摘　要：Nav1.7特异性地表达在外周伤害性感觉神经元。临床遗传学、动物模型和药理学研究表明，Nav1.7是一个重要的镇痛药物开发靶点。本研究以沟纹硬皮地蛛（Calommata signata Karsch）毒液为研究对象，通过电刺激采集毒液、反相高效液相色谱分离纯化、质谱鉴定、蛋白质测序以及全细胞膜片钳记录等方法，筛选并鉴定到一种对Nav1.7有抑制作用的新型多肽毒素，命名为APTX-1。质谱鉴定该多肽毒素的分子质量为7 815.2 Da；其N端前10位氨基酸序列为ASCKQVGEEC。APTX-1抑制Nav1.7电流具有浓度依赖性，其半数抑制浓度为（0.46±0.08） μmol/L。通道动力学分析显示，APTX-1并不影响Nav1.7的翻转电位、电压依赖性稳态激活曲线和失活曲线，表明该多肽毒素并不影响Nav1.7的离子选择性和电压依赖性。综上所述，本研究获得了一个新型Nav1.7调制剂，并探究了其对Nav1.7的作用特点，为靶向Nav1.7的镇痛药物研发提供了潜在先导分子。
关键词：沟纹硬皮地蛛；多肽毒素；Nav1.7；APTX-1；疼痛
中图分类号：O629.72                        文献标志码：A                       DOI：10.3969/j.issn.1007-7146.2023.02.005

Abstract: Voltage-gated sodium channel Nav1.7 is preferentially expressed in peripheral nociceptors. Clinical genetics，animal models and pharmacological studies indicate that Nav1.7 is an important target for analgesic drug development. In this paper，we report the isolation and characterization of APTX-1，a novel peptide toxin from the venom of spider Calommata signata Karsch. Patch-clamp analysis confirmed that APTX-1 potently inhibits the currents of Nav1.7. Mass spectrum results showed that the molecular weight of APTX-1 was 7 815.2 Da. The first 10 amino acid positions at the N terminal were ASCKQVGEEC. APTX-1 inhibited Nav1.7 currents in a concentration-dependent manner，with a half-inhibitory concentration of (0.46±0.08) μmol/L. Channel dynamics analysis showed that APTX-1 did not affect the reversal potential，voltage-dependent steady-state activation curve，and inactivation curve of Nav1.7，indicating that the peptide toxin did not affect the ion selectivity and voltage dependence of Nav1.7. In conclusion，we found a novel Nav1.7 peptide inhibitor，and the characteristics of its action on Nav1.7 were studied to provide lead molecules for the development of analgesic drugs targeting the Nav1.7.
Key words: Calommata signata Karsch; peptide toxin; Nav1.7; APTX-1; pain
（Acta Laser Biology Sinica, 2023, 32(2): 139-145）