View source for 7ech


==Crystal Structure of d(G4C2)2-K in F222 space group==
<StructureSection load='7ech' size='340' side='right'caption='[[7ech]], [[Resolution|resolution]] 2.38&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7ech]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7ECH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7ECH 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]] 2.38&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=K:POTASSIUM+ION'>K</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=7ech FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7ech OCA], [https://pdbe.org/7ech PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7ech RCSB], [https://www.ebi.ac.uk/pdbsum/7ech PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7ech ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The hexanucleotide repeat expansion, GGGGCC (G4C2), within the first intron of the C9orf72 gene is known to be the most common genetic cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The G4C2 repeat expansions, either DNA or RNA, are able to form G-quadruplexes which induce toxicity leading to ALS/FTD. Herein, we report a novel crystal structure of d(G4C2)2 that self-associates to form an eight-layer parallel tetrameric G-quadruplex. Two d(G4C2)2 associate together as a parallel dimeric G-quadruplex which folds into a tetramer via 5'-to-5' arrangements. Each dimer consists of four G-tetrads connected by two CC propeller loops. Especially, the 3'-end cytosines protrude out and form C.C+*C.C+/ C.C*C.C+ quadruple base pair or C*C.C+ triple base pair stacking on the dimeric block. Our work sheds light on the G-quadruplexes adopted by d(G4C2) and yields the invaluable structural details for the development of small molecules to tackle neurodegenerative diseases, ALS and FTD.

Crystal structure of parallel G-quadruplex formed by the two-repeat ALS- and FTD-related GGGGCC sequence.,Geng Y, Liu C, Cai Q, Luo Z, Miao H, Shi X, Xu N, Fung CP, Choy TT, Yan B, Li N, Qian P, Zhou B, Zhu G Nucleic Acids Res. 2021 May 28. pii: 6287844. doi: 10.1093/nar/gkab302. PMID:34048588<ref>PMID:34048588</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7ech" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Cai Q]]
[[Category: Geng Y]]
[[Category: Liu C]]
[[Category: Luo Z]]
[[Category: Zhu G]]