Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

0

Band-array detection of chromosomal rearrangements in diploid yeast cells exposed to ionizing radiation


ABSTRACT: At the organismal level, genome rearrangements are usually deleterious and are often associated with disease. Yet, on an evolutionary scale, they can be beneficial as they provide for rapid genetic diversification. DNA lesions, particularly double-strand breaks (DSBs), are sources of genome instability that can be rectified by various repair processes. Homologous recombination (HR) is highly effective at protecting the genome from DSBs and provides for accurate repair between sister chromatids and homologous chromosomes. Here we show that although random DSBs induced by ionizing radiation in yeast chromosomes are repaired efficiently by HR in G-2 diploid cells, rearrangements are frequent. The chromosome aberrations (ABs) primarily resulted from recombination between Ty retrotransposable elements, the most abundant class of dispersed repetitive DNAs in the genome, while some rearrangements involved other classes of repetitive DNA. Few, if any, of the ABs could be attributed to nonhomologous end-joining (NHEJ). We conclude that only those few DSBs that fall at or near the 3-5% of the genome composed of repetitive DNA elements are effective at generating rearrangements, while other lesions that appear in unique (single copy) sequences are correctly repaired. Thus, by successfully competing with repair that normally occurs between large homologous chromosomal DNAs, the combination of repetitive elements and DSBs provides genome plasticity and a rich source of evolutionary opportunities. Keywords: Band-array Each array in this series corresponds to the DNA of a yeast chromosomal band excised from a pulse-field gel (CHEF). Chromosomal aberrations identified in radiation survivors were analyzed by microarray to reveal which regions of the genome were present in the new chromosomes. The DNA enriched in the specific band appears in the arrays as continuos segments of spots with highly positive Log2 Red/Green ratios.

ORGANISM(S): Saccharomyces cerevisiae

SUBMITTER: Juan Lucas Argueso 

PROVIDER: E-GEOD-6991 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

altmetric image

Publications

Double-strand breaks associated with repetitive DNA can reshape the genome.

Argueso Juan Lucas JL   Westmoreland James J   Mieczkowski Piotr A PA   Gawel Malgorzata M   Petes Thomas D TD   Resnick Michael A MA  

Proceedings of the National Academy of Sciences of the United States of America 20080813 33


Ionizing radiation is an established source of chromosome aberrations (CAs). Although double-strand breaks (DSBs) are implicated in radiation-induced and other CAs, the underlying mechanisms are poorly understood. Here, we show that, although the vast majority of randomly induced DSBs in G(2) diploid yeast cells are repaired efficiently through homologous recombination (HR) between sister chromatids or homologous chromosomes, approximately 2% of all DSBs give rise to CAs. Complete molecular anal  ...[more]

Similar Datasets

2010-06-11 | E-GEOD-6984 | biostudies-arrayexpress
2010-05-06 | E-GEOD-14601 | biostudies-arrayexpress
2008-05-14 | E-GEOD-11425 | biostudies-arrayexpress
2010-05-18 | E-GEOD-16502 | biostudies-arrayexpress
2007-02-10 | GSE6991 | GEO
2007-02-08 | GSE6984 | GEO
2011-08-14 | E-GEOD-30073 | biostudies-arrayexpress
2012-05-10 | E-GEOD-37906 | biostudies-arrayexpress
2011-08-15 | GSE30073 | GEO
2022-06-01 | GSE205199 | GEO