Toxin-resistant isoforms of Na+/K+-ATPase in snakes do not closely track dietary specialization on toads.

ABSTRACT: Toads are chemically defended by bufadienolides, a class of cardiotonic steroids that exert toxic effects by binding to and disabling the Na⁺/K⁺-ATPases of cell membranes. Some predators, including a number of snakes, have evolved resistance to the toxic effects of bufadienolides and prey regularly on toads. Resistance in snakes to the acute effects of these toxins is conferred by at least two amino acid substitutions in the cardiotonic steroid binding pocket of the Na⁺/K⁺-ATPase. We surveyed 100 species of snakes from a broad phylogenetic range for the presence or absence of resistance-conferring mutations. We found that such mutations occur in a much wider range of taxa than previously believed. Although all sequenced species known to consume t

SUBMITTER: Mohammadi S 

PROVIDER: S-EPMC5124105 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature