title: Teleocortin: A Novel Member of the CRH Family in Teleost Fish.
abstract: The CRH family of neuropeptides, including CRH and urocortins, plays pivotal roles in the regulation of physiological and behavioral stress responses in vertebrates. In this study, we identified a previously undescribed member of the CRH family of peptides in a teleost fish species (medaka; Oryzias latipes) and named this peptide teleocortin (Tcn). Medaka Tcn is a 41-amino acid polypeptide derived from the C terminus of a larger precursor protein that is encoded by a 2-exon gene, thus sharing common structural features with known CRH family peptides. tcn was found exclusively in teleost fish. Phylogenetic analysis suggested that tcn probably has an ancient origin but was lost from the tetrapod lineage shortly after the divergence of the teleost and tetrapod lineages. In the medaka brain, tcn was expressed in nuclei of the telencephalon, preoptic area, hypothalamus, tegmentum, and isthmic region. Because none of these nuclei have been implicated in the control of ACTH secretion from the pituitary, Tcn may exert its effects centrally in the brain rather than via stimulation of the pituitary-adrenal/interrenal axis. Most, if not all, tcn-expressing neurons also expressed crh, suggesting that Tcn and Crh share common physiological functions. Moreover, Tcn activated Crh receptors 1 and 2 with equivalent or slightly higher potency than Crh, further suggesting that these peptides share common functions. Taken together, these data identified Tcn as a novel, teleost-specific member of the CRH family of peptides that may act centrally with Crh to regulate physiological and behavioral stress responses.
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Hosono
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Kikuchi
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Miyanishi
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Towako
authors.initials: T
authors.lastname: Hiraki-Kajiyama
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Takeuchi
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Nakasone
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Maehiro
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Kataaki
authors.initials: K
authors.lastname: Okubo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000378:metabolism; D003001:Cloning, Molecular; D003346:Corticotropin-Releasing Hormone / Q000235:genetics*; D029941:Fish Proteins / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D008969:Molecular Sequence Data; D005810:Multigene Family; D009479:Neuropeptides / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology*; D009990:Oryzias / Q000235:genetics*; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution; D054832:Urocortins / Q000235:genetics
chemical_list: D029941:Fish Proteins; D009479:Neuropeptides; D054832:Urocortins; D003346:Corticotropin-Releasing Hormone