Identification of the cysteine residue responsible for disulfide linkage of Na+ channel α and β2 subunits.

ABSTRACT: Voltage-gated Na(+) channels in the brain are composed of a single pore-forming α subunit, one non-covalently linked β subunit (β1 or β3), and one disulfide-linked β subunit (β2 or β4). The final step in Na(+) channel biosynthesis in central neurons is concomitant α-β2 disulfide linkage and insertion into the plasma membrane. Consistent with this, Scn2b (encoding β2) null mice have reduced Na(+) channel cell surface expression in neurons, and action potential conduction is compromised. Here we generated a series of mutant β2 cDNA constructs to investigate the cysteine residue(s) responsible for α-β2 subunit covalent linkage. We demonstrate that a single cysteine-to-alanine substitution at extracellular residue Cys-26, located within the immunoglobulin (Ig) domain, abolishes the covalent li

SUBMITTER: Chen C 

PROVIDER: S-EPMC3493947 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature