6KFI

NMR solution structure of the 1:1 complex of Tel26 G-quadruplex and a tripodal cationic fluorescent probe NBTE

Summary for 6KFI

• Entry DOI: 10.2210/pdb6kfi/pdb
• NMR Information: BMRB: 36267
• Descriptor: G-quadruplex DNA (26-MER), 4,4',4''-(nitrilotris(benzene-4,1-diyl))tris(1-ethylpyridin-1-ium) iodide (2 entities in total)
• Functional Keywords: g-quadruplex dna, probe, dna
• Biological source: Homo sapiens
• Total number of polymer chains: 1
• Total formula weight: 8800.08

Authors

Liu, W.,Liu, L.Y.,Mao, Z.W. (deposition date: 2019-07-07, release date: 2020-07-08, Last modification date: 2024-05-01)

Primary citation

Liu, L.Y.,Liu, W.,Wang, K.N.,Zhu, B.C.,Xia, X.Y.,Ji, L.N.,Mao, Z.W.
Quantitative Detection of G-Quadruplex DNA in Live Cells Based on Photon Counts and Complex Structure Discrimination.
Angew.Chem.Int.Ed.Engl., 59:9719-9726, 2020

PubMed Abstract: G-quadruplex DNA show structural polymorphism, leading to challenges in the use of selective recognition probes for the accurate detection of G-quadruplexes in vivo. Herein, we present a tripodal cationic fluorescent probe, NBTE, which showed distinguishable fluorescence lifetime responses between G-quadruplexes and other DNA topologies, and fluorescence quantum yield (Φ ) enhancement upon G-quadruplex binding. We determined two NBTE-G-quadruplex complex structures with high Φ values by NMR spectroscopy. The structures indicated NBTE interacted with G-quadruplexes using three arms through π-π stacking, differing from that with duplex DNA using two arms, which rationalized the higher Φ values and lifetime response of NBTE upon G-quadruplex binding. Based on photon counts of FLIM, we detected the percentage of G-quadruplex DNA in live cells with NBTE and found G-quadruplex DNA content in cancer cells is 4-fold that in normal cells, suggesting the potential applications of this probe in cancer cell detection.

PubMed: 32173994
DOI: 10.1002/anie.202002422

Experimental method

SOLUTION NMR