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Updated: Jul 23, 2026

Mutagenesis and Functional Analysis of Ion Channels Heterologously Expressed in Mammalian Cells
Published on: October 1, 2010
Structural conservation in prokaryotic and eukaryotic potassium channels
R MacKinnon1, S L Cohen, A Kuo
1Laboratory of Molecular Neurobiology and Biophysics and the Howard Hughes Medical Institute, Rockefeller University, 1230 York Avenue, New York, NY 10021, USA. mackinn@rockvax.rockefeller.edu
Abstract:
Toxins from scorpion venom interact with potassium channels. Resin-attached, mutant K+ channels from Streptomyces lividans were used to screen venom from Leiurus quinquestriatus hebraeus, and the toxins that interacted with the channel were rapidly identified by mass spectrometry. One of the toxins, agitoxin2, was further studied by mutagenesis and radioligand binding. The results show that a prokaryotic K+ channel has the same pore structure as eukaryotic K+ channels. This structural conservation, through application of techniques presented here, offers a new approach for K+ channel pharmacology.
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