The DNA-binding protein Hdf1p (a putative Ku homologue) is required for maintaining normal telomere length in Saccharomyces cerevisiae.
In mammalian cells, the Ku autoantigen is an end- binding DNA protein required for the repair of DNA breaks [Troelstra, C. and Jaspers, N.G.J. (1994) Curr. Biol., 4, 1149- 1151]. A yeast gene (HDF1) encoding a putative homologue of the 70 kDa subunit of Ku has recently been identified [Feldmann, H. and Winnacker, E. L. (1993) J. Biol. Chem., 268, 12895- 12900]. We find that hdf1 mutant strains have substantially shorter telomeres than wild-type strains. We speculate that Hdf1p may bind the natural ends of the chromosome, in addition to binding to the ends of broken DNA molecules. Strains with both an hdf1 mutation and a mutation in TEL 1 (a gene related to the human ataxia telangiectasia gene) have extremely short telomeres and grow slowly.
Porter
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SE
Department of Biology, University of North Carolina, Chapel Hill, 27599-3280, USA.
Greenwell
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PW
Ritchie
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KB
Petes
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TD
D034961:Antigens, Nuclear; D004265:DNA Helicases; D004268:DNA-Binding Proteins / Q000235:genetics*; D005656:Fungal Proteins / Q000235:genetics*; D000072200:Ku Autoantigen; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D016615:Telomere
D034961:Antigens, Nuclear; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins; C520769:YKU70 protein, S cerevisiae; C081647:high affinity DNA-binding factor, S cerevisiae; D004265:DNA Helicases; C106893:XRCC5 protein, human; C000606509:Xrcc6 protein, human; D000072200:Ku Autoantigen