Discovering allatostatin type-C receptor specific agonists.

Currently, there is no pesticide available for the selective control of the pine processionary moth (Thaumetopoea pityocampa-specific), and conventional methods typically rely on mechanical techniques such as pheromone traps or broad-spectrum larvicidal chemicals. As climate change increases the range and dispersion capacity of crop and forest pests, outbreaks of the pine processionary occur with greater frequency and significantly impact forestry and public health. Our study is carried out to provide a T. pityocampa-specific pesticide targeting the Allatostatin Type-C Receptor (AlstR-C). We use a combination of computational biology methods, a cell-based screening assay, and in vivo toxicity and side effect assays to identify, for the first time, a series of AlstR-C ligands suitable for use as T. pityocampa-specific insecticides. We further demonstrate that the novel AlstR-C targeted agonists are specific to lepidopteran larvae, with no harmful effects on coleopteran larvae or adults. Overall, our study represents an important initial advance toward an insect GPCR-targeted next-generation pesticide design. Our approach may apply to other invertebrate GPCRs involved in vital metabolic pathways.

Are insect GPCRs ideal next-generation pesticides: opportunities and challenges.

The increasing human population, combined with low inefficiency and adverse effects of available pesticides, has magnified the urgent need of developing next-generation pesticides. Among the available approaches, strategies targeting invertebrate G protein-coupled receptors (GPCRs) are very promising as these receptors are the targets of endogenous neuropeptides/neuromodulators that upon binding to their receptors induce profound changes in insect physiology. Therefore, exploring GPCR regulators has great potential in the development of targeted next-generation pesticides. Despite the great potential of such alternative pesticides, so far there has been only one approved compound, Amitraz, which conveys its anti-pest activity via the GPCR Octopamine receptor. Here, we review the current status of pesticide development, hazards associated with conventional pesticide compounds, alternative strategies that involve next-generation of pesticides, structural features of GPCRs, and opportunities and challenges of targeting the members of this superfamily in invertebrates to develop anti-pest agents. In conclusion, we emphasize that the potential of GPCRs cannot be utilized in full without more genomic and transcriptomic data to improve our understanding of the complex network of peptidergic signaling pathways. We argue how vital it is to obtain three-dimensional (3D) structural data on physiologically important target GPCRs and encourage the readers to use the state of the art in silico methods such as virtual screening for the discovery of new pesticide compounds.