Cry3Aa Toxin Is Not Suitable to Control Lepidopteran Pest (Boisd.).

The toxicity of the (Bt) toxin Cry3Aa-originally used against the main potato pest, the Colorado potato beetle, -was verified on this species and then evaluated against the Egyptian armyworm, , which is a pest of several economically important plants. Larvae of were fed a semi-artificial diet supplemented either with a recombinant or with a natural Bt toxin Cry3Aa and with the genetically engineered (GE) potato of variety Superior NewLeaf (SNL) expressing Cry3Aa. Cry3Aa concentration in the diet and the content in the leaves were verified via ELISA (enzyme-linked immunosorbent assay) and HPLC (high-performance liquid chromatography) during and at the end of the experiments.

The Exact Timing of Microinjection of Parthenogenetic Silkworm Embryos Is Crucial for Their Successful Transgenesis.

The use of parthenogenetic silkworm () strains, which eliminate the problem of recombination, is a useful tool for maintaining transgenic clonal lines. The generation of genetically identical individuals is becoming an important tool in genetic engineering, allowing replication of an existing advantageous trait combination without the mixing that occurs during sexual reproduction. Thus, an animal with a particular genetic modification, such as the ability to produce transgenic proteins, can reproduce more rapidly than by natural mating.

Mutation in Bombyx mori fibrohexamerin (P25) gene causes reorganization of rough endoplasmic reticulum in posterior silk gland cells and alters morphology of fibroin secretory globules in the silk gland lumen.

Larvae of many lepidopteran species produce a mixture of secretory proteins, known as silk, for building protective shelters and cocoons. Silk consists of a water-insoluble silk filament core produced in the posterior silk gland (PSG) and a sticky hydrophilic coating produced by the middle silk gland (MSG). In Bombyx mori, the fiber core comprises three proteins: heavy chain fibroin (Fib-H), light chain fibroin (Fib-L) and fibrohexamerin (Fhx, previously referred to as P25).

Production of cloned transgenic silkworms by breeding non-diapausing parthenogenetic strains.

Clonal transgenic silkworms are useful for the functional analysis of insect genes and for the production of recombinant proteins. Such silkworms have previously been created using an existing ameiotic parthenogenetic strain. However, the process was labor intensive, and the efficiency of producing transgenic silkworms was very low.

Modular structure, sequence diversification and appropriate nomenclature of seroins produced in the silk glands of Lepidoptera.

Seroins are small lepidopteran silk proteins known to possess antimicrobial activities. Several seroin paralogs and isoforms were identified in studied lepidopteran species and their classification required detailed phylogenetic analysis based on complete and verified cDNA sequences. We sequenced silk gland-specific cDNA libraries from ten species and identified 52 novel seroin cDNAs.

Importance of functional classification in the use of carabids for the environmental risk assessment of the GE crops and other agricultural practices.

Carabids (Coleoptera: Carabidae) seem to be suitable bioindicators of the environmental impacts of novel agrotechnologies, including deployment of the genetically engineered (GE) crops. In this article, we describe our effort to employ carabids in the environmental risk assessment (ERA). GE maize MON88017, its near-isogenic hybrid nontreated or treated with the soil insecticide chlorpyrifos, and two reference hybrids were used to compare three different ways how to utilize carabids in ERA.

Use of Carabids for the Post-Market Environmental Monitoring of Genetically Modified Crops.

Post-market environmental monitoring (PMEM) of genetically modified (GM) crops is required by EU legislation and has been a subject of debate for many years; however, no consensus on the methodology to be used has been reached. We explored the suitability of carabid beetles as surrogates for the detection of unintended effects of GM crops in general PMEM surveillance. Our study combines data on carabid communities from five maize field trials in Central Europe.

Sericin Composition in the Silk of Antheraea yamamai.

The silks produced by caterpillars consist of fibroin proteins that form two core filaments, and sericin proteins that seal filaments into a fiber and conglutinate fibers in the cocoon. Sericin genes are well-known in Bombyx mori (Bombycidae) but have received little attention in other insects. This paper shows that Antheraea yamamai (Saturniidae) contains five sericin genes very different from the three sericin genes of B.

Genome engineering and parthenocloning in the silkworm, Bombyx mori.

Genetic engineering of the silkworm, Bombyx mori, opens door to the production of new kinds of silk and to the use of silkworms as proteosynthetic bioreactors. The insertion of foreign genes into silkworm genome and the control of their expression by diverse promoters have become possible but are not yet efficient enough for commercial use. Several methods of gene targeting are being developed to minimize position effect on transgene expression and facilitate cloning.

Construction and long term preservation of clonal transgenic silkworms using a parthenogenetic strain.

For the functional analysis of insect genes as well as for the production of recombinant proteins for biomedical use, clonal transgenic silkworms are very useful. We examined if they could be produced in the parthenogenetic strain that had been maintained for more than 40years as a female line in which embryogenesis is induced with nearly 100% efficiency by a heat shock treatment of unfertilized eggs. All individuals have identical female genotype.

Risk Assessment of Genetically Engineered Maize Resistant to Diabrotica spp.: Influence on Above-Ground Arthropods in the Czech Republic.

Transgenic maize MON88017, expressing the Cry3Bb1 toxin from Bacillus thuringiensis (Bt maize), confers resistance to corn rootworms (Diabrotica spp.) and provides tolerance to the herbicide glyphosate. However, prior to commercialization, substantial assessment of potential effects on non-target organisms within agroecosystems is required.

Protease inhibitor from insect silk-activities of derivatives expressed in vitro and in transgenic potato.

Several recombinant derivatives of serine protease inhibitor called silk protease inhibitor 2 (SPI2), which is a silk component in Galleria mellonella (Lepidoptera, Insecta), were prepared in the expression vector Pichia pastoris. Both the native and the recombinant protease inhibitors were highly active against subtilisin and proteinase K. The synthetic SPI2 gene with Ala codon in the P1 position was fused with mGFP-5 to facilitate detection of the transgene and its protein product.

Functional conservation and structural diversification of silk sericins in two moth species.

Sericins are hydrophilic structural proteins produced by caterpillars in the middle section of silk glands and layered over fibroin proteins secreted in the posterior section. In the process of spinning, fibroins form strong solid filaments, while sericins seal the pair of filaments into a single fiber and glue the fiber into a cocoon. Galleria mellonella and the previously examined Bombyx mori harbor three sericin genes that encode proteins containing long repetitive regions.

Conservation of a pair of serpin 2 genes and their expression in Amphiesmenoptera.

Silk secreted by the larvae of Hydropsyche angustipennis (Trichoptera) contains serpins HaSerp2A and HaSerp2B that are homologous to serpin 2 known from several lepidopterans and some other insects. The gene HaSerp2A is 2684 bp downstream from the HaSerp2B gene. The genes possess identical exon/intron segmentation (9 exons) and their sequences are nearly identical: only 8 out of 1203 nt differ in the coding region, 4 out of 567 nt in the introns and 2 out of 52 nt in 3' UTR.

Control of larval-pupal-adult molt in the moth Sesamia nonagrioides by juvenile hormone and ecdysteroids.

Sesamia nonagrioides (Lepidoptera: Noctuidae) larvae reared under long day (LD; 16L:8D) conditions pupate after 5 or 6 larval instars, whereas under short day (SD; 12L:12D) conditions they undergo up to 12 additional molts before pupating. This extended period of repeated molting is maintained by high levels of juvenile hormone (JH). Previous work demonstrated that both LD and SD larvae decapitated in the 6th instar pupate but further development is halted.

Gene encoding the prothoracicotropic hormone of a moth is expressed in the brain and gut.

The molts of lepidopteran insects are typically controlled by the brain-derived prothoracicotropic hormone (PTTH) that stimulates ecdysteroidogenesis in the prothoracic glands (PGs). We report here that the larvae and pupae of the moth Sesamia nonagrioides can molt without brain (PGs must be present), suggesting that there might be a secondary source of PTTH. We addressed this issue by characterizing spatial and temporal expression patterns of the PTTH gene.

Molecular evolution of lepidopteran silk proteins: insights from the ghost moth, Hepialus californicus.

Silk production has independently evolved in numerous arthropod lineages, such as Lepidoptera, the moths and butterflies. Lepidopteran larvae (caterpillars) synthesize silk proteins in modified salivary glands and spin silk fibers into protective tunnels, escape lines, and pupation cocoons. Molecular sequence data for these proteins are necessary to determine critical features of their function and evolution.

Circadian control of permethrin-resistance in the mosquito Aedes aegypti.

Daily fluctuation of permethrin-resistance was found in adult mosquito Aedes aegypti, the major vector of dengue viruses in Taiwan. We hypothesized there is a relationship between resistance and the circadian clock. To test our hypothesis we correlated changes in the knock-down time (KT(50)) response to permethrin with the expression of the pyrethroid-resistant gene CYP9M9 and the clock gene period (per) during a 12:12h photoperiodic cycle.

Brain-independent development in the moth Sesamia nonagrioides.

The caterpillars of Sesamia nonagrioides developing under long-day (LD) photoperiod pupate in the 5th or 6th instar whereas under short day (SD) conditions they enter diapause and undergo several extra larval molts. The diapause is terminated within 1-3 instars upon transfer of SD larvae to the LD conditions. Brain removal from the 6th instar larvae promotes pupation followed by imaginal development; however, one third of the SD larvae and 12% of the LD larvae debrained at the start of the instar first undergo 1-2 larval molts.

Structure and expression of the silk adhesive protein Ser2 in Bombyx mori.

Sericins are soluble silk components encoded in Bombyx mori by three genes, of which Ser1 and Ser3 have been characterized. The Ser1 and Ser3 proteins were shown to appear later in the last larval instar as the major sericins of cocoon silk. These proteins are, however, virtually absent in the highly adhesive silk spun prior to cocoon spinning, when the larvae construct a loose scaffold for cocoon attachment.

Peptidase inhibitors from the salivary glands of the cockroach Nauphoeta cinerea.

Inhibitory activity against subtilisin, proteinase K, chymotrypsin and trypsin was detected in the salivary glands and saliva of the cockroach Nauphoeta cinerea (Blattoptera: Blaberidae). Fractionation of the salivary glands extract by affinity chromatography followed by reverse-phase HPLC yielded five subtilisin-inhibiting peptides with molecular masses ranging from 5 to 14 kDa. N-terminal sequences and subsequently full-length cDNAs of inhibitors designated NcPIa and NcPIb were obtained.

Conservation of silk genes in Trichoptera and Lepidoptera.

Larvae of the sister orders Trichoptera and Lepidoptera are characterized by silk secretion from a pair of labial glands. In both orders the silk filament consists of heavy (H)- and light (L)-chain fibroins and in Lepidoptera it also includes a P25 glycoprotein. The L-fibroin and H-fibroin genes of Rhyacophila obliterata and Hydropsyche angustipennis caddisflies have exon/intron structuring (seven exons in L-fibroin and two in H-fibroin) similar to that in their counterparts in Lepidoptera.

Hemolin expression in the silk glands of Galleria mellonella in response to bacterial challenge and prior to cell disintegration.

Hemolin, a member of the immunoglobulin protein superfamily, functions in Lepidoptera as an opsonin in defence against potential pathogens and seems to play a role in tissue morphogenesis. We show that hemolin gene is expressed in several organs of Galleria mellonella larvae, including the nervous system and the silk glands. The expression in the silk glands of the wandering larvae and their isolated abdomens is enhanced within 6h after an injection of bacteria, lipopolysaccharides, or peptidoglycans.