Structural Basis for Competition between Drug Binding and Kvβ1.3 Accessory Subunit-Induced N-Type Inactivation of Kv1.5 Channels

@article{Decher2005StructuralBF,
  title={Structural Basis for Competition between Drug Binding and Kv$\beta$1.3 Accessory Subunit-Induced N-Type Inactivation of Kv1.5 Channels},
  author={Niels Decher and Pradeep Kumar and Teresa Gonzalez and Vijay Renigunta and Michael C Sanguinetti},
  journal={Molecular Pharmacology},
  year={2005},
  volume={68},
  pages={1005 - 995}
}
Kvβ subunits are accessory proteins that modify gating of Kv1 channels. Kvβ1.3 subunits bind to the N termini of Kv1.5 α-subunits and induce fast N-type inactivation, slow the rate of deactivation, and alter the voltage dependence and kinetics of channel activation. The N terminus of a Kvβ subunit and quaternary ammonium compounds bind to the inner pore of Kv1 channels; however, it is unknown to what extent the pore binding sites for drugs and Kvβ subunits overlap. Here, we used site-directed… Expand
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