Quadruplex-forming properties of FRAXA (CGG) repeats interrupted by (AGG) triplets
Language English Country France Media print-electronic
Document type Journal Article, Research Support, Non-U.S. Gov't
PubMed
19028545
DOI
10.1016/j.biochi.2008.10.012
PII: S0300-9084(08)00308-8
Knihovny.cz E-resources
- MeSH
- Circular Dichroism MeSH
- DNA chemistry genetics MeSH
- Nucleic Acid Conformation MeSH
- Humans MeSH
- Fragile X Mental Retardation Protein genetics MeSH
- Base Sequence MeSH
- Fragile X Syndrome genetics MeSH
- Trinucleotide Repeats * MeSH
- Water chemistry MeSH
- Hydrogen Bonding MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- DNA MeSH
- Fragile X Mental Retardation Protein MeSH
- Water MeSH
The (CGG) repeats associated with X-chromosome fragility are generally believed to form quadruplexes. This notion has persisted although it had been shown that only very short (CGG)(n) sequences form quadruplexes and that this quadruplex formation occurs in conditions far from physiological. We have now studied, using CD and absorption spectroscopies, quadruplex formation of (CGG)(n) (n=4, 7, 8, or 16) and their analogs interrupted by (AGG) triplets under various solvent conditions. In healthy individuals, (AGG) triplets are interspersed throughout the (CGG) repeat regions and appear to hinder (CGG)(n) motif expansion. Here we show that (CGG) repeats do not form quadruplexes under physiological conditions in aqueous solution but, interestingly, quadruplexes are readily formed in water-ethanol solutions. The presence of (AGG) triplets markedly stabilized quadruplex formation. Quadruplexes may thus hinder rather than support (CGG)(n) motif expansion.
References provided by Crossref.org
Structures and stability of simple DNA repeats from bacteria
DNA and RNA quadruplex-binding proteins
