Gene Symbol: Ku80
Description: X-ray repair cross complementing 5
Alias: KARP-1, KARP1, KU80, KUB2, Ku86, NFIV, X-ray repair cross-complementing protein 5, 86 kDa subunit of Ku antigen, ATP-dependent DNA helicase 2 subunit 2, ATP-dependent DNA helicase II 80 kDa subunit, CTC box-binding factor 85 kDa subunit, CTC85, CTCBF, DNA repair protein XRCC5, Ku autoantigen, 80kDa, Ku86 autoantigen related protein 1, TLAA, X-ray repair complementing defective repair in Chinese hamster cells 5 (double-strand-break rejoining), lupus Ku autoantigen protein p86, nuclear factor IV, thyroid-lupus autoantigen
Species: human
Products:     Ku80

Top Publications

  1. Singleton B, Torres Arzayus M, Rottinghaus S, Taccioli G, Jeggo P. The C terminus of Ku80 activates the DNA-dependent protein kinase catalytic subunit. Mol Cell Biol. 1999;19:3267-77 pubmed
    ..We have carried out a 3' deletion analysis of Ku80, the larger subunit of Ku, and shown that the C-terminal 178 amino acid residues are dispensable for DNA end-..
  2. Li L, Olvera J, Yoder K, Mitchell R, Butler S, Lieber M, et al. Role of the non-homologous DNA end joining pathway in the early steps of retroviral infection. EMBO J. 2001;20:3272-81 pubmed
    ..Consistent with this, the NHEJ proteins Ku70 and Ku80 were found to be bound to purified retroviral replication intermediates...
  3. Rivera Calzada A, Spagnolo L, Pearl L, Llorca O. Structural model of full-length human Ku70-Ku80 heterodimer and its recognition of DNA and DNA-PKcs. EMBO Rep. 2007;8:56-62 pubmed
    Recognition of DNA double-strand breaks during non-homologous end joining is carried out by the Ku70-Ku80 protein, a 150 kDa heterodimer that recruits the DNA repair kinase DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to the ..
  4. Ting N, Yu Y, Pohorelic B, Lees Miller S, Beattie T. Human Ku70/80 interacts directly with hTR, the RNA component of human telomerase. Nucleic Acids Res. 2005;33:2090-8 pubmed
  5. Fu Y, Yu J, Cheng T, Lou M, Hsu G, Wu C, et al. Breast cancer risk associated with genotypic polymorphism of the nonhomologous end-joining genes: a multigenic study on cancer susceptibility. Cancer Res. 2003;63:2440-6 pubmed
    ..variation in the genome, to examine these hypotheses, we have genotyped 30 SNPs in all five NHEJ genes (Ku70, Ku80, DNA-PKcs, Ligase IV, and XRCC4) in 254 primary breast cancer patients and 379 healthy controls...
  6. Cohen H, Lavu S, Bitterman K, Hekking B, Imahiyerobo T, Miller C, et al. Acetylation of the C terminus of Ku70 by CBP and PCAF controls Bax-mediated apoptosis. Mol Cell. 2004;13:627-38 pubmed
    ..We demonstrate that increased acetylation of Ku70 disrupts the Ku70-Bax interaction and coincides with cytoplasmic accumulation of CBP. These results shed light on the role of acetyltransferases as tumor suppressors. ..
  7. Falck J, Coates J, Jackson S. Conserved modes of recruitment of ATM, ATR and DNA-PKcs to sites of DNA damage. Nature. 2005;434:605-11 pubmed
    ..Here we identify related, conserved carboxy-terminal motifs in human Nbs1, ATRIP and Ku80 proteins that are required for their interaction with ATM, ATR and DNA-PKcs, respectively...
  8. Wang H, Liu C, Chiu C, Chiang S, Wang C, Wang R, et al. Significant association of DNA repair gene Ku80 genotypes with breast cancer susceptibility in Taiwan. Anticancer Res. 2009;29:5251-4 pubmed
    To evaluate the association between the genotypes of the heterodimeric DNA-binding component, Ku80 gene and the breast cancer risk in Taiwan...
  9. Yin H, Glass J. In prostate cancer cells the interaction of C/EBPalpha with Ku70, Ku80, and poly(ADP-ribose) polymerase-1 increases sensitivity to DNA damage. J Biol Chem. 2006;281:11496-505 pubmed
    ..Ku70, Ku80, and poly(ADP-ribose) polymerase-1 (PARP-1) were identified as proteins that associated with C/EBPalpha...

More Information


  1. Spagnolo L, Rivera Calzada A, Pearl L, Llorca O. Three-dimensional structure of the human DNA-PKcs/Ku70/Ku80 complex assembled on DNA and its implications for DNA DSB repair. Mol Cell. 2006;22:511-9 pubmed
    ..DNA-PKcs is recruited to DSBs by the Ku70/Ku80 heterodimer, with which it forms the core of a multiprotein complex that promotes synapsis of the broken DNA ends...
  2. Grote J, König S, Ackermann D, Sopalla C, Benedyk M, Los M, et al. Identification of poly(ADP-ribose)polymerase-1 and Ku70/Ku80 as transcriptional regulators of S100A9 gene expression. BMC Mol Biol. 2006;7:48 pubmed
    ..Using the MRE motif for a pull-down assay, poly(ADP-ribose)polymerase-1 (PARP-1) and the heterodimeric complex Ku70/Ku80 were identified by mass spectrometry and confirmed by chromatin immunoprecipitation...
  3. Shi L, Qiu D, Zhao G, Corthesy B, Lees Miller S, Reeves W, et al. Dynamic binding of Ku80, Ku70 and NF90 to the IL-2 promoter in vivo in activated T-cells. Nucleic Acids Res. 2007;35:2302-10 pubmed
    ..ARRE DNA-binding subunits were identified as NF90, NF45 and systemic lupus erythematosis autoantigens, Ku80 and Ku70...
  4. Masson C, Bury Moné S, Guiot E, Saez Cirion A, Schoevaert Brossault D, Brachet Ducos C, et al. Ku80 participates in the targeting of retroviral transgenes to the chromatin of CHO cells. J Virol. 2007;81:7924-32 pubmed
    ..We describe here the effect of Ku80 on both provirus integration and the resulting transgene expression in cells transduced with retroviral vectors...
  5. Ruis B, Fattah K, Hendrickson E. The catalytic subunit of DNA-dependent protein kinase regulates proliferation, telomere length, and genomic stability in human somatic cells. Mol Cell Biol. 2008;28:6182-95 pubmed publisher
    ..kinase comprised of a 469-kDa catalytic subunit (DNA-PK(cs)) and the DNA binding regulatory heterodimeric (Ku70/Ku86) complex Ku...
  6. Kim E, Li K, Lieu C, Tong S, Kawai S, Fukutomi T, et al. Expression of apolipoprotein C-IV is regulated by Ku antigen/peroxisome proliferator-activated receptor gamma complex and correlates with liver steatosis. J Hepatol. 2008;49:787-98 pubmed publisher
    ..defined a 163-bp ApoC-IV promoter as a core protein responsive element, and identified Ku antigen complex (Ku70 and Ku80) as well as nuclear receptors PPARgamma/RXRalpha as key regulators of ApoC-IV gene expression...
  7. Ghosh G, Li G, Myung K, Hendrickson E. The lethality of Ku86 (XRCC5) loss-of-function mutations in human cells is independent of p53 (TP53). Radiat Res. 2007;167:66-79 pubmed
    b>Ku86 is one of the two regulatory subunits of the DNA-PK (DNA-dependent protein kinase) complex that is required for DNA double-strand break repair in mammalian cells...
  8. Idogawa M, Masutani M, Shitashige M, Honda K, Tokino T, Shinomura Y, et al. Ku70 and poly(ADP-ribose) polymerase-1 competitively regulate beta-catenin and T-cell factor-4-mediated gene transactivation: possible linkage of DNA damage recognition and Wnt signaling. Cancer Res. 2007;67:911-8 pubmed
    ..Using immunoprecipitation and mass spectrometry, we found that two Ku proteins, Ku70 and Ku80, were also associated with the complex...
  9. Heo K, Kim H, Choi S, Choi J, Kim K, Gu J, et al. FACT-mediated exchange of histone variant H2AX regulated by phosphorylation of H2AX and ADP-ribosylation of Spt16. Mol Cell. 2008;30:86-97 pubmed publisher
    ..Thus, these data establish FACT as the major regulator involved in H2AX exchange process that is modulated by H2AX phosphorylation and Spt16 ADP-ribosylation. ..
  10. Olsen B, Issinger O, Guerra B. Regulation of DNA-dependent protein kinase by protein kinase CK2 in human glioblastoma cells. Oncogene. 2010;29:6016-26 pubmed publisher
    ..These results indicate that CK2 has an important role in the modulation of DNA-PKcs activity and its phosphorylation status providing important insights into the mechanisms by which DNA-PKcs is regulated in vivo. ..
  11. Taylor T, Knipe D. Proteomics of herpes simplex virus replication compartments: association of cellular DNA replication, repair, recombination, and chromatin remodeling proteins with ICP8. J Virol. 2004;78:5856-66 pubmed
    ..nonhomologous and homologous recombination, including the catalytic subunit of the DNA-dependent protein kinase, Ku86, and Rad50; and (iii) chromatin remodeling, including BRG1, BRM, hSNF2H, BAF155, mSin3a, and histone deacetylase 2...
  12. Ahel D, Horejsí Z, Wiechens N, Polo S, Garcia Wilson E, Ahel I, et al. Poly(ADP-ribose)-dependent regulation of DNA repair by the chromatin remodeling enzyme ALC1. Science. 2009;325:1240-3 pubmed publisher
    ..Furthermore, we show that depletion or overexpression of ALC1 results in sensitivity to DNA-damaging agents. Collectively, these results provide new insights into the mechanisms by which poly(ADP-ribose) regulates DNA repair. ..
  13. Taccioli G, Gottlieb T, Blunt T, Priestley A, Demengeot J, Mizuta R, et al. Ku80: product of the XRCC5 gene and its role in DNA repair and V(D)J recombination. Science. 1994;265:1442-5 pubmed
    ..Thus, the Ku protein is involved in DNA repair and in V(D)J recombination, and these results may also indicate a role for the Ku-DNA-dependent protein kinase complex in those same processes. ..
  14. Song J, Lim J, Kim H, Morio T, Kim K. Oxidative stress induces nuclear loss of DNA repair proteins Ku70 and Ku80 and apoptosis in pancreatic acinar AR42J cells. J Biol Chem. 2003;278:36676-87 pubmed
    ..It has been hypothesized that oxidative stress may induce a decrease in the Ku70 and Ku80 levels and apoptosis in pancreatic acinar cells...
  15. Baekelandt V, Claeys A, Cherepanov P, De Clercq E, De Strooper B, Nuttin B, et al. DNA-Dependent protein kinase is not required for efficient lentivirus integration. J Virol. 2000;74:11278-85 pubmed
    ..However, no inhibition of lentivirus vector-mediated transduction or HIV-1 replication by 3-methoxybenzamide, a known PARP inhibitor, was observed. In conclusion, DNA-PK and PARP are not essential for lentivirus integration. ..
  16. Walker J, Corpina R, Goldberg J. Structure of the Ku heterodimer bound to DNA and its implications for double-strand break repair. Nature. 2001;412:607-14 pubmed
    The Ku heterodimer (Ku70 and Ku80 subunits) contributes to genomic integrity through its ability to bind DNA double-strand breaks and facilitate repair by the non-homologous end-joining pathway...
  17. Li B, Comai L. Functional interaction between Ku and the werner syndrome protein in DNA end processing. J Biol Chem. 2000;275:28349-52 pubmed
    ..Peptide sequence analysis indicates that the two proteins are identical to Ku70 and Ku80, a heterodimer involved in double strand DNA break repair by non-homologous DNA end joining...
  18. Nick McElhinny S, Snowden C, McCarville J, Ramsden D. Ku recruits the XRCC4-ligase IV complex to DNA ends. Mol Cell Biol. 2000;20:2996-3003 pubmed
    ..We have therefore defined cell-free conditions that reflect the genetic requirement for ligase IV in cellular end joining and consequently can explain in molecular terms why this factor is required. ..
  19. Sartorius C, Takimoto G, Richer J, Tung L, Horwitz K. Association of the Ku autoantigen/DNA-dependent protein kinase holoenzyme and poly(ADP-ribose) polymerase with the DNA binding domain of progesterone receptors. J Mol Endocrinol. 2000;24:165-82 pubmed
    ..DNA-dependent protein kinase (DNA-PK) holoenzyme: its DNA binding regulatory heterodimers consisting of Ku70 and Ku86, and the 460 kDa catalytic subunit, DNA-PK(CS)...
  20. Hsu H, Gilley D, Blackburn E, Chen D. Ku is associated with the telomere in mammals. Proc Natl Acad Sci U S A. 1999;96:12454-8 pubmed
    ..The highly expressed Ku heterodimer, composed of 70 and 80 K(d) subunits (Ku70 and Ku80), is the high-affinity DNA binding component of the DNA-dependent protein kinase...
  21. Wei S, Xiong M, Zhan D, Liang B, Wang Y, Gutmann D, et al. Ku80 functions as a tumor suppressor in hepatocellular carcinoma by inducing S-phase arrest through a p53-dependent pathway. Carcinogenesis. 2012;33:538-47 pubmed publisher
    b>Ku80 is a component of the protein complex called DNA-dependent protein kinase, which is involved in DNA double-strand break repair and multiple other functions...
  22. Ting N, Kao P, Chan D, Lintott L, Lees Miller S. DNA-dependent protein kinase interacts with antigen receptor response element binding proteins NF90 and NF45. J Biol Chem. 1998;273:2136-45 pubmed
    ..Together, our data suggest that NF90, in complex with NF45, interacts with DNA-PKcs and Ku on DNA and that NF90 and NF45 may be important for the function of DNA-PK. ..
  23. Mo X, Dynan W. Subnuclear localization of Ku protein: functional association with RNA polymerase II elongation sites. Mol Cell Biol. 2002;22:8088-99 pubmed
    ..that the association of Ku with elongation proteins is mediated, in part, by a discrete C-terminal domain in the Ku80 subunit...
  24. Kang H, Lee Y, Shin J, Andrabi S, Chi Z, Gagné J, et al. Iduna is a poly(ADP-ribose) (PAR)-dependent E3 ubiquitin ligase that regulates DNA damage. Proc Natl Acad Sci U S A. 2011;108:14103-8 pubmed publisher
    ..that are either PARsylated or bind PAR including PAR polymerase-1, 2 (PARP1, 2), nucleolin, DNA ligase III, KU70, KU86, XRCC1, and histones...
  25. Kanno S, Kuzuoka H, Sasao S, Hong Z, Lan L, Nakajima S, et al. A novel human AP endonuclease with conserved zinc-finger-like motifs involved in DNA strand break responses. EMBO J. 2007;26:2094-103 pubmed
    ..PALF also interacts directly with KU86, LIGASEIV and phosphorylated XRCC4 proteins and possesses endo/exonuclease activity at protruding DNA ends...
  26. Bianchi A, de Lange T. Ku binds telomeric DNA in vitro. J Biol Chem. 1999;274:21223-7 pubmed
    ..Our results indicate that the DNA binding characteristics of Ku are consistent with its direct interaction with telomeric DNA in mammalian cells and its proposed role as a telomere end factor. ..
  27. Ye J, Ren Z, Gu Q, Wang L, Wang J. Ku80 is differentially expressed in human lung carcinomas and upregulated in response to irradiation in mice. DNA Cell Biol. 2011;30:987-94 pubmed publisher
    Based on the role of Ku80 in mediating radiation-induced DNA repair, we investigated Ku80 expression in human lung cancers of different pathological types and evaluated the effect of radiotherapy on Ku80 expression levels in a mouse model...
  28. Mari P, Florea B, Persengiev S, Verkaik N, Bruggenwirth H, Modesti M, et al. Dynamic assembly of end-joining complexes requires interaction between Ku70/80 and XRCC4. Proc Natl Acad Sci U S A. 2006;103:18597-602 pubmed
    ..Our results suggest that this assembly constitutes the core of the NHEJ reaction and that XRCC4 may serve as a flexible tether between Ku70/80 and ligase IV. ..
  29. Bennett S, Neher T, Shatilla A, Turchi J. Molecular analysis of Ku redox regulation. BMC Mol Biol. 2009;10:86 pubmed publisher
    ..The C-terminal domain and cysteine 493 of Ku80 were investigated for their contribution to redox regulation of Ku...
  30. Zhang S, Schlott B, Görlach M, Grosse F. DNA-dependent protein kinase (DNA-PK) phosphorylates nuclear DNA helicase II/RNA helicase A and hnRNP proteins in an RNA-dependent manner. Nucleic Acids Res. 2004;32:1-10 pubmed
    ..This RNA binding affinity of DNA-PK can be ascribed to its Ku86 subunit. Consistently, poly(rG) most strongly stimulated the DNA-PK-catalyzed phosphorylation of NDH II...
  31. Andrews B, Lehman J, Turchi J. Kinetic analysis of the Ku-DNA binding activity reveals a redox-dependent alteration in protein structure that stimulates dissociation of the Ku-DNA complex. J Biol Chem. 2006;281:13596-603 pubmed
    ..The results support a model for the interaction of Ku with DNA that is regulated by redox status and is achieved by altering the dissociation of the Ku-DNA complex. ..
  32. Kelavkar U, Wang S, Badr K. Ku autoantigen (DNA helicase) is required for interleukins-13/-4-induction of 15-lipoxygenase-1 gene expression in human epithelial cells. Genes Immun. 2000;1:237-50 pubmed
    ..mass spectrometry (MALDI-MS) of the tryptic digests of these proteins, identified one as the 86 kDA Lupus KU autoantigen protein P86 and the second as the 70 kDa Lupus KU autoantigen protein P70...
  33. Fattah F, Lee E, Weisensel N, Wang Y, Lichter N, Hendrickson E. Ku regulates the non-homologous end joining pathway choice of DNA double-strand break repair in human somatic cells. PLoS Genet. 2010;6:e1000855 pubmed publisher
    ..Unexpectedly, Ku86-null cells showed wild-type levels of DNA DSB repair activity that was dominated by microhomology joining events ..
  34. Reichman T, Muniz L, Mathews M. The RNA binding protein nuclear factor 90 functions as both a positive and negative regulator of gene expression in mammalian cells. Mol Cell Biol. 2002;22:343-56 pubmed
    ..This report characterizes NF90 as both a positive and negative regulator of gene expression, depending on the promoter context, and suggests a role for NF45 as a regulator of NF90. ..
  35. Zheng Y, Ao Z, Wang B, Jayappa K, Yao X. Host protein Ku70 binds and protects HIV-1 integrase from proteasomal degradation and is required for HIV replication. J Biol Chem. 2011;286:17722-35 pubmed publisher
    ..Overall, this report provides another example of how HIV-1 hijacks host cellular machinery to protect the virus itself and to facilitate its replication. ..
  36. Karmakar P, Snowden C, Ramsden D, Bohr V. Ku heterodimer binds to both ends of the Werner protein and functional interaction occurs at the Werner N-terminus. Nucleic Acids Res. 2002;30:3583-91 pubmed
    ..The Ku70 subunit specifically interacts with the N-terminus (amino acids 1-368) of WRN, while the Ku80 subunit interacts with its C-terminus (amino acids 940- 1432)...
  37. Mischo H, Hemmerich P, Grosse F, Zhang S. Actinomycin D induces histone gamma-H2AX foci and complex formation of gamma-H2AX with Ku70 and nuclear DNA helicase II. J Biol Chem. 2005;280:9586-94 pubmed
    ..Taken together, these results suggest that histone gamma-H2AX promotes binding of NDH II to transcriptionally stalled sites on chromosomal DNA. ..
  38. Lou Z, Chen B, Asaithamby A, Minter Dykhouse K, Chen D, Chen J. MDC1 regulates DNA-PK autophosphorylation in response to DNA damage. J Biol Chem. 2004;279:46359-62 pubmed
    ..Therefore, MDC1 acts not only as a mediator of DNA damage checkpoint but also as a mediator of DNA damage repair. ..
  39. Sucharov C, Helmke S, Langer S, Perryman M, Bristow M, Leinwand L. The Ku protein complex interacts with YY1, is up-regulated in human heart failure, and represses alpha myosin heavy-chain gene expression. Mol Cell Biol. 2004;24:8705-15 pubmed
    ..Through peptide mass spectrometry, we identified this binding activity to be a heterodimer of Ku70 and Ku80. Expression of Ku represses the human alphaMyHC promoter in neonatal rat ventricular myocytes...
  40. Chai W, Ford L, Lenertz L, Wright W, Shay J. Human Ku70/80 associates physically with telomerase through interaction with hTERT. J Biol Chem. 2002;277:47242-7 pubmed
    ..The DNA repair protein Ku (a heterodimer of Ku70 and Ku80 subunits) associates with mammalian telomeres and contributes to telomere maintenance...
  41. Yano K, Morotomi Yano K, Lee K, Chen D. Functional significance of the interaction with Ku in DNA double-strand break recognition of XLF. FEBS Lett. 2011;585:841-6 pubmed publisher
    ..These results demonstrate the significance of Ku-XLF interaction in the molecular assembly of NHEJ factors. ..
  42. Wang H, Fang R, Cho J, Libermann T, Oettgen P. Positive and negative modulation of the transcriptional activity of the ETS factor ESE-1 through interaction with p300, CREB-binding protein, and Ku 70/86. J Biol Chem. 2004;279:25241-50 pubmed
    ..We have determined that Ku70, Ku86, p300, and CREB-binding protein (CBP) are ESE-1 interacting proteins...
  43. Li B, Navarro S, Kasahara N, Comai L. Identification and biochemical characterization of a Werner's syndrome protein complex with Ku70/80 and poly(ADP-ribose) polymerase-1. J Biol Chem. 2004;279:13659-67 pubmed
    ..Two of these proteins, Ku70 and Ku80, were identified by immunoblot analysis...
  44. Nolens G, Pignon J, Koopmansch B, ElMoualij B, Zorzi W, De Pauw E, et al. Ku proteins interact with activator protein-2 transcription factors and contribute to ERBB2 overexpression in breast cancer cell lines. Breast Cancer Res. 2009;11:R83 pubmed publisher
    ..Among the proteins retained specifically on GST-AP2 coated beads Ku70 and Ku80 proteins were identified by mass spectrometry...
  45. Li R, Yang Y, An Y, Zhou Y, Liu Y, Yu Q, et al. Genetic polymorphisms in DNA double-strand break repair genes XRCC5, XRCC6 and susceptibility to hepatocellular carcinoma. Carcinogenesis. 2011;32:530-6 pubmed publisher
    ..In conclusion, XRCC5 variants may play a role in determining individual's HCC susceptibility, which warranted validation in larger studies. ..
  46. Warriar N, Page N, Govindan M. Expression of human glucocorticoid receptor gene and interaction of nuclear proteins with the transcriptional control element. J Biol Chem. 1996;271:18662-71 pubmed
    ..Both Ku80 and Ku70 polypeptides were present in high concentrations in human placenta and HeLa cells...
  47. Wang Y, Ghosh G, Hendrickson E. Ku86 represses lethal telomere deletion events in human somatic cells. Proc Natl Acad Sci U S A. 2009;106:12430-5 pubmed publisher
    ..One essential NHEJ factor is Ku, which consists of a heterodimer of Ku70 and Ku86. In a plethora of model systems, null mutations for Ku70 or Ku86 present with defects in DNA DSB repair, variable(..
  48. Ju B, Lunyak V, Perissi V, Garcia Bassets I, Rose D, Glass C, et al. A topoisomerase IIbeta-mediated dsDNA break required for regulated transcription. Science. 2006;312:1798-802 pubmed
    ..Our data mechanistically link DNA topoisomerase IIbeta-dependent dsDNA breaks and the components of the DNA damage and repair machinery in regulated gene transcription. ..
  49. Lebrun P, Montminy M, Van Obberghen E. Regulation of the pancreatic duodenal homeobox-1 protein by DNA-dependent protein kinase. J Biol Chem. 2005;280:38203-10 pubmed
    ..We identified new proteins associated with PDX-1 by mass spectrometry. These proteins, Ku70 and Ku80, are regulatory subunits of DNA-dependent protein kinase (DNA-PK)...
  50. Sibani S, Price G, Zannis Hadjopoulos M. Ku80 binds to human replication origins prior to the assembly of the ORC complex. Biochemistry. 2005;44:7885-96 pubmed
    ..In this study, using HCT116 Ku80+/- haplo-insufficient and Orc2(delta/-) hypomorphic cells, the order of binding of Ku and the human origin ..
  51. Drouet J, Delteil C, Lefrançois J, Concannon P, Salles B, Calsou P. DNA-dependent protein kinase and XRCC4-DNA ligase IV mobilization in the cell in response to DNA double strand breaks. J Biol Chem. 2005;280:7060-9 pubmed
    ..DNA-PK comprises the Ku70/Ku80 heterodimer and the catalytic subunit DNA-PKcs...
  52. O Connor M, Safari A, Liu D, Qin J, Songyang Z. The human Rap1 protein complex and modulation of telomere length. J Biol Chem. 2004;279:28585-91 pubmed
    ..In addition to TRF2, we found DNA repair proteins Rad50, Mre11, PARP1 (poly(ADP-ribose) polymerase), and Ku86/Ku70 to be in this telomeric complex...
  53. DeFazio L, Stansel R, Griffith J, Chu G. Synapsis of DNA ends by DNA-dependent protein kinase. EMBO J. 2002;21:3192-200 pubmed
    ..Our results suggest that DNA-PK(CS) brings DNA ends together and then undergoes activation of its kinase, presumably to regulate subsequent steps for processing and ligation of the ends. ..
  54. Song K, Jung D, Jung Y, Lee S, Lee I. Interaction of human Ku70 with TRF2. FEBS Lett. 2000;481:81-5 pubmed
    ..We have utilized the yeast two-hybrid system to identify Ku70-interacting proteins other than Ku80. Two reactive clones were found to encode the dimerization domain of TRF2, a mammalian telomeric protein that binds ..
  55. Gell D, Jackson S. Mapping of protein-protein interactions within the DNA-dependent protein kinase complex. Nucleic Acids Res. 1999;27:3494-502 pubmed
    ..two tightly-associated subunits of approximately 69 and approximately 83 kDa, which are termed Ku70 and Ku80 (or Ku86), respectively...
  56. Galande S, Kohwi Shigematsu T. Poly(ADP-ribose) polymerase and Ku autoantigen form a complex and synergistically bind to matrix attachment sequences. J Biol Chem. 1999;274:20521-8 pubmed
    ..These results provide a mechanistic link toward understanding the functional overlap of PARP and DNA-PK and suggest a novel role for these proteins in the regulation of chromatin structure and function. ..
  57. Mayeur G, Kung W, Martinez A, Izumiya C, Chen D, Kung H. Ku is a novel transcriptional recycling coactivator of the androgen receptor in prostate cancer cells. J Biol Chem. 2005;280:10827-33 pubmed
    ..AR directly interacts with both Ku70 and Ku80 in vivo and in vitro, as shown by co-immunoprecipitation, glutathione S-transferase pull-down, and Sf9 cell/..