The Pore, not Cytoplasmic Domains, Underlies Inactivation in a Prokaryotic Sodium Channel

From: Biophysical Journal | Date: July 1, 2005| Author: Bladen, Christopher; Diao, Catherine; Et al; Winkfein, Robert; Pavlov, Evgeny | Copyright information

ABSTRACT

Kinetics and voltage dependence of inactivation of a prokaryotic voltage-gated sodium channel (NaChBac) were investigated in an effort to understand its molecular mechanism. NaChBac inactivation kinetics show strong, bell-shaped voltage dependence with characteristic time constants ranging from ~50 ms at depolarized voltages to a maximum of ~100 s at the inactivation midpoint. Activation and inactivation parameters for four different covalently linked tandem dimer or tandem te...

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