Tetraplex formation by the progressive myoclonus epilepsy type-1 repeat: implications for instability in the repeat expansion diseases.
The repeat expansion diseases are a group of genetic disorders resulting from an increase in size or expansion of a specific array of tandem repeats. It has been suggested that DNA secondary structures are responsible for this expansion. If this is so, we would expect that all unstable repeats should form such structures. We show here that the unstable repeat that causes progressive myoclonus epilepsy type-1 (EPM1), like the repeats associated with other diseases in this category, forms a variety of secondary structures. However, EPM1 is unique in that tetraplexes are the only structures likely to form in long unpaired repeat tracts under physiological conditions.
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Section on Genomic Structure and Function, Laboratory of Molecular and Cellular Biology, National Institute of Diabetes and Kidney Diseases, Building 8, Room 202, National Institutes of Health, 8 CENTER DR MSC 0830, Bethesda, MD 20892-0830, USA.
Usdin
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D000143:Acids / Q000737:chemistry; D002942:Circular Dichroism; D003597:Cytosine Nucleotides / Q000737:chemistry / Q000378:metabolism; D004247:DNA / Q000737:chemistry*; D004047:Diethyl Pyrocarbonate / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D054856:G-Quadruplexes; D006151:Guanosine / Q000737:chemistry / Q000378:metabolism; D006860:Hydrogen Bonding; D020191:Myoclonic Epilepsies, Progressive / Q000235:genetics*; D009690:Nucleic Acid Conformation / Q000187:drug effects; D011189:Potassium Chloride / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D013463:Sulfuric Acid Esters / Q000494:pharmacology; D013696:Temperature; D019680:Trinucleotide Repeat Expansion / Q000187:drug effects / Q000235:genetics*; D020194:Unverricht-Lundborg Syndrome / Q000235:genetics
D000143:Acids; D003597:Cytosine Nucleotides; D013463:Sulfuric Acid Esters; D006151:Guanosine; D011189:Potassium Chloride; D004247:DNA; C007482:dimethyl sulfate; D004047:Diethyl Pyrocarbonate