The RNA Institute, University at Albany, State University of New York, Albany, NY, USA.
Department of Biological Sciences, University at Albany, State University of New York, Albany, NY, USA.
Nat Commun. 2024 Aug 6;15(1):6636. doi: 10.1038/s41467-024-50348-3.
Synthetic DNA motifs form the basis of nucleic acid nanotechnology. The biochemical and biophysical properties of these motifs determine their applications. Here, we present a detailed characterization of switchback DNA, a globally left-handed structure composed of two parallel DNA strands. Compared to a conventional duplex, switchback DNA shows lower thermodynamic stability and requires higher magnesium concentration for assembly but exhibits enhanced biostability against some nucleases. Strand competition and strand displacement experiments show that component sequences have an absolute preference for duplex complements instead of their switchback partners. Further, we hypothesize a potential role for switchback DNA as an alternate structure in sequences containing short tandem repeats. Together with small molecule binding experiments and cell studies, our results open new avenues for switchback DNA in biology and nanotechnology.
合成 DNA 基序构成了核酸纳米技术的基础。这些基序的生化和物理特性决定了它们的应用。在这里，我们详细描述了折返 DNA，这是一种由两条平行 DNA 链组成的全局左手结构。与传统的双链体相比，折返 DNA 的热力学稳定性较低，组装所需的镁离子浓度较高，但对某些核酸酶具有增强的生物稳定性。链竞争和链置换实验表明，组成序列绝对偏爱双链体互补序列，而不是其折返体配对物。此外，我们假设折返 DNA 在含有短串联重复序列的序列中可能作为替代结构发挥作用。结合小分子结合实验和细胞研究，我们的结果为折返 DNA 在生物学和纳米技术中的应用开辟了新途径。
