Cat #: STH-100
Alternative Name μ-Theraphotoxin-Hh2a, Huwentoxin IV
This product is freeze dried. All water molecules have been removed.
Every lot is tried & tested in a relevant biological assay.
Origin Haplopelma schmidti (Chinese bird spider, Ornithictonus huwenum).
Source Synthetic peptide
MW: 4106 Da.
Purity: >99% (HPLC)
Effective concentration 20-500 nM.
Modifications Disulfide bonds between Cys2-Cys17, Cys9-Cys24, and Cys16-Cys31. Ile35 - C-terminal amidation.
Molecular formula C174H278N52O51S6.
CAS No.: 526224-73-7
Activity Huwentoxin-IV specifically inhibits the neuronal tetrodotoxin-sensitive (TTX-S) voltage-gated Na+ channel (IC50 = 30 nM) in adult rat dorsal root ganglion neurons, while having no significant effect on the tetrodotoxin-resistant (TTX-R) voltage-gated Na+ channel1-3.
Shipping and storage Shipped at room temperature. Product as supplied can be stored intact at room temperature for several weeks. For longer periods, it should be stored at -20°C.
Solubility Any aqueous buffer. Centrifuge all product preparations before use (10000 x g 5 min).
Storage of solutions Up to two weeks at 4°C or three months at -20°C.
Alomone Labs Huwentoxin-IV inhibits NaV1.7 channels heterologously expressed in Xenopus oocytes.A. Time course of current inhibition by 500 nM Huwentoxin-IV (#STH-100) (green). Currents were elicited by a voltage ramp between -80 mV to +20 mV (60 ms) every 10 seconds from holding potential of -80 mV. B. Example traces of current response to voltage ramp application before (black) and during (green) 500 nM Huwentoxin-IV application.
Huwentoxin-IV is a 35 amino acid peptidyl toxin isolated from the tarantula Haplopelma schmidti venom and its structure represents a typical cystine knot motif1. Huwentoxin-IV acts selectively on tetrodotoxin-sensitive (TTX-S) voltage-gated Na+ channels, with an IC50 of 30 nM in rat DRG neurons. It preferentially inhibits central neuronal voltage-gated Na+ channel subtypes: hNaV1.7 (IC50 of 26 nM), rNaV1.2 (IC50 of 150 nM), and rNaV1.3 (IC50 of 338 nM), compared with muscle subtypes rNaV1.4 and hNaV1.5 (IC50 is > 10 µM)2. Huwentoxin-IV inhibits Na+ channels by trapping the voltage sensor of domain II of the site 4 in the inward, closed configuration3,4.
Target TTX-sensitive Na+ channels
Net Peptide Content: 100%
Last update: 11/03/2019
Huwentoxin-IV (#STH-100) is a highly pure, synthetic, and biologically active peptide toxin.
For research purposes only, not for human use