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Title: Hadrurid Scorpion Toxins: Evolutionary Conservation and Selective Pressures
Scorpion toxins are thought to have originated from ancestral housekeeping genes that underwent diversification and neofunctionalization, as a result of positive selection. Our understanding of the evolutionary origin of these peptides is hindered by the patchiness of existing taxonomic sampling. While recent studies have shown phylogenetic inertia in some scorpion toxins at higher systematic levels, evolutionary dynamics of toxins among closely related taxa remain unexplored. In this study, we used new and previously published transcriptomic resources to assess evolutionary relationships of closely related scorpions from the family Hadruridae and their toxins. In addition, we surveyed the incidence of scorpine-like peptides (SLP, a type of potassium channel toxin), which were previously known from 21 scorpion species. We demonstrate that scorpine-like peptides exhibit gene duplications. Our molecular analyses demonstrate that only eight sites of two SLP copies found in scorpions are evolving under positive selection, with more sites evolving under negative selection, in contrast to previous findings. These results show evolutionary conservation in toxin diversity at shallow taxonomic scale.  more » « less
Award ID(s):
1754587
NSF-PAR ID:
10157698
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Toxins
Volume:
11
Issue:
11
ISSN:
2072-6651
Page Range / eLocation ID:
637
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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