Hainantoxin-III（海南捕鳥蛛毒素 III） 

Selective blocker of TTX-S VGSC(電壓門控鈉離子通道TTX-S選擇性阻斷劑)

Hainantoxin-III (HNTX-III) is a peptide that has been isolated from the venom of the Chinese bird spider Seleconosmia hainana.  Hainantoxin-III specifically blocks mammalian neuronal tetrodotoxin-sensitive voltage-gated sodium channels (VGSCs). Hainantoxin III was found inactive on tetrodotoxin-resistant VGSCs and voltage-gated Ca²⁺channels (both high and low voltage-activated). 

Hainantoxin-III strongly depressed the amplitude of rat DRG tetrodotoxin-sensitive Na⁺ currents with an IC₅₀ value of 1.1 nM. Like  Hainantoxin-IV, Hainantoxin-III causes a hyperpolarizing shift of about 10 mV in the voltage midpoint of steady-state Na⁺ channel inactivation. Similar to  Huwentoxin-IV, Hainantoxin-III and  Hainantoxin-IV do not affect the activation and inactivation kinetics of Na⁺ currents. 

Hainantoxin-III inhibits Na_v1.7 current amplitude without significantly altering the activation and inactivation kinetics.Hainantoxin-III increases the deactivation of the Na_v1.7 current after extreme depolarizations. Hainantoxin-III seems to interact with site 4 and to trap the domain II voltage sensor in the closed state. The inhibition of Na_v1.7 by hainantoxin-III is reversible upon washing, but no reversibility was observed for  Hainantoxin-IV and  Huwentoxin-IV. 

Hainantoxin-III was shown to block Na_v1.1, Na_v1.2, Na_v1.3 and Na_v1.7 expressed in HEK293 cells with IC₅₀ values of 1.27 µM, 275 nM, 491 nM and 232 nM, respectively.

Hainantoxin-III 技術資料

氨基酸序列：

Gly-Cys²-Lys-Gly-Phe-Gly-Asp-Ser-Cys⁹-Thr-Pro-Gly-Lys-Asn-Glu-Cys¹⁶-Cys¹⁷-Pro-Asn-Tyr-Ala-Cys²²-Ser-Ser-Lys-His-Lys-Trp-Cys²⁹-Lys-Val-Tyr-Leu-NH₂ 

二硫鍵：Cys²-Cys¹⁷, Cys⁹-Cys²², and Cys¹⁶-Cys²⁹ 

長度 (aa)： 33 

分子式： C₁₅₄H₂₂₈N₄₄O₄₅S₆  

分子量：3608.20 Da  

外觀： White lyophilized solid 

可溶性：water and saline buffer 

CAS 號：Not available 

來源：Synthetic  

純度： > 97%

產品信息