Knockdown of an ATP-binding cassette transporter in resistant western corn rootworm larvae partially reverses resistance to eCry3.1Ab protein.

The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, has evolved resistance to nearly every management tactic utilized in the field. This study investigated the resistance mechanisms in a WCR strain resistant to the Bacillus thuringiensis (Bt) protein eCry3.1Ab using dsRNA to knockdown WCR midgut genes previously documented to be associated with the resistance.

Identification of a receptor for the sex pheromone of the vine mealybug, .

The vine mealybug, , is a significant pest of vineyards in all major grape growing regions of the world. This pest causes significant aesthetic damage to berry clusters through its feeding behavior and secretion of "honeydew", which leads to significant decreases in crop marketability. More importantly, the vine mealybug is a vector of several grapevine viruses which are the causal agent of grapevine leafroll disease, one of the most destructive and economically devastating diseases of the grape industry worldwide.

Structure of an antennally-expressed carboxylesterase suggests lepidopteran odorant degrading enzymes are broadly tuned.

Insects rely on the detection of chemical cues present in the environment to guide their foraging and reproductive behaviour. As such, insects have evolved a sophisticated chemical processing system in their antennae comprised of several types of olfactory proteins. Of these proteins, odorant degrading enzymes are responsible for metabolising the chemical cues within the antennae, thereby maintaining olfactory system function.

Improved cryopreservation media formulation reduces costs of maintenance while preserving function of genetically modified insect cells.

Insect cell lines are an invaluable resource that facilitate various fundamental and applied research programs. Genetically engineered insect cell lines, in particular, serve as a platform through which the function of heterologously expressed proteins can be studied. However, a barrier to more widespread utilization and distribution of insect cell lines, genetically modified or not, is the technical and operational challenge associated with traditional cryopreservation methods, including their dependence on the use of liquid nitrogen facilities, animal or human serum products, and relatively high concentrations of permeating cryoprotectants (e.

Sex pheromone receptors of the light brown apple moth, Epiphyas postvittana, support a second major pheromone receptor clade within the Lepidoptera.

Sex pheromones facilitate species-specific sex communication within the Lepidoptera. They are detected by specialised pheromone receptors (PRs), most of which to date fall into a single monophyletic receptor lineage (frequently referred to as "the PR clade") within the odorant receptor (OR) family. Here we investigated PRs of the invasive horticultural pest, Epiphyas postvittana, commonly known as the light brown apple moth.

Identification and functional characterization of the first molluscan neuromedin U receptor in the slug, Deroceras reticulatum.

Neuromedin U (NmU) is a neuropeptide regulating diverse physiological processes. The insect homologs of vertebrate NmU are categorized as PRXamide family peptides due to their conserved C-terminal end. However, NmU homologs have been elusive in Mollusca, the second largest phylum in the animal kingdom.

Crystal structure of Epiphyas postvittana pheromone binding protein 3.

The insect olfactory system operates as a well-choreographed ensemble of molecules which functions to selectively translate volatile chemical messages present in the environment into neuronal impulses that guide insect behaviour. Of these molecules, binding proteins are believed to transport hydrophobic odorant molecules across the aqueous lymph present in antennal sensilla to receptors present in olfactory sensory neurons. Though the exact mechanism through which these proteins operate is still under investigation, these carriers clearly play a critical role in determining what an insect can smell.

Identification and Characterization of GPCRs for Pyrokinin and CAPA Peptides in the Brown Marmorated Stink Bug, (Hemiptera: Pentatomidae).

The brown marmorated stink bug, , is an invasive hemipteran that causes significant economic losses to various agricultural products around the world. Recently, the and genes that express multiple neuropeptides were described in this species. Here we report six and GPCRs including two splice variants, and evaluate their (a) ability to respond to neuropeptides in cell-based assays, and (b) expression levels by RT-PCR.

Functional characterization of odorant receptors from the moth Eriocrania semipurpurella: A comparison of results in the Xenopus oocyte and HEK cell systems.

The Xenopus oocyte and the Human Embryonic Kidney (HEK) 293 cell expression systems are frequently used for functional characterization (deorphanization) of insect odorant receptors (ORs). However, the inherent characteristics of these heterologous systems differ in several aspects, which raises the question of whether the two systems provide comparable results, and how well the results correspond to the responses obtained from olfactory sensory neurons in vivo. Five candidate pheromone receptors were previously identified in the primitive moth Eriocrania semipurpurella (Esem) and their responses were characterized in HEK cells.

Functional characterization of odorant receptors from Lampronia capitella suggests a non-ditrysian origin of the lepidopteran pheromone receptor clade.

The odorant receptors (ORs) of insects are crucial for host and mate recognition. In moths (Lepidoptera), specialized ORs are involved in male detection of the sex pheromone produced by females. Most moth sex pheromones are C-C acetates, alcohols, and aldehydes (Type I pheromones), and most pheromone receptors (PRs) characterized to date are from higher Lepidoptera (Ditrysia), responding to these types of compounds.

Endogenous insensitivity to the Orco agonist VUAA1 reveals novel olfactory receptor complex properties in the specialist fly Mayetiola destructor.

Insect olfactory receptors are routinely expressed in heterologous systems for functional characterisation. It was recently discovered that the essential olfactory receptor co-receptor (Orco) of the Hessian fly, Mayetiola destructor (Mdes), does not respond to the agonist VUAA1, which activates Orco in all other insects analysed to date. Here, using a mutagenesis-based approach we identified three residues in MdesOrco, located in different transmembrane helices as supported by 3D modelling, that confer sensitivity to VUAA1.

Characterization of Odorant Receptors from a Non-ditrysian Moth, Eriocrania semipurpurella Sheds Light on the Origin of Sex Pheromone Receptors in Lepidoptera.

Pheromone receptors (PRs) are essential in moths to detect sex pheromones for mate finding. However, it remains unknown from which ancestral proteins these specialized receptors arose. The oldest lineages of moths, so-called non-ditrysian moths, use short-chain pheromone components, secondary alcohols, or ketones, so called Type 0 pheromones that are similar to many common plant volatiles.

A Sex Pheromone Receptor in the Hessian Fly Mayetiola destructor (Diptera, Cecidomyiidae).

The Hessian fly, Mayetiola destructor Say (Diptera, Cecidomyiidae), is a pest of wheat and belongs to a group of gall-inducing herbivores. This species has a unique life history and several ecological features that differentiate it from other Diptera such as Drosophila melanogaster and blood-feeding mosquitoes. These features include a short, non-feeding adult life stage (1-2 days) and the use of a long-range sex pheromone produced and released by adult females.

The Peripheral Olfactory Repertoire of the Lightbrown Apple Moth, Epiphyas postvittana.

The lightbrown apple moth, Epiphyas postvittana is an increasingly global pest of horticultural crops. Like other moths, E. postvittana relies on olfactory cues to locate mates and oviposition sites.

A novel method to study insect olfactory receptor function using HEK293 cells.

The development of rapid and reliable assays to characterize insect odorant receptors (ORs) and pheromone receptors (PRs) remains a challenge for the field. Typically ORs and PRs are functionally characterized either in vivo in transgenic Drosophila or in vitro through expression in Xenopus oocytes. While these approaches have succeeded, they are not well suited for high-throughput screening campaigns, primarily due to inherent characteristics that limit their ability to screen large quantities of compounds in a short period of time.