1384953-16-5Relevant academic research and scientific papers
Direct quantification of loop interaction and π-π Stacking for G-quadruplex stability at the submolecular level
Ghimire, Chiran,Park, Soyoung,Iida, Keisuke,Yangyuoru, Philip,Otomo, Haruka,Yu, Zhongbo,Nagasawa, Kazuo,Sugiyama, Hiroshi,Mao, Hanbin
, p. 15537 - 15544 (2014)
The well-demonstrated biological functions of DNA G-quadruplex inside cells call for small molecules that can modulate these activities by interacting with G-quadruplexes. However, the paucity of the understanding of the G-quadruplex stability contributed
Binding of a Telomestatin Derivative Changes the Mechanical Anisotropy of a Human Telomeric G-Quadruplex
Jonchhe, Sagun,Ghimire, Chiran,Cui, Yunxi,Sasaki, Shogo,McCool, Mason,Park, Soyoung,Iida, Keisuke,Nagasawa, Kazuo,Sugiyama, Hiroshi,Mao, Hanbin
, p. 877 - 881 (2019)
Mechanical anisotropy is an essential property for biomolecules to assume structural and functional roles in mechanobiology. However, there is insufficient information on the mechanical anisotropy of ligand–biomolecule complexes. Herein, we investigated the mechanical property of individual human telomeric G-quadruplexes bound to telomestatin, using optical tweezers. Stacking of the ligand to the G-tetrad planes changes the conformation of the G-quadruplex, which resembles a balloon squeezed in certain directions. Such a squeezed balloon effect strengthens the G-tetrad planes, but dislocates and weakens the loops in the G-quadruplex upon ligand binding. These dynamic interactions indicate that the binding between the ligand and G-quadruplex follows the induced-fit model. We anticipate that the altered mechanical anisotropy of the ligand–G-quadruplex complex can add additional level of regulations on the motor enzymes that process DNA or RNA molecules.
Alkynyl phosphonate DNA: A versatile click able backbone for DNA-based biological applications
Krishna, Heera,Caruthers, Marvin H.
experimental part, p. 11618 - 11631 (2012/09/05)
Major hurdles associated with DNA-based biological applications include, among others, targeted cell delivery, undesirable nonspecific effects, toxicity associated with various analogues or the reagents used to deliver oligonucleotides to cells, and stability toward intracellular enzymes. Although a plethora of diverse analogues have been investigated, a versatile methodology that can systematically address these challenges has not been developed. In this contribution, we present a new, Clickable, and versatile chemistry that can be used to rapidly introduce diverse functionality for studying these various problems. As a demonstration of the approach, we synthesized the core analogue, which is useful for introducing additional functionality, the triazolylphosphonate, and present preliminary data on its biological properties. We have developed a new phosphoramidite synthon-the alkynyl phosphinoamidite, which is compatible with conventional solid-phase oligonucleotide synthesis. Postsynthesis, the alkynylphosphonate can be functionalized via Click chemistry to generate the 1,2,3-triazolyl or substituted 1,2,3-triazolyl phosphonate-2′-deoxyribonucleotide internucleotide linkage. This manuscript describes the automated, solid-phase synthesis of mixed backbone oligodeoxyribonucleotides (ODNs) having 1,2,3-triazolylphosphonate (TP) as well as phosphate or thiophosphate internucleotide linkages and also 2′-OMe ribonucleotides and locked nucleic acids (LNAs) at selected sites. Nuclease stability assays demonstrate that the TP linkage is highly resistant toward 5′- and 3′-exonucleases, whereas melting studies indicate a slight destabilization when a TP-modified ODN is hybridized to its complementary RNA. A fluorescently labeled 16-mer ODN modified with two TP linkages shows efficient cellular uptake during passive transfection. Of particular interest, the subcellular distribution of TP-modified ODNs is highly dependent on cell type; a significant nuclear uptake is observed in HeLa cells, whereas diffuse cytoplasmic fluorescence is found in the WM-239A cell line. Cytoplasmic distribution is also present in human neuroblastoma cells (SK-N-F1), but Jurkat cells show both diffuse and punctate cytoplasmic uptake. Our results demonstrate that triazolylphosphonate ODNs are versatile additions to the oligonucleotide chemist's toolbox relative to designing new biological research reagents.
