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Antimicrobial peptides in frog poisons constitute a molecular toxin delivery system against predators.

ABSTRACT: Animals using toxic peptides and proteins for predation or defense typically depend on specialized morphological structures, like fangs, spines, or a stinger, for effective intoxication. Here we show that amphibian poisons instead incorporate their own molecular system for toxin delivery to attacking predators. Skin-secreted peptides, generally considered part of the amphibian immune system, permeabilize oral epithelial tissue and enable fast access of cosecreted toxins to the predator's bloodstream and organs. This absorption-enhancing system exists in at least three distantly related frog lineages and is likely to be a widespread adaptation, determining the outcome of predator-prey encounters in hundreds of species.

SUBMITTER: Raaymakers C

PROVIDER: S-EPMC5686178 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Antimicrobial peptides in frog poisons constitute a molecular toxin delivery system against predators.

Raaymakers Constantijn C Verbrugghe Elin E Hernot Sophie S Hellebuyck Tom T Betti Cecilia C Peleman Cindy C Claeys Myriam M Bert Wim W Caveliers Vicky V Ballet Steven S Martel An A Pasmans Frank F Roelants Kim K

Nature communications 20171114 1

Animals using toxic peptides and proteins for predation or defense typically depend on specialized morphological structures, like fangs, spines, or a stinger, for effective intoxication. Here we show that amphibian poisons instead incorporate their own molecular system for toxin delivery to attacking predators. Skin-secreted peptides, generally considered part of the amphibian immune system, permeabilize oral epithelial tissue and enable fast access of cosecreted toxins to the predator's bloodst ...[more]

PMID: 29138448

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