P74 is a per os infectivity factor of baculovirus.Here,we report the production of three monoclonal antibodies (mAbs),denoted as 20D9,20F9 and 21E1,raised against P74 of Helicoverpa armigera nucleopolyhedrovirus (Hear...P74 is a per os infectivity factor of baculovirus.Here,we report the production of three monoclonal antibodies (mAbs),denoted as 20D9,20F9 and 21E1,raised against P74 of Helicoverpa armigera nucleopolyhedrovirus (HearNPV),and the identification of their recognition epitopes.The full-length P74,without the transmembrane domains at the C-terminus,was first divided into three segments (N,M and C,respectively),based on the proposed cleavage model for the protein,which were then expressed individually.Western blot analyses revealed specific cross-reactions with the N fragment,for both 20D9 and 21E1.Extensive truncation,followed by prokaryotic expression,of the P74 N fragment was then performed in order to screen for linear epitopes of P74.The recognition regions of 20D9 and 21E1 were revealed to be localized at R144-T153 and T199-C219,respectively.In addition,immunofluorescence microscopy indicated that 20D9 and 20F9 could recognize native P74 in HearNPV-infected cells.These findings will facilitate further investigations of the proteolytic processing of HearNPV P74,and of its involvement in virus-host interactions.展开更多
Partial DNA sequences of three genes, that is, mitochondrial large ribosomal subunit (16S), nuclear large ribosomal subunit (28S D2) and mitochondrial NADH1 dehydrogenase (NADH1) gene, were sequenced from different mi...Partial DNA sequences of three genes, that is, mitochondrial large ribosomal subunit (16S), nuclear large ribosomal subunit (28S D2) and mitochondrial NADH1 dehydrogenase (NADH1) gene, were sequenced from different microgas trine species(Braconidae: Microgastrinae) collected fresh from paddy fields. The DNA sequences were used to determine the extent of sequence variation among species in order to evaluate the specific status of each species. Cladistic analysis was also used to infer a phylogenetic relationship among these species. The results showed that sequence divergence among species of the same genus Cotesia was much lower than those among different genera, such as Cotesia, Exoryza and Apanteles; the sequence similarity of 16S rDNA and NADH 1 genes between Cotesia sp. and C. chilonis was higher than that between C. sp. and C. ruficrus.Phylogenetic analyses suggested that four species of Cotesia were always grouped in the same clade regardless of using different analysis methods; Cotesia sp. and C. chilonis are more closely related to each other than to C. ruficrus, different from previous morphological results. Additionally, sequence analyses indicated that NADH1 gene has more parsimony informative characters than 28S rDNA D2 and 16S rDNA at the species-level analysis,indicating that NADH1 gene might be a useful marker for species-level analysis.展开更多
基金supported by the National Science Foundation of China(31130058 to Z.H.).Monoclonal Antibodies against HearNPV P74
文摘P74 is a per os infectivity factor of baculovirus.Here,we report the production of three monoclonal antibodies (mAbs),denoted as 20D9,20F9 and 21E1,raised against P74 of Helicoverpa armigera nucleopolyhedrovirus (HearNPV),and the identification of their recognition epitopes.The full-length P74,without the transmembrane domains at the C-terminus,was first divided into three segments (N,M and C,respectively),based on the proposed cleavage model for the protein,which were then expressed individually.Western blot analyses revealed specific cross-reactions with the N fragment,for both 20D9 and 21E1.Extensive truncation,followed by prokaryotic expression,of the P74 N fragment was then performed in order to screen for linear epitopes of P74.The recognition regions of 20D9 and 21E1 were revealed to be localized at R144-T153 and T199-C219,respectively.In addition,immunofluorescence microscopy indicated that 20D9 and 20F9 could recognize native P74 in HearNPV-infected cells.These findings will facilitate further investigations of the proteolytic processing of HearNPV P74,and of its involvement in virus-host interactions.
文摘Partial DNA sequences of three genes, that is, mitochondrial large ribosomal subunit (16S), nuclear large ribosomal subunit (28S D2) and mitochondrial NADH1 dehydrogenase (NADH1) gene, were sequenced from different microgas trine species(Braconidae: Microgastrinae) collected fresh from paddy fields. The DNA sequences were used to determine the extent of sequence variation among species in order to evaluate the specific status of each species. Cladistic analysis was also used to infer a phylogenetic relationship among these species. The results showed that sequence divergence among species of the same genus Cotesia was much lower than those among different genera, such as Cotesia, Exoryza and Apanteles; the sequence similarity of 16S rDNA and NADH 1 genes between Cotesia sp. and C. chilonis was higher than that between C. sp. and C. ruficrus.Phylogenetic analyses suggested that four species of Cotesia were always grouped in the same clade regardless of using different analysis methods; Cotesia sp. and C. chilonis are more closely related to each other than to C. ruficrus, different from previous morphological results. Additionally, sequence analyses indicated that NADH1 gene has more parsimony informative characters than 28S rDNA D2 and 16S rDNA at the species-level analysis,indicating that NADH1 gene might be a useful marker for species-level analysis.
