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1i9k
From Proteopedia
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| - | [[Image:1i9k.png|left|200px]] | ||
| - | + | ==THE RNA I-MOTIF== | |
| + | <StructureSection load='1i9k' size='340' side='right'caption='[[1i9k]]' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[1i9k]] is a 4 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1I9K OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1I9K FirstGlance]. <br> | ||
| + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</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=1i9k FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1i9k OCA], [https://pdbe.org/1i9k PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1i9k RCSB], [https://www.ebi.ac.uk/pdbsum/1i9k PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1i9k ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | Oligodeoxynucleotides with stretches of cytidine residues associate into a four-stranded structure, the i-motif, in which two head-to-tail, intercalated, parallel-stranded duplexes are held together by hemiprotonated C.C+ pairs. We have investigated the possibility of forming an i-motif structure with C-rich ribonucleic acids. The four C-rich RNAs studied, r(UC5), r(C5), r(C5U) and r(UC3), associate into multiple intercalated structures at acidic pH. r(UC5) forms two i-motif structures that differ by their intercalation topologies. We report on a structural study of the main form and we analyze the small conformational differences found by comparison with the DNA i-motif. The stacking topology of the main structure avoids one of the six 2'-OH/2'-OH repulsive contacts expected in a fully intercalated structure. The C3'-endo pucker of the RNA sugars and the orientation of the intercalated C.C+ pairs result in a modest widening of the narrow grooves at the steps where the hydroxyl groups are in close contact. The free energy of the RNA i-motif, on average -4 kJ mol(-1) per C.C+ pair, is half of the value found in DNA i-motif structures. | ||
| - | + | The RNA i-motif.,Snoussi K, Nonin-Lecomte S, Leroy JL J Mol Biol. 2001 May 25;309(1):139-53. PMID:11491284<ref>PMID:11491284</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | == | + | <div class="pdbe-citations 1i9k" style="background-color:#fffaf0;"></div> |
| - | [[ | + | == References == |
| - | [[Category: Lerou | + | <references/> |
| - | [[Category: Nonin-Lecomte | + | __TOC__ |
| - | [[Category: Snoussi | + | </StructureSection> |
| - | + | [[Category: Large Structures]] | |
| - | + | [[Category: Lerou JL]] | |
| + | [[Category: Nonin-Lecomte S]] | ||
| + | [[Category: Snoussi K]] | ||
Current revision
THE RNA I-MOTIF
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