The Scorpion Toxin Tf2 from Tityus fasciolatus Promotes Nav1.3 Opening.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 26083731.
- Also identified by DOI 10.1371/journal.pone.0128578 and PMC identifier 4470819.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
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) expressed in Xenopus oocytes are insensitive upon application of 1 μM Tf2. Therefore, the identification of Tf2 represents a unique addition to the repertoire of animal toxins that can be used to investigate Nav channel function.
Medical subject headings
- Insect Proteins
- Ion Channel Gating
- NAV1.3 Voltage-Gated Sodium Channel
- Scorpion Venoms
- Scorpions
- Sodium Channels