title: Multimeric CREB-binding sites in the promoter regions of a family of G-protein-coupled receptors related to the vertebrate galanin and nociceptin/orphanin-FQ receptor families.
abstract: Four related genes encoding a family of G-protein-coupled receptors (GPCRs) have been isolated from the mollusc Lymnaea stagnalis. The coding regions of this family of receptors share 97-99% sequence similarity at both the protein and nucleotide level, and they also share high sequence identity with vertebrate galanin and orphanin-FQ/nociceptin GPCR families. Analysis of the promoter regions reveals shared domains, some of which encode highly conserved repeating units. One 27-bp repeating unit, which encodes a c-AMP response element (CRE) and binds CREB protein, is repeated 14 times in one promoter. In situ hybridization showed expression of these receptors in identified neurons of several behaviourly important networks including those involved in feeding and ion and water regulation. These Lymnaea receptors are likely to represent members of a novel family of invertebrate neuropeptide receptors extensively regulated in response to intracellular signalling cascades.
authors.affiliation: Sussex Centre for Neuroscience, School of Biological Sciences, University of Sussex, Falmer, Brighton, UK.
authors.forename: S E
authors.initials: SE
authors.lastname: Saunders
authors.forename: J F
authors.initials: JF
authors.lastname: Burke
authors.forename: P R
authors.initials: PR
authors.lastname: Benjamin
mesh_terms: D000818:Animals; D001483:Base Sequence; D002490:Central Nervous System / Q000737:chemistry; D003001:Cloning, Molecular; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D019004:Galanin / Q000235:genetics*; D017952:Ganglia, Invertebrate / Q000737:chemistry; D005786:Gene Expression Regulation / Q000502:physiology; D017403:In Situ Hybridization; D008195:Lymnaea; D008969:Molecular Sequence Data; D009474:Neurons / Q000737:chemistry / Q000502:physiology; D018847:Opioid Peptides / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D018013:Receptors, Neuropeptide / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000502:physiology; D000097629:Nociceptin
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D019204:GTP-Binding Proteins; D019004:Galanin; D018847:Opioid Peptides; D012333:RNA, Messenger; D018013:Receptors, Neuropeptide; D000097629:Nociceptin; C413267:Lym-orph receptor