title: Molecular characterization and expression of mandibular organ-inhibiting hormone, a recently discovered neuropeptide involved in the regulation of growth and reproduction in the crab Cancer pagurus.
abstract: Methyl farnesoate, the crustacean juvenoid, is synthesized and secreted from the mandibular organs of crustaceans under the negative control of the sinus gland-derived mandibular organ-inhibiting hormone (MO-IH). Previously we isolated and sequenced two isoforms, MO-IH-1 and MO-IH-2, differing by just one amino acid, from sinus glands of the edible crab, Cancer pagurus. We now report the isolation of cDNAs encoding MO-IH-1 and MO-IH-2 by a combination of reverse-transcriptase-mediated PCR in conjunction with 5' and 3' rapid amplification of cDNA ends ('RACE'). Full-length clones of MO-IH-1 and MO-IH-2 encoded a 34-residue putative signal peptide and the mature 78-residue MO-IH sequences. Northern blot analysis of various tissues showed that MO-IH expression is confined to the X-organ (a cluster of perikarya within the eye). Southern blot analysis indicated that there are approx. 10 copies of the gene for MO-IH in C. pagurus. Additional Southern blotting experiments detected MO-IH-hybridizing bands in another Cancer species, C. antennarius. In support of this, an HPLC-radioimmunoassay analysis of sinus gland extracts of C. antennarius and C. magister also revealed MO-IH-like immunoreactivity.
authors.affiliation: School of Biological Sciences, University of Liverpool, Life Sciences Building, Crown Street, Liverpool L69 7ZB, U.K.
authors.forename: C
authors.initials: C
authors.lastname: Tang
authors.forename: W
authors.initials: W
authors.lastname: Lu
authors.forename: G
authors.initials: G
authors.lastname: Wainwright
authors.forename: S G
authors.initials: SG
authors.lastname: Webster
authors.forename: H H
authors.initials: HH
authors.lastname: Rees
authors.forename: P C
authors.initials: PC
authors.lastname: Turner
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D003386:Brachyura / Q000033:anatomy & histology / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D003001:Cloning, Molecular; D016208:Databases, Factual; D005260:Female; D018628:Gene Dosage; D007301:Insect Hormones / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D009928:Organ Specificity; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D011863:Radioimmunoassay; D012098:Reproduction / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D007301:Insect Hormones; D009479:Neuropeptides; D012333:RNA, Messenger; C100331:mandibular organ-inhibiting hormone 1; C100332:mandibular organ-inhibiting hormone 2