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Publication Abstract from PubMed

In this study, we report the first atomic resolution structure of a stable G-hairpin formed by a natively occurring DNA sequence. An 11-nt long G-rich DNA oligonucleotide, 5'-d(GTGTGGGTGTG)-3', corresponding to the most abundant sequence motif in irregular telomeric DNA from Saccharomyces cerevisiae (yeast), is demonstrated to adopt a novel type of mixed parallel/antiparallel fold-back DNA structure, which is stabilized by dynamic G:G base pairs that transit between N1-carbonyl symmetric and N1-carbonyl, N7-amino base-pairing arrangements. Although the studied sequence first appears to possess a low capacity for base pairing, it forms a thermodynamically stable structure with a rather complex topology that includes a chain reversal arrangement of the backbone in the center of the continuous G-tract and 3'-to-5' stacking of the terminal residues. The structure reveals previously unknown principles of the folding of G-rich oligonucleotides that could be applied to the prediction of natural and/or the design of artificial recognition DNA elements. The structure also demonstrates that the folding landscapes of short DNA single strands is much more complex than previously assumed.

Structure of a Stable G-Hairpin.,Gajarsky M, Zivkovic ML, Stadlbauer P, Pagano B, Fiala R, Amato J, Tomaska L, Sponer J, Plavec J, Trantirek L J Am Chem Soc. 2017 Mar 2. doi: 10.1021/jacs.6b10786. PMID:28217994^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.