Base excision repair

Cold Spring Harb Perspect Biol. 2013 Apr 1;5(4):a012583. doi: 10.1101/cshperspect.a012583.

Abstract

Base excision repair (BER) corrects DNA damage from oxidation, deamination and alkylation. Such base lesions cause little distortion to the DNA helix structure. BER is initiated by a DNA glycosylase that recognizes and removes the damaged base, leaving an abasic site that is further processed by short-patch repair or long-patch repair that largely uses different proteins to complete BER. At least 11 distinct mammalian DNA glycosylases are known, each recognizing a few related lesions, frequently with some overlap in specificities. Impressively, the damaged bases are rapidly identified in a vast excess of normal bases, without a supply of energy. BER protects against cancer, aging, and neurodegeneration and takes place both in nuclei and mitochondria. More recently, an important role of uracil-DNA glycosylase UNG2 in adaptive immunity was revealed. Furthermore, other DNA glycosylases may have important roles in epigenetics, thus expanding the repertoire of BER proteins.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Cell Nucleus / metabolism
  • DNA / genetics*
  • DNA Damage
  • DNA Glycosylases / genetics
  • DNA Polymerase beta / metabolism
  • DNA Repair*
  • Epigenesis, Genetic
  • Escherichia coli / enzymology
  • Humans
  • Mice
  • Mice, Knockout
  • Mitochondria / metabolism
  • Models, Molecular
  • Mutagenesis
  • Neoplasms / enzymology
  • Oxygen / chemistry
  • Poly(ADP-ribose) Polymerases / metabolism
  • Protein Conformation

Substances

  • DNA
  • Poly(ADP-ribose) Polymerases
  • DNA Polymerase beta
  • CCNO protein, human
  • DNA Glycosylases
  • Oxygen