Dna2 was first characterized in yeast as an essential gene encoding a protein with both helicase and endonuclease activities involved in maturation of Okazaki fragments during DNA replication. Dna2 also plays a role in double-strand break (DSB) repair by homolo-gous recombination. The respective contributions of its replication and/or repair functions toward cell viability and resistance to gen...

Cisplatin is commonly used in ovarian cancer chemotherapy, however, chemoresistance to cisplatin remains a great clinical challenge. Oncogenic transcriptional factor FOXM1 has been reported to be overexpressed in ovarian cancer. In this study, we aimed to investigate the potential role of FOXM1 in ovarian cancers with chemoresistance to cisplatin. Our results indicate that FOXM1 is upregulated ...

Dna2 was first characterized in yeast as an essential gene encoding a protein with both helicase and endonuclease activities involved in maturation of Okazaki fragments during DNA replication. Dna2 also plays a role in double-strand break (DSB) repair by homolo-gous recombination. The respective contributions of its replication and/or repair functions toward cell viability and resistance to gen...

DNA double-strand breaks that initiate meiotic recombination are exonucleolytically processed. This 5'→3' resection is a central, conserved feature of recombination but remains poorly understood. To address this lack, we mapped resection endpoints genome-wide at high resolution in Saccharomyces cerevisiae Full-length resection requires Exo1 exonuclease and the DSB-responsive kinase Tel1, but no...

The checkpoint kinase Rad53 is crucial to regulate DNA replication in the presence of replicative stress. Under conditions that interfere with the progression of replication forks, Rad53 prevents Exo1-dependent fork degradation. However, although EXO1 deletion avoids fork degradation in rad53 mutants, it does not suppress their sensitivity to the ribonucleotide reductase (RNR) inhibitor hydroxy...

Yeast exonuclease 1 (Exo1) is induced during meiosis and plays an important role in DNA homologous recombination and mismatch correction pathways. The human homolog, an 803-amino acid protein, shares 55% similarity to the yeast Exo1. In this report, we show that the enzyme functionally complements Saccharomyces cerevisiae Exo1 in recombination of direct repeat DNA fragments, UV resistance, and ...

Telomerase-defective budding yeast cells escape senescence by using homologous recombination to amplify telomeric or subtelomeric structures. Similarly, human cells that enter senescence can use homologous recombination for telomere maintenance, when telomerase cannot be activated. Although recombination proteins required to generate telomerase-independent survivors have been intensively studie...

The long noncoding telomeric repeat containing RNA (TERRA) is expressed at chromosome ends. TERRA upregulation upon experimental manipulation or in ICF (immunodeficiency, centromeric instability, facial anomalies) patients correlates with short telomeres. To study the mechanism of telomere length control by TERRA in Saccharomyces cerevisiae, we mapped the transcriptional start site of TERRA at ...

The yeast Exo1p nuclease functions in multiple cellular roles: resection of DNA ends generated during recombination, telomere stability, DNA mismatch repair, and expansion of gaps formed during the repair of UV-induced DNA damage. In this study, we performed high-resolution mapping of spontaneous and UV-induced recombination events between homologs in exo1 strains, comparing the results with sp...

Problems during DNA replication underlie genomic instability and drive malignant transformation. The DNA damage checkpoint stabilizes stalled replication forks thus counteracting aberrant fork transitions, DNA breaks and chromosomal rearrangements. We analyzed fork processing in checkpoint deficient cells by coupling psoralen crosslinking with replication intermediate two-dimensional gel analys...