View source for 6gn4


==tc-DNA/tc-DNA duplex==
<StructureSection load='6gn4' size='340' side='right'caption='[[6gn4]], [[NMR_Ensembles_of_Models | 10 NMR models]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6gn4]] is a 2 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6GN4 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6GN4 FirstGlance]. <br>
</td></tr><tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=EAN:'>EAN</scene>, <scene name='pdbligand=F4Q:'>F4Q</scene>, <scene name='pdbligand=F7H:'>F7H</scene>, <scene name='pdbligand=F7K:'>F7K</scene>, <scene name='pdbligand=TCJ:'>TCJ</scene>, <scene name='pdbligand=TCY:(2R,3AS,4AR,5AR,5BS)-2-(6-AMINO-9H-PURIN-9-YL)-3A-HYDROXYHEXAHYDROCYCLOPROPA[4,5]CYCLOPENTA[1,2-B]FURAN-5A(4H)-YL+DIHYDROGEN+PHOSPHATE'>TCY</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[6gmy|6gmy]]</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=6gn4 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6gn4 OCA], [http://pdbe.org/6gn4 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6gn4 RCSB], [http://www.ebi.ac.uk/pdbsum/6gn4 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6gn4 ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Tc-DNA is a conformationally constrained oligonucleotide analogue which shows significant increase in thermal stability when hybridized with RNA, DNA or tc-DNA. Remarkably, recent studies revealed that tc-DNA antisense oligonucleotides (AO) hold great promise for the treatment of Duchenne muscular dystrophy and spinal muscular atrophy. To date, no high-resolution structural data is available for fully modified tc-DNA duplexes and little is known about the origins of their enhanced thermal stability. Here, we report the structures of a fully modified tc-DNA oligonucleotide paired with either complementary RNA, DNA or tc-DNA. All three investigated duplexes maintain a right-handed helical structure with Watson-Crick base pairing and overall geometry intermediate between A- and B-type, but closer to A-type structures. All sugars of the tc-DNA and RNA residues adopt a North conformation whereas the DNA deoxyribose are found in a South-East-North conformation equilibrium. The conformation of the tc-DNA strand in the three determined structures is nearly identical and despite the different nature and local geometry of the complementary strand, the overall structures of the examined duplexes are very similar suggesting that the tc-DNA strand dominates the duplex structure.

NMR solution structure of tricyclo-DNA containing duplexes: insight into enhanced thermal stability and nuclease resistance.,Istrate A, Johannsen S, Istrate A, Sigel RKO, Leumann CJ Nucleic Acids Res. 2019 Mar 27. pii: 5420530. doi: 10.1093/nar/gkz197. PMID:30916334<ref>PMID:30916334</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6gn4" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Istrate, A]]
[[Category: Johannsen, S]]
[[Category: Leumann, C]]
[[Category: Sigel, R K.O]]
[[Category: Dna]]
[[Category: Modified nucleic acid]]
[[Category: Modified oligonucleotide]]
[[Category: Tc-dna]]
[[Category: Tricyclo-dna]]