4e5c

<StructureSection load='4e5c' size='340' side='right' caption='[[4e5c]], [[Resolution|resolution]] 1.70&Aring;' scene=''>

<table><tr><td colspan='2'>[[4e5c]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4E5C OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4E5C FirstGlance]. <br>

</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4e48|4e48]]</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=4e5c FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4e5c OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4e5c RCSB], [http://www.ebi.ac.uk/pdbsum/4e5c PDBsum]</span></td></tr>

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== Publication Abstract from PubMed ==

Human genetic trinucleotide repeat expansion diseases (TREDs) are characterized by triplet repeat expansions, most frequently found as CNG-tracts in genome. At RNA level, such expansions suggestively result in formation of double-helical hairpins that become a potential source for small RNAs involved in RNA interference (RNAi). Here, we present three crystal structures of RNA fragments composed of triplet repeats CUG and CGG/CUG, as well as two crystal structures of same triplets in a protein-bound state. We show that both 20mer pG(CUG)(6)C and 19mer pGG(CGG)(3)(CUG)(2)CC form A-RNA duplexes, in which U.U or G.U mismatches are flanked/stabilized by two consecutive Watson-Crick G.C base pairs resulting in high-stacking GpC steps in every third position of the duplex. Despite interruption of this regularity in another 19mer, p(CGG)(3)C(CUG)(3), the oligonucleotide still forms regular double-helical structure, characterized, however, by 12 bp (rather than 11 bp) per turn. Analysis of newly determined molecular structures reveals the dynamic aspects of U.U and G.U mismatching within CNG-repetitive A-RNA and in a protein-bound state, as well as identifies an additional mode of U.U pairing essential for its dynamics and sheds the light on possible role of regularity of trinucleotide repeats for double-helical RNA structure. Findings are important for understanding the structural behavior of CNG-repetitive RNA double helices implicated in TREDs.

Structural dynamics of double-helical RNAs composed of CUG/CUG- and CUG/CGG-repeats.,Tamjar J, Katorcha E, Popov A, Malinina L J Biomol Struct Dyn. 2012 Jun 25. PMID:22731704<ref>PMID:22731704</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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== References ==

<references/>

[[Category: Malinina, L]]

[[Category: Popov, A]]

[[Category: Tamjar, J]]

[[Category: Rna]]

[[Category: Trinucleotide repeat expansion]]