View source for 1nix


==THREE DIMENSIONAL SOLUTION STRUCTURE OF HAINANTOXIN-I BY 2D 1H-NMR==
<StructureSection load='1nix' size='340' side='right'caption='[[1nix]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1nix]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Haplopelma_hainanum Haplopelma hainanum]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NIX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1NIX FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR, 20 models</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NH2:AMINO+GROUP'>NH2</scene></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=1nix FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1nix OCA], [https://pdbe.org/1nix PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1nix RCSB], [https://www.ebi.ac.uk/pdbsum/1nix PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1nix ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/H1A01_CYRHA H1A01_CYRHA] Weakly blocks the rat SCN2A/SCN1B (Nav1.2/beta-1) sodium channel (IC(50)=68 uM) and the insect sodium channel para/tipE (IC(50)=4.3 uM), without altering the activation or inactivation kinetics (depressant toxin).<ref>PMID:14675784</ref> <ref>PMID:26429937</ref> 
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== Publication Abstract from PubMed ==
Hainantoxin-I is a novel peptide toxin, purified from the venom of the Chinese bird spider Selenocosmia hainana (=Ornithoctonus hainana). It includes 33 amino acid residues with a disulfide linkage of I-IV, II-V and III-VI, assigned by partial reduction and sequence analysis. Under two-electrode voltage-clamp conditions, hainantoxin-I can block rNa(v)1.2/beta(1) and the insect sodium channel para/tipE expressed in Xenopus laevis oocytes with IC(50) values of 68+/-6 microM and 4.3+/-0.3 microM respectively. The three-dimensional solution structure of hainantoxin-I belongs to the inhibitor cystine knot structural family determined by two-dimensional (1)H nuclear magnetic resonance techniques. Structural comparison of hainantoxin-I with those of other toxins suggests that the combination of the charged residues and a vicinal hydrophobic patch should be responsible for ligand binding. This is the first report of an insect sodium channel blocker from spider venom and it provides useful information for the structure-function relationship studies of insect sodium channels.

Function and solution structure of hainantoxin-I, a novel insect sodium channel inhibitor from the Chinese bird spider Selenocosmia hainana.,Li D, Xiao Y, Hu W, Xie J, Bosmans F, Tytgat J, Liang S FEBS Lett. 2003 Dec 18;555(3):616-22. PMID:14675784<ref>PMID:14675784</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1nix" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Haplopelma hainanum]]
[[Category: Large Structures]]
[[Category: Li D]]
[[Category: Liang S]]