PDBsum entry 5a6f

Transport

PDB id: 5a6f

Contents

Protein chains

540 a.a.

43 a.a.

PDB id:

5a6f

Name:

Transport

Title:

Cryo-em structure of the slo2.2 na-activated k channel

Structure:

Gating ring of potassium channel subfamily t member 1. Chain: c. Synonym: sequence like a calcium-activated potassium channel subunit, slo2.2. Engineered: yes. Rck2 elaboration of potassium channel subfamily t member 1. Chain: d. Synonym: sequence like a calcium-activated potassium channel subunit, slo2.2.

Source:

Gallus gallus. Chicken. Organism_taxid: 9031. Expressed in: spodoptera frugiperda. Expression_system_taxid: 7108.

Authors:

R.K.Hite,P.Yuan,Z.Li,Y.Hsuing,T.Walz,R.Mackinnon

Key ref:

R.K.Hite et al. (2015). Cryo-electron microscopy structure of the Slo2.2 Na(+)-activated K(+) channel. Nature, 527, 198-203. PubMed id: 26436452 DOI: 10.1038/nature14958

Date:

25-Jun-15 Release date: 14-Oct-15

Protein chain

Q8QFV0  (KCNT1_CHICK) -  Potassium channel subfamily T member 1 from Gallus gallus

Seq: 1201 a.a.

Struc: 540 a.a.*

Protein chain

No UniProt id for this chain

Struc: 43 a.a.

* PDB and UniProt seqs differ at 29 residue positions (black crosses)

DOI no: 10.1038/nature14958

Nature 527:198-203 (2015)

PubMed id: 26436452

Cryo-electron microscopy structure of the Slo2.2 Na(+)-activated K(+) channel.

R.K.Hite, P.Yuan, Z.Li, Y.Hsuing, T.Walz, R.MacKinnon.

ABSTRACT

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 ångströms. 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.