Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Spodoptera”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Coinfection of Spodoptera exigua and Spodoptera frugiperda cell lines with the nuclear polyhedrosis viruses of Autographa californica and Spodoptera exigua.

The Autographa californica multinucleocapsid nuclear polyhedrosis virus (AcMNPV) has a broad host range among Lepidoptera. In contrast, the Spodoptera exigua MNPV (SeMNPV) can replicate efficiently only in S. exigua larvae or S. exigua-derived cell lines. In this study, we examined the coinfection of S. exigua Se301 and Spodoptera frugiperda IPLB-SF21AEII (Sf21) cell lines with SeMNPV and AcMNPV recombinant (Ac360-501beta-gal) which was constructed for expression of beta-galactosidase under control of the polyhedrin promoter. Coinfection led to the restriction as the level of late gene expression, nonoccluded virus production, and DNA replication of Ac360-501beta-gal in both Se301 and Sf21 cell lines. In contrast, Ac360-501beta-gal supported the SeMNPV replication in Sf21 cells. Occurrence of recombinants, between Ac360-501beta-gal and SeMNPV, with expanded host range was not observed in coinfected Sf21 cells. This suggests that Ac360-501beta-gal supports the SeMNPV replication through trans-activation.

Animals↗

Toxicity, binding, and permeability analyses of four Bacillus thuringiensis Cry1 delta-endotoxins using brush border membrane vesicles of Spodoptera exigua and Spodoptera frugiperda.

The binding and pore formation properties of four Bacillus thuringiensis Cry1 toxins were analyzed by using brush border membrane vesicles from Spodoptera exigua and Spodoptera frugiperda, and the results were compared to the results of toxicity bioassays. Cry1Fa was highly toxic and Cry1Ac was nontoxic to S. exigua and S. frugiperda larvae, while Cry1Ca was highly toxic to S. exigua and weakly toxic to S. frugiperda. In contrast, Cry1Bb was active against S. frugiperda but only marginally active against S. exigua. Bioassays performed with iodinated Cry1Bb, Cry1Fa, and Cry1Ca showed that the effects of iodination on toxin activity were different. The toxicities of I-labeled Cry1Bb and Cry1Fa against Spodoptera species were significantly less than the toxicities of the unlabeled toxins, while Cry1Ca retained its insecticidal activity when it was labeled with 125I. Binding assays showed that iodination prevented Cry1Fa from binding to Spodoptera brush border membrane vesicles. 125I-labeled Cry1Ac, Cry1Bb, and Cry1Ca bound with high-affinities to brush border membrane vesicles from S. exigua and S. frugiperda. Competition binding experiments performed with heterologous toxins revealed two major binding sites. Cry1Ac and Cry1Fa have a common binding site, and Cry1Bb, Cry1C, and Cry1Fa have a second common binding site. No obvious relationship between dissociation of bound toxins from brush border membrane vesicles and toxicity was detected. Cry1 toxins were also tested for the ability to alter the permeability of membrane vesicles, as measured by a light scattering assay. Cry1 proteins toxic to Spodoptera larvae permeabilized brush border membrane vesicles, but the extent of permeabilization did not necessarily correlate with in vivo toxicity.

Journal Article↗

Identification of insertion and deletion genes in Autographa californica nucleopolyhedrovirus variants isolated from Galleria mellonella, Spodoptera exigua, Spodoptera litura and Xestia c-nigrum.

The genomic DNA of four Autographa californica multinucleocapsid nucleopolyhedrovirus (AcMNPV) variants isolated from Galleria mellonella, Spodoptera exigua, Spodoptera litura and Xestia c-nigrum was analyzed in comparison with the AcMNPV E2 strain. Restriction endonuclease analysis revealed a deletion and an insertion in collinear regions of the four variants. Polymerase chain reaction analysis indicated that, in the four variants, the deletion occurred in the region corresponding to AcMNPV C6 ORF86 (pnk/pnl). Also the insertion, with a length of approximately 1.1 kb, was commonly identified in the fragments corresponding to the PstI-J fragment (18.5 m.u.-21.2 m.u.) of AcMNPV E2. Sequencing analysis of the variant from S. litura showed that the insertion contains an additional open reading frame encoding 322 amino acids between homologues of AcMNPV ORF30 and ORF31 (the superoxide dismutase gene). This ORF has 82.8% amino acid identity to Bombyx mori NPV T3 ORF 22 (bro-a, one of the baculovirus repeated ORFs) and thus, it was named Splt-bro-a. Southern blot hybridization study indicated that the other three variants also contain Splt-bro-a homologue. In addition, the labeled Splt-bro-a gene weakly hybridized to the PstI-D fragment (99.0 m.u.-8.0 m.u.) of AcMNPV E2. This fragment contains AcMNPV ORF2, a member of bro family. The signal was also observed on the corresponding fragment of the four variants. This result suggested that two bro genes are present in the four variants, although AcMNPV E2 and C6 are known to contain a single bro gene.

Amino Acid Sequence↗

A new ascovirus from Spodoptera exigua and its relatedness to the isolate from Spodoptera frugiperda.

A new ascovirus was isolated from Spodoptera exigua in Indonesia and was tentatively assigned as a new species, Spodoptera exigua ascovirus 5a (SeAV-5a) according to the present ICTV ascovirus naming scheme based on DNA restriction fragment length polymorphism (RFLP), hybridization, formation of occlusion body, tissue tropism and host spectrum. SeAV-5a replicated primarily in the fat body of susceptible hosts. SeAV-5a could be transmitted to S. frugiperda, Pseudoplusia includens and Trichoplusia ni, but not to Heliothis virescens. Infection with SeAV-5a arrested growth of the hosts, but prolonged their survival, which continued up to 33 days. Clusters of virions were seen inside the characteristic vesicles. Occasionally, virions were contained within vacuoles (one to five per vacuole) and some virions were embedded in occlusion bodies. The size of the SeAV-5a virion was 347x134 nm; however, aberrant long secondary viral products were also seen. The presence of occlusion body and Southern hybridization and Western immunoblot analyses suggest that SeAV-5a is more closely related to S. frugiperda ascovirus 1a (SfAV-1a) than to Trichoplusia ni ascovirus 2 (TnAV-2). Certain regions of the 182 kb genome of SeAV-5a showed hybridization to that of SfAV-1a. Two fragments in each of the SfAV-1a ECO:RI and HINdIII digests hybridized to the SeAV-5a genomic DNA probe. Five to eight HINdIII and ECORI fragments in SeAV-5a DNA hybridized to the SfAV-1a genomic probe.

Animals↗

Plaque assay for Spodoptera exigua and Autographa californica nuclear polyhedrosis viruses in a newly established cell line of the beet armyworm, Spodoptera exigua.

The nuclear polyhedrosis viruses of Spodoptera exigua (SeNPV) and Autographa californica (AcNPV) produced plaques in a newly established cell line of the beet armyworm, Spodoptera exigua. Plaques were composed of infected cells containing many polyhedra and were visible without any staining procedure. Dose-response assays showed a direct correlation between the number of plaques and the inoculum size. Growth kinetic studies of the two viruses, using the developed plaque assay system, revealed that the release of extracellular viruses began 6 hrs post infection (p.i.) and the titer reached a plateau 48 hrs p.i. The sensitivity of this plaque assay system was 100 times greater for the heterologous AcNPV than for the homologous SeNPV.

Animals↗

Persistent baculovirus infections: Spodoptera frugiperda NPV and Autographa californica NPV in Spodoptera frugiperda cells.

Establishment of a persistent infection of Spodoptera frugiperda nuclear polyhedrosis virus (NPV) in Spodoptera frugiperda (S.f.) cells occurred in three phases: the first phase was characterised by high levels of cell infection and death, the second phase by decreasing cell infection levels leading to the final phase where less than one per cent of the cells were infected during any subculture. The virus persisted at this level of infection provided the cells were maintained by regular subculturing and incubated at the optimum growth temperature of 27 degrees C. Because of the low proportion of cells infected, cultures of virus-free cells could be selected ('cured') by dilution of the persistent infection without the use of viral antiserum. Unlike the parent S.f. cells, cultures of cured cells were partially resistant to infection with S. frugiperda NPV or infection with an unrelated baculovirus Autographa californica NPV. A. californica NPV, which is cytolytic for the parent S.f. cell line, established a persistent infection in the cured cells. The establishment pattern was similar to that previously found for S. frugiperda NPV and only one to five per cent of the cells were infected at equilibrium. Cured cells from the A. californica NPV persistent infection were highly resistant to infection with both S. frugiperda NPV and A. californica NPV. All attempts to find a viral interference phenomenon to explain the resistance of the cured cells were unsuccessful. All cell types adsorbed virus equally well. Slower growth of S.f. cells cured from the persistent A. californica NPV infection is the only difference so far observed between any of the S.f. cell types.

Animals↗

Seasonal abundance of two armyworm species, Spodoptera exitgua (Hübner) and Spodoptera litura (F.) in the Philippines.

The two armyworm species Spodoptera exigua (Hübner) and S. litura (F.) are Important pests on several agricultural crops in the tropics. Knowledge about species abundance is important for the development of integrated pest management strategies. During 1998 and 1999 population densities were recorded weekly using pheromone traps at San Leonardo and Munoz (Province Nueva Ecija, 150 km north of Metro Manila) on the Philippine island Luzon. Furthermore, meteorological conditions and natural enemies were observed. Both armyworm species were present year-round at both observation sites. No differences in numbers of male insects trapped in pheromone traps between seasons were found for S. litura. Contrary, numbers of male S. exigua trapped during rainy season was significant higher than during dry season. Rainfall explained between 30 and 40% of trapped moths and has to be considered when monitoring population density with pheromone traps. Parasitism rates were below 5% in both years and for both species and can not explain the high variation observed in population densities.

Animals↗

The effects of inhibitors of nucleic acid and protein synthesis on the replication of Spodoptera frugiperda nuclear polyhedrosis virus in cultured Spodoptera frugiperda cells.

The effects of inhibitors of nucleic acid and protein synthesis on the replication of Spodoptera frugiperda nuclear polyhedrosis virus have been determined. Two inhibitors of protein synthesis-cycloheximide and puromycin-were irreversible inhibitors of virus multiplication. Three inhibitors of nucleic acid synthesis-actinomycin D, cytosine arabinoside and camptothecin- prevented virus multiplication; only camptothecin was reversible. Rifampicin had no effect on virus multiplication.

Camptothecin↗

Antibacterial properties and partial cDNA sequences of cecropin-like antibacterial peptides from the common cutworm, Spodoptera litura.

The antibacterial properties and cDNA sequences of two types of antibacterial peptides from the haemolymph of immunized common cutworm, Spodoptera litura larvae, were determined. Since the primary structures of peptides deduced from cDNA sequences showed significant homologies to cecropins A and B, they were named as Spodoptera cecropins A and B. Spodoptera cecropins were broadly effective against Gram-positive and negative bacteria. They also retained antibacterial activities in all conditions tested (at pH 5.6-8.0 and in the presence of 50-150 mM NaCl) that was adapted to confirm the antibacterial properties of Spodoptera cecropins. These results indicate that the change of pH and the increase of salt concentration in the media do not influence the activities of Spodoptera cecropins. For the reverse transcription (RT)-polymerase chain reaction (PCR) to obtain the complete primary sequence, the primer designed according to the conserved region of the cecropin leader sequences was used, which was determined by the comparison of the cDNA sequences of known cecropins. The results from RT-PCR presented that the partial cDNAs of Spodoptera cecropins A and B encode 57 and 58 amino acids, including the sequences of mature peptides, respectively. In addition, Northern blot analysis with (32)P-labeled PCR product coding for Spodoptera cecropin A revealed that Spodoptera cecropin genes are expressed in immunized fat body, but not in normal fat body.

Amino Acid Sequence↗

UDP-glycosyltransferases act as key determinants of host plant range in generalist and specialist Spodoptera species.

Phytophagous insects have evolved sophisticated detoxification systems to overcome the antiherbivore chemical defenses produced by many plants. However, how these biotransformation systems differ in generalist and specialist insect species and their role in determining insect host plant range remains an open question. Here, we show that UDP-glucosyltransferases (UGTs) play a key role in determining the host range of insect species within the Spodoptera genus. Comparative genomic analyses of Spodoptera species that differ in host plant breadth identified a relatively conserved number of UGT genes in generalist species but high levels of UGT gene pseudogenization in the specialist Spodoptera picta. CRISPR-Cas9 knockouts of the three main UGT gene clusters of Spodoptera frugiperda revealed that UGT33 genes play an important role in allowing this species to utilize the poaceous plants maize, wheat, and rice, while UGT40 genes facilitate utilization of cotton. Further functional analyses in vivo and in vitro identified the UGT SfUGT33F32 as the key mechanism that allows generalist S. frugiperda to detoxify the benzoxazinoid DIMBOA (2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one), a potent insecticidal phytotoxin produced by poaceous plants. However, while this detoxification capacity is conserved in several generalist Spodoptera species, Spodoptera picta, which specializes on Crinum plants, is unable to detoxify DIMBOA due to a nonfunctionalizing mutation in SpUGT33F34. Collectively, these findings provide insight into the role of insect UGTs in host plant adaptation, the mechanistic basis of evolutionary transitions between generalism and specialism and offer molecular targets for controlling a group of notorious insect pests.

Animals↗

Cytolytic activity of Bacillus thuringiensis CryIC and CryIAc toxins to Spodoptera sp. midgut epithelial cells in vitro.

A sensitive lactate dehydrogenase (LDH) assay was modified to determine the cytolytic activity of Bacillus thuringiensis CryIC and CryIAc delta endotoxins to viable collagenase-dissociated midgut epithelial cells (MEC) from larvae of Spodoptera frugiperda and Spodoptera exigua. The MEC preparations from these Spodoptera sp. consisted predominantly of columnar cells (65-75%) and goblet cells (25-35%). Time course microscopy experiments indicated that only the columnar cells became swollen during CryIC toxin incubation. Also, comparative cytotoxicity studies were run with cell lines of nonmidgut origin established from S. frugiperda (SF21AE) and S. exigua (SEUCR1A). Optimum conditions for the cytotoxicity assay were similar for MEC and cell lines of both species, and were met in an assay in which 0.1-ml cell concentrations (8.5 +/- 0.5 x 10(4) cells) were incubated with toxin dilutions (0.01-20 micrograms) for 1 h at 24 degrees C at a final pH of 7.8. The Spodoptera sp. MEC were twofold more sensitive to CryIC (68% lysis) than CryIAc (32% lysis) at optimum toxin levels (2.5-5 micrograms). Also, the SEUCR1A cells were more sensitive (2.3-fold) to CryIC (70% lysis) than CryIAc (30% lysis) at optimum toxin levels of 5-10 micrograms. The SF21AE cells, however, were twofold less sensitive to CryIC (30% lysis) than SEUCR1A cells and response to CryIAc and CryIC was similar. Immunoblot analysis of either Spodoptera sp. MEC or brush border membrane vesicles (BBMV) identified seven CryIC binding proteins with molecular mass of 137, 120, 115, 68, 65, 63, and 45 kDa. Occasionally, a 148-kDa protein band was observed. The CryIAc toxin bound to two proteins on MEC and BBMV with molecular mass of 137 and 120 kDa.

Animals↗

Virus entry or the primary infection cycle are not the principal determinants of host specificity of Spodoptera spp. nucleopolyhedroviruses.

The multicapsid nucleopolyhedroviruses (NPVs) of Spodoptera exigua (SeMNPV), Spodoptera frugiperda (SfMNPV), and Spodoptera littoralis (SpliNPV) are genetically similar (78 % similarity) but differ in their degree of host specificity. Infection by each of the three NPVs in these three Spodoptera host species was determined by oral inoculation of larvae with occlusion bodies (OBs) or intrahaemocoelic injection with occlusion derived virions (ODVs). RT-PCR analysis of total RNA from inoculated insects, targeted at immediate early (ie-0), early (egt, DNA polymerase), late (chitinase) and very late genes (polyhedrin), indicated that each of the NPVs initiated an infection in all three host species tested. SpliMNPV produced a fatal NPV disease in both heterologous hosts, S. frugiperda and S. exigua, by oral inoculation or injection. SfMNPV was lethal to heterologous hosts, S. exigua and S. littoralis, but infected larvae did not melt and disintegrate, and progeny OBs were not observed. SeMNPV was able to replicate in heterologous hosts and all genes required for replication were present in the genome, as the virus primary infection cycle was observed. However, gene expression was significantly lower in heterologous hosts. SeMNPV pathogenesis in S. frugiperda and S. littoralis was blocked at the haemocoel transmission stage and very nearly cleared. SeMNPV mixtures with SpliMNPV or SfMNPV did not extend the host range of SeMNPV; in all cases, only the homologous virus was observed to proliferate. It is concluded that entry and the primary virus infection cycle are not the only, or the major determinants, for SeMNPV infection of heterologous Spodoptera species.

Animals↗

Replication of Spodoptera exigua nucleopolyhedrovirus in permissive and non-permissive lepidopteran cell lines.

The Spodoptera exigua multinucleocapsid nucleopolyhedrovirus (SeMNPV) was inoculated to eight lepidopteran cell lines derived from Spodoptera exigua (Se301), Spodoptera frugiperda (SF21AEII), Spodoptera littoralis (CLS-79), Spodoptera litura (SpLi-221), Pseudaletia separata (LeSe-11), Trichoplusia ni (hi-5), Plutella xylostella (PXL/C) and Bombyx mori (BmN4). The productive infection of SeMNPV was observed only in Se301 cells. However, a dot-blot hybridization analysis revealed that SeMNPV DNA replicated in five non-permissive cell lines: SF21AEII, CLS-79, SpLi-221, hi-5 and BmN4. In addition, the virus-infected hi-5 and BmN4 cells displayed morphological changes. In contrast, CLS-79 cells inoculated with SeMNPV showed membrane blebbing at 20 hrs post inoculation (p.i.) and fragmentation of genomic DNA. All that indicated that the infected CLS-79 cells underwent apoptosis. These findings indicate that the SeMNPV replication was restricted at various points in dependence upon each cell line.

Animals↗

Immunologically unrelated Heliothis sp. and Spodoptera sp. midgut membrane-proteins bind Bacillus thuringiensis CryIA(b) delta-endotoxin.

The Bacillus thuringiensis toxins, CryIA(a), CryIA(b), CryIA(c) and CryIC were used in a ligand-blot assay to detect specific toxin-binding proteins in the brush-border membranes of Heliothis virescens, Helicoverpa zea, Spodoptera littoralis, Spodoptera exigua and Spodoptera litura. While CryIA(a) and CryIA(b) always recognize the same protein(s) in a given species, CryIA(c) and CryIC were found to bind to other proteins. Polyclonal antibodies directed against the CryIA(b) binding protein of H. virescens and polyclonal anti-idiotype antibodies recognizing some determinants of the CryIA(b)-binding protein involved in the interaction with the toxin, were used to analyse immunological relationships among the toxin-binding proteins. The results showed that the 170-kDa toxin-binding proteins from the H. virescens and H. zea are immunologically related. However, the toxin-binding proteins from the Spodoptera species did not cross-react with either type of antibodies. Therefore, we conclude that the CryIA(b) toxin has different binding determinants on the toxin molecules itself which can interact with specific binding sites on the toxin-binding proteins from Heliothis sp. and Spodoptera sp.

Animals↗

Nucleotide sequence and molecular characterization of the structural glycoprotein gp41 gene homologue of Spodoptera litura nucleopolyhedrosis virus (spltNPV-I).

The structural glycoprotein gene gp41 homologue of Spodoptera litura nucleopolyhedrosis virus (SpltNPV-I *) was identified in the 4.0 kb EcoRI-L fragment of the viral genome. The nucleotide sequence of 2063 bp of this fragment revealed an open reading frame of 1014 nucleotides to encode a polypeptide of 337 amino acids. Analysis of nucleotide and deduced amino acid sequences of the putative ORF indicated its identity with gp41 protein of other baculoviruses sharing maximum homology with that of Spodoptera frugiperda nucleopolyhedrosis virus (SfNPV). The coding sequence was preceded by an AT-rich region containing the consensus baculoviral late promoter motif RTAAG. The putative SpltNPV gp41 ORF was abundantly expressed as a 37 kDa apoprotein in E. coli and as a 50 kDa glycoprotein in Sf9 cells. The recombinant protein expressed in insect cells was glycosylated (20%) and has GlcNAc as the terminal sugar. The gene is conserved among baculoviruses and places SpltNPV-I close to Spodoptera frugiperda and Spodoptera exigua NPVs in phylogenetic tree.

Amino Acid Sequence↗

A synthetic cryIC gene, encoding a Bacillus thuringiensis delta-endotoxin, confers Spodoptera resistance in alfalfa and tobacco.

Spodoptera species, representing widespread polyphagous insect pests, are resistant to Bacillus thuringiensis delta-endotoxins used thus far as insecticides in transgenic plants. Here we describe the chemical synthesis of a cryIC gene by a novel template directed ligation-PCR method. This simple and economical method to construct large synthetic genes can be used when routine resynthesis of genes is required. Chemically phosphorylated adjacent oligonucleotides of the gene to be synthesized are assembled and ligated on a single-stranded, partially homologous template derived from a wild-type gene (cryIC in our case) by a thermostable pfu DNA ligase using repeated cycles of melting, annealing, and ligation. The resulting synthetic DNA strands are selectively amplified by PCR with short specific flanking primers that are complementary only to the new synthetic DNA. Optimized expression of the synthetic cryIC gene in alfalfa and tobacco results in the production of 0.01-0.2% of total soluble proteins as CryIC toxin and provides protection against the Egyptian cotton leafworm (Spodoptera littoralis) and the beet armyworm (Spodoptera exigua). To facilitate selection and breeding of Spodoptera-resistant plants, the cryIC gene was linked to a pat gene, conferring resistance to the herbicide BASTA.

Amino Acid Sequence↗

A noda-like virus isolated from the sweetpotato pest spodoptera eridania (Cramer) (Lep.; noctuidae)

A small isometric virus has been isolated from larvae of the sweetpotato pest Spodoptera eridania (Cramer) collected near Pariacoto, Ancash province, Peru. It is designated the Pariacoto virus (PaV). In addition to its high pathogenicity on its natural host Spodoptera eridania, PaV was found to replicate in Spodoptera ochrea (Hampson) larvae but not in Spodoptera frugiperda (Smith) larvae. The size of the viral particle was estimated to be about 30 nm in diameter. Polyacrylamide gel electrophoresis showed a protein of approximately 40.5 kDa. After agarose gel electrophoresis, the viral genome appeared to be bipartite RNA. Gel immunodiffusion tests showed no serological relationship between PaV and Nodamura virus, the type species for insect nodaviruses. Electron microscopy confirmed that viral replication occurs in the cytoplasm. These properties are similar to those of other members of family Nodaviridae, to which the virus is currently assigned. Copyright 1999 Academic Press.

Journal Article↗