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1.
The Douglas-fir tussock moth Orgyia pseudotsugata (Lepidoptera: Lymantriidae) is a frequent defoliator of Douglas-fir and true firs in western USA and Canada. A single nucleopolyhedrovirus (SNPV) isolated from O. pseudotsugata larvae in Canada (OpSNPV) was previously analyzed via its polyhedrin gene, but is phylogenetic status was ambiguous. Sequences of four conserved baculovirus genes, polyhedrin, lef-8, pif-2 and dpol, were amplified from OpSNPV DNA in polymerase chain reactions using degenerate primer sets and their sequences were analyzed phylogenetically. The analysis revealed that OpSNPV belongs to group II NPVs and is most closely related to SNPVs that infect O. ericae and O. anartoides, respectively. These results show the need for multiple, concatenated gene phylogenies to classify baculoviruses.  相似文献   

2.
The Douglas-fir tussock moth Orgyia pseudotsugata (Lepidoptera: Lymantriidae) is a frequent defoliator of Douglas-fir and true firs in western USA and Canada. A single nucleopolyhedrovirus (SNPV) isolated from O. pseudotsugata larvae in Canada (OpSNPV) was previously analyzed via its polyhedrin gene, but is phylogenetic status was ambiguous. Sequences of four conserved baculovirus genes, polyhedrin, lef-8, pif-2 and dpol, were amplified from OpSNPV DNA in polymerase chain reactions using degenerate primer sets and their sequences were analyzed phylogenetically. The analysis revealed that OpSNPV belongs to group II NPVs and is most closely related to SNPVs that infect O. ericae and O. anartoides, respectively. These results show the need for multiple, concatenated gene phylogenies to classify baculoviruses. Foundation item: Supported by a scholarship from the European Union (Functional Biodiversity and Crop Protection), contract no HPMT-CT-2000-00199.  相似文献   

3.
Monoclonal antibodies were produced to polyhedrins from Orgyia pseudotsugata multicapsid nuclear polyhedrosis virus (OpMNPV) and single-capsid nuclear polyhedrosis virus (OpSNPV). Although the polyhedrins are closely related, antibodies were selected which allowed differentiation between the two viruses. In an indirect enzyme-linked immunosorbent assay, purified OpMNPV and OpSNPV polyhedrins could be detected by specific monoclonal antibodies at concentrations as low as 2 and 5 ng/ml, respectively. The antibodies were also capable of identifying their homologous polyhedrin in extracts of infected insects. These antibodies would be useful for monitoring production of the viral insecticide, TM Biocontrol-1, which by license must contain only OpMNPV, and to confirm that insect mortality after aerial spraying with this insecticide is attributable to OpMNPV infection.  相似文献   

4.
Molecular characterization of a nucleopolyhedrovirus (NPV) isolated from the diseased larva of Orgyia ericae Germar was firstly analyzed. The genomic size of O. ericae NPV was estimated to be 134.6 kb by restriction endonuclease analysis. The gene encoding the major structural protein, polyhedrin, was cloned and sequenced. Phylogenetic analyses using polyhedrin sequences revealed that O. ericae NPV (OeNPV) was a member of the Group II NPVs and was closely related to the BusuSNPV and OpSNPV cluster. Electron microscopic observations confirmed that OeNPV was a single nucleocapsid type virus (SNPV).  相似文献   

5.
The satin moth Leucoma salicis L. (Lepidoptera, Lymantriidae) is a frequent defoliator of poplar trees (Populus spp.) in Europe and Asia (China, Japan). Around 1920 the insect was introduced into the USA and Canada. In this paper, a multicapsid nucleopolyhedrovirus isolated from L. salicis larvae in Poland (LesaNPV) was characterized and appeared to be a variant of Orgyia pseudotsugata (Op) MNPV. O. pseudotsugata, the Douglas fir tussock moth (Lepidoptera, Lymantriidae), occurs exclusively in North America. Sequences of three conserved baculovirus genes, polyhedrin, lef-8, and pif-2, were amplified in polymerase chain reactions using degenerate primer sets, and revealed a high degree of homology to OpMNPV. Restriction enzyme analysis confirmed the close relationship between LesaNPV and OpMNPV, although a number of restriction fragment length polymorphisms were observed. The lef-7 gene, encoding late expression factor 7, and the ctl-2 gene, encoding a conotoxin-like protein, were chosen as putative molecular determinants of the respective viruses. The ctl-2 region appeared suitable for unequivocal identification of either virus as LesaNPV lacked a dUTPase gene in this region. Our observations may suggest that LesaNPV, along with L. salicis, was introduced into O. pseudotsugata after introduction of the former insect into North America in the 1920s.  相似文献   

6.
茶尺蠖核型多角体病毒(EoSNPV)基因组的polh和egt基因区约14.2kb的酶切图谱被构建.egt基因位于polh基因上游约4.8kb处,但转录方向与polh基因相反.EcoRⅤ-L片段polh基因及其旁侧的1125核苷酸序列被测定.polh基因编码区长738核苷酸,可编码246氨基酸的多肽.起始密码子ATG上游是一个富含AT(AT占71.2%)的启动子区,在-52核苷酸处有杆状病毒晚期基因启动子转录起始基序ATAAG.在终止密码子下游208核苷酸有一个poly(A)信号,AATAAA.但EoSNPVpolh基因起始密码子ATG相邻核苷酸序列为GTAATGT,其-3是个G,这与已知的16种其它杆状病毒polh基因-3位置均是A不相同.在分析了EoSNPV和HaSNPV多角体蛋白基因核苷酸序列的基础上,通过MALIGN程序,比较了目前已发表的26种杆状病毒包涵体蛋白的序列,EoSNPV与黄杉毒蛾核型多角体病毒(OpSNPV)的同源性为最高,核苷酸序列的同源性为83.0%,氨基酸序列达94.7%;与其它20种鳞翅目NPV的同源性也很高,核苷酸序列同源性为72.6%~81.9%,氨基酸序列为83.7%~93  相似文献   

7.
核型多角体病毒(Nuclear Polyhedrosis Virus,简称NPV)的核多角体蛋白(Polyhedrin)基因具有一个非常强的启动子和基因调控序列。目前利用这一基因的上述序列已组建了多种表达载体,高效地表达了十几种外源基因产物,成为当前最有前途的新的表达系统。但是,在组建这一病毒载体过程中,为了使插入的外源基因靠近病毒启动子序列,各  相似文献   

8.
The first characterization of a nucleopolyhedrovirus (NPV Baculoviridae) isolated from the vapourer moth, Orgyia antiqua (Lepidoptera Lymatriidae), in the United Kingdom is presented. Transmission electron microscopy revealed that the virus nucleocapsid rods were singly enveloped in the polyhedron inclusion body (PIB) so that the virus is assigned to the SNPV subgenus of the Baculoviridae. Restriction endonuclease analyses of viral DNA indicated a genomic size of approximately 148 kb. Restriction profiles of O. antiqua SNPV closely resembled those of heterologous NPVs isolated from four different Orgyia species and was most similar to a North American SNPV isolate from the Douglas-fir tussock moth, O. pseudotsugata. In host range tests, O. antiqua SNPV was not infectious to 23 lepidopteran species representing four families. Heterologous Orgyia NPV isolates were permissive in O. antiqua larvae. Using a diet plug bioassay method, the median lethal dose response (LD(50)) for this virus in second and third instar O. antiqua larvae were estimated at 52 and 539 PIBs per larva, respectively.  相似文献   

9.
从东北林业大学实验林场采集并纯化了舞毒蛾核型多角体病毒(LdMNPV-NEFU)。用蛋白酶K消化,提取了病毒基因组DNA。用PCR方法,克隆出了该病毒的多角体蛋白(polyhedrin)基因,并对该基因进行了序列测定。结果显示,该基因序列是一个含有735个碱基对的开放阅读框(ORF),该阅读框编码245个氨基酸。有5对碱基与加拿大病毒株LdMNPV-G的多角体蛋白基因序列存在差异。LdMNPV-NEFU分离株的多角体蛋白基因的第54,109,379,508和701位(从起始密码子中的A开始)分别是C,G,T,C和G,而LdMNPV-G分离株的多角体蛋白基因(ORF)相应位置上的碱基分别是G,C,C,T和T,两个ORF编码的对应位置的氨基酸绝大多数相同,只有一对不同,即由LdMNPV-NEFU编码的天冬氨酸和由LdMNPV-G编码的对应位置的组氨酸。以质粒pT-7-7为载体,多角体蛋白基因在大肠杆菌BL21(DE3)菌株中进行了原核表达。  相似文献   

10.
Abstract  LdMNPV - NEFU isolate collected from the forestry farm of Northeast Forestry University was purified and the genomic DNA of MMNPV was extracted. The LdMNPV polyhedrin gene was cloned by PCR. The results showed that the sequence was an open reading frame (ORF) of 735bp capable of encoding 245 amino acids. The polyhedrin gene sequences of the MMNPV-NEFU isolate and a Canada strain, MMNPV-G differed in 5 bases. The polyhedrin gene of the LdMNPV-NEFU isolate contained C, G, T, C and G at 54, 109,379, 508 and 701 sites from the start codon, but the LdMNPV-G isolate contained G, C, C, T and T at the corresponding sites respectively. The same amino acids were encoded by the two ORF sequences, with the exception that Asp and His are encoded by GAC on the polyhedrin gene sequence of the LdMNPV-NEFU isolate and by CAC in the MMNPV-G isolate. The MMNPV polyhedrin gene was expressed in E. coli BL21 (DE3) by the pT7–7 plasmid vector.  相似文献   

11.
The insect growth regulator tebufenozide (MIMIC 2LV) was tested to examine its impact on the Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough) (Lepidoptera: Lymantriidae). Laboratory tests gave an estimated concentration of 1.26 ppm of the compound to achieve 50% population mortality (LC50) for second-instar O. pseudotsugata. At the highest concentration tested, tebufenozide resulted in significant larval mortality within 7 d with an estimated time to 50% population mortality (LT50) of 6.3 d. A field comparison oftebufenozide with diflubenzuron (Dimilin 4L) and Bacillus thurengiensis var. kurstaki (Btk, FORAY 48B) was also conducted. There was no significant difference in larval mortality within field plots that were treated with diflubenzuron (42.4%) or Btk (44.8%). Larval mortality in the tebufenozide-treated plots (56.8%) was also similar to the mortality in the diflubenzuron and Btk treatments. All three treatments resulted in more larval mortality than that measured in untreated controlplots (11.2%). Both tebufenozide and diflubenzuron treatments resulted in significantly more mortality (55.0% and 40.0%, respectively) to larvae-fed treated foliage 3 wk after application than was measured for larvae-fed foliage from untreated trees (11.0%). There was no significant difference among the treatments in the percentage of host trees in the overstory that sustained >25% defoliation, and all three treatments resulted in less defoliation than was measured in the control plots. There was no significant difference among the treatments in the percentage of host trees in the understory that sustained >25% defoliation.  相似文献   

12.
The Douglas-fir tussock moth (Orgyia pseudotsugata) multicapsid nucleopolyhedrovirus (OpMNPV) is periodically applied to suppress Douglas-fir tussock moth populations in British Columbia and in the western United States. The strain of OpMNPV in the product currently used for suppression is not genetically distinct from naturally occurring OpMNPV. To separate the mortality caused by the applied virus from that caused by the naturally occurring virus, a rare and genetically distinct strain of OpMNPV must be applied. To learn more about the genotypic diversity of OpMNPV populations in BC and to identify rare strains in this region, viral DNA was extracted from larvae reared from 208 field-collected egg masses found in five geographic regions of British Columbia and subjected to REN analysis. Nine, 12, and 9 different genotypes were detected using PstI, SalI, and HindIII, respectively. When the PstI, SalI, and HindIII profiles for each pure (single strain) isolate were grouped and considered as a combined PstI-SalI-HindIII genotype, 23 different genotypes were identified among 185 isolates. Nine rare OpMNPV genotypes were selected as ideal candidates for use as a potential 'marker strain' to accurately determine the efficacy of the treatment.  相似文献   

13.
Monochromatic radiation at wavelengths of 290, 300, 310, and 320 nm inactivated occluded nuclear polyhedrosis virus of the Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough). Data indicate that all of the wavelengths are capable of causing virus inactivation; much greater fluences are needed for virus inactivation as the wavelength increases.  相似文献   

14.
Monochromatic radiation at wavelengths of 290, 300, 310, and 320 nm inactivated occluded nuclear polyhedrosis virus of the Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough). Data indicate that all of the wavelengths are capable of causing virus inactivation; much greater fluences are needed for virus inactivation as the wavelength increases.  相似文献   

15.
为了表达马尾松毛虫质型多角体病毒(DpCPV)多角体蛋白基因(S10片段)并探讨多角体蛋白在真核细胞中的定位,从DpCPV中分离出S10,与pET-28a载体连接成重组表达质粒pET28-S10;将S10克隆到杆状病毒转座载体pFASTBACHTb中,依次筛选出重组转座质粒pFASTBACS10,重组穿梭质粒BacmidS10,重组杆状病毒AcS10。多角体蛋白基因表达后,用SDS-PAGE、Western-blot和免疫荧光技术对表达产物进行了检测。结果表明:S10原核表达质粒、重组杆状病毒成功获得;在昆虫细胞中表达的质型多角体蛋白主要定位于细胞质,同时有少量产物定位于细胞核。  相似文献   

16.
17.
K Iatrou  R G Meidinger 《Gene》1989,75(1):59-71
The polyhedrin gene of the nuclear polyhedrosis virus of the silkmoth Bombyx mori (BmNPV) has been subjected to deletion mutagenesis. A number of clones containing partially deleted polyhedrin genes were characterized and four clones containing limited deletions of the 5'-untranslated or 5'-flanking sequences of the gene were further analyzed with respect to polyhedrin promoter activity. The functional characterization of the deletion mutants was achieved through the insertion of a chloramphenicol acetyl transferase (CAT) gene (cat) into each deletion junction. The resultant cat constructs were introduced into the genome of BmNPV through homologous recombination and the effect of each deletion on the activity of the polyhedrin promoter was evaluated by measurements of CAT enzymatic activity in extracts of tissue culture cells infected with the corresponding recombinant BmNPVs as well as by primer extension assays. Removal of the entire leader region and eleven adjacent residues of the 5'-flanking sequences of the polyhedrin gene results in a dramatic decrease in promoter activity, which, however, remains detectable through CAT activity measurements. Elimination of an additional 30 nucleotides (nt) of the upstream sequences results in the complete inactivation of the polyhedrin promoter. The functional characterization of a deletion mutant lacking 41 nt of the 5'-flanking sequences has demonstrated that no functions necessary for viral infectivity, replication or assembly are disrupted by this deletion, since the corresponding recombinant viruses propagate in the cells with the same kinetics and to the same extent as wild-type BmNPV. As a result of the deletion mutagenesis, two classes of transfer vectors have become available. The first class can be used for introducing into the viral genome foreign nucleotide sequences under polyhedrin promoter control, while the second one can be used for obtaining recombinant viruses harboring foreign genetic material in an environment which is devoid of polyhedrin promoter activity.  相似文献   

18.
The use of previously published primers to amplify the monodon baculovirus (MBV) polyhedrin gene sequence by polymerase chain reaction (PCR) from post larvae (PL) of Thai Penaeus monodon resulted in failure. As a result, the putative polyhedrin protein of MBV was isolated from infected PL by homogenization, differential centrifugation and density gradient centrifugation with verification by transmission electron microscopy (TEM). By SDS-PAGE, a single major protein band at 58 kDa was obtained from the putative polyhedrin fraction and this corresponded to a previous report of the molecular weight of polyhedrin from MBV. When used for N-terminal sequence analysis, the putative polyhedrin protein yielded a sequence of 25 amino acids (M F D D S M M M E N M D D L S G D Q K M V L T L A) that did not correspond to the deduced amino acid sequence derived from a previous report of a putative MBV polyhedrin gene amplicon. Despite this, a synthetic peptide of our 25 amino acid sequence (25Pmbv) was conjugated with bovine serum albumin and used as an antigen for antiserum production in mice. Using immunohistochemistry with tissue sections of PL infected with MBV or other viruses, the mouse anti-25Pmbv antiserum showed strong immunoreactivity to occlusion bodies of MBV only. It also showed strong reactivity to the 58 kDa putative polyhedrin protein in Western blots. Altogether, the results suggest that the 58 kDa protein is Thai MBV polyhedrin and that a previously reported MBV polyhedrin gene sequence may represent another protein or polyhedrin from a different variety of MBV.  相似文献   

19.
SINPV基因组酶切图谱及多角体基因的序列分析   总被引:6,自引:0,他引:6  
用限制性内切酶EcoRI、XabI、XhoI、BamHI、PstI、SacI、HidnⅢ、SmaI酶解斜纹夜蛾核多角体病毒广州株基因组DNA,分别得到26、26、24、20、13、17、9、1条片段,并算得基因组平均大小为136.0kbp。以AcNPV多角体基因的部分读码框为探针,经Southem杂交将SINPV多角体基因定位于XbaIO片段上。将此片段克隆并序列分析,结果表明SI  相似文献   

20.
The article presents the results of bioassaying 39 samples of TM Biocontrol-1, a viral insecticide, from 10 different lots and various sizes of vacuum-sealed packages that were stored at -10 degrees C for 5-15 yr. This is the first study to present potency data for a registered virus product stored for this length of time. Laboratory bioassays in insects from the same colony from which the TM Biocontrol-1 was produced showed that the stored viral insecticide is still effective, although it lost approximately 30% of its effectiveness during storage. A direct correlation of this loss with the length of time in storage is not apparent. Bioassays also showed that there are significant differences in the susceptibility of Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough), larvae from different geographic regions to OpMNPV (family Baculoviridae, genus Nucleopolyhedrovirus) infection. Package size did not affect the potency of stored TM Biocontrol-1. There were no clear, significant differences in the effectiveness among lots of TM Biocontrol-1 processed by different organizations.  相似文献   

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