1emq
From Proteopedia
(New page: 200px<br /><applet load="1emq" size="450" color="white" frame="true" align="right" spinBox="true" caption="1emq" /> '''NMR OBSERVATION OF T-TETRADS IN A PARALLEL S...) |
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| - | [[Image:1emq.gif|left|200px]]<br /><applet load="1emq" size=" | + | [[Image:1emq.gif|left|200px]]<br /><applet load="1emq" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1emq" /> | caption="1emq" /> | ||
'''NMR OBSERVATION OF T-TETRADS IN A PARALLEL STRANDED DNA QUADRUPLEX FORMED BY SACCHAROMYCES CEREVISIAE TELOMERE REPEATS'''<br /> | '''NMR OBSERVATION OF T-TETRADS IN A PARALLEL STRANDED DNA QUADRUPLEX FORMED BY SACCHAROMYCES CEREVISIAE TELOMERE REPEATS'''<br /> | ||
==Overview== | ==Overview== | ||
| - | We report here the NMR structure of the DNA sequence d-TGGTGGC containing | + | We report here the NMR structure of the DNA sequence d-TGGTGGC containing two repeats of Saccharomyces cerevisiae telomere DNA which is unique in that it has a single thymine in the repeat sequence and the number of Gs can vary from one to three. The structure is a novel quadruplex incor-porating T-tetrads formed by symmetrical pairing of four Ts via O4-H3 H-bonds in a plane. This is in contrast to the previous results on other telomeric sequences which contained more than one T in the repeat sequences and they were seen mostly in the flexible regions of the structures. We observed that the T4-tetrad was nicely accommodated in the center of the G-quadruplex, but it caused a small underwinding of the right handed helix. The T tetrad stacked well on the adjacent G3-tetrad, but poorly on the G5 tetrad. Likewise, T1 also formed a stable T-tetrad at the 5' end of the quadruplex. To our knowledge, this is the first report of T-tetrad formation in DNA structures. These observations are of significance from the points of view of both structural diversity and specific recognitions. |
==About this Structure== | ==About this Structure== | ||
| - | 1EMQ 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:// | + | 1EMQ 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=1EMQ OCA]. |
==Reference== | ==Reference== | ||
NMR observation of T-tetrads in a parallel stranded DNA quadruplex formed by Saccharomyces cerevisiae telomere repeats., Patel PK, Hosur RV, Nucleic Acids Res. 1999 Jun 15;27(12):2457-64. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=10352174 10352174] | NMR observation of T-tetrads in a parallel stranded DNA quadruplex formed by Saccharomyces cerevisiae telomere repeats., Patel PK, Hosur RV, Nucleic Acids Res. 1999 Jun 15;27(12):2457-64. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=10352174 10352174] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Hosur, R | + | [[Category: Hosur, R V.]] |
| - | [[Category: Patel, P | + | [[Category: Patel, P K.]] |
[[Category: g-quadruplex]] | [[Category: g-quadruplex]] | ||
[[Category: saccharomyces cerevisiae]] | [[Category: saccharomyces cerevisiae]] | ||
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[[Category: yeast]] | [[Category: yeast]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:29:23 2008'' |
Revision as of 10:29, 21 February 2008
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NMR OBSERVATION OF T-TETRADS IN A PARALLEL STRANDED DNA QUADRUPLEX FORMED BY SACCHAROMYCES CEREVISIAE TELOMERE REPEATS
Overview
We report here the NMR structure of the DNA sequence d-TGGTGGC containing two repeats of Saccharomyces cerevisiae telomere DNA which is unique in that it has a single thymine in the repeat sequence and the number of Gs can vary from one to three. The structure is a novel quadruplex incor-porating T-tetrads formed by symmetrical pairing of four Ts via O4-H3 H-bonds in a plane. This is in contrast to the previous results on other telomeric sequences which contained more than one T in the repeat sequences and they were seen mostly in the flexible regions of the structures. We observed that the T4-tetrad was nicely accommodated in the center of the G-quadruplex, but it caused a small underwinding of the right handed helix. The T tetrad stacked well on the adjacent G3-tetrad, but poorly on the G5 tetrad. Likewise, T1 also formed a stable T-tetrad at the 5' end of the quadruplex. To our knowledge, this is the first report of T-tetrad formation in DNA structures. These observations are of significance from the points of view of both structural diversity and specific recognitions.
About this Structure
1EMQ is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
NMR observation of T-tetrads in a parallel stranded DNA quadruplex formed by Saccharomyces cerevisiae telomere repeats., Patel PK, Hosur RV, Nucleic Acids Res. 1999 Jun 15;27(12):2457-64. PMID:10352174
Page seeded by OCA on Thu Feb 21 12:29:23 2008
