Molecular mechanisms underlying membrane-potential-mediated regulation of neuronal K2P2.1 channels.
Mol Cell Neurosci
; 43(1): 117-26, 2010 Jan.
Article
em En
| MEDLINE
| ID: mdl-19837167
ABSTRACT
The activity of background K(2P) channels adjusts the resting membrane potential to enable plasticity of excitable cells. Here we have studied the regulation of neuronal K(2P)2.1 (KCNK2, TREK-1) channel activity by resting membrane potential. When heterologously expressed, K(2P)2.1 currents gradually increased at hyperpolarizing potentials and declined at depolarizing potentials, with a midpoint potential of -60 mV. As K(2P) channels are not equipped with an integral voltage sensor, we sought extrinsic cellular components that could convert changes in the membrane electrical field to cellular activity that would indirectly modify K(2P)2.1 currents. We propose that membrane depolarization activated the Gq protein-coupled receptor pathway, in the apparent absence of ligand, resulting in phosphatidylinositol-4,5-bisphosphate (PIP(2)) depletion through the action of phospholipase C. Our results suggest a novel mechanism in which an indirect pathway confers membrane potential regulation onto channels that are not intrinsically voltage sensitive to enhance regulation of neuronal excitability levels.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Canais de Potássio de Domínios Poros em Tandem
/
Potenciais da Membrana
/
Neurônios
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Mol Cell Neurosci
Assunto da revista:
BIOLOGIA MOLECULAR
/
NEUROLOGIA
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Israel