Solution structure of extracellular loop of human β4 subunit of BK channel and its biological implication on ChTX sensitivity.

ABSTRACT: Large-conductance Ca²⁺- and voltage-dependent K⁺ (BK) channels display diverse biological functions while their pore-forming α subunit is coded by a single Slo1 gene. The variety of BK channels is correlated with the effects of BKα coexpression with auxiliary β (β1-β4) subunits, as well as newly defined γ subunits. Charybdotoxin (ChTX) blocks BK channel through physically occluding the K⁺-conduction pore. Human brain enriched β4 subunit (hβ4) alters the conductance-voltage curve, slows activation and deactivation time courses of BK channels. Its extracellular loop (hβ4-loop) specifically impedes ChTX to bind BK channel pore. However, the structure of β4 subunit's extracellular loop and the molecular mechanism for gating kinetics, toxin sensitivity of BK cha

SUBMITTER: Wang Y 

PROVIDER: S-EPMC5854672 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature