These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Structural adaptability in the ligand-binding pocket of the ecdysone hormone receptor.
    Author: Billas IM, Iwema T, Garnier JM, Mitschler A, Rochel N, Moras D.
    Journal: Nature; 2003 Nov 06; 426(6962):91-6. PubMed ID: 14595375.
    Abstract:
    The ecdysteroid hormones coordinate the major stages of insect development, notably moulting and metamorphosis, by binding to the ecdysone receptor (EcR); a ligand-inducible nuclear transcription factor. To bind either ligand or DNA, EcR must form a heterodimer with ultraspiracle (USP), the homologue of retinoid-X receptor. Here we report the crystal structures of the ligand-binding domains of the moth Heliothis virescens EcR-USP heterodimer in complex with the ecdysteroid ponasterone A and with a non-steroidal, lepidopteran-specific agonist BYI06830 used in agrochemical pest control. The two structures of EcR-USP emphasize the universality of heterodimerization as a general mechanism common to both vertebrates and invertebrates. Comparison of the EcR structures in complex with steroidal and non-steroidal ligands reveals radically different and only partially overlapping ligand-binding pockets that could not be predicted by molecular modelling and docking studies. These findings offer new perspectives for the design of insect-specific, environmentally safe insecticides. The concept of a ligand-dependent binding pocket in EcR provides an insight into the moulding of nuclear receptors to their ligand, and has potential applications for human nuclear receptors.
    [Abstract] [Full Text] [Related] [New Search]