Overview
- Olivera, B.M. et al. (1990) Science 249, 257.
- Sato, K. et al. (1991) J. Biol. Chem. 266, 16989.
Alomone Labs µ-Conotoxin GIIIA blocks NaV1.4 currents in Xenopus oocytes.A. Time course of µ-Conotoxin GIIIA (#STC-280) action on maximum NaV1.4 current amplitude. Maximum peak current amplitudes were plotted as a function of time. Membrane potential was held at -100 mV and oocytes were stimulated by a 100 ms voltage step to 0 mV. 100 nM µ-Conotoxin-GIIIA was perfused as indicated by the bar (green) for 5 min. B. Superimposed examples of NaV1.4 channel peak current in the absence (control) and presence (green) of 100 nM µ-Conotoxin-GIIIA (taken from the experiment in A).
μ-Conotoxin GIIIA is a peptide toxin originally isolated from the venom of Conus geographus. It specifically blocks skeletal muscle Na+ channels (NaV1.4) with an IC50 of 1500 nM1.
NaV channels are targets for many toxins, which bind with high affinity to various sites on the channel protein, µ-Conotoxin selectively binds to the NaV1.4 channel, blocks the pore and disabling its normal function, act as an antagonist for VGSCs1.
Voltage-gated NaV channels (VGSCs) play a key role in the electric excitability of cells by regulating the influx of sodium ions. VGSCs are responsible for initiating and propagating action potentials, which are essential for the activity of a wide selection of cells and tissues such as neurons, heart and muscle. In mammals, nine different subtypes (NaV1.1-1.9) have been identified, each with distinct distribution.
VGSCs acts as a potential drug targets for related disorders such as cardiac and neuropathic diseases2,3.
