View source for 8gxc


==Crystal structure of NAD+ -II riboswitch in complex with NMN==
<StructureSection load='8gxc' size='340' side='right'caption='[[8gxc]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8gxc]] is a 7 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [https://en.wikipedia.org/wiki/Streptococcus_sp. Streptococcus sp.]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8GXC OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8GXC 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]] 2.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GTP:GUANOSINE-5-TRIPHOSPHATE'>GTP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NMN:BETA-NICOTINAMIDE+RIBOSE+MONOPHOSPHATE'>NMN</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=8gxc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8gxc OCA], [https://pdbe.org/8gxc PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8gxc RCSB], [https://www.ebi.ac.uk/pdbsum/8gxc PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8gxc ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/SNRPA_HUMAN SNRPA_HUMAN] Binds stem loop II of U1 snRNA. It is the first snRNP to interact with pre-mRNA. This interaction is required for the subsequent binding of U2 snRNP and the U4/U6/U5 tri-snRNP. In a snRNP-free form (SF-A) may be involved in coupled pre-mRNA splicing and polyadenylation process. Binds preferentially to the 5'-UGCAC-3' motif in vitro.<ref>PMID:9848648</ref> 
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== Publication Abstract from PubMed ==
Riboswitches are conserved non-coding domains in bacterial mRNA with gene regulation function that are essential for maintaining enzyme co-factor metabolism. Recently, the pnuC RNA motif was reported to selectively bind nicotinamide adenine dinucleotide (NAD+), defining a novel class of NAD+ riboswitches (NAD+-II) according to phylogenetic analysis. To reveal the three-dimensional architecture and the ligand-binding mode of this riboswitch, we solved the crystal structure of NAD+-II riboswitch in complex with NAD+. Strikingly and in contrast to class-I riboswitches that form a tight recognition pocket for the adenosine diphosphate (ADP) moiety of NAD+, the class-II riboswitches form a binding pocket for the nicotinamide mononucleotide (NMN) portion of NAD+ and display only unspecific interactions with the adenosine. We support this finding by an additional structure of the class-II RNA in complex with NMN alone. The structures define a novel RNA tertiary fold that was further confirmed by mutational analysis in combination with isothermal titration calorimetry (ITC), and 2-aminopurine-based fluorescence spectroscopic folding studies. Furthermore, we truncated the pnuC RNA motif to a short RNA helical scaffold with binding affinity comparable to the wild-type motif to allude to the potential of engineering the NAD+-II motif for biotechnological applications.

Structure-based investigations of the NAD+-II riboswitch.,Xu X, Egger M, Li C, Chen H, Micura R, Ren A Nucleic Acids Res. 2023 Jan 11;51(1):54-67. doi: 10.1093/nar/gkac1227. PMID:36610789<ref>PMID:36610789</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 8gxc" style="background-color:#fffaf0;"></div>

==See Also==
*[[Riboswitch 3D structures|Riboswitch 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Streptococcus sp]]
[[Category: Ren AM]]
[[Category: Xu XC]]