ArticleProceedings of the National Academy of Sciences of the United States of America2007
Structural insight into Ca2+ specificity in tetrameric cation channels.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2007. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 25 papers.
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25 citing papers in PubMed, 40 citations in OpenAlex.
- Physiological functions and pharmacological targeting of transient receptor potential channels.Pharmacological reviews · 2025Review
- From Selective Permeation to Physiology in Potassium Channels.Function (Oxford, England) · 2025Review
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- All atom NMDA receptor transmembrane domain model development and simulations in lipid bilayers and water.PloS one · 2017Article
- The Outer Pore and Selectivity Filter of TRPA1.PloS one · 2016Article
- Structural implications of weak Ca2+ block in Drosophila cyclic nucleotide-gated channels.The Journal of general physiology · 2015Article
- Molecular bases of NMDA receptor subtype-dependent properties.The Journal of physiology · 2015Review
- Article
- Does cation break the cyano bond? A critical evaluation of nitrile-cation interaction.Journal of molecular modeling · 2014Article
- Article
- Distinct gating mechanisms revealed by the structures of a multi-ligand gated K(+) channel.eLife · 2012Article
- Nonselective conduction in a mutated NaK channel with three cation-binding sites.Biophysical journal · 2012Article
- A single GluN2 subunit residue controls NMDA receptor channel properties via intersubunit interaction.Nature neuroscience · 2012Article
- Evolutionary and structural perspectives of plant cyclic nucleotide-gated cation channels.Frontiers in plant science · 2012Article
- Calcium-dependent decrease in the single-channel conductance of TRPV1.Pflugers Archiv : European journal of physiology · 2011Article
- Gating at the selectivity filter of ion channels that conduct Na+ and K+ ions.Biophysical journal · 2011Article
- Structural studies of ion selectivity in tetrameric cation channels.The Journal of general physiology · 2011Review
- Structural studies of ion permeation and Ca2+ blockage of a bacterial channel mimicking the cyclic nucleotide-gated channel pore.Proceedings of the National Academy of Sciences of the United States of America · 2011Article
- Tuning the ion selectivity of tetrameric cation channels by changing the number of ion binding sites.Proceedings of the National Academy of Sciences of the United States of America · 2011Article
- Semisynthesis of NaK, a Na(+) and K(+) conducting ion channel.Biochemistry · 2010Article
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Authors and funding
3 authors at 1 institution in 1 country.
Funding
Abstract
Apparent blockage of monovalent cation currents by the permeating blocker Ca(2+) is a physiologically essential phenomenon relevant to cyclic nucleotide-gated (CNG) channels. The recently determined crystal structure of a bacterial homolog of CNG channel pores, the NaK channel, revealed a Ca(2+) binding site at the extracellular entrance to the selectivity filter. This site is not formed by the side-chain carboxylate groups from the conserved acidic residue, Asp-66 in NaK, conventionally thought to directly chelate Ca(2+) in CNG channels, but rather by the backbone carbonyl groups of residue Gly-67. Here we present a detailed structural analysis of the NaK channel with a focus on Ca(2+) permeability and blockage. Our results confirm that the Asp-66 residue, although not involved in direct chelation of Ca(2+), plays an essential role in external Ca(2+) binding. Furthermore, we give evidence for the presence of a second Ca(2+) binding site within the NaK selectivity filter where monovalent cations also bind, providing a structural basis for Ca(2+) permeation through the NaK pore. Compared with other Ca(2+)-binding proteins, both sites in NaK present a novel mode of Ca(2+) chelation, using only backbone carbonyl oxygen atoms from residues in the selectivity filter. The external site is under indirect control by an acidic residue (Asp-66), making it Ca(2+)-specific. These findings give us a glimpse of the possible underlying mechanisms allowing Ca(2+) to act both as a permeating ion and blocker of CNG channels and raise the possibility of a similar chemistry governing Ca(2+) chelation in Ca(2+) channels.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.