|
|
(5 intermediate revisions not shown.) |
Line 1: |
Line 1: |
| + | |
| ==NMR structure of Alpha-Bungarotoxin== | | ==NMR structure of Alpha-Bungarotoxin== |
- | <StructureSection load='1ik8' size='340' side='right' caption='[[1ik8]], [[NMR_Ensembles_of_Models | 1 NMR models]]' scene=''> | + | <StructureSection load='1ik8' size='340' side='right'caption='[[1ik8]]' scene=''> |
| == Structural highlights == | | == Structural highlights == |
- | <table><tr><td colspan='2'>[[1ik8]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Bungarus_multicinctus Bungarus multicinctus]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1IK8 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1IK8 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[1ik8]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Bungarus_multicinctus Bungarus multicinctus]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1IK8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1IK8 FirstGlance]. <br> |
- | </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1hn7|1hn7]], [[1hoy|1hoy]]</td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR, 1 model</td></tr> |
- | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1ik8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ik8 OCA], [http://pdbe.org/1ik8 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1ik8 RCSB], [http://www.ebi.ac.uk/pdbsum/1ik8 PDBsum]</span></td></tr> | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1ik8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ik8 OCA], [https://pdbe.org/1ik8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1ik8 RCSB], [https://www.ebi.ac.uk/pdbsum/1ik8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1ik8 ProSAT]</span></td></tr> |
| </table> | | </table> |
| == Function == | | == Function == |
- | [[http://www.uniprot.org/uniprot/NXL1A_BUNMU NXL1A_BUNMU]] Binds with high affinity to muscular and neuronal (alpha-7, alpha-8, and alpha-9) nicotinic acetylcholine receptors. Produces peripheral paralysis by blocking neuromuscular transmission at the postsynaptic site. Blocks the extracellular increase of dopamine evoked by nicotine only at the higher dose (4.2 uM).<ref>PMID:9305882</ref> <ref>PMID:9840221</ref> | + | [https://www.uniprot.org/uniprot/3L21A_BUNMU 3L21A_BUNMU] Binds with high affinity to muscular (tested on Torpedo marmorata, Kd=0.4 nM) and neuronal (tested on chimeric alpha-7/CHRNA7, Kd=0.95 nM) nicotinic acetylcholine receptor (nAChR) and inhibits acetylcholine from binding to the receptor, thereby impairing neuromuscular and neuronal transmission (PubMed:9305882). It also shows an activity on GABA(A) receptors (PubMed:16549768, PubMed:25634239). It antagonises GABA-activated currents with high potency when tested on primary hippocampal neurons (PubMed:25634239). It inhibits recombinantly expressed GABA(A) receptors composed of alpha-2-beta-2-gamma-2 (GABRA2-GABRB2-GABRG2) subunits with high potency (62.3% inhibition at 20 uM of toxin) (PubMed:25634239). It also shows a weaker inhibition on GABA(A) receptors composed of alpha-1-beta-2-gamma-2 (GABRA1-GABRB2-GABRG2) subunits, alpha-4-beta-2-gamma-2 (GABRA4-GABRB2-GABRG2) subunits, and alpha-5-beta-2-gamma-2 (GABRA5-GABRB2-GABRG2) subunits (PubMed:25634239). A very weak inhibition is also observed on GABA(A) receptor composed of alpha-1-beta-3-gamma-2 (GABRA1-GABRB3-GABRG2) (PubMed:26221036). It has also been shown to bind and inhibit recombinant GABA(A) receptor beta-3/GABRB3 subunit (Kd=about 50 nM) (PubMed:16549768). In addition, it blocks the extracellular increase of dopamine evoked by nicotine only at the higher dose (4.2 uM) (PubMed:9840221).<ref>PMID:16549768</ref> <ref>PMID:25634239</ref> <ref>PMID:9305882</ref> <ref>PMID:9840221</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/ik/1ik8_consurf.spt"</scriptWhenChecked> | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ik/1ik8_consurf.spt"</scriptWhenChecked> |
- | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | + | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.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/chain_selection.php?pdb_ID=2ata ConSurf]. | + | </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=1ik8 ConSurf]. |
| <div style="clear:both"></div> | | <div style="clear:both"></div> |
| <div style="background-color:#fffaf0;"> | | <div style="background-color:#fffaf0;"> |
Line 29: |
Line 30: |
| | | |
| ==See Also== | | ==See Also== |
- | *[[Bungarotoxin|Bungarotoxin]] | + | *[[Bungarotoxin 3D structures|Bungarotoxin 3D structures]] |
| == References == | | == References == |
| <references/> | | <references/> |
Line 35: |
Line 36: |
| </StructureSection> | | </StructureSection> |
| [[Category: Bungarus multicinctus]] | | [[Category: Bungarus multicinctus]] |
- | [[Category: Ciutti, A]] | + | [[Category: Large Structures]] |
- | [[Category: Niccolai, N]] | + | [[Category: Ciutti A]] |
- | [[Category: Spiga, O]] | + | [[Category: Niccolai N]] |
- | [[Category: Alpha-bungarotoxin]] | + | [[Category: Spiga O]] |
- | [[Category: Nicotinic-acetilcholine receptor]]
| + | |
- | [[Category: Toxin]]
| + | |
| Structural highlights
Function
3L21A_BUNMU Binds with high affinity to muscular (tested on Torpedo marmorata, Kd=0.4 nM) and neuronal (tested on chimeric alpha-7/CHRNA7, Kd=0.95 nM) nicotinic acetylcholine receptor (nAChR) and inhibits acetylcholine from binding to the receptor, thereby impairing neuromuscular and neuronal transmission (PubMed:9305882). It also shows an activity on GABA(A) receptors (PubMed:16549768, PubMed:25634239). It antagonises GABA-activated currents with high potency when tested on primary hippocampal neurons (PubMed:25634239). It inhibits recombinantly expressed GABA(A) receptors composed of alpha-2-beta-2-gamma-2 (GABRA2-GABRB2-GABRG2) subunits with high potency (62.3% inhibition at 20 uM of toxin) (PubMed:25634239). It also shows a weaker inhibition on GABA(A) receptors composed of alpha-1-beta-2-gamma-2 (GABRA1-GABRB2-GABRG2) subunits, alpha-4-beta-2-gamma-2 (GABRA4-GABRB2-GABRG2) subunits, and alpha-5-beta-2-gamma-2 (GABRA5-GABRB2-GABRG2) subunits (PubMed:25634239). A very weak inhibition is also observed on GABA(A) receptor composed of alpha-1-beta-3-gamma-2 (GABRA1-GABRB3-GABRG2) (PubMed:26221036). It has also been shown to bind and inhibit recombinant GABA(A) receptor beta-3/GABRB3 subunit (Kd=about 50 nM) (PubMed:16549768). In addition, it blocks the extracellular increase of dopamine evoked by nicotine only at the higher dose (4.2 uM) (PubMed:9840221).[1] [2] [3] [4]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
A combinatorial library approach was used to produce synthetic peptides mimicking the snake neurotoxin binding site of nicotinic receptors. Among the sequences, which inhibited binding of alpha-bungarotoxin to muscle and neuronal nicotinic receptors, HRYYESSLPWYPD, a 14-amino acid peptide with considerably higher toxin-binding affinity than the other synthesized peptides, was selected, and the structure of its complex with the toxin was analyzed by NMR. Comparison of the solution structure of the free toxin and its complex with this peptide indicated that complex formation induced extensive conformational rearrangements mainly at finger II and the carboxy terminus of the protein. The peptidyl residues P10 and Y4 seemed to be critical for peptide folding and complex stability, respectively. The latter residue of the peptide strongly interacted with the protein by entering a small pocket delimited by D30, C33, S34, R36, and V39 toxin side chains.
NMR structure of alpha-bungarotoxin free and bound to a mimotope of the nicotinic acetylcholine receptor.,Scarselli M, Spiga O, Ciutti A, Bernini A, Bracci L, Lelli B, Lozzi L, Calamandrei D, Di Maro D, Klein S, Niccolai N Biochemistry. 2002 Feb 5;41(5):1457-63. PMID:11814338[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ McCann CM, Bracamontes J, Steinbach JH, Sanes JR. The cholinergic antagonist alpha-bungarotoxin also binds and blocks a subset of GABA receptors. Proc Natl Acad Sci U S A. 2006 Mar 28;103(13):5149-54. doi:, 10.1073/pnas.0600847103. Epub 2006 Mar 20. PMID:16549768 doi:http://dx.doi.org/10.1073/pnas.0600847103
- ↑ Hannan S, Mortensen M, Smart TG. Snake neurotoxin alpha-bungarotoxin is an antagonist at native GABA(A) receptors. Neuropharmacology. 2015 Jun;93:28-40. doi: 10.1016/j.neuropharm.2015.01.001. Epub, 2015 Jan 26. PMID:25634239 doi:http://dx.doi.org/10.1016/j.neuropharm.2015.01.001
- ↑ Servent D, Winckler-Dietrich V, Hu HY, Kessler P, Drevet P, Bertrand D, Menez A. Only snake curaremimetic toxins with a fifth disulfide bond have high affinity for the neuronal alpha7 nicotinic receptor. J Biol Chem. 1997 Sep 26;272(39):24279-86. PMID:9305882
- ↑ Dajas-Bailador F, Costa G, Dajas F, Emmett S. Effects of alpha-erabutoxin, alpha-bungarotoxin, alpha-cobratoxin and fasciculin on the nicotine-evoked release of dopamine in the rat striatum in vivo. Neurochem Int. 1998 Oct;33(4):307-12. PMID:9840221
- ↑ Scarselli M, Spiga O, Ciutti A, Bernini A, Bracci L, Lelli B, Lozzi L, Calamandrei D, Di Maro D, Klein S, Niccolai N. NMR structure of alpha-bungarotoxin free and bound to a mimotope of the nicotinic acetylcholine receptor. Biochemistry. 2002 Feb 5;41(5):1457-63. PMID:11814338
|