ABSTRACT DNA double-strand breaks are repaired by homologous recombination or DNA end-joining, but the latter process often causes illegitimate recombination and chromosome rearrangements.

One of the factors involved in the end-joining process is Hdf1, a yeast homologue of Ku protein1,2,3,4. We used the yeast two-hybrid assay to show that Hdf1 interacts with Sir4, which is

involved in transcriptional silencing at telomeres and _HM_ loci5,6. Analyses of _sir4_ mutants showed that Sir4 is required for deletion by illegitimate recombination and DNA end-joining in

the pathway involving Hdf1. Sir2 and Sir3, but not Sir1, were also found to participate in these processes. Furthermore, mutations of the _SIR2_, _SIR3_ and _SIR4_ genes conferred increased

chromatin structure that is essential for the rejoining of DNA ends. Access through your institution Buy or subscribe This is a preview of subscription content, access via your institution

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MECHANISMS Article Open access 22 August 2024 THE IMPORTANCE OF DNAPKCS FOR BLUNT DNA END JOINING IS MAGNIFIED WHEN XLF IS WEAKENED Article Open access 27 June 2022 WIDESPREAD CHROMATIN

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264–285 (1948). Google Scholar  Download references ACKNOWLEDGEMENTS We thank S. Fields, S. M. Hollenberg, K. Johzuka, I. Kobayashi, A. Miyajima, J. Rine and J. W. Szostak for providing

plasmids and strains, and K. Johzuka for advice on the two-hybrid assay. This work was supported in part by grants to Y.T., J.K. and H.I. from the Ministry of Education, Science, Sports, and

Culture of Japan. Y.T. was supported by a postdoctoral fellowship of the Japan Society for the Promotion of Science. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Molecular

Biology, Institute of Medical Science, University of Tokyo, P.O. Takanawa, Tokyo, 108, Japan Yasumasa Tsukamoto, Jun-ichi Kato & Hideo Ikeda Authors * Yasumasa Tsukamoto View author

publications You can also search for this author inPubMed Google Scholar * Jun-ichi Kato View author publications You can also search for this author inPubMed Google Scholar * Hideo Ikeda

View author publications You can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to Hideo Ikeda. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT

THIS ARTICLE CITE THIS ARTICLE Tsukamoto, Y., Kato, Ji. & Ikeda, H. Silencing factors participate in DNA repair and recombination in _Saccharomyces cerevisiae_. _Nature_ 388, 900–903

(1997). https://doi.org/10.1038/42288 Download citation * Received: 25 March 1997 * Accepted: 12 June 1997 * Issue Date: 28 August 1997 * DOI: https://doi.org/10.1038/42288 SHARE THIS

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