19
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Systematic Analysis of the DNA Damage Response Network in Telomere Defective Budding Yeast

      research-article

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Functional telomeres are critically important to eukaryotic genetic stability. Scores of proteins and pathways are known to affect telomere function. Here, we report a series of related genome-wide genetic interaction screens performed on budding yeast cells with acute or chronic telomere defects. Genetic interactions were examined in cells defective in Cdc13 and Stn1, affecting two components of CST, a single stranded DNA (ssDNA) binding complex that binds telomeric DNA. For comparison, genetic interactions were also examined in cells with defects in Rfa3, affecting the major ssDNA binding protein, RPA, which has overlapping functions with CST at telomeres. In more complex experiments, genetic interactions were measured in cells lacking EXO1 or RAD9, affecting different aspects of the DNA damage response, and containing a cdc13-1 induced telomere defect. Comparing fitness profiles across these data sets helps build a picture of the specific responses to different types of dysfunctional telomeres. The experiments show that each context reveals different genetic interactions, consistent with the idea that each genetic defect causes distinct molecular defects. To help others engage with the large volumes of data, the data are made available via two interactive web-based tools: Profilyzer and DIXY. One particularly striking genetic interaction observed was that the chk1∆ mutation improved fitness of cdc13-1 exo1∆ cells more than other checkpoint mutations ( ddc1∆, rad9∆, rad17∆, and rad24∆), whereas, in cdc13-1 cells, the effects of all checkpoint mutations were similar. We show that this can be explained by Chk1 stimulating resection—a new function for Chk1 in the eukaryotic DNA damage response network.

          Most cited references37

          • Record: found
          • Abstract: found
          • Article: not found

          Telomerase mutations in families with idiopathic pulmonary fibrosis.

          Idiopathic pulmonary fibrosis is progressive and often fatal; causes of familial clustering of the disease are unknown. Germ-line mutations in the genes hTERT and hTR, encoding telomerase reverse transcriptase and telomerase RNA, respectively, cause autosomal dominant dyskeratosis congenita, a rare hereditary disorder associated with premature death from aplastic anemia and pulmonary fibrosis. To test the hypothesis that familial idiopathic pulmonary fibrosis may be caused by short telomeres, we screened 73 probands from the Vanderbilt Familial Pulmonary Fibrosis Registry for mutations in hTERT and hTR. Six probands (8%) had heterozygous mutations in hTERT or hTR; mutant telomerase resulted in short telomeres. Asymptomatic subjects with mutant telomerase also had short telomeres, suggesting that they may be at risk for the disease. We did not identify any of the classic features of dyskeratosis congenita in five of the six families. Mutations in the genes encoding telomerase components can appear as familial idiopathic pulmonary fibrosis. Our findings support the idea that pathways leading to telomere shortening are involved in the pathogenesis of this disease. Copyright 2007 Massachusetts Medical Society.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Telomeres and aging.

            Telomeres play a central role in cell fate and aging by adjusting the cellular response to stress and growth stimulation on the basis of previous cell divisions and DNA damage. At least a few hundred nucleotides of telomere repeats must "cap" each chromosome end to avoid activation of DNA repair pathways. Repair of critically short or "uncapped" telomeres by telomerase or recombination is limited in most somatic cells and apoptosis or cellular senescence is triggered when too many "uncapped" telomeres accumulate. The chance of the latter increases as the average telomere length decreases. The average telomere length is set and maintained in cells of the germline which typically express high levels of telomerase. In somatic cells, telomere length is very heterogeneous but typically declines with age, posing a barrier to tumor growth but also contributing to loss of cells with age. Loss of (stem) cells via telomere attrition provides strong selection for abnormal and malignant cells, a process facilitated by the genome instability and aneuploidy triggered by dysfunctional telomeres. The crucial role of telomeres in cell turnover and aging is highlighted by patients with 50% of normal telomerase levels resulting from a mutation in one of the telomerase genes. Short telomeres in such patients are implicated in a variety of disorders including dyskeratosis congenita, aplastic anemia, pulmonary fibrosis, and cancer. Here the role of telomeres and telomerase in human aging and aging-associated diseases is reviewed.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Synthetic genetic array analysis in Saccharomyces cerevisiae.

              Synthetic lethality occurs when the combination of two mutations leads to an inviable organism. Screens for synthetic lethal genetic interactions have been used extensively to identify genes whose products buffer one another or impinge on the same essential pathway. For the yeast Saccharomyces cerevisiae, we developed a method termed Synthetic Genetic Array (SGA) analysis, which offers an efficient approach for the systematic construction of double mutants and enables a global analysis of synthetic lethal genetic interactions. In a typical SGA screen, a query mutation is crossed to an ordered array of approx 5000 viable gene deletion mutants (representing approximately 80% of all yeast genes) such that meiotic progeny harboring both mutations can be scored for fitness defects. This array-based approach automates yeast genetic analysis in general and can be easily adapted for a number of different screens, including genetic suppression, plasmid shuffling, dosage lethality, or suppression.
                Bookmark

                Author and article information

                Journal
                G3 (Bethesda)
                Genetics
                G3: Genes, Genomes, Genetics
                G3: Genes, Genomes, Genetics
                G3: Genes, Genomes, Genetics
                G3: Genes|Genomes|Genetics
                Genetics Society of America
                2160-1836
                25 May 2017
                July 2017
                : 7
                : 7
                : 2375-2389
                Affiliations
                [* ]Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, United Kingdom
                []Institute of Cancer and Genetics, School of Medicine, Cardiff University, CF14 4XN, United Kingdom
                []The Gurdon Institute and Department of Zoology, University of Cambridge, CB2 1QN, United Kingdom
                [§ ]School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom
                Author notes
                [1]

                These authors contributed equally to this work.

                [2 ]Corresponding author: Institute for Cell and Molecular Biosciences, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK. E-mail: David.Lydall@ 123456ncl.ac.uk
                Author information
                http://orcid.org/0000-0002-4186-8506
                http://orcid.org/0000-0003-2478-085X
                Article
                GGG_042283
                10.1534/g3.117.042283
                5499144
                28546384
                b936820a-14eb-4067-993d-33f14f60368b
                Copyright © 2017 Holstein et al.

                This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License ( http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

                History
                : 12 April 2017
                : 19 May 2017
                Page count
                Figures: 7, Tables: 3, Equations: 0, References: 42, Pages: 15
                Categories
                Investigations

                Genetics
                dna damage,telomere,yeast
                Genetics
                dna damage, telomere, yeast

                Comments

                Comment on this article