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The parallel-stranded d(CGA) duplex is a highly predictable structural motif with two conformationally distinct strands.

ABSTRACT: DNA can adopt noncanonical structures that have important biological functions while also providing structural diversity for applications in nanotechnology. Here, the crystal structures of two oligonucleotides composed of d(CGA) triplet repeats in the parallel-stranded duplex form are described. The structure determination of four unique d(CGA)-based parallel-stranded duplexes across two crystal structures has allowed the structural parameters of d(CGA) triplets in the parallel-stranded duplex form to be characterized and established. These results show that d(CGA) units are highly uniform, but that each strand in the duplex is structurally unique and has a distinct role in accommodating structural asymmetries induced by the C-CH⁺ base pair.

SUBMITTER: Luteran EM

PROVIDER: S-EPMC8900823 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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The parallel-stranded d(CGA) duplex is a highly predictable structural motif with two conformationally distinct strands.

Luteran Emily M EM Paukstelis Paul J PJ

Acta crystallographica. Section D, Structural biology 20220218 Pt 3

DNA can adopt noncanonical structures that have important biological functions while also providing structural diversity for applications in nanotechnology. Here, the crystal structures of two oligonucleotides composed of d(CGA) triplet repeats in the parallel-stranded duplex form are described. The structure determination of four unique d(CGA)-based parallel-stranded duplexes across two crystal structures has allowed the structural parameters of d(CGA) triplets in the parallel-stranded duplex f ...[more]

PMID: 35234144

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The parallel-stranded d(CGA) duplex is a highly predictable structural motif with two conformationally distinct strands.

Publications

The parallel-stranded d(CGA) duplex is a highly predictable structural motif with two conformationally distinct strands.

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