Growth retardation and leaky SCID phenotype of Ku70-deficient mice

Immunity. 1997 Nov;7(5):653-65. doi: 10.1016/s1074-7613(00)80386-6.


Ku70, Ku80, and DNA-PKcs are subunits of the DNA-dependent protein kinase (DNA-PK), an enzyme implicated in DNA double-stranded break repair and V(D)J recombination. Our Ku70-deficient mice were about 50% the size of control littermates, and their fibroblasts were ionizing radiation sensitive and displayed premature senescence associated with the accumulation of nondividing cells. Ku70-deficient mice lacked mature B cells or serum immunoglobulin but, unexpectedly, reproducibly developed small populations of thymic and peripheral alpha/beta T lineage cells and had a significant incidence of thymic lymphomas. In association with B and T cell developmental defects, Ku70-deficient cells were severely impaired for joining of V(D)J coding and recombination signal sequences. These unanticipated features of the Ku70-deficient phenotype with respect to lymphocyte development and V(D)J recombination may reflect differential functions of the three DNA-PK components.

Publication types

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

MeSH terms

  • Animals
  • Antigens, Nuclear*
  • B-Lymphocytes / cytology
  • Cell Cycle
  • Cells, Cultured
  • Cellular Senescence
  • DNA Damage
  • DNA Helicases*
  • DNA Repair
  • DNA-Activated Protein Kinase
  • DNA-Binding Proteins / physiology*
  • Fetal Growth Retardation / genetics
  • Fibroblasts / cytology
  • Gene Rearrangement, B-Lymphocyte*
  • Gene Rearrangement, T-Lymphocyte*
  • Ku Autoantigen
  • Mice
  • Mice, Knockout
  • Mice, SCID / genetics*
  • Nuclear Proteins / physiology*
  • Protein-Serine-Threonine Kinases / deficiency*
  • T-Lymphocytes / cytology
  • Thymus Neoplasms / genetics


  • Antigens, Nuclear
  • DNA-Binding Proteins
  • Nuclear Proteins
  • DNA-Activated Protein Kinase
  • Protein-Serine-Threonine Kinases
  • DNA Helicases
  • XRCC5 protein, human
  • Xrcc6 protein, human
  • Xrcc6 protein, mouse
  • Ku Autoantigen