title: Characterization of ion channels on subesophageal ganglion neurons from Chinese tarantula Ornithoctonus huwena: Exploring the myth of the spider insensitive to its venom.
abstract: Chinese tarantula Ornithoctonus huwena is one of the most venomous spiders distributing in the hilly areas of southern China. In this study, using whole-cell patch-clamp technique we investigated electrophysiological and pharmacological properties of ion channels from tarantula subesophageal ganglion neurons. It was found that the neurons express multiple kinds of ion channels at least including voltage-gated calcium channels, TTX-sensitive sodium channels and two types of potassium channels. They exhibit pharmacological properties similar to mammalian subtypes. Spider calcium channels were sensitive to ω-conotoxin GVIA and diltiazem, two well-known inhibitors of mammalian neuronal high-voltage-activated (HVA) subtypes. 4-Aminopyridine and tetraethylammonium could inhibit spider outward transient and delayed-rectifier potassium channels, respectively. Huwentoxin-I and huwentoxin-IV are two abundant toxic components in the venom of Ornithoctonus huwena. Interestingly, although in our previous work they inhibit HVA calcium channels and TTX-sensitive sodium channels from mammalian sensory neurons, respectively, they fail to affect the subtypes from spider neurons. Moreover, the crude venom has no effect on delayed-rectifier potassium channels and only slightly reduces transient outward potassium channels with an IC50 value of ∼51.3 mg/L. Therefore, our findings provide important evidence for ion channels from spiders having an evolution as self-defense and prey mechanism.
authors.affiliation: State Key Laboratory of Medical Genetics and School of Life Sciences, Central South University, Changsha, Hunan, 410013, China; Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, Hunan, 410081, China. Electronic address: dengmch@csu.edu.cn.
authors.forename: Meichun
authors.initials: M
authors.lastname: Deng
authors.affiliation: Key Laboratory of Research and Utilization of Ethnomedicinal Plant Resources of Hunan Province, School of Biological and Food Engineering, Huaihua College, Huaihua, Hunan, 418008, China; Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, Hunan, 410081, China. Electronic address: huzhaotun@163.com.
authors.forename: Zhaotun
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, Hunan, 410081, China.
authors.forename: Tianfu
authors.initials: T
authors.lastname: Cai
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, Hunan, 410081, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Medical Genetics and School of Life Sciences, Central South University, Changsha, Hunan, 410013, China.
authors.forename: Wenfang
authors.initials: W
authors.lastname: Wu
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, Hunan, 410081, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Luo
authors.affiliation: Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha, Hunan, 410013, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, Hunan, 410081, China.
authors.forename: Meichi
authors.initials: M
authors.lastname: Wang
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, Hunan, 410081, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, Hunan, 410081, China.
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, Hunan, 410081, China. Electronic address: liangsp@hunnu.edu.cn.
authors.forename: Songping
authors.initials: S
authors.lastname: Liang
mesh_terms: D000818:Animals; D004947:Esophagus / Q000166:cytology / Q000187:drug effects*; D005260:Female; D005724:Ganglia / Q000166:cytology / Q000187:drug effects*; D015640:Ion Channel Gating; D007473:Ion Channels / Q000502:physiology*; D009474:Neurons / Q000187:drug effects*; D013111:Spider Venoms / Q000633:toxicity*; D013112:Spiders / Q000187:drug effects*
chemical_list: D007473:Ion Channels; D013111:Spider Venoms
keywords: Adaptive insensitivity; Calcium channel; Chinese tarantula; Potassium channel; Sodium channel; Toxin; Whole-cell