title: Identification and Characterization of a Novel Family of Cysteine-Rich Peptides (MgCRP-I) from Mytilus galloprovincialis.
abstract: We report the identification of a novel gene family (named MgCRP-I) encoding short secreted cysteine-rich peptides in the Mediterranean mussel Mytilus galloprovincialis. These peptides display a highly conserved pre-pro region and a hypervariable mature peptide comprising six invariant cysteine residues arranged in three intramolecular disulfide bridges. Although their cysteine pattern is similar to cysteines-rich neurotoxic peptides of distantly related protostomes such as cone snails and arachnids, the different organization of the disulfide bridges observed in synthetic peptides and phylogenetic analyses revealed MgCRP-I as a novel protein family. Genome- and transcriptome-wide searches for orthologous sequences in other bivalve species indicated the unique presence of this gene family in Mytilus spp. Like many antimicrobial peptides and neurotoxins, MgCRP-I peptides are produced as pre-propeptides, usually have a net positive charge and likely derive from similar evolutionary mechanisms, that is, gene duplication and positive selection within the mature peptide region; however, synthetic MgCRP-I peptides did not display significant toxicity in cultured mammalian cells, insecticidal, antimicrobial, or antifungal activities. The functional role of MgCRP-I peptides in mussel physiology still remains puzzling.
authors.affiliation: Department of Life Sciences, University of Trieste, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Gerdol
authors.affiliation: Muséum National d'Histoire Naturelle, Département Systématique et Evolution, ISyEB Institut (UMR 7205 CNRS/UPMC/MNHN/EPHE), Paris, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Puillandre
authors.affiliation: Department of Life Sciences, University of Trieste, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: De Moro
authors.affiliation: Protein Structure and Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy.
authors.forename: Corrado
authors.initials: C
authors.lastname: Guarnaccia
authors.affiliation: Department of Life Sciences, University of Trieste, Italy.
authors.forename: Marianna
authors.initials: M
authors.lastname: Lucafò
authors.affiliation: Department of Life Sciences, University of Trieste, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Benincasa
authors.affiliation: Protein Structure and Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy.
authors.forename: Ventislav
authors.initials: V
authors.lastname: Zlatev
authors.affiliation: Department of Life Sciences, University of Trieste, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Manfrin
authors.affiliation: Department of Life Sciences, University of Trieste, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Torboli
authors.affiliation: Department of Life Sciences, University of Trieste, Italy.
authors.forename: Piero Giulio
authors.initials: PG
authors.lastname: Giulianini
authors.affiliation: Department of Life Sciences, University of Trieste, Italy.
authors.forename: Gianni
authors.initials: G
authors.lastname: Sava
authors.affiliation: Department of Biology, University of Padova, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Venier
authors.affiliation: Department of Life Sciences, University of Trieste, Italy pallavic@units.it.
authors.forename: Alberto
authors.initials: A
authors.lastname: Pallavicini
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology; D045744:Cell Line, Tumor; D003545:Cysteine / Q000032:analysis*; D030562:Databases, Protein; D004220:Disulfides / Q000737:chemistry; D019143:Evolution, Molecular; D020440:Gene Duplication; D015870:Gene Expression; D023281:Genomics; D006801:Humans; D008969:Molecular Sequence Data; D005810:Multigene Family; D049878:Mytilus / Q000235:genetics*; D010455:Peptides / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D058849:Protein Refolding
chemical_list: D000890:Anti-Infective Agents; D004220:Disulfides; D010455:Peptides; D003545:Cysteine
keywords: antimicrobial peptide; bivalve mollusk; mussel; toxin; transcriptome