Publication Date:
2009-12-19
Description:
Inward-rectifier potassium (K+) channels conduct K+ ions most efficiently in one direction, into the cell. Kir2 channels control the resting membrane voltage in many electrically excitable cells, and heritable mutations cause periodic paralysis and cardiac arrhythmia. We present the crystal structure of Kir2.2 from chicken, which, excluding the unstructured amino and carboxyl termini, is 90% identical to human Kir2.2. Crystals containing rubidium (Rb+), strontium (Sr2+), and europium (Eu3+) reveal binding sites along the ion conduction pathway that are both conductive and inhibitory. The sites correlate with extensive electrophysiological data and provide a structural basis for understanding rectification. The channel's extracellular surface, with large structured turrets and an unusual selectivity filter entryway, might explain the relative insensitivity of eukaryotic inward rectifiers to toxins. These same surface features also suggest a possible approach to the development of inhibitory agents specific to each member of the inward-rectifier K+ channel family.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2819303/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2819303/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Tao, Xiao -- Avalos, Jose L -- Chen, Jiayun -- MacKinnon, Roderick -- P30 EB009998/EB/NIBIB NIH HHS/ -- R01 GM043949/GM/NIGMS NIH HHS/ -- R01 GM043949-10/GM/NIGMS NIH HHS/ -- R01 GM043949-11/GM/NIGMS NIH HHS/ -- R01 GM043949-12/GM/NIGMS NIH HHS/ -- R01 GM043949-13/GM/NIGMS NIH HHS/ -- R01 GM043949-14/GM/NIGMS NIH HHS/ -- R01 GM043949-15/GM/NIGMS NIH HHS/ -- R01 GM043949-16/GM/NIGMS NIH HHS/ -- R01 GM043949-17/GM/NIGMS NIH HHS/ -- R01 GM043949-18/GM/NIGMS NIH HHS/ -- R01 GM043949-19/GM/NIGMS NIH HHS/ -- R01 GM043949-20/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- New York, N.Y. -- Science. 2009 Dec 18;326(5960):1668-74. doi: 10.1126/science.1180310.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Molecular Neurobiology and Biophysics, Rockefeller University, Howard Hughes Medical Institute, 1230 York Avenue, New York, NY 10065, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20019282" target="_blank"〉PubMed〈/a〉
Keywords:
Amino Acid Motifs
;
Amino Acid Sequence
;
Animals
;
Binding Sites
;
Chickens
;
Cloning, Molecular
;
Crystallography, X-Ray
;
Europium/metabolism
;
Hydrogen Bonding
;
Hydrophobic and Hydrophilic Interactions
;
Models, Molecular
;
Molecular Sequence Data
;
Oocytes
;
Patch-Clamp Techniques
;
Potassium/metabolism
;
Potassium Channel Blockers/pharmacology
;
Potassium Channels, Inwardly Rectifying/antagonists &
;
inhibitors/*chemistry/metabolism
;
Protein Structure, Secondary
;
Protein Structure, Tertiary
;
Protein Subunits/chemistry
;
Rubidium/metabolism
;
Sequence Alignment
;
Strontium/metabolism
;
Xenopus laevis
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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