%0 Journal Article
%T Effects of Arg20 Mutation on Sodium Channels Activity of JZTX-V<br>Arg20突变对敬钊缨毛蛛毒素-V钠通道活性的影响
%A Xiongzhi Zeng
%A Meichun Deng
%A Jianhui Pi
%A Miaohua Quan
%A Xianchun Wang
%A Songping Liang
%A <br>曾雄智
%A 邓梅春
%A 皮建辉
%A 全妙华
%A 王贤纯
%A 梁宋平
%J 生物工程学报
%D 2008
%I 
%X Jingzhaotoxin-V(JZTX-V) isolated from the venom of the spider Chilobrachys jingzhao is a novel potent inhibitor that acts on tetrodotoxin-resistant and tetrodotoxin-sensitive sodium channels in adult rat dorsal root ganglion(DRG) neurons. It is a 29-residue polypeptide toxin including three disulfide bridges. To investigate the structure-function relationship of the toxin, a mutant of JZTX-V in which Arg20 was substituted by Ala, was synthesized by solid-phase chemistry method with Fmoc-protected amino acids on the PS3 automated peptide synthesizer. The synthetic linear peptide was then purified by reversed-phase high performance liquid chromatography and oxidatively refolded under the optimal conditions. The refolded product was analyzed by matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry(MALDI-TOF MS) and electrophysiological experiments for its relative molecular weight and prohibitive activity of sodium channels respectively. The present findings show that the prohibitive effect of R20A-JZTX-V on TTX-S sodium channels in DRG neurons is almost the same as that of native JZTX-V, suggesting that Arg20 does not play any important role in inhibiting TTX-S sodium currents in DRG neurons. In contrast, the prohibitive level of R20A-JZTX-V on TTX-R sodium channels is reduced by at last 18.3 times, indicating that Arg20 is a key amino acid residue relative to the bioactivity of JZTX-V. It is presumed that the decrease in activity of R20A-JZTX-V is due to the changes of the property in the binding site in TTX-R sodium channels.
%K JZTX-V
%K solid-phase synthesis
%K mutant
%K oxidative refolding
%K patch-clamp<br>敬钊缨毛蛛毒素-V
%K 固相多肽合成
%K 突变体
%K 氧化复性
%K 膜片钳
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=A66E90C274451689E69F6F0291467824&aid=3B4B3E14348D6CED20AC9A19A600F547&yid=67289AFF6305E306&vid=B91E8C6D6FE990DB&iid=DF92D298D3FF1E6E&sid=323ACE6C9CE37BAB&eid=880C4253794026AD&journal_id=1000-3061&journal_name=生物工程学报&referenced_num=0&reference_num=9