The Scorpion Toxin Tf2 from Tityus fasciolatus Promotes Nav1.3 Opening.
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ABSTRACT:
SUBMITTER: Camargos TS
PROVIDER: S-EPMC4470819 | biostudies-literature | 2015
REPOSITORIES: biostudies-literature
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The Scorpion Toxin Tf2 from Tityus fasciolatus Promotes Nav1.3 Opening.
Camargos Thalita S TS Bosmans Frank F Bosmans Frank F Rego Solange C SC Mourão Caroline B F CB Schwartz Elisabeth F EF
PloS one 20150617 6
We identified Tf2, the first β-scorpion toxin from the venom of the Brazilian scorpion Tityus fasciolatus. Tf2 is identical to Tb2-II found in Tityus bahiensis. We found that Tf2 selectively activates human (h)Nav1.3, a neuronal voltage-gated sodium (Nav) subtype implicated in epilepsy and nociception. Tf2 shifts hNav1.3 activation voltage to more negative values, thereby opening the channel at resting membrane potentials. Seven other tested mammalian Nav channels (Nav1.1-1.2; Nav1.4-1.8) expres ...[more]
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