The X family portrait: structural insights into biological functions of X family polymerases

DNA Repair (Amst). 2007 Dec 1;6(12):1709-25. doi: 10.1016/j.dnarep.2007.05.009. Epub 2007 Jul 12.


The mammalian family X DNA polymerases (DNA polymerases beta, lambda, mu, and TdT) contribute to base excision repair and double-strand break repair by virtue of their ability to fill short gaps in DNA. Structural information now exists for all four of these enzymes, making this the first mammalian polymerase family whose structural portrait is complete. Here we consider how distinctive structural features of these enzymes contribute to their biological functions in vivo.

Publication types

  • Research Support, N.I.H., Intramural
  • Review

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Catalysis
  • DNA Repair
  • DNA-Directed DNA Polymerase / chemistry*
  • DNA-Directed DNA Polymerase / metabolism
  • DNA-Directed DNA Polymerase / physiology*
  • Humans
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Conformation
  • Sequence Homology, Amino Acid


  • DNA-Directed DNA Polymerase