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Genomic instability induced by lowered expression of POL3 in yeast

ABSTRACT: DNA replication stress (DRS)-linked genomic instability has emerged as an important factor driving cancer development. To understand the mechanisms of DRS-associated genomic instability and phenotypic evolution, we mapped chromosomal alterations in a yeast strain with lowered expression of the replicative DNA polymerase δ. At a whole-genome level, we identified both hotspots of mitotic recombination and chromosome-specific aneuploidy dependent on decreased levels of DNA polymerase δ. The high rate of chromosome loss is likely a reflection of reduced DNA repair capacity in strains with low levels of DNA polymerase. Most recombinogenic DNA lesions were introduced during S or G2 phase, presumably as a consequence of broken replication forks.

ORGANISM(S): Saccharomyces cerevisiae

PROVIDER: GSE78856 | GEO | 2016/03/03

SECONDARY ACCESSION(S): PRJNA314183

REPOSITORIES: GEO

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