Gene Symbol: Irbp
Description: Inverted repeat-binding protein
Alias: CG5247, DmKu70, Dmel\CG5247, IRBP, IRBP/Ku70, Ku70, YPF1, YPF1beta, Ypf1b, dp70, irbp, ku70, p70, inverted repeat-binding protein, CG5247-PA, CG5247-PB, Irbp-PA, Irbp-PB, yolk protein factor 1b
Species: fruit fly

Top Publications

  1. Beall E, Rio D. Drosophila IRBP/Ku p70 corresponds to the mutagen-sensitive mus309 gene and is involved in P-element excision in vivo. Genes Dev. 1996;10:921-33 pubmed
    ..We report here that a Drosophila mutagen-sensitive mutant, mus3O9, contains a mutation in IRBP (inverted repeat binding protein), the Drosophila homolog of the mammalian Ku p70 gene...
  2. Sekelsky J, Brodsky M, Burtis K. DNA repair in Drosophila: insights from the Drosophila genome sequence. J Cell Biol. 2000;150:F31-6 pubmed
  3. Yu A, McVey M. Synthesis-dependent microhomology-mediated end joining accounts for multiple types of repair junctions. Nucleic Acids Res. 2010;38:5706-17 pubmed publisher
    ..This suggests that a single underlying mechanism could be responsible for all three repair product types. Genetic analysis indicates that SD-MMEJ is Ku70, Lig4 and Rad51-independent but impaired in mus308 (POLQ) mutants.
  4. Melnikova L, Biessmann H, Georgiev P. The Ku protein complex is involved in length regulation of Drosophila telomeres. Genetics. 2005;170:221-35 pubmed
    ..Here we show that a decrease in Ku70 or Ku80 gene dosage causes a sharp increase in the frequency of HeT-A and TART attachments to a broken chromosome ..
  5. Johnson Schlitz D, Flores C, Engels W. Multiple-pathway analysis of double-strand break repair mutations in Drosophila. PLoS Genet. 2007;3:e50 pubmed
  6. Sekelsky J, Burtis K, Hawley R. Damage control: the pleiotropy of DNA repair genes in Drosophila melanogaster. Genetics. 1998;148:1587-98 pubmed
  7. Gloor G, Moretti J, Mouyal J, Keeler K. Distinct P-element excision products in somatic and germline cells of Drosophila melanogaster. Genetics. 2000;155:1821-30 pubmed
    ..Enhanced expression of the Drosophila homologue of the Ku70 protein did not affect the structure of the somatic footprints...
  8. Kusano K, Johnson Schlitz D, Engels W. Sterility of Drosophila with mutations in the Bloom syndrome gene--complementation by Ku70. Science. 2001;291:2600-2 pubmed
    ..The mutant Dmblm phenotypes were partially rescued by an extra copy of the DNA repair gene Ku70, indicating that the two genes functionally interact in vivo.
  9. Zhang Y, Lin N, Carroll P, Chan G, Guan B, Xiao H, et al. Epigenetic blocking of an enhancer region controls irradiation-induced proapoptotic gene expression in Drosophila embryos. Dev Cell. 2008;14:481-93 pubmed publisher
    ..Thus, direct epigenetic regulation of two proapoptotic genes controls cellular sensitivity to cytotoxic stimuli. ..

More Information


  1. Zhang C, Hong Z, Ma W, Ma D, Qian Y, Xie W, et al. Drosophila UTX coordinates with p53 to regulate ku80 expression in response to DNA damage. PLoS ONE. 2013;8:e78652 pubmed publisher
    ..In contrast, the loss of utx has little impact on the expression of ku70, mre11, hid and reaper, suggesting the specific regulation of ku80 expression by UTX...
  2. Jacoby D, Wensink P. DNA binding specificities of YPF1, a Drosophila homolog to the DNA binding subunit of human DNA-dependent protein kinase, Ku. J Biol Chem. 1996;271:16827-32 pubmed
    b>YPF1, a heterodimeric protein from Drosophila melanogaster, is a homolog to Ku, the DNA binding subunit of human DNA-dependent protein kinase...
  3. Mitsis P, Wensink P. Identification of yolk protein factor 1, a sequence-specific DNA-binding protein from Drosophila melanogaster. J Biol Chem. 1989;264:5188-94 pubmed
    ..We have identified a sequence-specific DNA-binding protein, yolk protein factor 1 (YPF1), that has high affinity for a 31-bp sequence in the yolk protein 1 gene...
  4. Tamura T, Sone M, Iwatsubo T, Tagawa K, Wanker E, Okazawa H. Ku70 alleviates neurodegeneration in Drosophila models of Huntington's disease. PLoS ONE. 2011;6:e27408 pubmed publisher
    ..We previously reported that Ku70, a critical molecule for DNA double strand break (DSB) repair, is involved in the pathology of Huntington's disease ..
  5. Cenci G, Ciapponi L, Gatti M. The mechanism of telomere protection: a comparison between Drosophila and humans. Chromosoma. 2005;114:135-45 pubmed
    ..In addition, it has been shown that HP1 and both components of the Drosophila Ku70/80 heterodimer act as negative regulators of telomere length...
  6. Pastink A, Lohman P. Repair and consequences of double-strand breaks in DNA. Mutat Res. 1999;428:141-56 pubmed
  7. Smith G, Jackson S. The DNA-dependent protein kinase. Genes Dev. 1999;13:916-34 pubmed
  8. Jacoby D, Wensink P. Yolk protein factor 1 is a Drosophila homolog of Ku, the DNA-binding subunit of a DNA-dependent protein kinase from humans. J Biol Chem. 1994;269:11484-91 pubmed
    Yolk protein factor 1 (YPF1) is a heterodimeric DNA-binding protein from Drosophila melanogaster...
  9. Beaucher M, Zheng X, Amariei F, Rong Y. Multiple pathways suppress telomere addition to DNA breaks in the Drosophila germline. Genetics. 2012;191:407-17 pubmed publisher
    ..establishment. In the ku70 mutant background, telomere establishment was preceded by excessive degradation of DSB ends, which were stabilized ..
  10. Min B, Weinert B, Rio D. Interplay between Drosophila Bloom's syndrome helicase and Ku autoantigen during nonhomologous end joining repair of P element-induced DNA breaks. Proc Natl Acad Sci U S A. 2004;101:8906-11 pubmed
    ..have used RNA interference (RNAi) to knock down expression of DmBLM and one or both of the Drosophila Ku subunits, DmKu70 or DmKu80...
  11. Mishra M, Sharma A, Shukla A, Pragya P, Murthy R, de Pomerai D, et al. Transcriptomic analysis provides insights on hexavalent chromium induced DNA double strand breaks and their possible repair in midgut cells of Drosophila melanogaster larvae. Mutat Res. 2013;747-748:28-39 pubmed publisher
  12. Lankenau D, Gloor G. In vivo gap repair in Drosophila: a one-way street with many destinations. Bioessays. 1998;20:317-27 pubmed
    ..This review summarizes results that provide new insights into the process of gap repair in Drosophila and outline some recent experiments that demonstrate the power of the gene targeting technique. ..
  13. Sutcliffe J, Brehm A. Of flies and men; p53, a tumour suppressor. FEBS Lett. 2004;567:86-91 pubmed
    ..In addition, studying p53 in Drosophila provides an opportunity to learn about the evolution of tumour suppressors. Here, we will discuss what is known about Drosophila p53 in relation to human p53. ..
  14. Pastink A, Eeken J, Lohman P. Genomic integrity and the repair of double-strand DNA breaks. Mutat Res. 2001;480-481:37-50 pubmed
    ..This review summarizes our current knowledge about DSB-repair with emphasis on recent progress in understanding the precise biochemical activities of individual proteins involved. ..
  15. Chiolo I, Minoda A, Colmenares S, Polyzos A, Costes S, Karpen G. Double-strand breaks in heterochromatin move outside of a dynamic HP1a domain to complete recombinational repair. Cell. 2011;144:732-44 pubmed publisher
    ..We propose that the spatial and temporal control of DSB repair in heterochromatin safeguards genome stability by preventing aberrant exchanges between repeats. ..
  16. Wu L, Hickson I. Molecular biology. DNA ends ReQ-uire attention. Science. 2001;292:229-30 pubmed
  17. Staveley B, Heslip T, Hodgetts R, Bell J. Protected P-element termini suggest a role for inverted-repeat-binding protein in transposase-induced gap repair in Drosophila melanogaster. Genetics. 1995;139:1321-9 pubmed
    ..This sequence is known to bind the inverted-repeat-binding protein (IRBP). We propose that the IRBP may act to preserve the P-element ends when transposition produces a double-strand gap...
  18. Boutanaev A, Mikhaylova L, Nurminsky D. Up-regulation of the Ku heterodimer in Drosophila testicular cyst cells. FEBS Lett. 2007;581:1707-15 pubmed
    ..Abundance of Ku in the cyst cell cytoplasm suggests the role for Ku subunits in the regulation of sperm individualization. ..
  19. Janssen A, Breuer G, Brinkman E, van der Meulen A, Borden S, van Steensel B, et al. A single double-strand break system reveals repair dynamics and mechanisms in heterochromatin and euchromatin. Genes Dev. 2016;30:1645-57 pubmed publisher
    ..This direct analysis reveals important insights into heterochromatin DSB repair in animal tissues and provides a foundation for further explorations of repair mechanisms in different chromatin domains. ..
  20. Beall E, Admon A, Rio D. A Drosophila protein homologous to the human p70 Ku autoimmune antigen interacts with the P transposable element inverted repeats. Proc Natl Acad Sci U S A. 1994;91:12681-5 pubmed
    ..Biochemical studies have identified a cellular non-P element-encoded DNA binding protein, termed the inverted repeat binding protein (IRBP), that specifically interacts with the outer half of the 31-bp terminal inverted repeats...
  21. White T, Lambowitz A. The retrohoming of linear group II intron RNAs in Drosophila melanogaster occurs by both DNA ligase 4-dependent and -independent mechanisms. PLoS Genet. 2012;8:e1002534 pubmed publisher
    ..The DNA repair polymerase ? plays a crucial role in both pathways. Surprisingly, however, mutations in Ku70, which functions in capping chromosome ends during NHEJ, have only moderate, possibly indirect effects, suggesting ..
  22. Rio D, Rubin G. Identification and purification of a Drosophila protein that binds to the terminal 31-base-pair inverted repeats of the P transposable element. Proc Natl Acad Sci U S A. 1988;85:8929-33 pubmed
    ..The site to which binding occurs is included in a region absolutely required for P element transposition, suggesting that this binding protein may be a cellular factor involved in P element transposition. ..
  23. Mitsis P, Wensink P. Purification and properties of yolk protein factor I, a sequence-specific DNA-binding protein from Drosophila melanogaster. J Biol Chem. 1989;264:5195-202 pubmed
    We report the purification and some of the biochemical properties of yolk protein factor I (YPF1). This protein binds to a specific site in the yolk protein 1 gene (yp1) of Drosophila melanogaster...
  24. Lee Y, Langley C. Long-term and short-term evolutionary impacts of transposable elements on Drosophila. Genetics. 2012;192:1411-32 pubmed publisher
  25. Wang Z, Lin H. The division of Drosophila germline stem cells and their precursors requires a specific cyclin. Curr Biol. 2005;15:328-33 pubmed
    ..Our results indicate that stem cells may use specific cell cycle regulators for their division. ..
  26. Nicholas H, Brookfield J. The Drosophila melanogaster Ku70 coding sequence is wild-type in mus309 mutants. Genetica. 2002;114:293-6 pubmed
    Drosophila melanogaster mus309 mutations have been identified as being in the Ku70 gene, encoding one subunit of the DNA-dependent protein kinase...