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Toxin-resistant sodium channels: parallel adaptive evolution across a complete gene family.
This study shows how 4 taxonomically diverse species of pufferfishes each evolved resistance to the guanidinium toxins tetrodotoxin and saxitoxin via parallel amino acid replacements across all 8 sodium channels present in teleost fish genomes. Expand
Old gene duplication facilitates origin and diversification of an innovative communication system—twice
It is shown that Scn4aa co-option and rapid sequence evolution were tightly coupled to the two origins of electric organ, providing strong evidence that ScN4aa contributed to parallel innovations underlying the evolutionary diversification of each electric fish group. Expand
EOD modulations of brown ghost electric fish: JARs, chirps, rises, and dips
It is proposed that NMDA-receptor dependent increases in EOD frequency during the JAR adaptively shift the EODfrequency to a new value to avoid jamming by another fish and that such increases in NMT frequency during social encounters may be advantageous since social dominance seems to be positively correlated with EOD Frequency in both sexes. Expand
Diversity of sexual dimorphism in electrocommunication signals and its androgen regulation in a genus of electric fish, Apteronotus
In both chirping and electric organ discharge frequency, evolutionary changes in the presence or direction of sexual dimorphism have been accompanied and perhaps caused byChanges in the androgen regulation of theElectric organ discharge. Expand
Changes in signalling during agonistic interactions between male weakly electric knifefish, Apteronotus leptorhynchus
Signals emitted preceding and during combat can aid in sequential assessment of opponent quality and motivation. Signal reliability can be maintained by physical constraints, by costs of productionExpand
Evolution of sodium channels predates the origin of nervous systems in animals
A phylogeny infer ancestral states of the ion selectivity filter and show that this state has been retained in the choanoflagellate and placozoan channels and identifies key gene duplications and losses and shows convergent amino acid replacements at important points along the animal lineage. Expand
Sodium channel genes and the evolution of diversity in communication signals of electric fishes: convergent molecular evolution.
Changes in the expression and sequence of the same gene are associated with the independent evolution of signal complexity, and appear to be evolving under positive selection in both lineages. Expand
Adaptive evolution of voltage-gated sodium channels: The first 800 million years
  • H. Zakon
  • Biology, Medicine
  • Proceedings of the National Academy of Sciences
  • 22 June 2012
Voltage-gated Na+-permeable (Nav) channels form the basis for electrical excitability in animals and show adaptive sequence evolution for increasing diversity in communication signals, in protection against lethal Nav channel toxins, and in specialized habitats. Expand
Gene Duplications and Evolution of Vertebrate Voltage-Gated Sodium Channels
The findings from phylogenetic analysis and chromosomal mapping of Danio rerio genes indicate that tandem duplications are an unlikely mechanism for generation of the extant teleost SCNA genes, and analyses of other closely mapped genes in D. rerio support the hypothesis that a whole-genome duplication was involved in expansion of the SCNA gene family in teleosts. Expand
Effects of sex, sensitivity and status on cue recognition in the weakly electric fish Apteronotus leptorhynchus
Maintaining a stable social organization necessitates that animals recognize their own dominance status relative to the status of other group members. The weakly electric brown ghost knifefish emitsExpand