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PubMed2000

Human 5-hydroxytryptamine(5A) receptors activate coexpressed G(i) and G(o) proteins in Spodoptera frugiperda 9 cells.

The ability of the human 5-hydroxytryptamine serotonin type 5A (h5-ht(5A)) receptor to couple to G proteins from distinct families was investigated through the simultaneous infection of Spodoptera frugiperda 9 insect cells with recombinant baculoviruses encoding the various proteins. Expression of G proteins was demonstrated in immunoblots. Receptor-G protein coupling was monitored by high-affinity agonist binding and agonist-induced stimulation of [(35)S]guanosine-5'-O-(3-thio) triphosphate binding to membranes. Receptors expressed alone displayed low-affinity agonist binding, and endogenous G proteins were only poorly stimulated on the addition of 5-hydroxytryptamine. When receptors were coexpressed with mammalian G(i)/G(o) proteins (Galpha(i) or Galpha(o) plus Gbeta(1)gamma(2)), the coupled phenotype was achieved: agonists bound with high affinity in a guanosine-5'-(beta, gamma-imido)triphosphate-sensitive manner and stimulated [(35)S]guanosine-5'-O-(3-thio)triphosphate binding to high levels. These effects were not observed on coexpression with G(z)/G(s)/G(q/11/16) or G(12/13). Various ligands were evaluated for their agonistic, antagonistic, or inverse agonistic behavior in both receptor binding and activation assays. Although G(o) displayed different receptor coupling characteristics than G(i) proteins, no clear coupling preference was evident. Coexpression of receptors and Galpha(i) subunits without Gbeta(1)gamma(2) produced increases in both agonist affinity and maximum G protein activation that were smaller than those in the presence of Gbeta(1)gamma(2), suggesting that Gbeta(1)gamma(2) coexpression improves receptor-G protein coupling. Similarly, coexpression of receptors with Gbeta(1)gamma(2) alone resulted in an improved interaction with endogenous G proteins. Our results demonstrate that h5-ht(5A) receptors expressed in Spodoptera frugiperda 9 cells selectively and functionally couple to coexpressed mammalian G(i) and G(o) proteins.

Animals↗
PubMed2004

Influence of the nonsteroidal ecdysone agonist, tebufenozide, on certain biological and physiological parameters of the cotton leaf-worm, Spodoptera littoralis (Boisd.) (Noctuidae: Lepidoptera) in Egypt.

In Egypt, cotton represents the most economical and important field crop. Cotton plant is the target of different pest species from cultivation until harvest. The Egyptian cotton leaf-worm, Spodoptera littoralis (Boisd.) (Noctuidae: Lepidoptera), is an important polyphagous insect pest attacking cotton, several cultivated crops and ornamentals worldwide. The integrated pest management (IPM) programs create the need for novel insecticides having more selective modes of action. So, the no steroidal ecdysteroid mimic, tebufenozide (RH-5992) was studied on some parameters of Spodoptera littoralis. This compound exhibits, in spite of its nonsteroidal structure, a high affinity for the ecdysteroid receptors (EcRs) through a lock-and key principle just like the natural insect molting hormone 20, hydroxyecdysone (20E). The present investigation was performed to throw more light on the following objectives: (1) the toxicity of tebufenozide against the fifth larval instar of a laboratory strain of S. littoralis, (2) the effect of this compound on some biological parameters, i.e. weight of mature larvae, mortality and percentages of larval malformations, (3) the action on some haematological parameters such as blood volume, total haemocyte counts (THCs), absolute haemocyte counts, differential haemocyte counts, and (4) the characterization of haemolymph proteins in treated as well as in the untreated larvae, using the electrophoresis technique on acrylamide gel expressed in the electrophoretic mobility. The obtained results could be summarized as follows: (1) the treated larvae reached their maximum weight after 48 h from treatment with tebufenozide; while the untreated ones reached the maximum weight after 72 h (2) the highest mortality (73%) occurred by applying tebufenozide at the concentration of 18 ppm. In addition, the deduced percentage of larval malformations, indicated that the maximum rate of malformed larvae was attained using the concentration of 36 ppm (3) the blood volume of the 5th instar larvae reached its maximum after 72 h from treatment; while in the untreated ones blood volume increased gradually and reached the maximum rate after 96 h (4) the total haemocyte counts (THCs) decreased in comparison with the control. The maximum value of THCs occurred at 72 h, resembling a lower rate (50%) than that of the untreated ones. (5) The absolute counts reached their maximum rates after 72 h from treatment. It was lower (80.7%) than the untreated larvae. (6) Tebufenozide cause the induction of (10.7 & 14.3 Kda) polypeptide in the haemolymph after 24 h of application. These bands were absent in that time in the untreated larvae (control). Later on, these bands were formed in the control larvae after 72 h of treatment. Induced synthesis of these transcript resulted in precocious molting.

Animals↗
PubMed2005

[Bioactivity of azadirachtin and its field efficiency against Spodoptera litura].

In this paper, the effects of varying concentration azadirachtin on tobacco cutworm Spodoptera litura were investigated in both laboratory and field. The results showed that azadirachtin exhibited a wide range of bioactivities, including anti-feeding, growth inhibition, larval toxicity, and oviposition deterrent. This compound could significantly reduce pupal weight and pupation and eclosion rates. After treated with 12 microl x L(-1) azadirachtin for 5 and 7 days, the third instar larvae only weighted 36.8% and 14.5% of the untreated ones, and their development took approximately 6 days longer, with a 27.79% pupation rate and a 37.23% emergence rate, significantly lower than the control by 85.66% and 82.11%, respectively. Azadirachtin was more efficient for the low instar larva than the old ones. Field experiments confirmed that after 7 days application, azadirachtin could effectively control Spodoptera litura, being more efficient than the chemistry pesticide, 10% Chu-Jin SC.

Animals↗
PubMed1982

Structural reactions to polarized light of microvilli in photoreceptor cells of the moth Spodoptera.

Intact armyworm moths (Spodoptera exempta, Fam. Noctuidae) were illuminated by polarized monochromatic light to induce structural changes in the rhabdomeres of the compound eyes. The degree of distortion of their microvilli depends on the light energy absorbed per time unit. Under polarized light, the number of quanta absorbed varies with the position of the plane of polarization relative to the axis of the microvilli (intrinsic dichroism). Therefore, in Spodoptera, different degrees of deformations could be demonstrated in differently oriented rhabdomeres of both types of ommatidia. Moreover, in rhabdoms of the lobed type with fan-like arranged microvilli, different reactions were regularly seen in differently oriented microvilli of one rhabdomere. This indicates that microvilli may react to light individually.

Animals↗
PubMed1984

Mutagenic effects of aflatoxin B-1 and G-1 on the Egyptian cotton leaf-worm, Spodoptera littoralis (Boisd.).

The aim of this study was to test infertility of the Egyptian cotton leaf-worm, Spodoptera littoralis. Three concentrations, 0.8, 1.6 and 2.0 micrograms/larva of aflatoxin B-1 and G-1 were applied to the final instar of the larval period. Both B-1 and G-1 induced mutagenic effects on spermatogenesis and morphogenesis which consequently reflected in infertility of Spodoptera littoralis. The phenomenon of mutagenicity was more obvious in larvae treated with G-1 rather than in those treated with B-1. The two analogues were also capable of inducing malformations in sperms. These abnormalities were transmitted to and inherited by the progeny.

Aflatoxin B1↗
PubMed1986

Studies on Autographa californica nuclear polyhedrosis virus replication in Spodoptera littoralis cells including virus-induced protein synthesis.

The replication of the Autographa californica nuclear polyhedrosis virus in Spodoptera littoralis cells has been investigated. Various cytopathic changes were detected by light and electron microscopy and progeny enveloped virus particles, some occluded within polyhedra, were later seen in the nucleus of infected cells. Infectious virus was released into the growth medium and increased exponentially from ca. 10 to 24 hours post infection and then slowly increased over the next 4 days. In comparison, virus was released ca. 3.5 hours earlier from Spodoptera frugiperda cells. Total rates of DNA and protein synthesis were drastically reduced during the late stages of virus replication when cell death was occurring. By ca. 18 hours post infection, a clear switch from host to virus induced protein synthesis had occurred and a total of 39 virus-induced polypeptides of M.W. 12 to 120 X 10(3) were detected. These included polyhedrin of M.W. 33 X 10(3), which was particularly prominent during the late stages of virus replication, and a major virus structural protein of M.W. 42 X 10(3).

Animals↗
PubMed1977

The establishment of two cell lines from the insect Spodoptera frugiperda (Lepidoptera; Noctuidae).

The history and characteristics of two cells lines developed from primary explants of pupal tissue from the insect, Spodoptera frugiperda (J.E. Smith), are described. One cell line, IPLB-SF 21, was developed with hemolymph-supplemented medium and has been maintained continuously on the medium. The second cell line, IPLB-SF-1254, was developed with a medium containing a combination of vertebrate sera plus hemolymph and was adapted to hemolyphn-free medium at the 6th passage. The IPLB-SF-21 cell line has a population doubling time of 26 to 30 hr; the doubling time of the IPLB-SF-1254 line is 36 hr. The chromosomal morphology and distribution was typical of other lepidopteran cell lines. Serological studies showed that both cell lines have at least one antigen which also is common is tissue antigens from pupae of Spodoptera frugiperda.

Animals↗
PubMed1985

Infectivity assays for the Autographa californica nuclear polyhedrosis virus using Spodoptera littoralis cells.

Tissue culture ID50 and plaque assays for the Autographa californica nuclear polyhedrosis virus, using the Spodoptera littoralis cell line HPB-SL, were developed. Direct comparison using these assay methods showed that these cells were as susceptible to infection as the more commonly used Spodoptera frugiperda cell line IPLB-SF-21. Both infectious tissue culture supernatants or virus isolated directly from polyhedra could be titrated. It was important to use low cell seeding densities in the assays so that clear centres of infection formed. Dose-response curves indicated that one infectious particle was capable of initiating an infection. Virus could be cloned using either method even though, for the plaque assay, plates had been stained. The tissue culture ID50 assay was performed using 96-well plates and required an incubation period of about 10 days. The plaque assay used a simple nutrient agarose overlay and an incubation period of 5-6 days. Easily countable plaques of 0.3-1.2 mm diameter were detected after staining with iodonitrote-trazolium chloride. The plaques comprised areas of inhibited cell division and round or dead cells. Most plaques contained only some cells with polyhedra and yields averaged about 1/cell. Occasionally plaques or infected wells were found in which no polyhedra could be seen. These infectivity assays are therefore not dependent on polyhedra formation.

Animals↗
PubMed1981

Gossypol as an inducer or inhibitor in Spodoptera littoralis larvae.

Gossypol occurs naturally in the pigment glands in cotton. It has a role in protecting cotton plants from insect pests such as bollworms, yet it was not toxic to the cotton leafworm larvae Spodoptera littoralis up to 2-5% concentration in artificial diet or at 125 micrograms/ larva by topical application. The compound inhibited protease and lipid peroxidase activities in larvae with in vitro I50 values of 1.5 X 10(-3)M, and 4.4 X 10(-4)M respectively. When gossypol was fed to Spodoptera larvae, it stimulated the microsomal N-demethylase in vitro. This inductive effect was time-dependent similar to that of phenobarbital. Gossypol stimulates ATPase at lower concentrations and inhibited it at higher concentrations. The I50 for mitochondrial ATPase was 1.7 X 10(-4)M, while the corresponding values for DDT and fenvalerate were 1.1 X 10(-4)M and 7.0 X 10(-4)M respectively. Gossypol at 1.5% concentration in the diet reduced the larval weight to 50% of the control within two days, and increased the duration of each larval stage. The number of eggs and their hatchability was seriously decreased in larvae treated for three consecutive generations. Such an effect can be attributed to the ability of gossypol to interfere with protein bio-synthesis.

Adenosine Triphosphatases↗
PubMed1998

Naturally occurring deletion mutants are parasitic genotypes in a wild-type nucleopolyhedrovirus population of spodoptera exigua

A wild-type nucleopolyhedrovirus (NPV) isolate from Spodoptera exigua from Florida (Se-US2) is a variant of the SeMNPV type strain since it has a unique DNA profile but is closely related to other known geographical isolates of SeMNPV. It consists of several genotypic variants, of which seven were identified in a Se-US2 virus stock by a modification of the in vivo cloning method developed by Smith and Crook (Virology 166:240-244, 1988). The US2A variant was the most prevalent genotype, and it was designated the prototype Se-US2 variant, while four of the variants (US2B, US2D, US2F, and US2H) were found at low frequency. US2C and US2E were also very abundant, and their diagnostic bands were easily observed in wild-type isolate restriction endonuclease patterns. The analysis of each variant, compared to the prototype US2A, showed that US2B and US2H presented minor differences, while US2D and US2F contained slightly larger insertions or deletions. Variants US2C and US2E contained major deletions of 21.1 and 14 kb, respectively, mapping at the same genomic region (between 14.5 and 30.2 map units [m.u.] and between 12.8 and 23 m.u., respectively). This is the first report of such deletion mutants in a natural baculovirus population. Variants US2A, US2B, US2D, US2F, and US2H were isolated as pure genotypes, but we failed to clone US2C and US2E in vivo. When these two variants appeared without apparent contamination with any other variant, they lost their pathogenicity for Spodoptera exigua larvae. A further biological characterization showed evidence that these two naturally occurring deletion mutants act as parasitic genotypes in the virus population. Bioassay data also demonstrated that pure US2A is significantly more pathogenic against second-instar S. exigua larvae than the wild-type isolate. The need for precise genotypic characterization of a baculovirus prior to its development as a bioinsecticide is discussed.

Journal Article↗
PubMed1990

A novel Bacillus thuringiensis gene encoding a Spodoptera exigua-specific crystal protein.

Only one of the four lepidoptera-specific crystal protein subclasses (CryIC) Bacillus thuringiensis was previously shown to be highly toxic against several Spodoptera species. By using a cryIC-derived nucleotide probe, DNA from 25 different strains of B. thuringiensis was screened for the presence of homologous sequences. A putative crystal protein gene, considerably different from the cryIC gene subclass, was identified in the DNA of strain 4F1 (serotype kenyae) and cloned in Escherichia coli. Its nucleotide sequence was determined and appeared to contain several features typical for a crystal protein gene. Furthermore, the region coding for the N-terminal part of the putative toxic fragment showed extensive homology to subclass cryIA sequences derived from gene BtII, whereas the region coding for the C-terminal part appeared to be highly homologous to the cryIC gene BtVI. With an anti-crystal protein antiserum, a polypeptide of the expected size could be demonstrated in Western immunoblots, onto which a lysate of E. coli cells harboring the putative gene, now designated as BtXI, had been transferred. Cells expressing the gene appeared to be equally toxic against larvae of Spodoptera exigua as recombinant cells expressing the BtVI (cryIC)-encoded crystal protein. However, no toxicity against larvae of Heliothis virescens, Mamestra brassicae, or Pieris brassicae could be demonstrated. The nucleotide sequence analysis and the toxicity studies showed that this novel crystal protein gene falls into a new cryl gene subclass. We propose that this subclass be referred to as cryIE.

Amino Acid Sequence↗
PubMed2026

Functional analysis of down-regulated CYP6AE gene clusters involved in the insecticidal mechanism of lycorine against Spodoptera litura.

BACKGROUND: Plants have evolved abundant defensive secondary metabolites to resist insect herbivores. Lycorine is an alkaloid with insecticidal activity from Amaryllidaceae plants, which the destructive pest Spodoptera litura naturally avoids. Cytochrome P450 enzymes are central to xenobiotic detoxification in insects, but the mechanism by which lycorine acts against S. litura remains unknown. This study aimed to reveal the toxic mechanism of lycorine focusing on P450-mediated detoxification. RESULTS: Lycorine exhibited substantial toxicity to first-instar S. litura larvae (LD50 = 0.55 μg larva-1). Subsequently, when fifth-instar larvae were exposed to a sublethal dose (LD30) of lycorine, Lyc disrupted metabolic pathways, damaged Malpighian tubules, and induced oxidative stress. Furthermore, lycorine strongly repressed a CYP6AE gene cluster (CYP6AE47, CYP6AE50, CYP6AE70, CYP6AE138 and CYP6AE139) and decreased total P450 activity to 45% in the Malpighian tubules. RNAi co-silencing of these cluster genes increased larval mortality (+30%) under lycorine treatment. Finally, molecular docking and microscale thermophoresis analyses further confirmed direct binding between Lyc and this CYP6AE gene cluster, with the strongest affinity observed for CYP6AE47 (Kd = 518.5 nM). A key residue, ARG170, may be vital for the interaction between Lyc and CYP6AE47. CONCLUSIONS: These results demonstrate that the insecticidal mechanism of Lyc involves suppressing the expression and function of a CYP6AE gene cluster, thereby impairing detoxification capacity, which leads to Lyc accumulation and larval mortality. Elucidation of the detoxification system-targeted mechanism for this plant-derived compound provides a foundation for developing novel, sustainable pest management strategies against S. litura and potentially other noctuid pests. © 2026 Society of Chemical Industry.

Animals↗
PubMed2026

Transcriptomic insights into thermal stress reveal physiological trade-off between thermal stress adaptation and reproductive investment in Spodoptera litura.

Spodoptera litura, a highly polyphagous lepidopteran pest, poses a major threat to agricultural productivity due to its remarkable adaptability to diverse environmental conditions. Although heat stress is known to trigger transcriptional reprogramming in insects, the molecular mechanisms underlying thermal stress responses in S. litura remain poorly understood. In the present study, fourth-instar larvae were exposed to acute heat stress (44 °C) and compared with control conditions (27 ± 1 °C) to investigate heat-induced transcriptional alterations affecting physiology and reproduction. High-quality RNA-Seq data achieved more than 80% mapping efficiency, with a total of 15,782 transcripts were identified. Transcriptome analysis of S. litura larvae showed 323 differentially expressed genes (DEGs), of which 262 genes were significantly upregulated and 61 were downregulated in heat-stressed larvae compared to the control group. The DEGs were associated with stress response, reproduction, signalling, proteostasis, detoxification, oxidative stress, metabolism, development, and chromatin regulation. Heat shock proteins genes, including HSP70, HSP90, and HSP27, together with co-chaperones such as TRET-1, STIP1, and Starvin, were strongly upregulated, indicating enhanced cellular protection against protein damage and oxidative stress under heat stress. Conversely, key reproductive and cell cycle-related genes, including BARR, CAPD2, FEO, CDK2 and MORULA, were significantly downregulated, suggesting reproductive impairment and developmental arrest. RT-qPCR validation corroborated the RNA-Seq findings, demonstrating a heat-induced physiological trade-off that prioritizes survival over reproduction. Consistent with these molecular responses, heat-stressed insects exhibited marked reproductive impairment, including significant reductions in gonadosomatic index, eupyrene sperm bundle count, mating frequency, mating success, female calling behaviour, copulation duration, fecundity, and egg fertility. Collectively, these findings provide comprehensive insights into the molecular basis of thermal adaptation in S. litura and demonstrate that acute heat stress compromises reproductive fitness while activating conserved stress-response pathways that promote short-term survival.

Animals↗
PubMed1998

Cloning and expression of apolipophorin-III from the common cutworm, Spodoptera litura.

We have cloned apolipophorin-III (apoLp-III) cDNA from adult fat body of Spodoptera litura. The sequence encodes a 188 amino acid polypeptide including a 22 amino acid leader peptide. The circular dichroism spectrum from the purified apoLp-III indicated a considerable content of alpha-helix. Sequence alignment showed that S. litura apoLp-III has a relatively high degree of sequence identity with the apoLps-III of lepidopteran, Manduca sexta (72%), Galleria mellonella (67%), Bombyx mori (60%). These alignments with four lepidopteran apoLps-III showed highly identical residues and conservative replacements at a degree of 86%. Levels of mRNA from last instar larval fat body and adult fat body were compared through Northern blot analysis using 32-P-labeled 704 bp apoLp-III cDNA probe. A 850 bp mRNA was detected in both stages and mRNA level of day 1 adult fat body was much higher than that of last instar larval fat body. The tissue-distribution of apoLp-III mRNA in adult ovary and testis was also examined and we confirmed the presence of apoLp-III mRNA in ovary and testis although apoLp-III was expressed in these tissues at very low levels compared with the adult fat body.

Amino Acid Sequence↗
PubMed2000

Hematopoiesis in larval Pseudoplusia includens and Spodoptera frugiperda.

Maintenance of circulating hemocytes in larval Lepidoptera has been attributed to both mitosis of hemocytes already in circulation and the release of hemocytes from hematopoietic organs. In this study, we compared hematopoiesis in the noctuids Pseudoplusia includens and Spodoptera frugiperda. For both species, hemocyte densities per microl of blood increased with instar. Differential hemocyte counts indicated that plasmatocytes were the most abundant hemocyte type during early instars but granular cells were the most abundant hemocyte type in the last instar. Hematopoietic organs were located in the meso- and metathorax of S. Frugiperda and P. Includens. These organs contained large numbers of hemocytes in S. Frugiperda, but contained few hemocytes in P. Includens. The majority of the hemocytes recovered from hematopoietic organs were identified as plasmatocytes. Using hemocyte type-specific markers and bromodeoxyuridine (BrdU) incorporation experiments, we determined that all hemocyte types with the exception of oenocytoids synthesize DNA. BrdU labeling indices for both species also fluctuated with the molting cycle. Ligation experiments suggested that hematopoietic organs are an important source of circulating plasmatocytes in S. Frugiperda but not in P. Includens. Injection of heat killed bacteria into larvae induced higher levels of BrdU labeling than injection of sterile saline, suggesting that infection and wounding induce different levels of hemocyte proliferation. Arch.

Animals↗
PubMed2002

Purification and characterization of biliverdin-binding vitellogenin from the hemolymph of the common cutworm, Spodoptera litura.

Biliverdin-binding vitellogenin (Vg) was purified from adult female hemolymph of the common cutworm, Spodoptera litura, by using gel filtration and ion exchange chromatographies. The molecular mass of the protein was 490 kDa and it was composed of two 188-kDa subunits. Three internal amino acid sequences obtained by digestion of the protein with lysylendopeptidase showed high similarity to those of Bombyx mori Vg, supporting the purified blue protein to be vitellogenin. latroscan analyses demonstrated the presence of biliverdin in Vg that occupied 2.4% of total lipid components. Among the lipids of Vg (9.5 micrograms total lipids per 100 micrograms protein), diacylglycerol was the most predominant, followed by phospholipid, hydrocarbons, and then triacylglycerol, while in biliverdin-binding proteins (BPs) purified from larval hemolymph (3.1 micrograms total lipids per 100 micrograms protein), phospholipid was the most abundant lipid followed by diacylglycerol; hydrocarbons and triacylglycerol were minor components. Vg was first detected in the hemolymph of female pupae one day before eclosion, but injection of 5 micrograms of methoprene into a 3-day-old pupa induced Vg in the hemolymph 4 days earlier than in the control. Methoprene also induced a faster decline in BP-A and BP-B titers in the hemolymph with a corresponding increase of the Vg titer. These results suggest that juvenile hormone (JH) induces not only vitellogenesis but also the uptake of these proteins by stimulating the metamorphosis of fat body during the pupal stage.

Amino Acid Sequence↗
PubMed2003

Xenorhabdus nematophilus inhibits p-bromophenacyl bromide (BPB)-sensitive PLA2 of Spodoptera exigua.

Xenorhabdus nematophilus is a Gram-negative symbiotic bacterium of the entomopathogenic nematode, Steinernema carpocapsae. The bacteria delivered into the insect hemocoel by the nematodes cause immunodepression of the target insects to protect host nematodes and themselves from the cellular immune reaction. Previous reports suggest that the immunodepression is caused by inhibition of the eicosanoid pathway that is known to be critically important to mediate cellular immunity. This study focused on the inhibitory effect of X. nematophilus on PLA2 activity of Spodoptera exigua. The PLA2 activity was functionally associated with the activation cascade of prophenoloxidase (pPO). Dexamethasone (DEX), a specific PLA2 inhibitor, inhibited pPO activation completely at the higher doses of approximately 2.4 muM in vitro condition. The inhibitory effect of DEX was reversed by the addition of arachidonic acid, the catalytic product of PLA2. By means of this in vitro PLA2 inhibitor assay system, two different PLA2 inhibitors were used to compare their inhibitory effects on the hemolymph PLA2 of S. exigua. p-Bromophenacyl bromide (BPB), a specific inhibitor of secretory PLA2 (sPLA2), significantly inhibited pPO activation, but methylarachidonyl fluorophosphates (MAFP), a specific inhibitor of cytosolic PLA2 (cPLA2), did not show any inhibitory effect. BPB also inhibited pPO activation of the plasma, though much higher PO activation and its inhibition by BPB was found in the hemocytes. Growth medium of X. nematophilus at the stationary phase had a PLA2 inhibitory effect. Via the in vitro PLA2 inhibitor assay, it was shown that the ethyl ether extract of the medium contained significant PLA2 inhibitor activity. These results indicate that X. nematophilus produces and secretes PLA2 inhibitor, which acts on BPB-susceptible PLA2 of S. exigua.

Acetophenones↗
PubMed2004

Expression and localization of the Spodoptera frugiperda allatotropin (Spofr-AT) and allatostatin (Spofr-AS) genes.

Manduca sexta allatotropin and allatostatin were the first corpora allata (CA) regulating neuropeptides identified from Lepidoptera. Recently, we cloned the allatotropin (Spofr-AT) and the allatostatin (Spofr-AS) genes from the fall armyworm Spodoptera frugiperda. Using one-step RT-PCR for semi-quantification of the gene expression, we now demonstrate that three mRNA isoforms of the Spofr-AT gene and the Spofr-AS gene are expressed in brain, digestive tract, and reproductive organs of larvae, pupae, and adults in a time- and tissue-specific manner. Expression rates in the brain and in various parts of the digestive tract prove the dual role of the peptides as brain/gut (neuro)peptides. The functional meaning of ovarian and testes expression of the genes is not yet clear, although myoregulatory properties of the peptides are probable. The tissue-specific localization of the prohormone expression, as demonstrated by whole mount in situ hybridization, confirms the overall distribution of the prohormones as shown by RT-PCR and supports the pleiotropic functions of the peptides.

Animals↗