title: Molecular cloning of the ecdysone receptor and the retinoid X receptor from the scorpion Liocheles australasiae.
abstract: cDNAs of the ecdysone receptor and the retinoid X receptor were cloned from the Japanese scorpion Liocheles australasiae, and the amino acid sequences were deduced. The full-length cDNA sequences of the L. australasiae ecdysone receptor and the L. australasiae retinoid X receptor were 2881 and 1977 bp in length, respectively, and the open reading frames encoded proteins of 560 and 414 amino acids. The amino acid sequence of the L. australasiae ecdysone receptor was similar to that of the ecdysone receptor-A of the soft tick, Ornithodoros moubata (68%) and to that of the ecdysone receptor-A1 of the lone star tick, Amblyomma americanum (66%), but showed lower similarity to the ecdysone receptors of Orthoptera and Coleoptera (53-57%). The primary sequence of the ligand-binding region of the L. australasiae ecdysone receptor was highly homologous to that of ticks (85-86%). The amino acid sequence of the L. australasiae retinoid X receptor was also homologous to the amino acid sequence of ultraspiracles of ticks (63%) and insects belonging to the orders Orthoptera and Coleoptera (60-64%). The identity of both the L. australasiae ecdysone receptor and the L. australasiae retinoid X receptor to their lepidopteran and dipteran orthologs was less than 50%. The cDNAs of both the L. australasiae ecdysone receptor (L. australasiae ecdysone receptor-A) and the L. australasiae retinoid X receptor were successfully translated in vitro using a rabbit reticulocyte lysate system. An ecdysone analog, ponasterone A, bound to L. australasiae ecdysone receptor-A (K(D) = 4.2 nM), but not to L. australasiae retinoid X receptor. The L. australasiae retinoid X receptor did not enhance the binding of ponasterone A to L. australasiae ecdysone receptor-A, although L. australasiae retinoid X receptor was necessary for the binding of L. australasiae ecdysone receptor-A to ecdysone response elements.
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan. naka@kais.kyoto-u.ac.jp
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Nakagawa
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sakai
authors.forename: Fumie
authors.initials: F
authors.lastname: Magata
authors.forename: Takehiko
authors.initials: T
authors.lastname: Ogura
authors.forename: Masahiro
authors.initials: M
authors.lastname: Miyashita
authors.forename: Hisashi
authors.initials: H
authors.lastname: Miyagawa
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D019295:Computational Biology; D018076:DNA, Complementary; D004305:Dose-Response Relationship, Drug; D004440:Ecdysone / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D024202:Electrophoretic Mobility Shift Assay; D007700:Kinetics; D008024:Ligands; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D011869:Radioligand Assay; D011987:Receptors, Steroid / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D047488:Retinoid X Receptors / Q000737:chemistry / Q000235:genetics*; D012605:Scorpions / Q000737:chemistry*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic
chemical_list: D018076:DNA, Complementary; D008024:Ligands; D011987:Receptors, Steroid; D047488:Retinoid X Receptors; C055469:ecdysone receptor; D004440:Ecdysone