Novel effects of dendrotoxin homologues on subtypes of mammalian Kv1 potassium channels expressed in Xenopus oocytes

FEBS Letters

Butler, Carolynn⁴  Robertson, Brian²  Newland, Claire¹  Stow, John⁴  Owen, David³ 

[1] Neurosciences Group, Institute of Molecular Medicine, Oxford OX3 9DU, UK;Department of Biochemistry, Imperial College of Science, Technology and Medicine, London SW7 2AZ, UK;Electrophysiology Laboratory, Wyeth Research (U.K.) Ltd., Taplow, Maidenhead SL6 0PG, UK;Chemistry, Wyeth Research (U.K.) Ltd., Taplow, Maidenhead SL6 0PH, UK

关键词: Potassium channel;    Dendrotoxin;    Oocyte;    Toxin;    Ion channel;    Rat brain;   

DOI  :  10.1016/0014-5793(96)00211-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have examined the effects of two DTX homologues, toxin I and toxin K, on Kv1.1, Kv1.2 and Kv1.6 channels expressed in Xenopus oocytes. Toxin I blocked all three channels; in contrast, toxin K was selective for Kv1.1. Both toxins slowed channel activation and inactivation kinetics with 10 nM toxin I approximately doubling activation and inactivation time constants of Kv1.1. For the first time, we have demonstrated the selectivity of a DTX homologue for a single cloned Kv1 channel and suggest that these toxins may sterically hinder the conformational changes that occur during channel gating.

【 授权许可】

Unknown