The Yeast Chromatin Remodeler RSC Complex Facilitates End Joining Repair of DNA Double-Strand Breaks

Abstract

Repair of chromosome double-strand breaks (DSBs) is central to cell survival and genome integrity. Nonhomologous end joining (NHEJ) is the major cellular repair pathway that eliminates chromosome DSBs. Here we report our genetic screen that identified Rsc8 and Rsc30, subunits of the Saccharomyces cerevisiae chromatin remodeling complex RSC, as novel NHEJ factors. Deletion of RSC30 gene or the C-terminal truncation of RSC8 impairs NHEJ of a chromosome DSB created by HO endonuclease in vivo. rsc30Δ maintains a robust level of homologous recombination and the damage-induced cell cycle checkpoints. By chromatin immunoprecipitation, we show recruitment of RSC to a chromosome DSB with kinetics congruent with its involvement in NHEJ. Recruitment of RSC to a DSB depends on Mre11, Rsc30, and yKu70 proteins. Rsc1p and Rsc2p, two other RSC subunits, physically interact with yKu80p and Mre11p. The interaction of Rsc1p with Mre11p appears to be vital for survival from genotoxic stress. These results suggest that chromatin remodeling by RSC is important for NHEJ.

SUPPLEMENTAL MATERIAL

Supplemental material for this article may be found at http://mcb.asm.org/.

ACKNOWLEDGMENTS

We thank M. Carlson, S. Fields, D. Gottschling, J. Haber, K. Myung, B. Laurent, V. Lundblad, P. Sung, and A. Tomkinson for gifts of strains and reagents. We also thank J. Haber, M. K. Kim, B. Laurent, K. Myung, P. Sung, A. Tomkinson, and members of the S.E.L. laboratory for helpful discussion.

This work is funded by the Sydney Kimmel Foundation for Cancer Research and grants from NIH (ES12244, GM071011) to S.E.L.