This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1agt
From Proteopedia
(Difference between revisions)
| (4 intermediate revisions not shown.) | |||
| Line 1: | Line 1: | ||
| + | |||
==SOLUTION STRUCTURE OF THE POTASSIUM CHANNEL INHIBITOR AGITOXIN 2: CALIPER FOR PROBING CHANNEL GEOMETRY== | ==SOLUTION STRUCTURE OF THE POTASSIUM CHANNEL INHIBITOR AGITOXIN 2: CALIPER FOR PROBING CHANNEL GEOMETRY== | ||
| - | <StructureSection load='1agt' size='340' side='right' caption='[[1agt | + | <StructureSection load='1agt' size='340' side='right'caption='[[1agt]]' scene=''> |
== Structural highlights == | == Structural highlights == | ||
| - | <table><tr><td colspan='2'>[[1agt]] is a 1 chain structure with sequence from [ | + | <table><tr><td colspan='2'>[[1agt]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Leiurus_quinquestriatus_hebraeus Leiurus quinquestriatus hebraeus]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1AGT OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1AGT FirstGlance]. <br> |
| - | </td></tr><tr id=' | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</td></tr> |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[ | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1agt FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1agt OCA], [https://pdbe.org/1agt PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1agt RCSB], [https://www.ebi.ac.uk/pdbsum/1agt PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1agt ProSAT]</span></td></tr> |
</table> | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/KAX32_LEIHE KAX32_LEIHE] Potent inhibitor of the Shaker potassium channels and its mammalian homologs (Kv1.1/KCNA1, Kv1.3/KCNA3, Kv1.6/KCNA6) (Ki<1 nM for all channels) (PubMed:8204618, PubMed:20007782). Also blocks Kv1.2/KCNA2 (IC(50)=26.8 nM) (PubMed:8204618, PubMed:20007782). It also shows a weak interaction with nicotinic acetylcholine receptors (nAChR), suggesting it may weakly inhibit it (PubMed:31276191).<ref>PMID:20007782</ref> <ref>PMID:8204618</ref> | ||
== Evolutionary Conservation == | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | [[Image:Consurf_key_small.gif|200px|right]] | ||
Check<jmol> | Check<jmol> | ||
<jmolCheckbox> | <jmolCheckbox> | ||
| - | <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ag/1agt_consurf.spt"</scriptWhenChecked> | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ag/1agt_consurf.spt"</scriptWhenChecked> |
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | ||
<text>to colour the structure by Evolutionary Conservation</text> | <text>to colour the structure by Evolutionary Conservation</text> | ||
</jmolCheckbox> | </jmolCheckbox> | ||
| - | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/ | + | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1agt ConSurf]. |
<div style="clear:both"></div> | <div style="clear:both"></div> | ||
| - | <div style="background-color:#fffaf0;"> | ||
| - | == Publication Abstract from PubMed == | ||
| - | The structure of the potassium channel blocker agitoxin 2 was solved by solution NMR methods. The structure consists of a triple-stranded antiparallel beta-sheet and a single helix covering one face of the beta-sheet. The cysteine side chains connecting the beta-sheet and the helix form the core of the molecule. One edge of the beta-sheet and the adjacent face of the helix form the interface with the Shaker K+ channel. The fold of agitoxin is homologous to the previously determined folds of scorpion venom toxins. However, agitoxin 2 differs significantly from the other channel blockers in the specificity of its interactions. This study was thus focused on a precise characterization of the surface residues at the face of the protein interacting with the Shaker K+ channel. The rigid toxin molecule can be used to estimate dimensions of the potassium channel. Surface-exposed residues, Arg24, Lys27, and Arg31 of the beta-sheet, have been identified from mutagenesis studies as functionally important for blocking the Shaker K+ channel. The sequential and spatial locations of Arg24 and Arg31 are not conserved among the homologous toxins. Knowledge on the details of the channel-binding sites of agitoxin 2 formed a basis for site-directed mutagenesis studies of the toxin and the K+ channel sequences. Observed interactions between mutated toxin and channel are being used to elucidate the channel structure and mechanisms of channel-toxin interactions. | ||
| - | |||
| - | Solution structure of the potassium channel inhibitor agitoxin 2: caliper for probing channel geometry.,Krezel AM, Kasibhatla C, Hidalgo P, MacKinnon R, Wagner G Protein Sci. 1995 Aug;4(8):1478-89. PMID:8520473<ref>PMID:8520473</ref> | ||
| - | |||
| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| - | </div> | ||
==See Also== | ==See Also== | ||
| - | *[[Potassium channel toxin|Potassium channel toxin]] | + | *[[Potassium channel toxin 3D structures|Potassium channel toxin 3D structures]] |
== References == | == References == | ||
<references/> | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
| + | [[Category: Large Structures]] | ||
[[Category: Leiurus quinquestriatus hebraeus]] | [[Category: Leiurus quinquestriatus hebraeus]] | ||
| - | [[Category: Hidalgo | + | [[Category: Hidalgo P]] |
| - | [[Category: Kasibhatla | + | [[Category: Kasibhatla C]] |
| - | [[Category: Krezel | + | [[Category: Krezel AM]] |
| - | [[Category: Mackinnon | + | [[Category: Mackinnon R]] |
| - | [[Category: Wagner | + | [[Category: Wagner G]] |
| - | + | ||
| - | + | ||
Current revision
SOLUTION STRUCTURE OF THE POTASSIUM CHANNEL INHIBITOR AGITOXIN 2: CALIPER FOR PROBING CHANNEL GEOMETRY
| |||||||||||

