The sodium channel {beta}3-subunit induces multiphasic gating in NaV1.3 and affects fast inactivation via distinct intracellular regions.

ABSTRACT: Electrical excitability in neurons depends on the activity of membrane-bound voltage gated sodium channels (Na(v)) that are assembled from an ion conducting α-subunit and often auxiliary β-subunits. The α-subunit isoform Na(v)1.3 occurs in peripheral neurons together with the Na(v) β3-subunit, both of which are coordinately up-regulated in rat dorsal root ganglion neurons after nerve injury. Here we examine the effect of the β3-subunit on the gating behavior of Na(v)1.3 using whole cell patch clamp electrophysiology in HEK-293 cells. We show that β3 depolarizes the voltage sensitivity of Na(v)1.3 activation and inactivation and induces biphasic components of the inactivation curve. We detect both a fast and a novel slower component of inactivation, and we show that the β3-subunit increases

SUBMITTER: Cusdin FS 

PROVIDER: S-EPMC2963402 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature