IBMM, CNRS, ENSCM, Université de Montpellier, France.
Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA.
FEBS J. 2023 Jul;290(14):3688-3702. doi: 10.1111/febs.16773. Epub 2023 Mar 23.
Venom-derived peptides targeting ion channels involved in pain are regarded as a promising alternative to current, and often ineffective, chronic pain treatments. Many peptide toxins are known to specifically and potently block established therapeutic targets, among which the voltage-gated sodium and calcium channels are major contributors. Here, we report on the discovery and characterization of a novel spider toxin isolated from the crude venom of Pterinochilus murinus that shows inhibitory activity at both hNa 1.7 and hCa 3.2 channels, two therapeutic targets implicated in pain pathways. Bioassay-guided HPLC fractionation revealed a 36-amino acid peptide with three disulfide bridges named μ/ω-theraphotoxin-Pmu1a (Pmu1a). Following isolation and characterization, the toxin was chemically synthesized and its biological activity was further assessed using electrophysiology, revealing Pmu1a to be a toxin that potently blocks both hNa 1.7 and hCa 3. Nuclear magnetic resonance structure determination of Pmu1a shows an inhibitor cystine knot fold that is the characteristic of many spider peptides. Combined, these data show the potential of Pmu1a as a basis for the design of compounds with dual activity at the therapeutically relevant hCa 3.2 and hNa 1.7 voltage-gated channels.
靶向参与疼痛的离子通道的毒液衍生肽被认为是当前（通常无效的）慢性疼痛治疗的一种有前途的替代方法。许多肽毒素被认为能够特异性和有效地阻断既定的治疗靶点，其中电压门控钠和钙通道是主要贡献者。在这里，我们报告了一种从 Pterinochilus murinus 粗毒液中分离得到的新型蜘蛛毒素的发现和特性，该毒素对 hNa 1.7 和 hCa 3.2 通道均具有抑制活性，这两个治疗靶点都与疼痛途径有关。基于生物测定的 HPLC 分步分离揭示了一种具有三个二硫键的 36 个氨基酸肽，命名为 μ/ω-theraphotoxin-Pmu1a（Pmu1a）。在分离和表征后，该毒素被化学合成，并进一步使用电生理学评估其生物学活性，结果表明 Pmu1a 能够强烈阻断 hNa 1.7 和 hCa 3. Pmu1a 的核磁共振结构测定显示出一种抑制剂半胱氨酸结折叠，这是许多蜘蛛肽的特征。综合这些数据表明，Pmu1a 有潜力作为设计具有双重活性的化合物的基础，这些化合物在治疗相关的 hCa 3.2 和 hNa 1.7 电压门控通道上具有双重活性。
