View source for 8po8


==Structure of Escherichia coli HrpA in complex with ADP and oligonucleotide poly(dC)11 forming an i-motif==
<StructureSection load='8po8' size='340' side='right'caption='[[8po8]], [[Resolution|resolution]] 2.52&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8po8]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] and [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8PO8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8PO8 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]] 2.52&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ADP:ADENOSINE-5-DIPHOSPHATE'>ADP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=SIN:SUCCINIC+ACID'>SIN</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=8po8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8po8 OCA], [https://pdbe.org/8po8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8po8 RCSB], [https://www.ebi.ac.uk/pdbsum/8po8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8po8 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/HRPA_ECOLI HRPA_ECOLI] Not yet known.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
RNA helicases function as versatile enzymes primarily responsible for remodeling RNA secondary structures and organizing ribonucleoprotein complexes. In our study, we conducted a systematic analysis of the helicase-related activities of Escherichia coli HrpA and presented the structures of both its apo form and its complex bound with both conventional and non-canonical DNAs. Our findings reveal that HrpA exhibits NTP hydrolysis activity and binds to ssDNA and ssRNA in distinct sequence-dependent manners. While the helicase core plays an essential role in unwinding RNA/RNA and RNA/DNA duplexes, the N-terminal extension in HrpA, consisting of three helices referred to as the APHB domain, is crucial for ssDNA binding and RNA/DNA duplex unwinding. Importantly, the APHB domain is implicated in binding to non-canonical DNA structures such as G-quadruplex and i-motif, and this report presents the first solved i-motif-helicase complex. This research not only provides comprehensive insights into the multifaceted roles of HrpA as an RNA helicase but also establishes a foundation for further investigations into the recognition and functional implications of i-motif DNA structures in various biological processes.

Structural insights into the N-terminal APHB domain of HrpA: mediating canonical and i-motif recognition.,Xin BG, Huang LY, Yuan LG, Liu NN, Li HH, Ai X, Lei DS, Hou XM, Rety S, Xi XG Nucleic Acids Res. 2024 Apr 12;52(6):3406-3418. doi: 10.1093/nar/gkae138. PMID:38412313<ref>PMID:38412313</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8po8" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Escherichia coli K-12]]
[[Category: Large Structures]]
[[Category: Ai X]]
[[Category: Li HH]]
[[Category: Liu NN]]
[[Category: Rety S]]
[[Category: Xi XG]]
[[Category: Xie SM]]
[[Category: Xin BG]]
[[Category: Yuan LG]]
[[Category: Zhang LL]]