View source for 5xgu


==Escherichia coli. RNase R==
<StructureSection load='5xgu' size='340' side='right'caption='[[5xgu]], [[Resolution|resolution]] 1.85&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5xgu]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_DEC6A Escherichia coli DEC6A]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5XGU OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5XGU 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]] 1.846&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=5xgu FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5xgu OCA], [https://pdbe.org/5xgu PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5xgu RCSB], [https://www.ebi.ac.uk/pdbsum/5xgu PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5xgu ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
RNase R is a conserved exoribonuclease in the RNase II family that primarily participates in RNA decay in all kingdoms of life. RNase R degrades duplex RNA with a 3' overhang, suggesting that it has RNA unwinding activity in addition to its 3'-to-5' exoribonuclease activity. However, how RNase R coordinates RNA binding with unwinding to degrade RNA remains elusive. Here, we report the crystal structure of a truncated form of Escherichia coli RNase R (residues 87-725) at a resolution of 1.85 A. Structural comparisons with other RNase II family proteins reveal two open RNA-binding channels in RNase R and suggest a tri-helix 'wedge' region in the RNB domain that may induce RNA unwinding. We constructed two tri-helix wedge mutants and they indeed lost their RNA unwinding but not RNA binding or degrading activities. Our results suggest that the duplex RNA with an overhang is bound in the two RNA-binding channels in RNase R. The 3' overhang is threaded into the active site and the duplex RNA is unwound upon reaching the wedge region during RNA degradation. Thus, RNase R is a proficient enzyme, capable of concurrently binding, unwinding and degrading structured RNA in a highly processive manner during RNA decay.

Structural insights into RNA unwinding and degradation by RNase R.,Chu LY, Hsieh TJ, Golzarroshan B, Chen YP, Agrawal S, Yuan HS Nucleic Acids Res. 2017 Oct 3. doi: 10.1093/nar/gkx880. PMID:29036353<ref>PMID:29036353</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5xgu" style="background-color:#fffaf0;"></div>

==See Also==
*[[Ribonuclease 3D structures|Ribonuclease 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli DEC6A]]
[[Category: Large Structures]]
[[Category: Chu LY]]
[[Category: Hsieh TJ]]
[[Category: Yuan HS]]