Showing papers in "Insect Biochemistry and Molecular Biology in 1997"

TL;DR: These studies provide excellent models to address basic questions in cell biology such as the control of genes in response to sex-specific, mating-regulated and cell type-specific cues and the function and targeting of peptide hormones.

TL;DR: Current knowledge regarding the molecular biology and biopesticidal action of insect and several other types of chitinases is described in this mini-review.

TL;DR: It is suggested that multiple, varying protease-encoding genes are an adaptive mechanism for reducing the deleterious effects of plant protease inhibitors.

TL;DR: The results suggest that a single amino acid change from Leu993 to Phe993 is responsible for the kdr-type resistance in German cockroach.

TL;DR: Results indicate that there are two pro-PO genes in M. sexta, which are coordinately expressed in oenocytoids, and whose products form predominantly heterodimers in plasma.

TL;DR: Two pyrethroid-resistant strains of horn flies were found to be 17- and 688-fold more resistant to permethrin and 11,300-foldMore resistant to cyhalothrin than a susceptible control strain.

TL;DR: The correlation between toxin-binding specificity and 86Rb+ release strongly suggests that the purified 170 kDa APN is the functional receptor A in the H. virescens midgut epithelial cell brush border membranes.

TL;DR: A Helicoverpa armigera larval midgut cDNA library from larvae raised on an artificial, protein-rich, inhibitor-free diet contained very large numbers of serine proteinase positive clones, and mRNA levels corresponding to the highly expressed trypsin and chymotrypsin families were determined.

TL;DR: It is reported here that l(2)mbn cells can be efficiently induced to differentiate in adherent, macrophage-like cells by treatment with 20-hydroxyecdysone, and expression of several regulatory molecules thought to be involved in the immune response is up-regulated by ecdysone.

TL;DR: The sericin 1 primary transcript of the silkworm Bombyx mori is differentially spliced via a tissue- and developmentally-regulated process and the sequence of the sericins 1 and the secondary structure and physiochemical properties of the different regions of the proteins are deduced.

TL;DR: The data suggest that the salivary glands are the site of secretion of endo-beta-1,4-glucanase in R. speratus, and the presence of YEG1 and YEG2 in the salivating glands is suggested to be a common origin for both components.

TL;DR: It is suggested that different P450s may be over-expressed in different resistant strains, and that recombinant expression will be necessary in order to define precisely their individual substrate specificities and ability to metabolize pyrethroids.

TL;DR: It is demonstrated that the resistance-associated L1014F mutation confers a reduction in the sensitivity of house fly sodium channels to pyrethroids that is sufficient to account for the kdr resistance trait.

TL;DR: Resistance has been genetically linked to hscp markers for the strain PEG87, but this strain was found not to carry the L1029H mutation, which suggests that more than one sodium channel mutation may be contributing to pyrethroid resistance in field populations of H. virescens.

TL;DR: The isolation and characterization of four antimicrobial peptides produced by a European bumblebee Bombus pascuorum showed strong anti-Gram-positive activity and some anti-fungal activity, and an N-terminally blocked molecule showed activity against Gram-negative bacteria only.

TL;DR: The open reading frame of a gene encoding a protein homologous to vertebrate fatty acid desaturases has been characterized in Drosophila melanogaster and the possible involvement of the desat product in the biosynthesis of D. melanogasters contact pheromones is discussed.

TL;DR: It is suggested that GOBP1 may be broadly tuned to a class of "green" and floral odors and rGOBP2 is predominantly alpha-helical, both of which are sensitive to pH and to salt concentrations.

TL;DR: The wasp Campoletis sonorensis injects a polydnavirus (CsPDV) along with its egg during parasitization of Heliothis virescens larvae, and the effect of this translational discrimination is to shunt host resources away from larval growth and adult development, which presumably makes them available to the developing endoparasitoid.

TL;DR: B Baculovirus-mediated expression of the CYP6B4v1 protein in lepidopteran cell lines demonstrates that this P450 isozyme metabolizes isopimpinellin, imperatorin, and bergapten at high rates, xanthotoxin and psoralen at intermediate rates and angelicin, sphond in, and trioxsalen only at very low rates.

TL;DR: The results of the analysis of apoptosis by immunofluorescence detection are in complete accord with the histological, ultrastructural and radioimmunoassay data, suggesting that apoptosis is the basic mechanism for programmed cell death of the cells comprising these vital glands.

TL;DR: Comparative Western and Northern blot studies indicate that expression of CYP9A1 in thiodicarb selected populations of tobacco budworm is associated with insecticide resistance and the pattern of restriction fragment length polymorphism (RELP) variation in offspring of single-pair matings demonstrated autosomal inheritance.

TL;DR: Exposure to whole-mount in situ hybridization shows that AgCP mRNA expression is restricted to most or all cells of the posterior midgut, and the potential use of the AgCP promoter for driving the expression of genes that hinder the development of parasites in the mosquito gut is discussed.

TL;DR: It is demonstrated that the AamEcR gene encodes a functional ecdysteroid receptor, and cDNAs encoding three presumed ecdystersoid receptor isoforms that have common DNA and ligand binding domains linked to distinct amino termini are isolated.

TL;DR: Two-dimensional electrophoresis and Western-blotting with antibodies raised against the PBPs of the male revealed more proteins with molecular weight and isoelectric points similar to those of OBPs and confirmed the high level of microdiversity suspected for this family of proteins.

TL;DR: The kinetics of the activation reactions was unusual in that the final levels of phenoloxidase activity varied depending on the initial concentrations of the activating enzyme, not those of the prophenol oxidase.

TL;DR: It is shown that a member of alpha-esterase multigene family, Lc alpha E7, encodes E3, and an Lcalpha E7 cDNA has been isolated from an OP-susceptible strain and expressed in a baculovirus.

TL;DR: The pronounced sequence similarities between cuticular proteins from different insect orders indicate that the conserved regions are functionally important.

TL;DR: The cloned LcEcR gene is functional and can act as an ecdysteroid-dependent transcription factor in mammalian cells, and this pattern parallels the pattern of expression observed for DmEcR mRNAs during Drosophila development.

TL;DR: The lack of eye pigment in the Aedes aegypti THE AUTHORS (white eye) colony was confirmed to be due to a mutation in the kynurenine hydroxylase gene, which catalyzes one of the steps in the metabolic synthesis of ommochrome eye pigments.

TL;DR: The chymotrypsin mRNA, absent in larvae, pupae, males and newly emerged females, reaches detectable levels within 24 h post-emergence and attains a maximum level 3-7 days after emergence, and the deduced amino acid sequence contains several features typical of chymotin proteases, including the catalytic triad of serine proteases and the residues that determine the chymosodium substrate specificity pocket.