Regulation of the NaV1.5 cytoplasmic domain by calmodulin.
Nat Commun
; 5: 5126, 2014 Nov 05.
Article
en En
| MEDLINE
| ID: mdl-25370050
ABSTRACT
Voltage-gated sodium channels (Na(v)) underlie the rapid upstroke of action potentials in excitable tissues. Binding of channel-interactive proteins is essential for controlling fast and long-term inactivation. In the structure of the complex of the carboxy-terminal portion of Na(v)1.5 (CTNa(v)1.5) with calmodulin (CaM)-Mg(2+) reported here, both CaM lobes interact with the CTNa(v)1.5. On the basis of the differences between this structure and that of an inactivated complex, we propose that the structure reported here represents a non-inactivated state of the CTNa(v), that is, the state that is poised for activation. Electrophysiological characterization of mutants further supports the importance of the interactions identified in the structure. Isothermal titration calorimetry experiments show that CaM binds to CTNa(v)1.5 with high affinity. The results of this study provide unique insights into the physiological activation and the pathophysiology of Na(v) channels.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Calmodulina
/
Citoplasma
/
Canal de Sodio Activado por Voltaje NAV1.5
Tipo de estudio:
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
Nat Commun
Asunto de la revista:
BIOLOGIA
/
CIENCIA
Año:
2014
Tipo del documento:
Article