1a68
From Proteopedia
(New page: 200px<br /><applet load="1a68" size="450" color="white" frame="true" align="right" spinBox="true" caption="1a68, resolution 1.8Å" /> '''CRYSTAL STRUCTURE OF ...) |
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| - | [[Image:1a68.jpg|left|200px]]<br /><applet load="1a68" size=" | + | [[Image:1a68.jpg|left|200px]]<br /><applet load="1a68" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1a68, resolution 1.8Å" /> | caption="1a68, resolution 1.8Å" /> | ||
'''CRYSTAL STRUCTURE OF THE TETRAMERIZATION DOMAIN OF THE SHAKER POTASSIUM CHANNEL'''<br /> | '''CRYSTAL STRUCTURE OF THE TETRAMERIZATION DOMAIN OF THE SHAKER POTASSIUM CHANNEL'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Voltage-dependent, ion-selective channels such as Na+, Ca2+ and K+ channel | + | Voltage-dependent, ion-selective channels such as Na+, Ca2+ and K+ channel proteins function as tetrameric assemblies of identical or similar subunits. The clustering of four subunits is thought to create an aqueous pore centred at the four-fold symmetry axis. The highly conserved, amino-terminal cytoplasmic domain (approximately 130 amino acids) immediately preceding the first putative transmembrane helix S1 is designated T1. It is known to confer specificity for tetramer formation, so the heteromeric assembly of K+-channel subunits is an important mechanism for the observed channel diversity. We have determined the crystal structure of the T1 domain of a Shaker potassium channel at 1.55 A resolution. The structure reveals that four identical subunits are arranged in a four-fold symmetry surrounding a centrally located pore about 20 A in length. Subfamily-specific assembly is provided primarily by polar interactions encoded in a conserved set of amino acids at its tetramerization interface. Most highly conserved amino acids in the T1 domain of all known potassium channels are found in the core of the protein, indicating a common structural framework for the tetramer assembly. |
==About this Structure== | ==About this Structure== | ||
| - | 1A68 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Aplysia_californica Aplysia californica]. Full crystallographic information is available from [http:// | + | 1A68 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Aplysia_californica Aplysia californica]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1A68 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Choe, S.]] | [[Category: Choe, S.]] | ||
[[Category: Kreusch, A.]] | [[Category: Kreusch, A.]] | ||
| - | [[Category: Pfaffinger, P | + | [[Category: Pfaffinger, P J.]] |
| - | [[Category: Stevens, C | + | [[Category: Stevens, C F.]] |
| - | [[Category: aplysia kv1 | + | [[Category: aplysia kv1 1]] |
[[Category: potassium channels]] | [[Category: potassium channels]] | ||
[[Category: tetramerization domain]] | [[Category: tetramerization domain]] | ||
[[Category: x-ray structure]] | [[Category: x-ray structure]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:41:25 2008'' |
Revision as of 09:41, 21 February 2008
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CRYSTAL STRUCTURE OF THE TETRAMERIZATION DOMAIN OF THE SHAKER POTASSIUM CHANNEL
Overview
Voltage-dependent, ion-selective channels such as Na+, Ca2+ and K+ channel proteins function as tetrameric assemblies of identical or similar subunits. The clustering of four subunits is thought to create an aqueous pore centred at the four-fold symmetry axis. The highly conserved, amino-terminal cytoplasmic domain (approximately 130 amino acids) immediately preceding the first putative transmembrane helix S1 is designated T1. It is known to confer specificity for tetramer formation, so the heteromeric assembly of K+-channel subunits is an important mechanism for the observed channel diversity. We have determined the crystal structure of the T1 domain of a Shaker potassium channel at 1.55 A resolution. The structure reveals that four identical subunits are arranged in a four-fold symmetry surrounding a centrally located pore about 20 A in length. Subfamily-specific assembly is provided primarily by polar interactions encoded in a conserved set of amino acids at its tetramerization interface. Most highly conserved amino acids in the T1 domain of all known potassium channels are found in the core of the protein, indicating a common structural framework for the tetramer assembly.
About this Structure
1A68 is a Single protein structure of sequence from Aplysia californica. Full crystallographic information is available from OCA.
Reference
Crystal structure of the tetramerization domain of the Shaker potassium channel., Kreusch A, Pfaffinger PJ, Stevens CF, Choe S, Nature. 1998 Apr 30;392(6679):945-8. PMID:9582078
Page seeded by OCA on Thu Feb 21 11:41:25 2008
