title: A protein from the salivary glands of the giant Amazon leech with high sequence homology to a nicotinic acetylcholine receptor subunit.
abstract: A gene coding for a soluble protein with homology to the beta subunit of the nicotinic acetylcholine receptor from goldfish was isolated from a cDNA library of Haementeria ghilianii salivary glands. Comparison of the leech protein sequence with the database showed that the N terminus has high homology with the extracellular portion of acetylcholine receptor beta subunits, whilst the C terminus, highly charged, has homology to proteins which may be involved in chelating divalent cations. The leech protein was expressed in mammalian cells and the product compared to the native protein. Both proteins are glycosylated and form polymers which are disrupted by heat but not by reducing agents. A role for this protein in salivary gland secretion is suggested.
authors.affiliation: E. Merck Laboratory, MRC Collaborative Centre, London, U.K.
authors.forename: S
authors.initials: S
authors.lastname: Salgueiro
authors.forename: S
authors.initials: S
authors.lastname: Potts
authors.forename: E A
authors.initials: EA
authors.lastname: McIlgorm
authors.forename: K H
authors.initials: KH
authors.lastname: Ansell
authors.forename: J
authors.initials: J
authors.lastname: Hemberger
authors.forename: D
authors.initials: D
authors.lastname: Güssow
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D015723:Gene Library; D006054:Goldfish; D006454:Hemoglobins / Q000737:chemistry; D007865:Leeches; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D011978:Receptors, Nicotinic / Q000737:chemistry* / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012471:Salivary Proteins and Peptides / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification; D012550:Schistosoma mansoni / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D006454:Hemoglobins; D046911:Macromolecular Substances; D011978:Receptors, Nicotinic; D012471:Salivary Proteins and Peptides