Overview
- Holford, M. et al. (2009) Toxicon 53, 90.
Alomone Labs µ-Conotoxin-BuIIIA blocks NaV1.4 channel current expressed in Xenopus oocytes.A. Time course of µ-Conotoxin-BuIIIA (#STC-540) inhibition of NaV1.4 channel currents. Membrane potential was held at -100 mV and current was elicited by a 120 ms voltage step to 0 mV, delivered every 10 sec. 100 nM BuIIIA, applied for 8 min, as indicated by the bar (green), significantly inhibited the current. B. Superimposed traces of NaV1.4 currents upon application of control (black) and of 100 nM BuIIIA (green), taken from the recording shown in A.
μ-Conotoxins (μ-CTX) are peptide toxins that block voltage-gated Na+ channels (VGSCs), which are responsible for the influx of Na+ ions during action potentials in excitable tissues1.
µ-Conotoxin BuIIIA is originally isolated from the venom of the cone snail Conus bullatus and acts as a selective and potent blocker of voltage-gated NaV1.2 and NaV1.4 channels. The conotoxin inhibits Na+ flux by blocking the Na+ channel pore.
BuIIIA is considered to be part of a novel class of μ-conopeptides discovered from a newly defined class of fish-hunting cone snails, the Textilia clade. In addition, Conus bullatus peptides help define a new branch of the M-superfamily of conotoxins, namely M-5 due to a unique N-terminal extension. This N-terminus also exists in µ-Conotoxin BuIIIB and BuIIIC but absent in all other μ-conotoxins2,3.
µ-Conotoxin BuIIIA is used to determine the structure-activity relationship of voltage-gated Na+ channels3.
