Referenced in: none

Automatically associated channels: Nav1.1

Title: Nav1.1 channels with mutations of severe myoclonic epilepsy in infancy display attenuated currents.

Authors: Takashi Sugawara, Yuji Tsurubuchi, Tateki Fujiwara, Emi Mazaki-Miyazaki, Keiichi Nagata, Mauricio Montal, Yushi Inoue, Kazuhiro Yamakawa

Journal, date & volume: Epilepsy Res., 2003 May , 54, 201-7

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/12837571

Abstract
Severe myoclonic epilepsy in infancy (SMEI) is characterized by intractable febrile and afebrile seizures, severe mental decline, and onset during the first year of life. Nonsense, frameshift, and missense mutations of SCN1A gene encoding the voltage-gated Na(+) channel alpha-subunit type I (Na(v)1.1) have been identified in patients with SMEI. Here, we performed whole-cell patch-clamp analyses on HEK293 cells expressing human Na(v)1.1 channels bearing SMEI nonsense and missense mutations. The mutant channels showed remarkably attenuated or barely detectable inward sodium currents. Our findings indicate that SMEI mutations lead to loss-of-function and may contribute to the development of SMEI phenotypes.