermal inoculation of rabbits.
