NCBI Logo
GEO Logo
   NCBI > GEO > Accession DisplayHelp Not logged in | LoginHelp
GEO help: Mouse over screen elements for information.
          Go
Series GSE124382 Query DataSets for GSE124382
Status Public on Dec 27, 2018
Title DNA re-replication is susceptible to nucleotide level mutagenesis
Organism Saccharomyces cerevisiae
Experiment type Genome variation profiling by array
Summary The sources of genome instability, a hallmark of cancer, remain incompletely understood. One potential source is DNA re-replication, which arises when the mechanisms that prevent re-initiation of replication origins within a single cell cycle are compromised. Using the budding yeast Saccharomyces cerevisiae, we previously showed that DNA re-replication is extremely potent at inducing gross chromosomal alterations and that this arises in part because of the susceptibility of re-replication forks to break. Here, we examine the ability of DNA re-replication to induce nucleotide level mutations. During normal replication these mutations are restricted by three overlapping error avoidance mechanisms: the nucleotide selectivity of replicative polymerases, their proofreading activity, and mismatch repair. Using lys2InsEA14, a frameshift reporter that is poorly proofread, we show that re-replication induces up to a 30x higher rate of frameshift mutations and that this mutagenesis is due to passage of the re-replication fork, not secondary to re-replication fork breakage. Re-replication can also induce comparable rates of frameshift and base substitution mutations in a more general mutagenesis reporter CAN1, when the proofreading activity of DNA polymerase ε is inactivated. Finally, we show that the induction of lys2InsEA14 frameshift mutations by re-replication is dependent on mismatch repair. These results suggest that the mismatch repair associated with re-replication is attenuated, although at most sequences DNA polymerase proofreading provides enough error correction to mitigate the mutagenic consequences. Thus, re-replication can facilitate nucleotide level mutagenesis in addition to inducing gross chromosomal alterations, broadening its potential role in genome instability.
 
Overall design The arrays in this series are primary comparative genomic hybridizations to determine genomic changes after re-replication or other genomic stresses. Genomic DNA was purified from reference Saccharomyces cerevisiae cells or survivors of re-replication or other genomic stresses, differentially labeled with Cy3 and Cy5, and competitively hybridized to a spotted microarray containing ORF and intergenic PCR products. Cy5/Cy3 ratios are normalized so that the average ratio of all elements was 1. A small number of the arrays were used to determine the extent and location of re-replication under different conditions. For those, genomic DNA was purified from non-replicating and re-replicating cells. Series contains a total of 12 hybridizations. 90% of the re-replicating DNA preparation and 1 µg of the reference DNA were labeled, respectively, with Cy3 and Cy5 fluorescent dye (Fisher Scientific 45-001-270). Arrays were then scanned using an Axon Scanner 4B. GenePix Pro6.0 and BatchReplicationAnalyzer4.2 were then used to generate copy number information across the genome.
More information on the strains used in this study is available in the file Strains_GEO_submission.xlsx available at the foot of this page.
 
Contributor(s) Bui DT, Li JJ
Citation(s) 31028114
Submission date Dec 26, 2018
Last update date Jun 20, 2019
Contact name duyen Bui
E-mail(s) duyenthanh.bui@ucsf.edu
Phone 6073793347
Organization name UCSF
Lab Joachim Li
Street address 600 16th street
City San Francisco
State/province CALIFORNIA
ZIP/Postal code 94107
Country USA
 
Platforms (1)
GPL3412 Li UCSF yeast 14062 v1.0
Samples (12)
GSM3530763 Positive_control_genomic_changes_due_to_re-replication_at_ChrIV 567 kb_1
GSM3530764 Positive_control_genomic_changes_due_to_re-replication_at_ChrIV 567 kb_2
GSM3530765 genomic_changes_due_to_re-replication_at_ChrIV 567 kb_1
Relations
BioProject PRJNA511875

Download family Format
SOFT formatted family file(s) SOFTHelp
MINiML formatted family file(s) MINiMLHelp
Series Matrix File(s) TXTHelp

Supplementary file Size Download File type/resource
GSE124382_RAW.tar 16.8 Mb (http)(custom) TAR (of GPR)
GSE124382_Strains_GEO_submission.xlsx 16.1 Kb (ftp)(http) XLSX
Processed data included within Sample table

| NLM | NIH | GEO Help | Disclaimer | Accessibility |
NCBI Home NCBI Search NCBI SiteMap