Excision of deoxyribose phosphate residues by DNA polymerase beta during DNA repair.
Eukaryotic DNA polymerase beta (pol beta) can catalyze DNA synthesis during base excision DNA repair. It is shown here that pol beta also catalyzes release of 5'-terminal deoxyribose phosphate (dRP) residues from incised apurinic-apyrimidinic sites, which are common intermediate products in base excision repair. The catalytic domain for this activity resides within an amino-terminal 8-kilodalton fragment of pol beta, which comprises a distinct structural domain of the enzyme. Magnesium is required for the release of dRP from double-stranded DNA but not from a single-stranded oligonucleotide. Analysis of the released products indicates that the excision reaction occurs by beta-elimination rather than hydrolysis.
Matsumoto
Y
Y
Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
Kim
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K
D000818:Animals; D001080:Apurinic Acid; D001483:Base Sequence; D001665:Binding Sites; D004247:DNA / Q000378:metabolism*; D011088:DNA Ligases / Q000378:metabolism; D004256:DNA Polymerase I / Q000378:metabolism*; D004260:DNA Repair; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase; D043223:Deoxyribonuclease IV (Phage T4-Induced); D004492:Edetic Acid / Q000494:pharmacology; D006868:Hydrolysis; D008190:Lyases / Q000378:metabolism; D008969:Molecular Sequence Data; D011119:Polynucleotides; D017434:Protein Structure, Tertiary; D051381:Rats; D012267:Ribosemonophosphates / Q000378:metabolism*; D014982:Xenopus laevis
D011119:Polynucleotides; D012267:Ribosemonophosphates; C001790:apyrimidinic acid; D001080:Apurinic Acid; D004247:DNA; D004492:Edetic Acid; D004256:DNA Polymerase I; D043223:Deoxyribonuclease IV (Phage T4-Induced); D008190:Lyases; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase; D011088:DNA Ligases