Dimerization, translocation and localization of Ku70 and Ku80 proteins

J Radiat Res. 2002 Sep;43(3):223-36. doi: 10.1269/jrr.43.223.


The Ku protein is a complex of two subunits, Ku70 and Ku80, and was originally identified as an autoantigen recognized by the sera of patients with autoimmune diseases. The Ku protein plays a key role in multiple nuclear processes, e.g., DNA repair, chromosome maintenance, transcription regulation, and V(D)J recombination. The mechanism underlying the regulation of all the diverse functions of Ku is still unclear, although it seems that Ku is a multifunctional protein that works in nuclei. On the other hand, several studies have reported cytoplasmic or cell surface localization of Ku in various cell types. To clarify the fundamental characteristics of Ku, we have examined the expression, heterodimerization, subcellular localization, chromosome location, and molecular mechanisms of the nuclear transport of Ku70 and Ku80. The mechanism that regulates for nuclear localization of Ku70 and Ku80 appears to play, at least in part, a key role in regulating the physiological function of Ku in vivo.

Publication types

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

MeSH terms

  • Amino Acid Sequence / genetics
  • Animals
  • Antigens, Nuclear*
  • Biological Transport
  • Cell Nucleus / metabolism*
  • Chromosome Mapping
  • DNA Helicases*
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Dimerization
  • Humans
  • Ku Autoantigen
  • Molecular Sequence Data
  • Nuclear Proteins / chemistry*
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Protein Isoforms / chemistry
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism


  • Antigens, Nuclear
  • DNA-Binding Proteins
  • Nuclear Proteins
  • Protein Isoforms
  • DNA Helicases
  • XRCC5 protein, human
  • Xrcc6 protein, human
  • Ku Autoantigen