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1lir
From Proteopedia
(New page: 200px<br /><applet load="1lir" size="450" color="white" frame="true" align="right" spinBox="true" caption="1lir" /> '''LQ2 FROM LEIURUS QUINQUESTRIATUS, NMR, 22 ST...) |
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| - | [[Image:1lir.gif|left|200px]]<br /><applet load="1lir" size=" | + | [[Image:1lir.gif|left|200px]]<br /><applet load="1lir" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1lir" /> | caption="1lir" /> | ||
'''LQ2 FROM LEIURUS QUINQUESTRIATUS, NMR, 22 STRUCTURES'''<br /> | '''LQ2 FROM LEIURUS QUINQUESTRIATUS, NMR, 22 STRUCTURES'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Lq2 is a unique scorpion toxin. Acting from the extracellular side, Lq2 | + | Lq2 is a unique scorpion toxin. Acting from the extracellular side, Lq2 blocks the ion conduction pore in not only the voltage- and Ca2+ -activated channels, but also the inward-rectifier K+ channels. This finding argues that the three-dimensional structures of the pores in these K+ channels are similar. However, the amino acid sequences that form the external part of the pore are minimally conserved among the various classes of K+ channels. Because Lq2 can bind to all the three classes of K+ channels, we can use Lq2 as a structural probe to examine how the non-conserved pore-forming sequences are arranged in space to form similar pore structures. In the present study, we determined the three-dimensional structure of Lq2 using nuclear magnetic resonance (NMR) techniques. Lq2 consists of an alpha-helix (residues S10 to L20) and a beta-sheet, connected by an alphabeta3 loop (residues N22 to N24). The beta-sheet has two well-defined anti-parallel strands (residues G26 to M29 and residues K32 to C35), which are connected by a type I' beta-turn centered between residues N30 and K31. The N-terminal segment (residues Z1 to T8) appears to form a quasi-third strand of the beta-sheet. |
==About this Structure== | ==About this Structure== | ||
| - | 1LIR is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Leiurus_quinquestriatus_hebraeus Leiurus quinquestriatus hebraeus]. Full crystallographic information is available from [http:// | + | 1LIR is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Leiurus_quinquestriatus_hebraeus Leiurus quinquestriatus hebraeus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LIR OCA]. |
==Reference== | ==Reference== | ||
| Line 17: | Line 17: | ||
[[Category: Darbon, H.]] | [[Category: Darbon, H.]] | ||
[[Category: Jin, W.]] | [[Category: Jin, W.]] | ||
| - | [[Category: Lewis, J | + | [[Category: Lewis, J H.]] |
[[Category: Lu, Z.]] | [[Category: Lu, Z.]] | ||
| - | [[Category: Renisio, J | + | [[Category: Renisio, J G.]] |
[[Category: inward rectifier potassium channel]] | [[Category: inward rectifier potassium channel]] | ||
[[Category: neurotoxin]] | [[Category: neurotoxin]] | ||
| Line 25: | Line 25: | ||
[[Category: scorpion]] | [[Category: scorpion]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:45:22 2008'' |
Revision as of 11:45, 21 February 2008
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LQ2 FROM LEIURUS QUINQUESTRIATUS, NMR, 22 STRUCTURES
Overview
Lq2 is a unique scorpion toxin. Acting from the extracellular side, Lq2 blocks the ion conduction pore in not only the voltage- and Ca2+ -activated channels, but also the inward-rectifier K+ channels. This finding argues that the three-dimensional structures of the pores in these K+ channels are similar. However, the amino acid sequences that form the external part of the pore are minimally conserved among the various classes of K+ channels. Because Lq2 can bind to all the three classes of K+ channels, we can use Lq2 as a structural probe to examine how the non-conserved pore-forming sequences are arranged in space to form similar pore structures. In the present study, we determined the three-dimensional structure of Lq2 using nuclear magnetic resonance (NMR) techniques. Lq2 consists of an alpha-helix (residues S10 to L20) and a beta-sheet, connected by an alphabeta3 loop (residues N22 to N24). The beta-sheet has two well-defined anti-parallel strands (residues G26 to M29 and residues K32 to C35), which are connected by a type I' beta-turn centered between residues N30 and K31. The N-terminal segment (residues Z1 to T8) appears to form a quasi-third strand of the beta-sheet.
About this Structure
1LIR is a Single protein structure of sequence from Leiurus quinquestriatus hebraeus. Full crystallographic information is available from OCA.
Reference
Solution structure of potassium channel-inhibiting scorpion toxin Lq2., Renisio JG, Lu Z, Blanc E, Jin W, Lewis JH, Bornet O, Darbon H, Proteins. 1999 Mar 1;34(4):417-26. PMID:10081954
Page seeded by OCA on Thu Feb 21 13:45:22 2008
