5a6f

Cryo-EM structure of the Slo2.2 Na-activated K channelCryo-EM structure of the Slo2.2 Na-activated K channel

5a6f, resolution 4.20Å Show:Asymmetric Unit Biological Assembly Structural highlights 5a6f is a 2 chain structure with sequence from Chick. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Related: 5a6e, 5a6g Experimental data: Check Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function [KCNT1_CHICK] Generates outwardly rectifying currents that are suppressed by elevation of intracellular calcium. Publication Abstract from PubMed Na+-activated K+ channels are members of the Slo family of large conductance K+ channels that are widely expressed in the brain, where their opening regulates neuronal excitability. These channels fulfil a number of biological roles and have intriguing biophysical properties, including conductance levels that are ten times those of most other K+ channels and gating sensitivity to intracellular Na+. Here we present the structure of a complete Na+-activated K+ channel, chicken Slo2.2, in the Na+-free state, determined by cryo-electron microscopy at a nominal resolution of 4.5 angstroms. The channel is composed of a large cytoplasmic gating ring, in which resides the Na+-binding site and a transmembrane domain that closely resembles voltage-gated K+ channels. In the structure, the cytoplasmic domain adopts a closed conformation and the ion conduction pore is also closed. The structure reveals features that can explain the unusually high conductance of Slo channels and how contraction of the cytoplasmic gating ring closes the pore. Cryo-electron microscopy structure of the Slo2.2 Na-activated K channel.,Hite RK, Yuan P, Li Z, Hsuing Y, Walz T, MacKinnon R Nature. 2015 Oct 5. doi: 10.1038/nature14958. PMID:26436452 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Potassium channel 3D structures