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1rvh
From Proteopedia
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|PDB= 1rvh |SIZE=350|CAPTION= <scene name='initialview01'>1rvh</scene> | |PDB= 1rvh |SIZE=350|CAPTION= <scene name='initialview01'>1rvh</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=[[1rvi|1RVI]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1rvh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1rvh OCA], [http://www.ebi.ac.uk/pdbsum/1rvh PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1rvh RCSB]</span> | ||
}} | }} | ||
| Line 28: | Line 31: | ||
[[Category: double helix]] | [[Category: double helix]] | ||
| - | ''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 23:33:33 2008'' |
Revision as of 20:33, 30 March 2008
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| Ligands: | , , , | ||||||
| Related: | 1RVI
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
SOLUTION STRUCTURE OF THE DNA DODECAMER GCAAAATTTTGC
Overview
DNA A-tracts have been defined as four or more consecutive A.T base pairs without a TpA step. When inserted in phase with the DNA helical repeat, bending is manifested macroscopically as anomalous migration on polyacrylamide gels, first observed >20 years ago. An unsolved conundrum is why DNA containing in-phase A-tract repeats of A(4)T(4) are bent, whereas T(4)A(4) is straight. We have determined the solution structures of the DNA duplexes formed by d(GCAAAATTTTGC) [A4T4] and d(CGTTTTAAAACG) [T4A4] with NH(4)(+) counterions by using NMR spectroscopy, including refinement with residual dipolar couplings. Analysis of the structures shows that the ApT step has a large negative roll, resulting in a local bend toward the minor groove, whereas the TpA step has a positive roll and locally bends toward the major groove. For A4T4, this bend is nearly in phase with bends at the two A-tract junctions, resulting in an overall bend toward the minor groove of the A-tract, whereas for T4A4, the bends oppose each other, resulting in a relatively straight helix. NMR-based structural modeling of d(CAAAATTTTG)(15) and d(GTTTTAAAAC)(15) reveals that the former forms a left-handed superhelix with a diameter of approximately 110 A and pitch of 80 A, similar to DNA in the nucleosome, whereas the latter has a gentle writhe with a pitch of >250 A and diameter of approximately 50 A. Results of gel electrophoretic mobility studies are consistent with the higher-order structure of the DNA and furthermore depend on the nature of the monovalent cation present in the running buffer.
About this Structure
1RVH is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
DNA A-tract bending in three dimensions: solving the dA4T4 vs. dT4A4 conundrum., Stefl R, Wu H, Ravindranathan S, Sklenar V, Feigon J, Proc Natl Acad Sci U S A. 2004 Feb 3;101(5):1177-82. Epub 2004 Jan 22. PMID:14739342
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