1oz8
From Proteopedia
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Intramolecular higher-order packing of parallel quadruplexes comprising a G:G:G:G tetrad and a G(:A):G(:A):G(:A):G heptad of GGA triplet repeat DNA
Overview
GGA triplet repeats are widely dispersed throughout eukaryotic genomes and, are frequently located within biologically important regions such as gene, regulatory regions and recombination hot spot sites. We determined the, structure of d(GGA)4 (12-mer) under physiological conditions and founded, the formation of an intramolecular parallel quadruplex for the first time., Later, a similar architecture to that of the intramolecular parallel, quadruplex was found for a telomere DNA in the crystalline state. Here, we, have determined the structure of d(GGA)8 (24-mer) under physiological, conditions. Two intramolecular parallel quadruplexes comprising a G:G:G:G, tetrad and a G(:A):G(:A):G(:A):G heptad are formed in d(GGA)8. These, quadruplexes are packed in a tail-to-tail manner. This is the first, demonstration of the intramolecular higher order packing of quadruplexes, at atomic resolution. K+ ions, but not Na+ ones, are critically required, for the formation of this unique structure. The elucidated structure, suggests the mechanisms underlying the biological events related to the, GGA triplet repeat. Furthermore, in the light of the structure, the mode, of the higher order packing of the telomere DNA is discussed.
About this Structure
1OZ8 is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Intramolecular higher order packing of parallel quadruplexes comprising a G:G:G:G tetrad and a G(:A):G(:A):G(:A):G heptad of GGA triplet repeat DNA., Matsugami A, Okuizumi T, Uesugi S, Katahira M, J Biol Chem. 2003 Jul 25;278(30):28147-53. Epub 2003 May 14. PMID:12748183
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