Download MendeleySmall molecule modulation of the Drosophila Slo channel elucidated by cryo-EM.
Raisch, T., Brockmann, A., Ebbinghaus-Kintscher, U., Freigang, J., Gutbrod, O., Kubicek, J., Maertens, B., Hofnagel, O., Raunser, S.(2021) Nat Commun 12: 7164-7164
- PubMed: 34887422
- DOI: https://doi.org/10.1038/s41467-021-27435-w
- Primary Citation of Related Structures:
7PXE, 7PXF, 7PXG, 7PXH - PubMed Abstract:
Slowpoke (Slo) potassium channels display extraordinarily high conductance, are synergistically activated by a positive transmembrane potential and high intracellular Ca 2+ concentrations and are important targets for insecticides and antiparasitic drugs. However, it is unknown how these compounds modulate ion translocation and whether there are insect-specific binding pockets. Here, we report structures of Drosophila Slo in the Ca 2+ -bound and Ca 2+ -free form and in complex with the fungal neurotoxin verruculogen and the anthelmintic drug emodepside. Whereas the architecture and gating mechanism of Slo channels are conserved, potential insect-specific binding pockets exist. Verruculogen inhibits K + transport by blocking the Ca 2+ -induced activation signal and precludes K + from entering the selectivity filter. Emodepside decreases the conductance by suboptimal K + coordination and uncouples ion gating from Ca 2+ and voltage sensing. Our results expand the mechanistic understanding of Slo regulation and lay the foundation for the rational design of regulators of Slo and other voltage-gated ion channels.
Organizational Affiliation:
Department of Structural Biochemistry, Max Planck Institute of Molecular Physiology, 44227, Dortmund, Germany.
