title: Identification of cDNAs encoding two subtypes of vitamin D receptor in flounder, Paralichthys olivaceus.
abstract: cDNAs encoding two subtypes of the vitamin D receptor (VDR) are cloned from a teleost (flounder, Paralichthys olivaceus). This is the first report of VDR subtypes in fish. Flounder VDR (fVDR) a and b share 86% identity at the amino acid level. With human (h), rat, mouse, quail, and Xenopus VDRs, fVDRa shares 72%, 71%, 71%, 69%, and 71% identity, and fVDRb shares 70%, 69%, 69%, 67%, and 68% identity, respectively. The peptide sequences of the DNA-binding domain (DBD) and hormone-binding domain (HBD) of both subtypes have particularly high homology to those of the tetrapods; e.g. 92% identity for DBP and 74% for HBD between fVDRa and hVDR. In an evolutionary tree constructed with peptide sequences of VDRs and related members of the nuclear receptor superfamily, fVDRa and b are more closely related to each other than to other molecules, and situated in the cluster of VDRs at a position which corresponds well with the evolutional position of fish in the vertebrates. Additional independent genome duplication which is thought to have occurred in ray-finned fish phylogeny may explain the existence of two subtypes of VDR in flounder.
authors.affiliation: Metabolism Section, National Research Institute of Aquaculture, Fisheries Agency, Nansei, Mie, 516-0193, Japan. suzukitr@nria.affrc.go.jp
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: N
authors.initials: N
authors.lastname: Suzuki
authors.forename: A S
authors.initials: AS
authors.lastname: Srivastava
authors.forename: T
authors.initials: T
authors.lastname: Kurokawa
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019143:Evolution, Molecular; D005432:Flounder / Q000235:genetics*; D020440:Gene Duplication; D008969:Molecular Sequence Data; D005810:Multigene Family; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis; D018167:Receptors, Calcitriol / Q000145:classification / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
chemical_list: D012333:RNA, Messenger; D018167:Receptors, Calcitriol