Functional analysis of a de novo GRIN2A missense mutation associated with early-onset epileptic encephalopathy.
Nat Commun
; 5: 3251, 2014.
Article
em En
| MEDLINE
| ID: mdl-24504326
ABSTRACT
NMDA receptors (NMDARs), ligand-gated ion channels, play important roles in various neurological disorders, including epilepsy. Here we show the functional analysis of a de novo missense mutation (L812M) in a gene encoding NMDAR subunit GluN2A (GRIN2A). The mutation, identified in a patient with early-onset epileptic encephalopathy and profound developmental delay, is located in the linker region between the ligand-binding and transmembrane domains. Electrophysiological recordings revealed that the mutation enhances agonist potency, decreases sensitivity to negative modulators including magnesium, protons and zinc, prolongs the synaptic response time course and increases single-channel open probability. The functional changes of this amino acid apply to all other NMDAR subunits, suggesting an important role of this residue on the function of NMDARs. Taken together, these data suggest that the L812M mutation causes overactivation of NMDARs and drives neuronal hyperexcitability. We hypothesize that this mechanism underlies the patient's epileptic phenotype as well as cerebral atrophy.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Espasmos Infantis
/
Receptores de N-Metil-D-Aspartato
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Limite:
Child
/
Humans
/
Infant
/
Male
Idioma:
En
Revista:
Nat Commun
Assunto da revista:
BIOLOGIA
/
CIENCIA
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Estados Unidos