title: Recruitment of glycosyl hydrolase proteins in a cone snail venomous arsenal: further insights into biomolecular features of Conus venoms.
abstract: Cone snail venoms are considered an untapped reservoir of extremely diverse peptides, named conopeptides, displaying a wide array of pharmacological activities. We report here for the first time, the presence of high molecular weight compounds that participate in the envenomation cocktail used by these marine snails. Using a combination of proteomic and transcriptomic approaches, we identified glycosyl hydrolase proteins, of the hyaluronidase type (Hyal), from the dissected and injectable venoms ("injectable venom" stands for the venom variety obtained by milking of the snails. This is in contrast to the "dissected venom", which was obtained from dissected snails by extraction of the venom glands) of a fish-hunting cone snail, Conus consors (Pionoconus clade). The major Hyal isoform, Conohyal-Cn1, is expressed as a mixture of numerous glycosylated proteins in the 50 kDa molecular mass range, as observed in 2D gel and mass spectrometry analyses. Further proteomic analysis and venom duct mRNA sequencing allowed full sequence determination. Additionally, unambiguous segment location of at least three glycosylation sites could be determined, with glycans corresponding to multiple hexose (Hex) and N-acetylhexosamine (HexNAc) moieties. With respect to other known Hyals, Conohyal-Cn1 clearly belongs to the hydrolase-type of Hyals, with strictly conserved consensus catalytic donor and positioning residues. Potent biological activity of the native Conohyals could be confirmed in degrading hyaluronic acid. A similar Hyal sequence was also found in the venom duct transcriptome of C. adamsonii (Textilia clade), implying a possible widespread recruitment of this enzyme family in fish-hunting cone snail venoms. These results provide the first detailed Hyal sequence characterized from a cone snail venom, and to a larger extent in the Mollusca phylum, thus extending our knowledge on this protein family and its evolutionary selection in marine snail venoms.
authors.affiliation: These authors contributed equally to this work..
authors.forename: Aude
authors.initials: A
authors.lastname: Violette
authors.affiliation: Atheris Laboratories, Case postale 314, CH-1233 Bernex-Geneva, Switzerland.
authors.forename: Adrijana
authors.identifier: 0000-0001-9854-9955
authors.initials: A
authors.lastname: Leonardi
authors.affiliation: Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia.
authors.forename: David
authors.initials: D
authors.lastname: Piquemal
authors.affiliation: Skuldtech, Cap Delta, 1682, rue de la Valsière, 34790 Grabels, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Terrat
authors.affiliation: These authors contributed equally to this work..
authors.forename: Daniel
authors.initials: D
authors.lastname: Biass
authors.affiliation: These authors contributed equally to this work..
authors.forename: Sébastien
authors.initials: S
authors.lastname: Dutertre
authors.affiliation: Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia.
authors.forename: Florian
authors.initials: F
authors.lastname: Noguier
authors.affiliation: Skuldtech, Cap Delta, 1682, rue de la Valsière, 34790 Grabels, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Ducancel
authors.affiliation: These authors contributed equally to this work..
authors.forename: Reto
authors.initials: R
authors.lastname: Stöcklin
authors.affiliation: Atheris Laboratories, Case postale 314, CH-1233 Bernex-Geneva, Switzerland.
authors.forename: Igor
authors.identifier: 0000-0003-0203-0708
authors.initials: I
authors.lastname: Križaj
authors.affiliation: These authors contributed equally to this work..
authors.forename: Philippe
authors.initials: P
authors.lastname: Favreau
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D052078:Conus Snail / Q000201:enzymology* / Q000378:metabolism; D020869:Gene Expression Profiling; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000378:metabolism*; D006031:Glycosylation; D006821:Hyaluronoglucosaminidase / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008970:Molecular Weight; D008978:Mollusk Venoms / Q000201:enzymology* / Q000378:metabolism; D009699:N-Glycosyl Hydrolases / Q000737:chemistry / Q000378:metabolism; D010802:Phylogeny; D017433:Protein Structure, Secondary; D040901:Proteomics / Q000379:methods; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
chemical_list: D008978:Mollusk Venoms; D012333:RNA, Messenger; D006026:Glycoside Hydrolases; D006821:Hyaluronoglucosaminidase; D009699:N-Glycosyl Hydrolases