Bombyx mori cytoplasmic polyhedrosis virus is one of the major viral pathogens for the silkworm. The immune response of silkworm to the virus infection is obscure. A phosphotriesterase-related protein gene of silkworm...Bombyx mori cytoplasmic polyhedrosis virus is one of the major viral pathogens for the silkworm. The immune response of silkworm to the virus infection is obscure. A phosphotriesterase-related protein gene of silkworm, Bombyx mori (BmPTERP) was found in our previous microarry analysis of the midgut infected with the virus. In the present study, we cloned and analyzed the full-length cDNA of BmPTERP gene by means of rapid amplification of complementary DNA ends (RACE) and bioinformatic analysis for exploring its functions in interaction between the silkworm and the virus. The nucleotide sequence of the gene is 1349-bp and contains a 131 bp 5’UTR and a 165 bp 3’UTR. The 1053 bp open reading frame encodes a 350 amino acid protein. The deduced protein contains specific hits of phosphotriesterase-related proteins and belongs to the amidohydrolase superfamily. RTPCR analysis revealed that BmPTERP gene was expressed in all the tissues tested, including midgut, hemocyte, gonad, fat body and silk gland. Real-time quantitative polymerase chain reaction analysis indicated that the relative transcript of BmPTERP gene in the infected midgut was 19.32 fold lower than that in normal midgut at 72 hours post inoculation.展开更多
A strain of Cytoplasmic polyhedrosis virus (CPV) was separated from the infected larva during the research of integrated pest management of Dendrolimus superans. The morphology bioassay histopathology andfield-test fo...A strain of Cytoplasmic polyhedrosis virus (CPV) was separated from the infected larva during the research of integrated pest management of Dendrolimus superans. The morphology bioassay histopathology andfield-test for this CPV were studied. The size of CPV is 0.16 μm ×1. 57μm and the virion is 16.0 nm × 58.1 nm.The Lc50 to the 3rd and 5th instar larva of Dendrolimus superans were 2.81 × 104 PlB/mL and 7. 17 ×104 PIB/mLrespectively. The polyhedrosis were formed after midgut of larva were infected for 72 h. A large amount of polyhedrosis was formed after 144 h. The mortality was more than 82% and average mortality was 84.62% when using1 .17× 10s PIB/mL virus suspension to control the pest in field test.展开更多
This paper reports the histological observation of larvae ofZethenia rufescentaria Motsch. after infection by ZrNPV. Histopathologic study revealed that ZrNPV were multiplied within the nuclear of fat body, epidermis ...This paper reports the histological observation of larvae ofZethenia rufescentaria Motsch. after infection by ZrNPV. Histopathologic study revealed that ZrNPV were multiplied within the nuclear of fat body, epidermis cell, midgut cell, tracheal matrix and blood cell. These cells showed obvious cytopathic effects. The nucleus of infected cells underwent swelled. Under electron microscope, virus and polyhedral of ZrNPV were clearly observed in these nucleus of infected cells. The nucleus of susceptible tissues were fulfilled with polyhedra after 70–140 h.展开更多
The dissolution of polyhedra of Mythimna separata nuclear polyhedrosis. virus by digestive fluid (pH11. 03) collected from the 5th instar M. separata larvae was studied in vitro. Observations were made at timed interv...The dissolution of polyhedra of Mythimna separata nuclear polyhedrosis. virus by digestive fluid (pH11. 03) collected from the 5th instar M. separata larvae was studied in vitro. Observations were made at timed intervals using phase contrast microscopy and scanning electron microscopy. Under phase contrast microscopy, the polyhcdra lost their refrigence by 5 minute exposure to the digestive fluid. After exposure to the fluid for 30 minutes, all of the PIBs were dissolved. Chages of the PIBs were also observed under scanning electron microscopy, after 5 minute exposure to the fluid, damaged PIBs and PIB-derived debris were seen. After 30 minute exposure, only remains of PIBs were found. The effect of M. separata digestive fluid on the infectivity of Ms NPV was examined by nconatcs bioassay. The results indicated that virions from Ms NPV-PIBs were rapidly inactivated after 15 minute exposure to digestive fluid and all of virions were non-infectious.展开更多
Bombyx mori cytoplasmic polyhedrosis virus(BmCPV)is a major pathogen of the economic insect silkworm,Bombyx mori.Virus‐encoded microRNAs(miRNAs)have been proven to play important roles in host–pathogen interactions....Bombyx mori cytoplasmic polyhedrosis virus(BmCPV)is a major pathogen of the economic insect silkworm,Bombyx mori.Virus‐encoded microRNAs(miRNAs)have been proven to play important roles in host–pathogen interactions.In this study we identified a BmCPV‐derived miRNA‐like 21 nt small RNA,BmCPV‐miR‐1,from the small RNA deep sequencing of BmCPV‐infected silkworm larvae by stem‐loop quantitative real‐time PCR(qPCR)and investigated its functions with qPCR and lentiviral expression systems.Bombyx mori inhibitor of apoptosis protein(BmIAP)gene was predicted by both target prediction software miRanda and Targetscan to be one of its target genes with a binding site for BmCPV‐miR‐1 at the 5′untranslated region.It was found that the expression of BmCPV‐miR‐1 and its target gene BmIAP were both up‐regulated in BmCPV‐infected larvae.At the same time,it was confirmed that BmCPV‐miR‐1 could up‐regulate the expression of BmIAP gene in HEK293T cells with lentiviral expression systems and in BmN cells by transfecting mimics.Furthermore,BmCPV‐miR‐1 mimics could up‐regulate the expression level of BmIAP gene in midgut and fat body in the silkworm.In the midgut of BmCPV‐infected larvae,BmCPV‐miR‐1 mimics could be further up‐regulated and inhibitors could lower the virus‐mediated expression of BmIAP gene.With the viral genomic RNA segments S1 and S10 as indicators,BmCPV‐miR‐1 mimics could up‐regulate and inhibitors down‐regulate their replication in the infected silkworm.These results implied that BmCPV‐miR‐1 could inhibit cell apoptosis in the infected silkworm through up‐regulating BmIAP expression,providing the virus with a better cell circumstance for its replication.展开更多
EcoR I-P fragment has been cloned from Autographa californica multiple nuclear polyhedrosis virus (AcMNPV) genomic DNA and used as a probe. 0.5-kb and 1.1-kb fragments including p10 gene from Bombyx mori nuclear polyh...EcoR I-P fragment has been cloned from Autographa californica multiple nuclear polyhedrosis virus (AcMNPV) genomic DNA and used as a probe. 0.5-kb and 1.1-kb fragments including p10 gene from Bombyx mori nuclear polyhedrosis virus (BmNPV) have been hybridized. The p10 ORF was located in the EcoR I-R fragment. Initiation codon ATG of p 10 from BmNPV has been mutated by PCR, and the ATG region became a Bgl II site. A novel transfer vector pBmAcPV-1 has been constructed using both the p10 5’-flanking region whose initiation codon ATG has been mutated with BmNPV and the p 10 3’-flanking region of AcMNPV. The vector can recombine with not only AcMNPV DNA to express foreign gene in Sf cells, but also BmNPV DNA to express foreign gene in Bm cells. CAT gene was expressed at high level in Bm cells under the control of the mutated p10 promoter of BmNPV.展开更多
Bombyx mori cytoplasmic polyhedrosis virus （BmCPV） is one of the major viral pathogens for the silkworm. To date, the molecular mechanism of BmCPV invasion has been unclear. We cloned the full length complementary ...Bombyx mori cytoplasmic polyhedrosis virus （BmCPV） is one of the major viral pathogens for the silkworm. To date, the molecular mechanism of BmCPV invasion has been unclear. We cloned the full length complementary （c）DNA which encodes the ubiquitin-activating enzyme El-domain containing proteinl （UbE1DC1） ofBombyx mori by using suppression subtraefive hybridization （SSH） and rapid amplification of com- plementary （c）DNA ends （RACE）. The full-length eDNA of UbE1DClgene is 1 919 bp, consisting of a 100 bp 5＇ untranslated region, a 637 bp 3＇ untranslated region and an 1 182 bp open reading frame （ORF）, encoding a 393 amino acid protein. The protein contained the THiF_MoeB_hesA_family domain, an adenosine triphosphate binding site, which belongs to the family of ubiquitin-activating enzyme El. Reverse transcription - polymerase chain reaction analysis from the silkworm tissues, namely silk gland, hemo- cyte, fat body, gonad and midgut revealed that UbE1DC1 was expressed in all the five tissues. The real-time quantitative polymerase chain reaction analysis indicated that the relative expression of UbE1DC1 in the normal midgut was approximately 9.78-fold of that in the BmCPV-infected midgut. It is implicated that UbEIDCI may play an important role in the interaction between the host and BmCPV invasion.展开更多
文摘Bombyx mori cytoplasmic polyhedrosis virus is one of the major viral pathogens for the silkworm. The immune response of silkworm to the virus infection is obscure. A phosphotriesterase-related protein gene of silkworm, Bombyx mori (BmPTERP) was found in our previous microarry analysis of the midgut infected with the virus. In the present study, we cloned and analyzed the full-length cDNA of BmPTERP gene by means of rapid amplification of complementary DNA ends (RACE) and bioinformatic analysis for exploring its functions in interaction between the silkworm and the virus. The nucleotide sequence of the gene is 1349-bp and contains a 131 bp 5’UTR and a 165 bp 3’UTR. The 1053 bp open reading frame encodes a 350 amino acid protein. The deduced protein contains specific hits of phosphotriesterase-related proteins and belongs to the amidohydrolase superfamily. RTPCR analysis revealed that BmPTERP gene was expressed in all the tissues tested, including midgut, hemocyte, gonad, fat body and silk gland. Real-time quantitative polymerase chain reaction analysis indicated that the relative transcript of BmPTERP gene in the infected midgut was 19.32 fold lower than that in normal midgut at 72 hours post inoculation.
文摘A strain of Cytoplasmic polyhedrosis virus (CPV) was separated from the infected larva during the research of integrated pest management of Dendrolimus superans. The morphology bioassay histopathology andfield-test for this CPV were studied. The size of CPV is 0.16 μm ×1. 57μm and the virion is 16.0 nm × 58.1 nm.The Lc50 to the 3rd and 5th instar larva of Dendrolimus superans were 2.81 × 104 PlB/mL and 7. 17 ×104 PIB/mLrespectively. The polyhedrosis were formed after midgut of larva were infected for 72 h. A large amount of polyhedrosis was formed after 144 h. The mortality was more than 82% and average mortality was 84.62% when using1 .17× 10s PIB/mL virus suspension to control the pest in field test.
文摘This paper reports the histological observation of larvae ofZethenia rufescentaria Motsch. after infection by ZrNPV. Histopathologic study revealed that ZrNPV were multiplied within the nuclear of fat body, epidermis cell, midgut cell, tracheal matrix and blood cell. These cells showed obvious cytopathic effects. The nucleus of infected cells underwent swelled. Under electron microscope, virus and polyhedral of ZrNPV were clearly observed in these nucleus of infected cells. The nucleus of susceptible tissues were fulfilled with polyhedra after 70–140 h.
基金The project is supperted by National Natural Science Fundation of China
文摘The dissolution of polyhedra of Mythimna separata nuclear polyhedrosis. virus by digestive fluid (pH11. 03) collected from the 5th instar M. separata larvae was studied in vitro. Observations were made at timed intervals using phase contrast microscopy and scanning electron microscopy. Under phase contrast microscopy, the polyhcdra lost their refrigence by 5 minute exposure to the digestive fluid. After exposure to the fluid for 30 minutes, all of the PIBs were dissolved. Chages of the PIBs were also observed under scanning electron microscopy, after 5 minute exposure to the fluid, damaged PIBs and PIB-derived debris were seen. After 30 minute exposure, only remains of PIBs were found. The effect of M. separata digestive fluid on the infectivity of Ms NPV was examined by nconatcs bioassay. The results indicated that virions from Ms NPV-PIBs were rapidly inactivated after 15 minute exposure to digestive fluid and all of virions were non-infectious.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.31572463).
文摘Bombyx mori cytoplasmic polyhedrosis virus(BmCPV)is a major pathogen of the economic insect silkworm,Bombyx mori.Virus‐encoded microRNAs(miRNAs)have been proven to play important roles in host–pathogen interactions.In this study we identified a BmCPV‐derived miRNA‐like 21 nt small RNA,BmCPV‐miR‐1,from the small RNA deep sequencing of BmCPV‐infected silkworm larvae by stem‐loop quantitative real‐time PCR(qPCR)and investigated its functions with qPCR and lentiviral expression systems.Bombyx mori inhibitor of apoptosis protein(BmIAP)gene was predicted by both target prediction software miRanda and Targetscan to be one of its target genes with a binding site for BmCPV‐miR‐1 at the 5′untranslated region.It was found that the expression of BmCPV‐miR‐1 and its target gene BmIAP were both up‐regulated in BmCPV‐infected larvae.At the same time,it was confirmed that BmCPV‐miR‐1 could up‐regulate the expression of BmIAP gene in HEK293T cells with lentiviral expression systems and in BmN cells by transfecting mimics.Furthermore,BmCPV‐miR‐1 mimics could up‐regulate the expression level of BmIAP gene in midgut and fat body in the silkworm.In the midgut of BmCPV‐infected larvae,BmCPV‐miR‐1 mimics could be further up‐regulated and inhibitors could lower the virus‐mediated expression of BmIAP gene.With the viral genomic RNA segments S1 and S10 as indicators,BmCPV‐miR‐1 mimics could up‐regulate and inhibitors down‐regulate their replication in the infected silkworm.These results implied that BmCPV‐miR‐1 could inhibit cell apoptosis in the infected silkworm through up‐regulating BmIAP expression,providing the virus with a better cell circumstance for its replication.
基金Project supported by the 8th Five-Year Plan Research Program of China.
文摘EcoR I-P fragment has been cloned from Autographa californica multiple nuclear polyhedrosis virus (AcMNPV) genomic DNA and used as a probe. 0.5-kb and 1.1-kb fragments including p10 gene from Bombyx mori nuclear polyhedrosis virus (BmNPV) have been hybridized. The p10 ORF was located in the EcoR I-R fragment. Initiation codon ATG of p 10 from BmNPV has been mutated by PCR, and the ATG region became a Bgl II site. A novel transfer vector pBmAcPV-1 has been constructed using both the p10 5’-flanking region whose initiation codon ATG has been mutated with BmNPV and the p 10 3’-flanking region of AcMNPV. The vector can recombine with not only AcMNPV DNA to express foreign gene in Sf cells, but also BmNPV DNA to express foreign gene in Bm cells. CAT gene was expressed at high level in Bm cells under the control of the mutated p10 promoter of BmNPV.
文摘Bombyx mori cytoplasmic polyhedrosis virus （BmCPV） is one of the major viral pathogens for the silkworm. To date, the molecular mechanism of BmCPV invasion has been unclear. We cloned the full length complementary （c）DNA which encodes the ubiquitin-activating enzyme El-domain containing proteinl （UbE1DC1） ofBombyx mori by using suppression subtraefive hybridization （SSH） and rapid amplification of com- plementary （c）DNA ends （RACE）. The full-length eDNA of UbE1DClgene is 1 919 bp, consisting of a 100 bp 5＇ untranslated region, a 637 bp 3＇ untranslated region and an 1 182 bp open reading frame （ORF）, encoding a 393 amino acid protein. The protein contained the THiF_MoeB_hesA_family domain, an adenosine triphosphate binding site, which belongs to the family of ubiquitin-activating enzyme El. Reverse transcription - polymerase chain reaction analysis from the silkworm tissues, namely silk gland, hemo- cyte, fat body, gonad and midgut revealed that UbE1DC1 was expressed in all the five tissues. The real-time quantitative polymerase chain reaction analysis indicated that the relative expression of UbE1DC1 in the normal midgut was approximately 9.78-fold of that in the BmCPV-infected midgut. It is implicated that UbEIDCI may play an important role in the interaction between the host and BmCPV invasion.
