Project description:Marine cone snails have attracted researchers from all disciplines but early life stages have received limited attention due to difficulties accessing or rearing juvenile specimens. Here, we document the culture of Conus magus from eggs through metamorphosis to reveal dramatic shifts in predatory feeding behaviour between post-metamorphic juveniles and adult specimens. Adult C. magus capture fish using a set of paralytic venom peptides combined with a hooked radular tooth used to tether envenomed fish. In contrast, early juveniles feed exclusively on polychaete worms using a unique “sting-and-stalk” foraging behaviour facilitated by short, unbarbed radular teeth and a distinct venom repertoire that induces hypoactivity in prey. Our results demonstrate how coordinated morphological, behavioural and molecular changes facilitate the shift from worm- to fish-hunting in C. magus, and showcase juvenile cone snails as a rich and unexplored source of novel venom peptides for ecological, evolutionary and biodiscovery studies.
Project description:Peptide hormones and neuropeptides form a diverse class of signaling molecules that control essential processes in animals. Despite several breakthroughs in peptide discovery, many signaling peptides remain undiscovered. Recently, we demonstrated the use of somatostatin-like toxins from cone snail venom to identify homologous signaling peptides in prey. Here, we demonstrate that this toxin-based approach can be systematically applied to the discovery of other unknown bilaterian signaling peptides. Using large sequencing datasets, we searched for homologies between cone snail toxins and putative peptides from several important model organisms representing the snails’ prey. We identified and confirmed expression of five toxin families that share strong similarities with previously unknown signaling peptides from mollusks and annelids. One of the peptides was also identified in rotifers, brachiopods, platyhelminths, and arthropods, and another was found to be structurally related to crustacean hyperglycemic hormone, a peptide not previously known to exist in Spiralia. Based on several lines of evidence we propose that these signaling peptides not only exist but serve important physiological functions. Finally, we propose that the discovery pipeline developed here can be more broadly applied to other systems in which one organism has evolved molecules to manipulate the physiology of another.
Project description:Peptide hormones and neuropeptides form a diverse class of signaling molecules that control essential processes in animals. Despite several breakthroughs in peptide discovery, many signaling peptides remain undiscovered. Recently, we demonstrated the use of somatostatin-like toxins from cone snail venom to identify homologous signaling peptides in prey. Here, we demonstrate that this toxin-based approach can be systematically applied to the discovery of other unknown bilaterian signaling peptides. Using large sequencing datasets, we searched for homologies between cone snail toxins and putative peptides from several important model organisms representing the snails’ prey. We identified and confirmed expression of five toxin families that share strong similarities with previously unknown signaling peptides from mollusks and annelids. One of the peptides was also identified in rotifers, brachiopods, platyhelminths, and arthropods, and another was found to be structurally related to crustacean hyperglycemic hormone, a peptide not previously known to exist in Spiralia. Based on several lines of evidence we propose that these signaling peptides not only exist but serve important physiological functions. Finally, we propose that the discovery pipeline developed here can be more broadly applied to other systems in which one organism has evolved molecules to manipulate the physiology of another.
Project description:Peptide hormones and neuropeptides form a diverse class of signaling molecules that control essential processes in animals. Despite several breakthroughs in peptide discovery, many signaling peptides remain undiscovered. Recently, we demonstrated the use of somatostatin-like toxins from cone snail venom to identify homologous signaling peptides in prey. Here, we demonstrate that this toxin-based approach can be systematically applied to the discovery of other unknown bilaterian signaling peptides. Using large sequencing datasets, we searched for homologies between cone snail toxins and putative peptides from several important model organisms representing the snails’ prey. We identified and confirmed expression of five toxin families that share strong similarities with previously unknown signaling peptides from mollusks and annelids. One of the peptides was also identified in rotifers, brachiopods, platyhelminths, and arthropods, and another was found to be structurally related to crustacean hyperglycemic hormone, a peptide not previously known to exist in Spiralia. Based on several lines of evidence we propose that these signaling peptides not only exist but serve important physiological functions. Finally, we propose that the discovery pipeline developed here can be more broadly applied to other systems in which one organism has evolved molecules to manipulate the physiology of another.
Project description:Using proteomics methods, we determined the full sequences of three conodipines (Cdpi-P1, -P2 and -P3). Conodipine-P1-3 have conserved consensus catalytic domain residues, including the Asp/His dyad. The activities of the native Conodipine-Ps were evaluated by conventional colorimetric and by MS-based methods, which provide the first detailed cone snail venom conodipine activity monitored by mass spectrometry. Conodipines can have medicinal applications such inhibition of cancer proliferation, bacterial and viral infections among others.
Project description:Daptomycin-Resistance Mechanisms in Clinically-Derived Staphylococcus aureus Strains Assessed by a Combined Transcriptomics and Proteomics Approach