Overview
- Camargos, T.S. et al. (2015) PLoS ONE 10, e0128578.
- Alomone Labs Tf2 Toxin affects the activation of human NaV1.3 channels expressed in Xenopus oocytes.A. Representative traces of NaV1.3 channel currents before (black) and after (green) the application of 1 µM Tf2 Toxin (#STT-050). Tf2 Toxin caused a significant current at a voltage that does not normally activate the channels. Membrane potential was held at -100 mV, and a voltage step to -30 mV was applied every 10 sec. B. Normalized I-V curve. 1 µM Tf2 Toxin (green) shifts the activation of NaV1.3 channels to more negative voltages compared to control (black).
Tf2 Toxin is a β-scorpion peptide toxin originally isolated from the venom of the Brazilian scorpion Tityus fasciolatus. Tf2 Toxin acts as a NaV1.3 channel opener. It shifts human NaV1.3 channel voltage activation towards negative values and effectively opens the channel at resting membrane potentials1. The toxin was also found to open NaV1.9 channels4.
NaV channels are integral membrane proteins that allow movement of Na+ ions across cellular membranes. in response to local membrane depolarization these channels mediate the influx of Na+ ions2,3.
NaV1.3 channel is encoded by the Scn3A gene and is expressed in peripheral nociceptive neurons of dorsal root ganglion, in the developing nervous system and in pancreatic islet cells2. Abnormalities in Scn3A gene expression are associated with epilepsy, mental retardation, autism, and neuropathic pain3.