Long-pore electrostatics in inward-rectifi er potassium channels
Journal of General Physiology, ISSN: 1540-7748, Vol: 132, Issue: 6, Page: 613-632
2008
- 43Citations
- 45Captures
Metric Options: Counts1 Year3 YearSelecting the 1-year or 3-year option will change the metrics count to percentiles, illustrating how an article or review compares to other articles or reviews within the selected time period in the same journal. Selecting the 1-year option compares the metrics against other articles/reviews that were also published in the same calendar year. Selecting the 3-year option compares the metrics against other articles/reviews that were also published in the same calendar year plus the two years prior.
Example: if you select the 1-year option for an article published in 2019 and a metric category shows 90%, that means that the article or review is performing better than 90% of the other articles/reviews published in that journal in 2019. If you select the 3-year option for the same article published in 2019 and the metric category shows 90%, that means that the article or review is performing better than 90% of the other articles/reviews published in that journal in 2019, 2018 and 2017.
Citation Benchmarking is provided by Scopus and SciVal and is different from the metrics context provided by PlumX Metrics.
Example: if you select the 1-year option for an article published in 2019 and a metric category shows 90%, that means that the article or review is performing better than 90% of the other articles/reviews published in that journal in 2019. If you select the 3-year option for the same article published in 2019 and the metric category shows 90%, that means that the article or review is performing better than 90% of the other articles/reviews published in that journal in 2019, 2018 and 2017.
Citation Benchmarking is provided by Scopus and SciVal and is different from the metrics context provided by PlumX Metrics.
Metrics Details
- Citations43
- Citation Indexes43
- 43
- CrossRef36
- Captures45
- Readers45
- 45
Article Description
Inward-rectifi er potassium (Kir) channels differ from the canonical K + channel structure in that they possess a long extended pore ( - 85 Å ) for ion conduction that reaches deeply into the cytoplasm. This unique structural feature is presumably involved in regulating functional properties specifi c to Kir channels, such as conductance, rectifi cation block, and ligand-dependent gating. To elucidate the underpinnings of these functional roles, we examine the electrostatics of an ion along this extended pore. Homology models are constructed based on the open-state model of KirBac1.1 for four mammalian Kir channels: Kir1.1/ROMK, Kir2.1/IRK, Kir3.1/GIRK, and Kir6.2/KATP. By solving the Poisson-Boltzmann equation, the electrostatic free energy of a K + ion is determined along each pore, revealing that mammalian Kir channels provide a favorable environment for cations and suggesting the existence of high-density regions in the cytoplasmic domain and cavity. The contribution from the reaction fi eld (the selfenergy arising from the dielectric polarization induced by the ion ' s charge in the complex geometry of the pore) is unfavorable inside the long pore. However, this is well compensated by the electrostatic interaction with the static fi eld arising from the protein charges and shielded by the dielectric surrounding. Decomposition of the static fi eld provides a list of residues that display remarkable correspondence with existing mutagenesis data identifying amino acids that affect conduction and rectifi cation. Many of these residues demonstrate interactions with the ion over long distances, up to 40 Å , suggesting that mutations potentially affect ion or blocker energetics over the entire pore. These results provide a foundation for understanding ion interactions in Kir channels and extend to the study of ion permeation, block, and gating in long, cation-specifi c pores. © 2008 Palmer and Andersen.
Bibliographic Details
http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=59649091228&origin=inward; http://dx.doi.org/10.1085/jgp.200810068; http://www.ncbi.nlm.nih.gov/pubmed/19001143; https://rupress.org/jgp/article/132/6/613/43887/Long-pore-Electrostatics-in-Inward-rectifier; https://dx.doi.org/10.1085/jgp.200810068
Rockefeller University Press
Provide Feedback
Have ideas for a new metric? Would you like to see something else here?Let us know