title: Coumarin-Induced DNA Ligation, Rearrangement to DNA Interstrand Crosslinks, and Photorelease of Coumarin Moiety.
abstract: Coumarin moieties react with thymine and cytosine in DNA by photoinduced [2+2] cycloaddition, which allows quantitative DNA interstrand crosslink (ICL) formation. Here, we report the application of coumarin analogues for DNA photoligation and the rearrangement of coumarin-induced ligation to ICL products. Both DNA sequences and the linker units at position 4 of the coumarin moieties affected coumarin-induced DNA photoligation. A flexible linker unit favored DNA ICL formation but led to inefficient photoligation, whereas coumarins without linker units greatly increased DNA photoligation efficiency. DNA photoligation induced by the coumarin moiety was photoswitchable. Ligation products were formed between coumarin and dT or dC upon 350 nm irradiation but reverted to the original single-stranded oligodeoxyribonucleotides (ODNs) upon 254 nm irradiation. Rearrangement of ligated ODNs into ICL products occurred during the switchable (350 nm/254 nm) processes. Additionally, photoinduced cleavage of coumarin 3 occurred with dC-3 cycloadducts upon 254 nm irradiation, which was confirmed by mass spectrometry analysis.
authors: Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210 N. Cramer St., Milwaukee, WI, 53211, USA.
authors: Huabing
authors: H
authors: Sun
authors: Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210 N. Cramer St., Milwaukee, WI, 53211, USA.
authors: Heli
authors: H
authors: Fan
authors: Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210 N. Cramer St., Milwaukee, WI, 53211, USA.
authors: Hyeyoung
authors: H
authors: Eom
authors: Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210 N. Cramer St., Milwaukee, WI, 53211, USA. pengx@uwm.edu.
authors: Xiaohua
authors: X
authors: Peng
mesh_terms: D003374:Coumarins / Q000737:chemistry* / Q000494:pharmacology*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D004247:DNA / Q000737:chemistry* / Q000187:drug effects*; D006801:Humans; D015394:Molecular Structure; D055668:Photochemical Processes
chemical_list: D003374:Coumarins; D003432:Cross-Linking Reagents; D004247:DNA
keywords: DNA rearrangement; coumarins; interstrand crosslink; photoligation; photorelease