Ku-dependent and Ku-independent end-joining pathways lead to chromosomal rearrangements during double-strand break repair in Saccharomyces cerevisiae - PubMed (original) (raw)

Ku-dependent and Ku-independent end-joining pathways lead to chromosomal rearrangements during double-strand break repair in Saccharomyces cerevisiae

Xin Yu et al. Genetics. 2003 Mar.

Abstract

Chromosomal double-strand breaks (DSBs) can be repaired by either homology-dependent or homology-independent pathways. Nonhomologous repair mechanisms have been relatively less well studied, despite their potential importance in generating chromosomal rearrangements. We have developed a Saccharomyces cerevisiae-based assay to identify and characterize homology-independent chromosomal rearrangements associated with repair of a unique DSB generated within an engineered URA3 gene. Approximately 1% of successfully repaired cells have accompanying chromosomal rearrangements consisting of large insertions, deletions, aberrant gene conversions, or other more complex changes. We have analyzed rearrangements in isogenic wild-type, rad52, yku80, and rad52 yku80 strains, to determine the types of events that occur in the presence or absence of these key repair proteins. Deletions were found in all strain backgrounds, but insertions were dependent upon the presence of Yku80p. A rare RAD52- and YKU80-independent form of deletion was present in all strains. These events were characterized by long one-sided deletions (up to 13 kb) and extensive imperfect overlapping sequences (7-22 bp) at the junctions. Our results demonstrate that the frequency and types of repair events depend on the specific genetic context. This approach can be applied to a number of problems associated with chromosome stability.

PubMed Disclaimer

References

    1. Curr Biol. 2001 Oct 16;11(20):1611-7 - PubMed
    1. Genes Dev. 2001 Nov 15;15(22):3005-12 - PubMed
    1. Nature. 2001 Dec 6;414(6864):666-9 - PubMed
    1. Mol Cell. 2001 Nov;8(5):1105-15 - PubMed
    1. Genes Dev. 2001 Dec 15;15(24):3237-42 - PubMed

Publication types

MeSH terms

Substances

LinkOut - more resources