Functional analysis of the alpha-neurotoxin, BmalphaTX14, derived from the Chinese scorpion, Buthus martensii Karsch.
The gene encoding the BmalphaTX14 (alpha-neurotoxin TX14) protein, derived from the cDNA library of the Chinese scorpion Buthus martensii Karsch, was expressed in Pichia pastoris. The recombinant protein was purified by metal chelate affinity chromatography and gel filtration chromatography. Using patch-clamp technique, electrophysiological activity of rBmalphaTX14 was identified. In the neurons isolated from mice trigeminal root ganglion, the Na+ current amplitude was reduced by 80% under whole cell patch-clamp recording. There were no apparent modifications to the gating mechanism in the presence of rBmalphaTX14. Although BmalphaTX14 shared a high amino acid sequence similarity with other typical alpha-toxins, it has different effects on neurons. Further electrophysiological analysis suggested that rBmalphaTX14 selectively blocked Na+ channels and is a member of a new group of scorpion toxins.
Wang
Kun
K
State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, Hubei 430072, P.R. China.
Yin
Shi-Jin
SJ
Lu
Meng
M
Yi
Hong
H
Dai
Chao
C
Xu
Xiu-Jing
XJ
Cao
Zhi-Jian
ZJ
Wu
Ying-Liang
YL
Li
Wen-Xin
WX
D000818:Animals; D018244:Chromosomes, Artificial, Yeast; D015723:Gene Library; D051379:Mice; D008969:Molecular Sequence Data; D009498:Neurotoxins / Q000096:biosynthesis / Q000302:isolation & purification / Q000494:pharmacology*; D018408:Patch-Clamp Techniques; D010843:Pichia / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000302:isolation & purification* / Q000494:pharmacology; D012604:Scorpion Venoms / Q000737:chemistry*; D012605:Scorpions; D017386:Sequence Homology, Amino Acid; D026941:Sodium Channel Blockers / Q000302:isolation & purification* / Q000494:pharmacology; D015222:Sodium Channels / Q000187:drug effects*; D012668:Trigeminal Ganglion / Q000187:drug effects*
D009498:Neurotoxins; D011994:Recombinant Proteins; D012604:Scorpion Venoms; D026941:Sodium Channel Blockers; D015222:Sodium Channels; C518690:alpha-neurotoxin TX14, Buthus martensii