High-Resolution Cryoelectron Microscopy Structure of the Cyclic Nucleotide-Modulated Potassium Channel MloK1 in a Lipid Bilayer.
Structure
; 26(1): 20-27.e3, 2018 01 02.
Article
em En
| MEDLINE
| ID: mdl-29249605
ABSTRACT
Eukaryotic cyclic nucleotide-modulated channels perform their diverse physiological roles by opening and closing their pores to ions in response to cyclic nucleotide binding. We here present a structural model for the cyclic nucleotide-modulated potassium channel homolog from Mesorhizobium loti, MloK1, determined from 2D crystals in the presence of lipids. Even though crystals diffract electrons to only â¼10 Å, using cryoelectron microscopy (cryo-EM) and recently developed computational methods, we have determined a 3D map of full-length MloK1 in the presence of cyclic AMP (cAMP) at â¼4.5 Å isotropic 3D resolution. The structure provides a clear picture of the arrangement of the cyclic nucleotide-binding domains with respect to both the pore and the putative voltage sensor domains when cAMP is bound, and reveals a potential gating mechanism in the context of the lipid-embedded channel.
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Base de dados:
MEDLINE
Assunto principal:
Potássio
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Proteínas de Bactérias
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AMP Cíclico
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Canais de Potássio de Abertura Dependente da Tensão da Membrana
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Mesorhizobium
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Bicamadas Lipídicas
Idioma:
En
Revista:
Structure
Assunto da revista:
BIOLOGIA MOLECULAR
/
BIOQUIMICA
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BIOTECNOLOGIA
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
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