139d: Difference between revisions

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-[[Image:139d.png|left|200px]]
+==SOLUTION STRUCTURE OF A PARALLEL-STRANDED G-QUADRUPLEX DNA==
+<StructureSection load='139d' size='340' side='right' caption='[[139d]], [[NMR_Ensembles_of_Models | 4 NMR models]]' scene=''>
+== Structural highlights ==
+<table><tr><td colspan='2'>[[139d]] is a 4 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=139D OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=139D FirstGlance]. <br>
+</td></tr><tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=139d FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=139d OCA], [http://www.rcsb.org/pdb/explore.do?structureId=139d RCSB], [http://www.ebi.ac.uk/pdbsum/139d PDBsum]</span></td></tr>
+<table>
+<div style="background-color:#fffaf0;">
+== Publication Abstract from PubMed ==
+This paper reports on the solution structure of a parallel-stranded G-quadruplex formed by the Tetrahymena telomeric sequence d(T-T-G-G-G-G-T) whose NMR parameters in potassium cation containing solution were previously published from our laboratory. The structure was determined by combining a quantitative analysis of the NMR data with molecular dynamics calculations including relaxation matrix refinement. The combined NMR-computational approach yielded a set of seven distance-refined structures with pairwise RMSDs ranging from 0.66 to 1.30 A for the central G-G-G-G tetranucleotide segment. Four of the seven structures were refined further using complete relaxation-matrix calculations to yield solution structures with pairwise RMSDs ranging from 0.64 to 1.04 A for the same tetranucleotide segment. The R-factors also decreased on proceeding from the distance-refined to relaxation matrix-refined structures. The four strands of the G-quadruplex are aligned in parallel and are related by a 4-fold symmetry axis coincident with the helix axis. Individual guanines from each strand form planar G.G.G.G tetrad arrangements with each tetrad stabilized by eight hydrogen bonds involving the Watson-Crick and Hoogsteen edges of the guanine bases. All guanines adopt anti glycosidic torsion angles and S type sugar puckers in this right-handed parallel-stranded G-quadruplex structure. The four G.G.G.G tetrad planes stack on each other with minimal overlap of adjacent guanine base planes within individual strands. The thymine residues are under-defined in the solution structure of the d(T-T-G-G-G-G-T) G-quadruplex and sample amongst multiple conformations in solution.
-{{STRUCTURE_139d|  PDB=139d  |  SCENE=  }}
+Solution structure of a parallel-stranded G-quadruplex DNA.,Wang Y, Patel DJ J Mol Biol. 1993 Dec 20;234(4):1171-83. PMID:8263919<ref>PMID:8263919</ref>
-===SOLUTION STRUCTURE OF A PARALLEL-STRANDED G-QUADRUPLEX DNA===
+From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
+</div>
-{{ABSTRACT_PUBMED_8263919}}
+== References ==
+<references/>
-==About this Structure==
+__TOC__
-[[139d]] is a 4 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=139D OCA].
+</StructureSection>
-==Reference==
-<ref group="xtra">PMID:008263919</ref><references group="xtra"/>
 [[Category: Patel, D J.]]
 [[Category: Wang, Y.]]