title: A New Member of Gamma-Conotoxin Family Isolated from Conus princeps Displays a Novel Molecular Target.
abstract: A novel conotoxin, named as PiVIIA, was isolated from the venom of Conus princeps, a marine predatory cone snail collected in the Pacific Southern Coast of Mexico. Chymotryptic digest of the S-alkylated peptide in combination with liquid chromatography coupled to tandem mass spectrometry, were used to define the sequencing of this peptide. Eleven N-terminal amino acids were verified by automated Edman degradation. PiVIIA is a 25-mer peptide (CDAOTHYCTNYWγCCSGYCγHSHCW) with six cysteine residues forming three disulphide bonds, a hydroxyproline (O) and two gamma carboxyglutamic acid (γ) residues. Based on the arrangement of six Cys residues (C-C-CC-C-C), this conotoxin might belong to the O2-superfamily. Moreover, PiVIIA has a conserved motif (-γCCS-) that characterizes γ-conotoxins from molluscivorous Conus. Peptide PiVIIA has 45% sequence identity with γ-PnVIIA-the prototype of this family. Biological activity of PiVIIA was assessed by voltage-clamp recording in rat dorsal root ganglion neurons. Perfusion of PiVIIA in the µM range produces a significant increase in the Ca(2+) currents, without significantly modifying the Na⁺, K⁺ or proton-gated acid sensing ionic currents. These results indicate that PiVIIA is a new conotoxin whose activity deserves further studies to define its potential use as a positive modulator of neuronal activity.
authors: Departamento de Innovación Biomédica, CICESE, Carretera Ensenada-Tijuana 3918, Ensenada, Baja California, C.P. 22860, Mexico. jbernald@cicese.edu.mx.
authors: Johanna
authors: J
authors: Bernáldez
authors: Departamento de Innovación Biomédica, CICESE, Carretera Ensenada-Tijuana 3918, Ensenada, Baja California, C.P. 22860, Mexico. mjimenez@cicese.edu.mx.
authors: Samanta
authors: S
authors: Jiménez
authors: Laboratorio de Espectrometría de Masas, Departamento de Proteómica, Centro de Ingeniería Genética y Biotecnología, Avenida 31 e/158 y 190, Cubanacán, Playa, PO Box 6162. C.P. 10600, La Habana, Cuba. luis.javier@cigb.edu.cu.
authors: Luis Javier
authors: LJ
authors: González
authors: Laboratorio de Espectrometría de Masas, Departamento de Proteómica, Centro de Ingeniería Genética y Biotecnología, Avenida 31 e/158 y 190, Cubanacán, Playa, PO Box 6162. C.P. 10600, La Habana, Cuba. jesus.noda@cigb.edu.cu.
authors: Jesús Noda
authors: JN
authors: Ferro
authors: Instituto de Fisiología, Benemerita Universidad de Puebla, 14 sur 6301, CU, San Manuel, Puebla, Pue, C.P. 72570, Mexico. esoto24@gmail.com.
authors: Enrique
authors: E
authors: Soto
authors: Instituto de Fisiología, Benemerita Universidad de Puebla, 14 sur 6301, CU, San Manuel, Puebla, Pue, C.P. 72570, Mexico. emilio.salceda@gmail.com.
authors: Emilio
authors: E
authors: Salceda
authors: Departamento de Innovación Biomédica, CICESE, Carretera Ensenada-Tijuana 3918, Ensenada, Baja California, C.P. 22860, Mexico. silem@cicese.edu.mx.
authors: Daniela
authors: D
authors: Chávez
authors: Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, UNAM, Juriquilla, Queretaro, C.P. 76230, Mexico. maguilar@unam.mx.
authors: Manuel B
authors: MB
authors: Aguilar
authors: Departamento de Innovación Biomédica, CICESE, Carretera Ensenada-Tijuana 3918, Ensenada, Baja California, C.P. 22860, Mexico. alicea@cicese.mx.
authors: Alexei
authors: A
authors: Licea-Navarro
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015220:Calcium Channels / Q000502:physiology*; D020916:Conotoxins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D052078:Conus Snail; D005260:Female; D005727:Ganglia, Spinal / Q000166:cytology / Q000502:physiology; D008297:Male; D008969:Molecular Sequence Data; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D020318:Rats, Long-Evans
chemical_list: D015220:Calcium Channels; D020916:Conotoxins; D010455:Peptides; C000611861:PiVIIA conotoxin, Conus princeps
keywords: Conus princeps; calcium channel; dorsal root ganglion neurons; gamma-conotoxin; mass spectrometry