Download MendeleyStructure of a eukaryotic cyclic-nucleotide-gated channel.
Li, M., Zhou, X., Wang, S., Michailidis, I., Gong, Y., Su, D., Li, H., Li, X., Yang, J.(2017) Nature 542: 60-65
- PubMed: 28099415
- DOI: https://doi.org/10.1038/nature20819
- Primary Citation of Related Structures:
5H3O - PubMed Abstract:
Cyclic-nucleotide-gated channels are essential for vision and olfaction. They belong to the voltage-gated ion channel superfamily but their activities are controlled by intracellular cyclic nucleotides instead of transmembrane voltage. Here we report a 3.5-Å-resolution single-particle electron cryo-microscopy structure of a cyclic-nucleotide-gated channel from Caenorhabditis elegans in the cyclic guanosine monophosphate (cGMP)-bound open state. The channel has an unusual voltage-sensor-like domain, accounting for its deficient voltage dependence. A carboxy-terminal linker connecting S6 and the cyclic-nucleotide-binding domain interacts directly with both the voltage-sensor-like domain and the pore domain, forming a gating ring that couples conformational changes triggered by cyclic nucleotide binding to the gate. The selectivity filter is lined by the carboxylate side chains of a functionally important glutamate and three rings of backbone carbonyls. This structure provides a new framework for understanding mechanisms of ion permeation, gating and channelopathy of cyclic-nucleotide-gated channels and cyclic nucleotide modulation of related channels.
Organizational Affiliation:
Department of Biological Sciences, Columbia University, New York, New York 10027, USA.
