repair synthesis

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repair synthesis The enzymatic excision and replacement of regions of damaged DNA. The defective single-stranded segments of DNA are cut out, correct bases are inserted using the complementary strand as a template, and these are interlocked by a DNA polymerase. A polynucleotide ligase joins the 2 ends of the broken strand to complete the repair. An example is the removal by a nuclease enzyme of a thymine dimer that has been induced by UV radiation of the DNA molecule.

repair synthesis

views updated

repair synthesis The enzymatic excision and replacement of regions of damaged DNA. The defective single-stranded segments of DNA are cut out, correct bases are inserted using the complementary strand as a template, and these are interlocked by a DNA polymerase. A polynucleotide ligase joins the two ends of the broken strand to complete the repair. An example is the removal by a nuclease enzyme of a thymine dimer that has been induced by ultraviolet radiation of the DNA molecule.