6EBM

The voltage-activated Kv1.2-2.1 paddle chimera channel in lipid nanodiscs, transmembrane domain of subunit alpha

Summary for 6EBM

• Entry DOI: 10.2210/pdb6ebm/pdb
• EMDB information: 9024 9025 9026
• Descriptor: Potassium voltage-gated channel subfamily A member 2,Potassium voltage-gated channel subfamily B member 2 chimera (1 entity in total)
• Functional Keywords: membrane protein, transport protein, potassium channel, lipid nanodisc
• Biological source: Rattus norvegicus (Rat); More
• Total number of polymer chains: 4
• Total formula weight: 235623.31

Authors

Matthies, D.,Bae, C.,Fox, T.,Bartesaghi, A.,Subramaniam, S.,Swartz, K.J. (deposition date: 2018-08-06, release date: 2018-08-22, Last modification date: 2024-03-13)

Primary citation

Matthies, D.,Bae, C.,Toombes, G.E.,Fox, T.,Bartesaghi, A.,Subramaniam, S.,Swartz, K.J.
Single-particle cryo-EM structure of a voltage-activated potassium channel in lipid nanodiscs.
Elife, 7:-, 2018

PubMed Abstract: Voltage-activated potassium (Kv) channels open to conduct K ions in response to membrane depolarization, and subsequently enter non-conducting states through distinct mechanisms of inactivation. X-ray structures of detergent-solubilized Kv channels appear to have captured an open state even though a non-conducting C-type inactivated state would predominate in membranes in the absence of a transmembrane voltage. However, structures for a voltage-activated ion channel in a lipid bilayer environment have not yet been reported. Here we report the structure of the Kv1.2-2.1 paddle chimera channel reconstituted into lipid nanodiscs using single-particle cryo-electron microscopy. At a resolution of ~3 Å for the cytosolic domain and ~4 Å for the transmembrane domain, the structure determined in nanodiscs is similar to the previously determined X-ray structure. Our findings show that large differences in structure between detergent and lipid bilayer environments are unlikely, and enable us to propose possible structural mechanisms for C-type inactivation.

PubMed: 30109985
DOI: 10.7554/eLife.37558

Experimental method

ELECTRON MICROSCOPY (4 Å)