title: The spasmodic peptide defines a new conotoxin superfamily.
abstract: We purified and characterized a peptide from the venom of Conus textile that makes normal mice assume the phenotype of a well-known mutant, the spasmodic mouse. This "spasmodic" peptide has 27 amino acids, including two gamma-carboxyglutamate (Gla) residues. A cDNA clone encoding the precursor for the peptide was identified; a gamma-carboxylation recognition signal sequence (gamma-CRS) is present in the -1 --> -20 region of the peptide precursor. Both the gamma-CRS and the position of the Gla residues in the mature toxin are notably different from other Gla-containing conopeptides. The spasmodic peptide has a novel disulfide framework and distinct signal sequence which together define a new P-superfamily of conopeptides. A cDNA encoding another member of the P-superfamily was identified from a different species, Conus gloriamaris.
authors.affiliation: Department of Biology, University of Utah, Salt Lake City, Utah 84112, USA.
authors.forename: M B
authors.initials: MB
authors.lastname: Lirazan
authors.forename: D
authors.initials: D
authors.lastname: Hooper
authors.forename: G P
authors.initials: GP
authors.lastname: Corpuz
authors.forename: C A
authors.initials: CA
authors.lastname: Ramilo
authors.forename: P
authors.initials: P
authors.lastname: Bandyopadhyay
authors.forename: L J
authors.initials: LJ
authors.lastname: Cruz
authors.forename: B M
authors.initials: BM
authors.lastname: Olivera
mesh_terms: D015055:1-Carboxyglutamic Acid / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001522:Behavior, Animal / Q000187:drug effects*; D003001:Cloning, Molecular; D020916:Conotoxins / Q000008:administration & dosage / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D005399:Fishes; D007276:Injections, Intraventricular; D051379:Mice; D008969:Molecular Sequence Data; D009043:Motor Activity / Q000187:drug effects*; D010446:Peptide Fragments; D010455:Peptides / Q000008:administration & dosage / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship
chemical_list: D020916:Conotoxins; C059360:Conus textile toxin; D010446:Peptide Fragments; D010455:Peptides; C404911:spasmodic peptide, Conus; D015055:1-Carboxyglutamic Acid