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Updated: Aug 11, 2026

Characterization of Molecular Mechanisms of In vivo UVR Induced Cataract
Published on: November 28, 2012
Action of a nuclease from rat nuclei on UV-irradiated DNA
Abstract:
An Mg(2+)-dependent nuclease was highly purified from rat-liver nuclei. The nuclease activity was enhanced in ultraviolet light (UV)-irradiated dsDNA, but not in unirradiated dsDNA. Irrespective of UV irradiation, ssDNA was readily cleaved by this enzyme. UV-irradiated plasmid DNA was incubated with this enzyme and subjected to the template primer activity assay with a Klenow polymerase. With increasing incubation time, the activity was enhanced in the circular-relaxed and linear forms, but not in the superhelical form. These results implied that this enzyme excises UV-damaged sites in dsDNA to form single strand gaps for repair synthesis.
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