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2mel

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Revision as of 01:23, 12 September 2015

NMR solution structure of the GS-TAMAPIN MUTATION R7A

Structural highlights

2mel is a 1 chain structure. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	2me7, 2men, 2meo
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum

Function

[KAX54_MESTA] Blocks small conductance calcium-activated potassium channels in pyramidal neurons of the hippocampus. Displays a unique, remarkable selectivity for SK2/KCNN2 versus SK1/KCNN1 and SK3/KCNN3 channels.^[1]

Publication Abstract from PubMed

The scorpion toxin tamapin displays the most potent and selective blockage against KCa2.2 channels known to date. In this work, we report the biosynthesis, three-dimensional structure, and cytotoxicity on cancer cell lines (Jurkat E6-1 and human mammary breast cancer MDA-MB-231) of recombinant tamapin and five related peptides bearing mutations on residues (R6A,R7A, R13A, R6A-R7A, and GS-tamapin) that were previously suggested to be important for tamapin's activity. The indicated cell lines were used as they constitutively express KCa2.2 channels. The studied toxin-like peptides displayed lethal responses on Jurkat T cells and breast cancer cells; their effect is dose- and time-dependent with IC50 values in the nanomolar range. The order of potency is r-tamapin > GS-tamapin > R6A > R13A > R6A-R7A > R7A for Jurkat T cells and r-tamapin > R7A for MDA-MB-231 breast cancer cells. Our structural determination by NMR demonstrated that r-tamapin preserves the folding of the alphaKTx5 subfamily and that neither single nor double alanine mutations affect the three-dimensional structure of the wild-type peptide. In contrast, our activity assays show that changes in cytotoxicity are related to the chemical nature of certain residues. Our results suggest that the toxic activity of r-tamapin on Jurkat and breast cancer cells could be mediated by the interaction of charged residues in tamapin with KCa2.2 channels via the apoptotic cell death pathway.

Cytotoxicity of Recombinant Tamapin and Related Toxin-Like Peptides on Model Cell Lines.,Ramirez-Cordero B, Toledano Y, Cano-Sanchez P, Hernandez-Lopez R, Flores-Solis D, Saucedo-Yanez AL, Chavez-Uribe I, Brieba LG, Del Rio-Portilla F Chem Res Toxicol. 2014 May 12. PMID:24821061^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Pedarzani P, D'hoedt D, Doorty KB, Wadsworth JD, Joseph JS, Jeyaseelan K, Kini RM, Gadre SV, Sapatnekar SM, Stocker M, Strong PN. Tamapin, a venom peptide from the Indian red scorpion (Mesobuthus tamulus) that targets small conductance Ca2+-activated K+ channels and afterhyperpolarization currents in central neurons. J Biol Chem. 2002 Nov 29;277(48):46101-9. Epub 2002 Sep 17. PMID:12239213 doi:http://dx.doi.org/10.1074/jbc.M206465200
↑ Ramirez-Cordero B, Toledano Y, Cano-Sanchez P, Hernandez-Lopez R, Flores-Solis D, Saucedo-Yanez AL, Chavez-Uribe I, Brieba LG, Del Rio-Portilla F. Cytotoxicity of Recombinant Tamapin and Related Toxin-Like Peptides on Model Cell Lines. Chem Res Toxicol. 2014 May 12. PMID:24821061 doi:http://dx.doi.org/10.1021/tx4004193

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 See Also
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/2mel"

@@ Line 4: / Line 4: @@
 <table><tr><td colspan='2'>[[2mel]] is a 1 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2MEL OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2MEL FirstGlance]. <br>
 </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2me7|2me7]], [[2men|2men]], [[2meo|2meo]]</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=2mel FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2mel OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2mel RCSB], [http://www.ebi.ac.uk/pdbsum/2mel PDBsum]</span></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=2mel FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2mel OCA], [http://pdbe.org/2mel PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2mel RCSB], [http://www.ebi.ac.uk/pdbsum/2mel PDBsum]</span></td></tr>
 </table>
 == Function ==
@@ Line 16: / Line 16: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 2mel" style="background-color:#fffaf0;"></div>
+==See Also==
+*[[Potassium channel toxin|Potassium channel toxin]]
 == References ==
 <references/>

2mel

From Proteopedia

Revision as of 01:23, 12 September 2015

NMR solution structure of the GS-TAMAPIN MUTATION R7A

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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