G-DNA: a twice-folded DNA structure adopted by single-stranded oligo(dG) and its implications for telomeres
| Autor: | A. A. Lipanov, R E Dickerson, M E Rikhirev, Edward I. Budowsky, O. I. Kovalsky, Igor G. Panyutin |
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| Rok vydání: | 1990 |
| Předmět: |
Models
Molecular Gel electrophoresis Multidisciplinary Molecular model Oligonucleotide Hydrogen bond Stereochemistry Stacking Hydrogen Bonding DNA Antiparallel (biochemistry) Chromosomes chemistry.chemical_compound Oligodeoxyribonucleotides chemistry Biochemistry Nucleic Acid Conformation Protein secondary structure Research Article |
| Zdroj: | Proceedings of the National Academy of Sciences. 87:867-870 |
| ISSN: | 1091-6490 0027-8424 |
| DOI: | 10.1073/pnas.87.3.867 |
| Popis: | Our dimethyl sulfate modification experiments suggest that (dG)n stretches within single-stranded DNA fragments, which represent the simplest model for telomeric sequences, adopt a complex intrastrand structure other than a simple hairpin. We present a molecular model for the DNA structure that conforms to dimethyl sulfate methylation data. The principal element of this G-DNA structure is a quadruple helix formed by pairwise antiparallel segments of the twice-folded (dG)n stretch. This quadruple core has two wide and two narrow grooves connected by three loop-shaped segments. The strong stacking interactions of the neighboring guanine tetrads and the large number of hydrogen bonds formed can be the primary reasons that such structures are favored over a common hairpin for long (dG)n stretches. Such compact structures may be formed from (dG)n stretches of telomeric sequences. |
| Databáze: | OpenAIRE |
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