Venomous auger snail Hastula (Impages) hectica (Linnaeus, 1758): Molecular phylogeny, foregut anatomy and comparative toxinology

Department of Biology, University of Utah, Salt Lake City, Utah, United States
Journal of Experimental Zoology Part B Molecular and Developmental Evolution (Impact Factor: 2.31). 12/2007; 308B(6):744 - 756. DOI: 10.1002/jez.b.21195
Source: PubMed


The >10,000 living venomous marine snail species [superfamily Conoidea (Fleming, 1822)] include cone snails (Conus), the overwhelming focus of research. Hastula hectica (Linnaeus, 1758), a venomous snail in the family Terebridae (Mörch, 1852) was comprehensively investigated. The Terebridae comprise a major monophyletic group within Conoidea. H. hectica has a striking radular tooth to inject venom that looks like a perforated spear; in Conus, the tooth looks like a hypodermic needle. H. hectica venom contains a large complement of small disulfide-rich peptides, but with no apparent overlap with Conus in gene superfamilies expressed. Although Conus peptide toxins are densely post-translationally modified, no post-translationally modified amino acids were found in any Hastula venom peptide. The results suggest that different major lineages of venomous molluscs have strikingly divergent toxinological and venom-delivery strategies. J. Exp. Zool. (Mol. Dev. Evol.) 308B:744–756, 2007. © 2007 Wiley-Liss, Inc.

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Available from: Francisco Heralde
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    • "While the venoms of Conus species have been rigorously investigated, those of other venomous snails remain largely unstudied. A recent investigation of the venomous Auger snail Hastula hectica revealed several venom peptides (termed augerpeptides) similar to those found in Conus venom as well as various venom gland transcripts apparently encoding other venom peptides [64]. Of the few augerpeptides identified, no overlap with conotoxins has so far been reported. "
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    ABSTRACT: Animal venoms represent a vast library of bioactive peptides and proteins with proven potential, not only as research tools but also as drug leads and therapeutics. This is illustrated clearly by marine cone snails (genus Conus), whose venoms consist of mixtures of hundreds of peptides (conotoxins) with a diverse array of molecular targets, including voltage- and ligand-gated ion channels, G-protein coupled receptors and neurotransmitter transporters. Several conotoxins have found applications as research tools, with some being used or developed as therapeutics. The primary objective of this study was the large-scale discovery of conotoxin sequences from the venom gland of an Australian cone snail species, Conus victoriae. Using cDNA library normalization, high-throughput 454 sequencing, de novo transcriptome assembly and annotation with BLASTX and profile hidden Markov models, we discovered over 100 unique conotoxin sequences from 20 gene superfamilies, the highest diversity of conotoxins so far reported in a single study. Many of the sequences identified are new members of known conotoxin superfamilies, some help to redefine these superfamilies and others represent altogether new classes of conotoxins. In addition, we have demonstrated an efficient combination of methods to mine an animal venom gland and generate a library of sequences encoding bioactive peptides.
    Full-text · Article · Feb 2014 · PLoS ONE
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    • "In coniids, the hypodermic type of radula is found in fishhunting cones (Olivera 1997) while a typical hypodermic type radula, enrolled, with a wide opening at the base is found in the terebrid, Hastula hectica (Imperial et al. 2007); thus radular structure may define the likely prey to a particular snail. The emergence of the central tooth to the Gemmula radulae suggests a prey-specificity that could be validated by the polychaete feeding challenge. "

    Full-text · Dataset · May 2013
    • "To a lesser extent, species in the small major clade of Conus, may also contain several novel conotoxins, as suggested by an original Cys-pattern (XIII) found in the species C. delessertii (Aguilar et al. 2005). In addition to the family Conidae, original toxins have already been reported in several other species of Conoidea, such as Polystira albida (Lopez-Vera et al. 2004; Rojas et al. 2008), Gemmula periscelida (Lopez-Vera et al. 2004), G. speciosa, G. sogodensis, G. diomedea, G. kieneri (Heralde et al. 2008), Lophiotoma olangoensis (Watkins et al. 2006), Terebra subulata (Imperial et al. 2003), Hastula hectica (Imperial et al. 2007) and Crassispira cerithina (Cabang et al. 2011). Furthermore, taxonomic surveys (Bouchet et al. 2009) and phylogenetic analyses (Puillandre et al. 2011) suggest that the superfamily Conoidea actually comprises a number of deeply divergent clades, whose species diversity is currently largely underestimated . "
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    ABSTRACT: Conopeptides are toxins expressed in the venom duct of cone snails (Conoidea, Conus). These are mostly well-structured peptides and mini-proteins with high potency and selectivity for a broad range of cellular targets. In view of these properties, they are widely used as pharmacological tools and many are candidates for innovative drugs. The conopeptides are primarily classified into superfamilies according to their peptide signal sequence, a classification that is thought to reflect the evolution of the multigenic system. However, this hypothesis has never been thoroughly tested. Here we present a phylogenetic analysis of 1,364 conopeptide signal sequences extracted from GenBank. The results validate the current conopeptide superfamily classification, but also reveal several important new features. The so-called "cysteine-poor" conopeptides are revealed to be closely related to "cysteine-rich" conopeptides; with some of them sharing very similar signal sequences, suggesting that a distinction based on cysteine content and configuration is not phylogenetically relevant and does not reflect the evolutionary history of conopeptides. A given cysteine pattern or pharmacological activity can be found across different superfamilies. Furthermore, a few conopeptides from GenBank do not cluster in any of the known superfamilies, and could represent yet-undefined superfamilies. A clear phylogenetically based classification should help to disentangle the diversity of conopeptides, and could also serve as a rationale to understand the evolution of the toxins in the numerous other species of conoideans and venomous animals at large.
    No preview · Article · Jul 2012 · Journal of Molecular Evolution
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