Guangxitoxin 1E

Guangxitoxin 1E
Selective blocker of K_v2.1 and K_v2.2

Guangxitoxin-1E (GxTx-1E) was isolated from the venom of Chilobrachys jingzhao (Chinese earth tiger tarantula).Guangxitoxin-1E was shown to block K_v2.1/KCNB1, K_v2.2/KCNB2 and K_v4.3/KCND3 channels without significant effect on K_v1.2/KCNA2, K_v1.3/KCNA3, K_v1.5/KCNA5, K_v3.2/KCNC2, Ca_v1.2/CACNA1C, Ca_v2.2/CACNA1B, Na_v1.5/SCN5A, Na_v1.7/SCN9A or Na_v1.8/SCN10A channels. Guangxitoxin-1E inhibits K_v2.1 with an IC₅₀ value of 1 nM and K_v2.2 with an IC₅₀ value of 3 nM. Block of K_v4.3 occurs at 10-20 fold higher concentrations. Guangxitoxin-1E acts as a gating modifier since it shifts the voltage-dependence of K_v2.1 K⁺ currents towards depolarized potentials. In pancreatic beta-cells, Guangxitoxin-1E enhances glucose-stimulated insulin secretion by broadening the cell action potential and enhancing calcium oscillations.

Therapeutic area

Diabetes type 2

Guangxitoxin-1E technical information

AA sequence: Glu-Gly-Glu-Cys⁴-Gly-Gly-Phe-Trp-Trp-Lys-Cys¹¹-Gly-Ser-Gly-Lys-Pro-Ala-Cys¹⁸-Cys¹⁹-Pro-Lys-Tyr-Val-Cys²⁴-Ser-Pro-Lys-Trp-Gly-Leu-Cys³¹-Asn-Phe-Pro-Met-Pro-OH
Presumed disulfide bridge pattern: Cys⁴-Cys¹⁹, Cys¹¹-Cys²⁴ and Cys¹⁸-Cys³¹
Length (aa): 36
Formula: C₁₇₈H₂₄₈N₄₄O₄₅S₇
Molecular Weight: 3948.70 Da
Appearance: White lyophilized solid
Solubility: water and saline buffer
CAS number: not available
Source: Synthetic
Purity rate: > 95%

11GUA002-00050	GxTx-1E	0.05mg
11GUA002-50050	GxTx-1E	5 x 0.05mg
1GUA002-00100	GxTx-1E	0.1mg
11GUA002-00500	GxTx-1E	0.5mg