Guangxitoxin 1E 

Guangxitoxin 1E is a potent and selective blocker of K_V2.1 and K_V2.2 channels. Guangxitoxin 1E inhibits K_V2 with an IC₅₀ of 1-3 nM. K_V2 channels underlie delayed-rectifier potassium currents in various neurons^[1][2].

IC50: 1-3 nM (K_V2 channels); 24-54 nM (K_V4.3 channels)^[2]

Guangxitoxin 1E inhibits K_V2 with an IC₅₀ of 1-3 nM but has no significant effect on K_V1.2, K_V1.3, K_V1.5, K_V3.2 and BK potassium channels, nor on calcium and sodium channels Ca_V1.2, Ca_V2.2, Na_V1.5, Na_V1.7, Na_V1.8, whereas the IC₅₀ for K_V4.3 channels is 24-54 nM^[2].
In mouse β-cells, Guangxitoxin 1E inhibits 90% of I_DR and, as for K_V2.1, shifts the voltage dependence of channel activation to more depolarized potentials, a characteristic of gating-modifier peptides. Guangxitoxin 1E broadens theβ-cell action potential, enhances glucose-stimulated intracellular calcium oscillations, and enhances insulin secretion from mouse pancreatic islets in a glucose-dependent manner^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

3948.61

C₁₇₈H₂₄₈N₄₄O₄₅S₇

1233152-82-3

Solid

White to off-white

Glu-Gly-Glu-Cys-Gly-Gly-Phe-Trp-Trp-Lys-Cys-Gly-Ser-Gly-Lys-Pro-Ala-Cys-Cys-Pro-Lys-Tyr-Val-Cys-Ser-Pro-Lys-Trp-Gly-Leu-Cys-Asn-Phe-Pro-Met-Pro (Disulfide bridge:Cys4-Cys19;Cys11-Cys24;Cys18-Cys31)

EGECGGFWWKCGSGKPACCPKYVCSPKWGLCNFPMP (Disulfide bridge:Cys4-Cys19;Cys11-Cys24;Cys18-Cys31)

Room temperature in continental US; may vary elsewhere.

Sealed storage, away from moisture

*In solvent : -80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture)

• [1]. Hönigsperger C, et al. Physiological roles of Kv2 channels in entorhinal cortex layer II stellate cells revealed by Guangxitoxin-1E. J Physiol. 2017 Feb 1;595(3):739-757.  [Content Brief]

  [2]. Herrington J, et al. Blockers of the delayed-rectifier potassium current in pancreatic beta-cells enhance glucose-dependent insulin secretion. Diabetes. 2006 Apr;55(4):1034-42.  [Content Brief]