1u64
From Proteopedia
(New page: 200px<br /><applet load="1u64" size="450" color="white" frame="true" align="right" spinBox="true" caption="1u64" /> '''The Solution Structure of d(G3T4G4)2'''<br /...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1u64.gif|left|200px]]<br /><applet load="1u64" size=" | + | [[Image:1u64.gif|left|200px]]<br /><applet load="1u64" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1u64" /> | caption="1u64" /> | ||
'''The Solution Structure of d(G3T4G4)2'''<br /> | '''The Solution Structure of d(G3T4G4)2'''<br /> | ||
==Overview== | ==Overview== | ||
| - | We have recently communicated that DNA oligonucleotide d(G(3)T(4)G(4)) | + | We have recently communicated that DNA oligonucleotide d(G(3)T(4)G(4)) forms a dimeric G-quadruplex in the presence of K(+) ions [J. Am. Chem. Soc.2003, 125, 7866-7871]. The high-resolution NMR structure of d(G(3)T(4)G(4))(2) G-quadruplex exhibits G-quadruplex core consisting of three stacked G-quartets. The two overhanging G3 and G11 residues are located at the opposite sides of the end G-quartets and are not involved in G-quartet formation. d(G(3)T(4)G(4))(2) G-quadruplex represents the first bimolecular G-quadruplex where end G-quartets are spanned by diagonal (T4-T7) as well as edge-type loops (T15-T18). Three of the G-rich strands are parallel while one is anti-parallel. The G12-G22 strand demonstrates a sharp reversal in strand direction between residues G19 and G20 that is accommodated with the leap over the middle G-quartet. The reversal in strand direction is achieved without any extra intervening residues. Here we furthermore examined the influence of different monovalent cations on the folding of d(G(3)T(4)G(4)). The resolved imino and aromatic proton resonances as well as (sequential) NOE connectivity patterns showed only minor differences in key intra- and interquartet NOE intensities in the presence of K(+), Na(+) and NH(4)(+) ions, which were consistent with subtle structural differences while retaining the same folding topology of d(G(3)T(4)G(4))(2) G-quadruplex. |
==About this Structure== | ==About this Structure== | ||
| - | 1U64 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http:// | + | 1U64 is a [http://en.wikipedia.org/wiki/Protein_complex 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=1U64 OCA]. |
==Reference== | ==Reference== | ||
| Line 19: | Line 19: | ||
[[Category: nmr]] | [[Category: nmr]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:21:01 2008'' |
Revision as of 13:21, 21 February 2008
|
The Solution Structure of d(G3T4G4)2
Overview
We have recently communicated that DNA oligonucleotide d(G(3)T(4)G(4)) forms a dimeric G-quadruplex in the presence of K(+) ions [J. Am. Chem. Soc.2003, 125, 7866-7871]. The high-resolution NMR structure of d(G(3)T(4)G(4))(2) G-quadruplex exhibits G-quadruplex core consisting of three stacked G-quartets. The two overhanging G3 and G11 residues are located at the opposite sides of the end G-quartets and are not involved in G-quartet formation. d(G(3)T(4)G(4))(2) G-quadruplex represents the first bimolecular G-quadruplex where end G-quartets are spanned by diagonal (T4-T7) as well as edge-type loops (T15-T18). Three of the G-rich strands are parallel while one is anti-parallel. The G12-G22 strand demonstrates a sharp reversal in strand direction between residues G19 and G20 that is accommodated with the leap over the middle G-quartet. The reversal in strand direction is achieved without any extra intervening residues. Here we furthermore examined the influence of different monovalent cations on the folding of d(G(3)T(4)G(4)). The resolved imino and aromatic proton resonances as well as (sequential) NOE connectivity patterns showed only minor differences in key intra- and interquartet NOE intensities in the presence of K(+), Na(+) and NH(4)(+) ions, which were consistent with subtle structural differences while retaining the same folding topology of d(G(3)T(4)G(4))(2) G-quadruplex.
About this Structure
1U64 is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
d(G3T4G4) forms unusual dimeric G-quadruplex structure with the same general fold in the presence of K+, Na+ or NH4+ ions., Sket P, Crnugelj M, Plavec J, Bioorg Med Chem. 2004 Nov 15;12(22):5735-44. PMID:15498650
Page seeded by OCA on Thu Feb 21 15:21:01 2008
