title: Sequencing and structural homology modeling of the ecdysone receptor in two chrysopids used in biological control of pest insects.
abstract: In insects, the process of molting and metamorphosis are mainly regulated by a steroidal hormone 20-hydroxyecdysone (20E) and its analogs (ecdysteroids) that specifically bind to the ecdysone receptor ligand-binding domain (EcR-LBD). Currently, several synthetic non-steroidal ecdysone agonists, including tebufenozide, are commercially available as insecticides. Tebufenozide exerts its activity by binding to the 20E-binding site and thus activating EcR permanently. It appears that subtle differences in the architecture among LBDs may underpin the differential binding affinity of tebufenozide across taxonomic orders. In brief, first we demonstrated the harmlessness of tebufenozide towards Chrysoperla externa (Ce). Then, a molecular analysis of EcR-LBD of two neuropteran insects Chrysoperla carnea and Ce was presented. Finally, we constructed a chrysopid in silico homology model docked ponasterone A (PonA) and tebufenozide into the binding pocket and analyzed the amino acids indentified as critical for binding to PonA and tebufenozide. Due to a restrict extent in the cavity at the bottom of the ecdysone-binding pocket a steric clash occurred upon docking of tebufenozide. The absence of harm biological effect and the docking results suggest that tebufenozide is prevented of any deleterious effects on chrysopids.
authors.affiliation: Laboratory of Agrozoology, Department of Crop Protection, Ghent University, 9000 Ghent, Belgium. mzotti.faem@ufpel.tche.br
authors.forename: Moises João
authors.initials: MJ
authors.lastname: Zotti
authors.forename: Olivier
authors.initials: O
authors.lastname: Christiaens
authors.forename: Pierre
authors.initials: P
authors.lastname: Rougé
authors.forename: Anderson Dionei
authors.initials: AD
authors.lastname: Grutzmacher
authors.forename: Paulo Dejalma
authors.initials: PD
authors.lastname: Zimmer
authors.forename: Guy
authors.initials: G
authors.lastname: Smagghe
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D019295:Computational Biology / Q000379:methods; D004440:Ecdysone / Q000819:agonists / Q000378:metabolism; D004441:Ecdysterone / Q000031:analogs & derivatives / Q000494:pharmacology; D006834:Hydrazines / Q000378:metabolism / Q000494:pharmacology; D007313:Insecta / Q000187:drug effects* / Q000502:physiology; D007306:Insecticides / Q000378:metabolism / Q000494:pharmacology; D007605:Juvenile Hormones / Q000378:metabolism / Q000494:pharmacology; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D010572:Pest Control, Biological / Q000379:methods*; D011987:Receptors, Steroid / Q000737:chemistry / Q000187:drug effects / Q000235:genetics*
chemical_list: D006834:Hydrazines; D007306:Insecticides; D007605:Juvenile Hormones; D011987:Receptors, Steroid; C055469:ecdysone receptor; D004440:Ecdysone; D004441:Ecdysterone; C008999:ponasterone A; C082026:tebufenozide