View source for 2ydh


==Crystal structure of the SAM-I riboswitch A94G U34 G18U G19U variant in complex with SAM==
<StructureSection load='2ydh' size='340' side='right'caption='[[2ydh]], [[Resolution|resolution]] 2.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2ydh]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Caldanaerobacter_subterraneus_subsp._tengcongensis Caldanaerobacter subterraneus subsp. tengcongensis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2YDH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2YDH FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BA:BARIUM+ION'>BA</scene>, <scene name='pdbligand=SAM:S-ADENOSYLMETHIONINE'>SAM</scene></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=2ydh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ydh OCA], [https://pdbe.org/2ydh PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ydh RCSB], [https://www.ebi.ac.uk/pdbsum/2ydh PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ydh ProSAT]</span></td></tr>
</table>
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== Publication Abstract from PubMed ==
The kink turn is a widespread RNA motif that introduces an acute kink into the axis of duplex RNA, typically comprising a bulge followed by a GA and AG pairs. The kinked conformation is stabilized by metal ions, or the binding of proteins including L7Ae. We now demonstrate a third mechanism for the stabilization of k-turn structure, involving tertiary interactions within a larger RNA structure. The SAM-I riboswitch contains an essential standard k-turn sequence that kinks a helix so that its terminal loop can make a long-range interaction. We find that some sequence variations in the k-turn within the riboswitch do not prevent SAM binding, despite preventing the folding of the k-turn in isolation. Furthermore, two crystal structures show that the sequence-variant k-turns are conventionally folded within the riboswitch. This study shows that the folded structure of the k-turn can be stabilized by tertiary interactions within a larger RNA structure.

RNA tertiary interactions in a riboswitch stabilize the structure of a kink turn.,Schroeder KT, Daldrop P, Lilley DM Structure. 2011 Sep 7;19(9):1233-40. PMID:21893284<ref>PMID:21893284</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2ydh" style="background-color:#fffaf0;"></div>

==See Also==
*[[Riboswitch 3D structures|Riboswitch 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Caldanaerobacter subterraneus subsp. tengcongensis]]
[[Category: Large Structures]]
[[Category: Daldrop P]]
[[Category: Lilley DMJ]]
[[Category: Schroeder KT]]