Structure of the voltage-gated K⺠channel Eag1 reveals an alternative voltage sensing mechanism.
Science
; 353(6300): 664-9, 2016 Aug 12.
Article
em En
| MEDLINE
| ID: mdl-27516594
ABSTRACT
Voltage-gated potassium (K(v)) channels are gated by the movement of the transmembrane voltage sensor, which is coupled, through the helical S4-S5 linker, to the potassium pore. We determined the single-particle cryo-electron microscopy structure of mammalian K(v)10.1, or Eag1, bound to the channel inhibitor calmodulin, at 3.78 angstrom resolution. Unlike previous K(v) structures, the S4-S5 linker of Eag1 is a five-residue loop and the transmembrane segments are not domain swapped, which suggest an alternative mechanism of voltage-dependent gating. Additionally, the structure and position of the S4-S5 linker allow calmodulin to bind to the intracellular domains and to close the potassium pore, independent of voltage-sensor position. The structure reveals an alternative gating mechanism for K(v) channels and provides a template to further understand the gating properties of Eag1 and related channels.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ativação do Canal Iônico
/
Canais de Potássio Éter-A-Go-Go
Limite:
Animals
Idioma:
En
Revista:
Science
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Estados Unidos