149d
From Proteopedia
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|PDB= 149d |SIZE=350|CAPTION= <scene name='initialview01'>149d</scene> | |PDB= 149d |SIZE=350|CAPTION= <scene name='initialview01'>149d</scene> | ||
|SITE= | |SITE= | ||
| - | |LIGAND= | + | |LIGAND= <scene name='pdbligand=DA:2'-DEOXYADENOSINE-5'-MONOPHOSPHATE'>DA</scene>, <scene name='pdbligand=DC:2'-DEOXYCYTIDINE-5'-MONOPHOSPHATE'>DC</scene>, <scene name='pdbligand=DG:2'-DEOXYGUANOSINE-5'-MONOPHOSPHATE'>DG</scene>, <scene name='pdbligand=DT:THYMIDINE-5'-MONOPHOSPHATE'>DT</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=149d FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=149d OCA], [http://www.ebi.ac.uk/pdbsum/149d PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=149d RCSB]</span> | ||
}} | }} | ||
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[[Category: triplex]] | [[Category: triplex]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 18:28:15 2008'' |
Revision as of 15:28, 30 March 2008
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| Ligands: | , , , | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
SOLUTION STRUCTURE OF A PYRIMIDINE(DOT)PURINE(DOT) PYRIMIDINE DNA TRIPLEX CONTAINING T(DOT)AT, C+(DOT)GC AND G(DOT)TA TRIPLES
Overview
BACKGROUND: Under certain conditions, homopyrimidine oligonucleotides can bind to complementary homopurine sequences in homopurine-homopyrimidine segments of duplex DNA to form triple helical structures. Besides having biological implications in vivo, this property has been exploited in molecular biology applications. This approach is limited by a lack of knowledge about the recognition by the third strand of pyrimidine residues in Watson-Crick base pairs. RESULTS: We have therefore determined the solution structure of a pyrimidine.purine.pyrimidine (Y.RY) DNA triple helix containing a guanine residue in the third strand which was postulated to specifically recognize a thymine residue in a Watson-Crick TA base pair. The structure was solved by combining NMR-derived restraints with molecular dynamics simulations conducted in the presence of explicit solvent and counter ions. The guanine of the G-TA triple is tilted out of the plane of its target TA base pair towards the 3'-direction, to avoid a steric clash with the thymine methyl group. This allows the guanine amino protons to participate in hydrogen bonds with separate carbonyls, forming one strong bond within the G-TA triple and a weak bond to an adjacent T.AT triple. Dramatic variations in helical twist around the guanine residue lead to a novel stacking interaction. At the global level, the Y.RY DNA triplex shares several structural features with the recently solved solution structure of the R.RY DNA triplex. CONCLUSIONS: The formation of a G.TA triple within an otherwise pyrimidine.purine.pyrimidine DNA triplex causes conformational realignments in and around the G.TA triple. These highlight new aspects of molecular recognition that could be useful in triplex-based approaches to inhibition of gene expression and site-specific cleavage of genomic DNA.
About this Structure
149D is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Solution structure of a pyrimidine.purine.pyrimidine DNA triplex containing T.AT, C+.GC and G.TA triples., Radhakrishnan I, Patel DJ, Structure. 1994 Jan 15;2(1):17-32. PMID:8075980
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Categories: Protein complex | Patel, D J. | Radhakrishnan, I. | Dna | Nmr | Triplex
