Modification of the Na+ current conducted by the rat skeletal muscle α subunit by coexpression with a human brain β subunit

1432-2013

sodium channel ; skeletal muscle ; Xenopus

Springer Online Journal Archives 1860-2000

Medicine

Abstract Sodium channels are multimeric structures composed of α and β subunits. Oocytes injected with RNA encoding only the α subunit express voltage-gated Na+ currents. The kinetics of inactivation, however, are abnormal. Co-injection of rat brain α and β subunits modifies inactivation of INa such that it closely resembles endogenous currents [1]. Here we show that a β subunit derived from human brain directs the same functional modification of INa expressed by a rat skeletal muscle α subunit. This implies that functional domains for the interaction of α and β subunits are highly conserved across both tissues and species.

Electronic Resource