Article

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

Journal of Experimental Zoology Part B Molecular and Developmental Evolution (Impact Factor: 2.12). 12/2007; 308B(6):744 - 756. DOI: 10.1002/jez.b.21195
Source: PubMed

ABSTRACT 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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