title: Atomic structure of a voltage-dependent K+ channel in a lipid membrane-like environment.
abstract: Voltage-dependent K+ (Kv) channels repolarize the action potential in neurons and muscle. This type of channel is gated directly by membrane voltage through protein domains known as voltage sensors, which are molecular voltmeters that read the membrane voltage and regulate the pore. Here we describe the structure of a chimaeric voltage-dependent K+ channel, which we call the 'paddle-chimaera channel', in which the voltage-sensor paddle has been transferred from Kv2.1 to Kv1.2. Crystallized in complex with lipids, the complete structure at 2.4 ångström resolution reveals the pore and voltage sensors embedded in a membrane-like arrangement of lipid molecules. The detailed structure, which can be compared directly to a large body of functional data, explains charge stabilization within the membrane and suggests a mechanism for voltage-sensor movements and pore gating.
authors.affiliation: Howard Hughes Medical Institute, Laboratory of Molecular Neurobiology and Biophysics, Rockefeller University, 1230 York Avenue, New York, New York 10065, USA.
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Long
authors.forename: Xiao
authors.initials: X
authors.lastname: Tao
authors.forename: Ernest B
authors.initials: EB
authors.lastname: Campbell
authors.forename: Roderick
authors.initials: R
authors.lastname: MacKinnon
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D017124:Conserved Sequence; D003460:Crystallization; D015640:Ion Channel Gating; D051663:Kv1.2 Potassium Channel / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008055:Lipids / Q000032:analysis; D008563:Membrane Lipids / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010843:Pichia; D011487:Protein Conformation; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D051669:Shab Potassium Channels / Q000737:chemistry* / Q000235:genetics
chemical_list: C496991:Kcnb1 protein, rat; D051663:Kv1.2 Potassium Channel; D008055:Lipids; D008563:Membrane Lipids; D011993:Recombinant Fusion Proteins; D051669:Shab Potassium Channels