Evaluation of the Stability of DNA i‐Motifs in the Nuclei of Living Mammalian Cells

• Published in: Angewandte Chemie 2018-02, Vol.130 (8), p.2187-2191
• Main Authors: Dzatko, Simon, Krafcikova, Michaela, Hänsel‐Hertsch, Robert, Fessl, Tomas, Fiala, Radovan, Loja, Tomas, Krafcik, Daniel, Mergny, Jean‐Louis, Foldynova‐Trantirkova, Silvie, Trantirek, Lukas
• Format: Article
• Language: English
• Subjects: Biosensors; Cellular structure; Chemistry; Deoxyribonucleic acid; DNA; Gene expression; Gene regulation; Gene sequencing; Genomes; i-Motive; Magnetic resonance spectroscopy; Mammalian cells; NMR; NMR spectroscopy; NMR-Spektroskopie in Zellen; Nuclear magnetic resonance; Nuclei; Nuclei (cytology); Stability analysis; Strukturbiologie; Transcription
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.201712284

C‐rich DNA has the capacity to form a tetra‐stranded structure known as an i‐motif. The i‐motifs within genomic DNA have been proposed to contribute to the regulation of DNA transcription. However, direct experimental evidence for the existence of these structures in vivo has been missing. Whether i‐motif structures form in complex environment of living cells is not currently known. Herein, using state‐of‐the‐art in‐cell NMR spectroscopy, we evaluate the stabilities of i‐motif structures in the complex cellular environment. We show that i‐motifs formed from naturally occurring C‐rich sequences in the human genome are stable and persist in the nuclei of living human cells. Our data show that i‐motif stabilities in vivo are generally distinct from those in vitro. Our results are the first to interlink the stability of DNA i‐motifs in vitro with their stability in vivo and provide essential information for the design and development of i‐motif‐based DNA biosensors for intracellular applications. DNA‐Live‐Übertragung: Die Stabilität von DNA‐i‐Motiven, gebildet aus natürlichen C‐reichen Sequenzen im Humangenom, wurde in den Zellkernen lebender menschlicher Zellen studiert. Ein reversibler Faltungs‐Entfaltungs‐Zyklus wurde nachgewiesen, und die (thermodynamische) Stabilität der DNA‐i‐Motive in vitro und in vivo wurde in Zusammenhang gesetzt.