RIM1 confers sustained activity and neurotransmitter vesicle anchoring to presynaptic Ca2+ channels.
Nat Neurosci
; 10(6): 691-701, 2007 Jun.
Article
em En
| MEDLINE
| ID: mdl-17496890
ABSTRACT
The molecular organization of presynaptic active zones is important for the neurotransmitter release that is triggered by depolarization-induced Ca2+ influx. Here, we demonstrate a previously unknown interaction between two components of the presynaptic active zone, RIM1 and voltage-dependent Ca2+ channels (VDCCs), that controls neurotransmitter release in mammalian neurons. RIM1 associated with VDCC beta-subunits via its C terminus to markedly suppress voltage-dependent inactivation among different neuronal VDCCs. Consistently, in pheochromocytoma neuroendocrine PC12 cells, acetylcholine release was significantly potentiated by the full-length and C-terminal RIM1 constructs, but membrane docking of vesicles was enhanced only by the full-length RIM1. The beta construct beta-AID dominant negative, which disrupts the RIM1-beta association, accelerated the inactivation of native VDCC currents, suppressed vesicle docking and acetylcholine release in PC12 cells, and inhibited glutamate release in cultured cerebellar neurons. Thus, RIM1 association with beta in the presynaptic active zone supports release via two distinct mechanisms sustaining Ca2+ influx through inhibition of channel inactivation, and anchoring neurotransmitter-containing vesicles in the vicinity of VDCCs.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Vesículas Sinápticas
/
Terminações Pré-Sinápticas
/
Neurotransmissores
/
Proteínas de Ligação ao GTP
/
Canais de Ânion Dependentes de Voltagem
/
Proteínas do Tecido Nervoso
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2007
Tipo de documento:
Article