View source for 7mqh


==Bartonella henselae NrnC complexed with pAAAGG in the presence of Ca2+. D4 Symmetry.==
<StructureSection load='7mqh' size='340' side='right'caption='[[7mqh]], [[Resolution|resolution]] 3.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7mqh]] is a 16 chain structure with sequence from [https://en.wikipedia.org/wiki/Bartonella_henselae Bartonella henselae] and [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7MQH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7MQH FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.1&#8491;</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=7mqh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7mqh OCA], [https://pdbe.org/7mqh PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7mqh RCSB], [https://www.ebi.ac.uk/pdbsum/7mqh PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7mqh ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/X5MEI1_BARHN X5MEI1_BARHN] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
RNA degradation is fundamental for cellular homeostasis. The process is carried out by various classes of endolytic and exolytic enzymes that together degrade an RNA polymer to mono-ribonucleotides. Within the exoribonucleases, nano-RNases play a unique role as they act on the smallest breakdown products and hence catalyze the final steps in the process. We recently showed that oligoribonuclease (Orn) acts as a dedicated diribonucleotidase, defining the ultimate step in RNA degradation that is crucial for cellular fitness (Kim et al., 2019). Whether such a specific activity exists in organisms that lack Orn-type exoribonucleases remained unclear. Through quantitative structure-function analyses we show here that NrnC-type RNases share this narrow substrate length preference with Orn. Although NrnC employs similar structural features that distinguish these two classes as dinucleotidases from other exonucleases, the key determinants for dinucleotidase activity are realized through distinct structural scaffolds. The structures together with comparative genomic analyses of the phylogeny of DEDD-type exoribonucleases indicates convergent evolution as the mechanism of how dinucleotidase activity emerged repeatedly in various organisms. The evolutionary pressure to maintain dinucleotidase activity further underlines the important role these analogous proteins play for cell growth.

Structural characterization of NrnC identifies unifying features of dinucleotidases.,Lormand JD, Kim SK, Walters-Marrah GA, Brownfield BA, Fromme JC, Winkler WC, Goodson JR, Lee VT, Sondermann H Elife. 2021 Sep 17;10. pii: 70146. doi: 10.7554/eLife.70146. PMID:34533457<ref>PMID:34533457</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7mqh" style="background-color:#fffaf0;"></div>

==See Also==
*[[Ribonuclease 3D structures|Ribonuclease 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Bartonella henselae]]
[[Category: Large Structures]]
[[Category: Synthetic construct]]
[[Category: Brownfield B]]
[[Category: Fromme JC]]
[[Category: Lormand JD]]
[[Category: Sondermann H]]