title: Photodependent Melting of Unmodified DNA Using a Photosensitive Intercalator: A New and Generic Tool for Photoreversible Assembly of DNA Nanostructures at Constant Temperature.
abstract: External control of DNA melting and hybridization, a key step in bio- and DNA nanotechnology, is commonly achieved with temperature. The use of light to direct this process is a challenging alternative, which has been only possible with a DNA modification, such as covalent grafting or mismatch introduction, so far. Here we describe the first photocontrol of DNA melting that relies on the addition of a molecule that noncovalently interacts with unmodified DNA and affects its melting properties in a photoreversible and highly robust manner, without any prerequisite in the length or sequence of the target DNA molecule. We synthesize azobenzene-containing guanidinium derivatives and show that a bivalent molecule with a conformation-dependent binding mode, AzoDiGua, strongly increases the melting temperature (Tm) of DNA under dark conditions because its trans isomer intercalates in the DNA double helix. Upon UV irradiation at 365 nm, the trans-cis isomerization induced the ejection of AzoDiGua from the intercalation binding sites, resulting in a decrease in Tm up to 18 °C. This illumination-dependent Tm shift is observed on many types of DNA, from self-complementary single-stranded or double-stranded oligonucleotides to long genomic duplex DNA molecules. Finally, we show that simply adding AzoDiGua allows us to photoreversibly control the assembly/disassembly of a DNA nanostructure at constant temperature, as demonstrated here with a self-hybridized DNA hairpin. We anticipate that this strategy will be the key ingredient in a new and generic way of placing DNA-based bio- and nanotechnologies under dynamic control by light.
authors.affiliation: Department of Chemistry, Ecole Normale Supérieure-PSL Research University , 24 rue Lhomond, 75005 Paris, France.|Sorbonne Universités, UPMC Univ Paris 06, PASTEUR, 75005 Paris, France.|CNRS, UMR 8640 PASTEUR, 75005 Paris, France.
authors.forename: Anna
authors.initials: A
authors.lastname: Bergen
authors.affiliation: Department of Chemistry, Ecole Normale Supérieure-PSL Research University , 24 rue Lhomond, 75005 Paris, France.|Sorbonne Universités, UPMC Univ Paris 06, PASTEUR, 75005 Paris, France.|CNRS, UMR 8640 PASTEUR, 75005 Paris, France.
authors.forename: Sergii
authors.initials: S
authors.lastname: Rudiuk
authors.affiliation: Department of Chemistry, Ecole Normale Supérieure-PSL Research University , 24 rue Lhomond, 75005 Paris, France.|Sorbonne Universités, UPMC Univ Paris 06, PASTEUR, 75005 Paris, France.|CNRS, UMR 8640 PASTEUR, 75005 Paris, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Morel
authors.affiliation: Department of Chemistry, Ecole Normale Supérieure-PSL Research University , 24 rue Lhomond, 75005 Paris, France.|Sorbonne Universités, UPMC Univ Paris 06, PASTEUR, 75005 Paris, France.|CNRS, UMR 8640 PASTEUR, 75005 Paris, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Le Saux
authors.affiliation: Department of Chemistry-Biology, University of Siegen , Adolf-Reichwein-Str. 2, 57068 Siegen, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Ihmels
authors.affiliation: Department of Chemistry, Ecole Normale Supérieure-PSL Research University , 24 rue Lhomond, 75005 Paris, France.|Sorbonne Universités, UPMC Univ Paris 06, PASTEUR, 75005 Paris, France.|CNRS, UMR 8640 PASTEUR, 75005 Paris, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Baigl
mesh_terms: D004247:DNA / Q000737:chemistry*; D007364:Intercalating Agents / Q000737:chemistry; D008027:Light; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology; D009690:Nucleic Acid Conformation; D010777:Photochemistry; D013696:Temperature; D013816:Thermodynamics; D014466:Ultraviolet Rays
chemical_list: D007364:Intercalating Agents; D004247:DNA
keywords: DNA hybridization; DNA nanotechnology; azobenzene; intercalator; photocontrol