View source for 6rs3


==2'-F-riboguanosine modified G-quadruplex with V-loop==
<StructureSection load='6rs3' size='340' side='right'caption='[[6rs3]], [[NMR_Ensembles_of_Models | 10 NMR models]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6rs3]] is a 1 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6RS3 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6RS3 FirstGlance]. <br>
</td></tr><tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=GF2:2-DEOXY-2-FLUOROGUANOSINE+5-(DIHYDROGEN+PHOSPHATE)'>GF2</scene></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=6rs3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6rs3 OCA], [http://pdbe.org/6rs3 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6rs3 RCSB], [http://www.ebi.ac.uk/pdbsum/6rs3 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6rs3 ProSAT]</span></td></tr>
</table>
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== Publication Abstract from PubMed ==
A DNA G-quadruplex adopting a (3+1) hybrid structure was modified in two adjacent syn positions of the antiparallel strand with anti-favoring 2'-deoxy-2'-fluoro-riboguanosine (FrG) analogs. The two substitutions promoted a structural rearrangement to a topology with the 5'-terminal G residue located in the central tetrad and the two modified residues linked by a V-shaped zero-nucleotide loop. Strikingly, whereas a sugar pucker in the preferred north domain is found for both modified nucleotides, the FrG analog preceding the V-loop is forced to adopt the unfavored syn conformation in the new quadruplex fold. Apparently, a preferred C3'-endo sugar pucker within the V-loop architecture outweighs the propensity of the FrG analog to adopt an anti glycosidic conformation. Refolding into a V-loop topology is likewise observed for a sequence modified at corresponding positions with two riboguanosine substitutions. In contrast, 2'-F-arabinoguanosine analogs with their favored south-east sugar conformation do not support formation of the V-loop topology. Examination of known G-quadruplexes with a V-shaped loop highlights the critical role of the sugar conformation for this distinct structural motif.

Sugar Puckering Drives G-Quadruplex Refolding: Implications for V-Shaped Loops.,Haase L, Dickerhoff J, Weisz K Chemistry. 2019 Oct 14. doi: 10.1002/chem.201904044. PMID:31609483<ref>PMID:31609483</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 6rs3" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Haase, L]]
[[Category: Weisz, K]]
[[Category: Dna]]
[[Category: G-quadruplex]]
[[Category: V-loop]]