Skip to Content

Three-dimensional structure of I(to): Kv4.2-KChIP2 ion channels by electron microscopy at 21 Angstrom resolution

TitleThree-dimensional structure of I(to): Kv4.2-KChIP2 ion channels by electron microscopy at 21 Angstrom resolution
Publication TypeJournal Article
Year of Publication2004
AuthorsKim, LA, Furst J, Gutierrez D, Butler MH, Xu S, Goldstein SA, Grigorieff N
Refereed DesignationRefereed
JournalNeuron
Volume41
Pagination513-9
Date PublishedFeb 19
ISBN Number0896-6273 (Print)
Accession Number14980201
Keywords*Potassium Channels, Voltage-Gated, Animals, Calcium-Binding Proteins/chemistry/metabolism/*ultrastructure, Cell Membrane/metabolism/*ultrastructure, COS Cells, Humans, Image Processing, Computer-Assisted, Kv Channel-Interacting Proteins, Membrane Potentials/physiology, Microscopy, Electron, Molecular Structure, Potassium Channels/chemistry/metabolism/*ultrastructure, Protein Structure, Tertiary/physiology, Shal Potassium Channels
Abstract

Regulatory KChIP2 subunits assemble with pore-forming Kv4.2 subunits in 4:4 complexes to produce native voltage-gated potassium (Kv) channels like cardiac I(to) and neuronal I(A) subtypes. Here, negative stain electron microscopy (EM) and single particle averaging reveal KChIP2 to create a novel approximately 35 x 115 x 115 Angstrom, intracellular fenestrated rotunda: four peripheral columns that extend down from the membrane-embedded portion of the channel to enclose the Kv4.2 "hanging gondola" (a platform held beneath the transmembrane conduction pore by four internal columns). To reach the pore from the cytosol, ions traverse one of four external fenestrae to enter the rotundal vestibule and then cross one of four internal windows in the gondola.

URLhttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=14980201
PreviewAttachmentSize
Kim_Neuron2004.pdf322.48 KB