4iqs

<StructureSection load='4iqs' size='340' side='right' caption='[[4iqs]], [[Resolution|resolution]] 2.60&Aring;' scene=''>

<table><tr><td colspan='2'>[[4iqs]] is a 6 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4IQS OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4IQS FirstGlance]. <br>

</td></tr><tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=US5:1-(5-O-PHOSPHONO-BETA-D-RIBOFURANOSYL)-4-SELANYLPYRIMIDIN-2(1H)-ONE'>US5</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=4iqs FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4iqs OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4iqs RCSB], [http://www.ebi.ac.uk/pdbsum/4iqs PDBsum]</span></td></tr>

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== Publication Abstract from PubMed ==

Unlike DNA, in addition to the 2'-OH group, uracil nucleobase and its modifications play essential roles in structure and function diversities of non-coding RNAs. Non-canonical U*U base pair is ubiquitous in non-coding RNAs, which are highly diversified. However, it is not completely clear how uracil plays the diversifing roles. To investigate and compare the uracil in U-A and U*U base pairs, we have decided to probe them with a selenium atom by synthesizing the novel 4-Se-uridine ((Se)U) phosphoramidite and Se-nucleobase-modified RNAs ((Se)U-RNAs), where the exo-4-oxygen of uracil is replaced by selenium. Our crystal structure studies of U-A and U*U pairs reveal that the native and Se-derivatized structures are virtually identical, and both U-A and U*U pairs can accommodate large Se atoms. Our thermostability and crystal structure studies indicate that the weakened H-bonding in U-A pair may be compensated by the base stacking, and that the stacking of the trans-Hoogsteen U*U pairs may stabilize RNA duplex and its junction. Our result confirms that the hydrogen bond (O4(...)H-C5) of the Hoogsteen pair is weak. Using the Se atom probe, our Se-functionalization studies reveal more insights into the U*U interaction and U-participation in structure and function diversification of nucleic acids.

Structural insights of non-canonical U*U pair and Hoogsteen interaction probed with Se atom.,Sheng J, Gan J, Soares AS, Salon J, Huang Z Nucleic Acids Res. 2013 Dec 1;41(22):10476-87. doi: 10.1093/nar/gkt799. Epub 2013, Sep 5. PMID:24013566<ref>PMID:24013566</ref>

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

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== References ==

<references/>

[[Category: Gan, J]]

[[Category: Huang, Z]]

[[Category: Sheng, J]]

[[Category: Soares, A]]

[[Category: Selenium rna]]