02262nas a2200241   4500008004100000022001400041245009500055210006900150260000800219490000800227520149500235653001201730653002501742653001701767653002301784653002401807653001401831100001701845700000501862700002201867700001801889856011301907       2021                        eng d  a0022-263100aMolecular characterization of the beta(2)-like octopamine receptor of helicoverpa armigera0 aMolecular characterization of the beta2like octopamine receptor   cJUN0 v2543 a<p>Helicoverpa armigera is a devastating polyphagous and cosmopolitan crop pest. There are reports of this insect being resistant to a variety of pesticides raising concern worldwide. The Octopamine (OA) binding beta(2)-like receptor (OAR), a GPCR, is widely distributed in the nervous system of the insect and plays essential roles in the physiology and development and thus is an important target for insecticides. Yet, the molecular characterization of the H. armigera OAR (HarmOAR) and rational design of compounds based on this receptor is lacking. As a first step, we performed multiple sequence alignment of all insect OARs, which revealed that the sequences contained all conserved class A GPCR motifs. Phylogenetic studies showed clade-specific variations in the protein sequences primarily arising owing to differences in the ICL3 loop region. Further, a structural model of HarmOAR was built using the inactive human beta(2)AR as a template. 0.9 mu s atomistic simulations revealed conserved inter helical contacts and water molecules of HarmOAR. The detailed binding of octopamine was studied using molecular docking and 0.3 mu s atomistic simulations. Twenty-two insecticides active against octopamine receptors of other insects were compiled and docked to HarmOAR followed by rescoring with binding free energies to prioritize them for H. armigera. Our study suggests alpha-terpineol to be a good candidate as an insecticide or insect repellent for Helicoverpa armigera.</p>
10adocking10aHelicoverpa armigera10aInsecticides10amolecular dynamics10aOctopamine receptor10aPhylogeny1 aGujar, Nidhi1 a1 aJoshi, Rakesh, S.1 aJoshi, Manali  uhttps://library.ncl.res.in/content/molecular-characterization-beta2-octopamine-receptor-helicoverpa-armigera