Specific recognition of human telomeric G-quadruplex DNA with small molecules and the conformational analysis by ESI mass spectrometry and circular dichroism spectropolarimetry.
Electrospray ionization mass spectrometry (ESI-MS) was utilized to investigate the binding affinity and stoichiometry of small molecules with human telomeric G-quadruplex DNA. The binding-affinity order obtained for the (AGGGTT)(4) quadruplex was: Tel01>ImImImbetaDp>>PyPyPygammaImImImbetaDp. The specific binding of Tel01 and PyPyPygammaImImImbetaDp in one system consisting of human telomeric G-quadruplex and duplex DNA was observed directly for the first time. This revealed that PyPyPygammaImImImbetaDp has a binding specificity for the duplex DNA, whereas Tel01 selectively recognizes the G-quadruplex DNA. Moreover, both ESI-MS and circular dichroism (CD) spectra indicated that Tel01 favored the formation and stabilization of the antiparallel G-quadruplex, and a structural transition of the (AGGGTT)(4) sequence from a coexistence of parallel and antiparallel G-quadruplexes to a parallel G-quadruplex induced by annealing.
Zhou
Jiang
J
Beijing National Laboratory for Molecular Sciences, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Yuan
Gu
G
D001483:Base Sequence; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D054856:G-Quadruplexes; D006147:Guanine / Q000737:chemistry*; D006576:Heterocyclic Compounds, 4 or More Rings / Q000737:chemistry*; D006801:Humans; D007093:Imidazoles / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D011758:Pyrroles / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D016615:Telomere / Q000737:chemistry*
D006576:Heterocyclic Compounds, 4 or More Rings; C521852:ImImImbetaDp compound; D007093:Imidazoles; C521853:PyPyPygammaImImImbetaDp compound; D011758:Pyrroles; C521851:Tel01 compound; D006147:Guanine; D004247:DNA