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327d
From Proteopedia
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| - | [[Image:327d.gif|left|200px]] | + | [[Image:327d.gif|left|200px]] |
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| - | '''CRYSTAL STRUCTURES OF D(GM5CGM5CGCGCGC)''' | + | {{Structure |
| + | |PDB= 327d |SIZE=350|CAPTION= <scene name='initialview01'>327d</scene>, resolution 1.940Å | ||
| + | |SITE= | ||
| + | |LIGAND= | ||
| + | |ACTIVITY= | ||
| + | |GENE= | ||
| + | }} | ||
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| + | '''CRYSTAL STRUCTURES OF D(GM5CGM5CGCGCGC)''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 327D is a [ | + | 327D is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=327D OCA]. |
==Reference== | ==Reference== | ||
| - | Methylation of the Z-DNA decamer d(GC)5 potentiates the formation of A-DNA: crystal structure of d(Gm5CGm5CGCGCGC)., Tippin DB, Ramakrishnan B, Sundaralingam M, J Mol Biol. 1997 Jul 11;270(2):247-58. PMID:[http:// | + | Methylation of the Z-DNA decamer d(GC)5 potentiates the formation of A-DNA: crystal structure of d(Gm5CGm5CGCGCGC)., Tippin DB, Ramakrishnan B, Sundaralingam M, J Mol Biol. 1997 Jul 11;270(2):247-58. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/9236126 9236126] |
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Ramakrishnan, B.]] | [[Category: Ramakrishnan, B.]] | ||
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[[Category: modified]] | [[Category: modified]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 18:54:37 2008'' |
Revision as of 16:54, 20 March 2008
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| , resolution 1.940Å | |||||||
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| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURES OF D(GM5CGM5CGCGCGC)
Overview
It is well known that methylation of alternating Py x Pu sequences potentiates the formation of Z-DNA. However, we have now observed that methylation of the alternating Z-DNA oligomer d(GCGCGCGCGC), which starts with a 5'-purine, unexpectedly stabilizes the A-DNA conformation. The double methyl derivative d(Gm5CGm5CGCGCGC), which crystallizes as duplex A-DNA in the hexagonal space group P6(1)22, a = b = 39.33 A and c = 77.93 A with one strand per asymmetric unit and six duplexes in the unit cell, refined to an R factor of 19.1 for 204 DNA atoms and 43 solvent molecules. This is the first report of a DNA sequence crystallized in both right and left-handed conformations, allowing structural comparisons not previously possible and, more importantly, this is the first time that methylation has been shown to potentiate the formation of A-DNA from a sequence known to crystallize as Z-DNA. From this study, ten base-pairs appear to be the critical length in determining the handedness of d(GC)n-type sequences in the crystalline state. Because methylation of nuclear DNA is linked to a number of cellular processes, including transcriptional inactivation, this study has important implications for the role of A-DNA in methylated regions of genomic DNA and, thus, in the regulation of gene expression. In this context, the structure of d(Gm5Cm5CGCGCGC) will be compared with that of the alternating A-DNA decamer d(GCACGCGTGC) and the alternating Z-DNA decamer d(GCGCGCGCGC) and discussed in terms of the forces that govern the handedness of duplex DNA oligomers.
About this Structure
327D is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Methylation of the Z-DNA decamer d(GC)5 potentiates the formation of A-DNA: crystal structure of d(Gm5CGm5CGCGCGC)., Tippin DB, Ramakrishnan B, Sundaralingam M, J Mol Biol. 1997 Jul 11;270(2):247-58. PMID:9236126
Page seeded by OCA on Thu Mar 20 18:54:37 2008
