51
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Konada L, Aricthota S, Vadla R, Haldar D. Fission Yeast Sirtuin Hst4 Functions in Preserving Genomic Integrity by Regulating Replisome Component Mcl1. Sci Rep 2018; 8:8496. [PMID: 29855479 PMCID: PMC5981605 DOI: 10.1038/s41598-018-26476-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 04/19/2018] [Indexed: 11/09/2022] Open
Abstract
The Schizosaccharomyces pombe sirtuin Hst4, functions in the maintenance of genome stability by regulating histone H3 lysine56 acetylation (H3K56ac) and promoting cell survival during replicative stress. However, its molecular function in DNA damage survival is unclear. Here, we show that hst4 deficiency in the fission yeast causes S phase delay and DNA synthesis defects. We identified a novel functional link between hst4 and the replisome component mcl1 in a suppressor screen aimed to identify genes that could restore the slow growth and Methyl methanesulphonate (MMS) sensitivity phenotypes of the hst4Δ mutant. Expression of the replisome component Mcl1 rescues hst4Δ phenotypes. Interestingly, hst4 and mcl1 show an epistatic interaction and suppression of hst4Δ phenotypes by mcl1 is H3K56 acetylation dependent. Furthermore, Hst4 was found to regulate the expression of mcl1. Finally, we show that hSIRT2 depletion results in decreased levels of And-1 (human orthologue of Mcl1), establishing the conservation of this mechanism. Moreover, on induction of replication stress (MMS treatment), Mcl1 levels decrease upon Hst4 down regulation. Our results identify a novel function of Hst4 in regulation of DNA replication that is dependent on H3K56 acetylation. Both SIRT2 and And-1 are deregulated in cancers. Therefore, these findings could be of therapeutic importance in future.
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Affiliation(s)
- Lahiri Konada
- Centre for DNA Fingerprinting and Diagnostics, Survey Nos. 728, 729, 730 & 734, Opposite Uppal Water Tank, Beside BSNL T E Building, Uppal, Ranga Reddy District, Hyderabad, 500039, India.,Graduate Studies, Manipal University, Manipal, India
| | - Shalini Aricthota
- Centre for DNA Fingerprinting and Diagnostics, Survey Nos. 728, 729, 730 & 734, Opposite Uppal Water Tank, Beside BSNL T E Building, Uppal, Ranga Reddy District, Hyderabad, 500039, India.,Graduate Studies, Manipal University, Manipal, India
| | - Raghavendra Vadla
- Centre for DNA Fingerprinting and Diagnostics, Survey Nos. 728, 729, 730 & 734, Opposite Uppal Water Tank, Beside BSNL T E Building, Uppal, Ranga Reddy District, Hyderabad, 500039, India.,Graduate Studies, Manipal University, Manipal, India
| | - Devyani Haldar
- Centre for DNA Fingerprinting and Diagnostics, Survey Nos. 728, 729, 730 & 734, Opposite Uppal Water Tank, Beside BSNL T E Building, Uppal, Ranga Reddy District, Hyderabad, 500039, India.
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52
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Rapid Nuclear Exclusion of Hcm1 in Aging Saccharomyces cerevisiae Leads to Vacuolar Alkalization and Replicative Senescence. G3-GENES GENOMES GENETICS 2018. [PMID: 29519938 PMCID: PMC5940150 DOI: 10.1534/g3.118.200161] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The yeast, Saccharomyces cerevisiae, like other higher eukaryotes, undergo a finite number of cell divisions before exiting the cell cycle due to the effects of aging. Here, we show that yeast aging begins with the nuclear exclusion of Hcm1 in young cells, resulting in loss of acidic vacuoles. Autophagy is required for healthy aging in yeast, with proteins targeted for turnover by autophagy directed to the vacuole. Consistent with this, vacuolar acidity is necessary for vacuolar function and yeast longevity. Using yeast genetics and immunofluorescence microscopy, we confirm that vacuolar acidity plays a critical role in cell health and lifespan, and is potentially maintained by a series of Forkhead Box (Fox) transcription factors. An interconnected transcriptional network involving the Fox proteins (Fkh1, Fkh2 and Hcm1) are required for transcription of v-ATPase subunits and vacuolar acidity. As cells age, Hcm1 is rapidly excluded from the nucleus in young cells, blocking the expression of Hcm1 targets (Fkh1 and Fkh2), leading to loss of v-ATPase gene expression, reduced vacuolar acidification, increased α-syn-GFP vacuolar accumulation, and finally, diminished replicative lifespan (RLS). Loss of vacuolar acidity occurs about the same time as Hcm1 nuclear exclusion and is conserved; we have recently demonstrated that lysosomal alkalization similarly contributes to aging in C. elegans following a transition from progeny producing to post-reproductive life. Our data points to a molecular mechanism regulating vacuolar acidity that signals the end of RLS when acidification is lost.
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53
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Jones SK, Spivey EC, Rybarski JR, Finkelstein IJ. A Microfluidic Device for Massively Parallel, Whole-lifespan Imaging of Single Fission Yeast Cells. Bio Protoc 2018; 8:e2783. [PMID: 29770351 DOI: 10.21769/bioprotoc.2783] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Whole-lifespan single-cell analysis has greatly increased our understanding of fundamental cellular processes such as cellular aging. To observe individual cells across their entire lifespan, all progeny must be removed from the growth medium, typically via manual microdissection. However, manual microdissection is laborious, low-throughput, and incompatible with fluorescence microscopy. Here, we describe assembly and operation of the multiplexed-Fission Yeast Lifespan Microdissector (multFYLM), a high-throughput microfluidic device for rapidly acquiring single-cell whole-lifespan imaging. multFYLM captures approximately one thousand rod-shaped fission yeast cells from up to six different genetic backgrounds or treatment regimens. The immobilized cells are fluorescently imaged for over a week, while the progeny cells are removed from the device. The resulting datasets yield high-resolution multi-channel images that record each cell's replicative lifespan. We anticipate that the multFYLM will be broadly applicable for single-cell whole-lifespan studies in the fission yeast (Schizosaccharomyces pombe) and other symmetrically-dividing unicellular organisms.
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Affiliation(s)
- Stephen K Jones
- Department of Molecular Biosciences and Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA.,Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, USA
| | - Eric C Spivey
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - James R Rybarski
- Department of Molecular Biosciences and Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA.,Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, USA
| | - Ilya J Finkelstein
- Department of Molecular Biosciences and Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA.,Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, USA
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54
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Simoneau A, Ricard É, Wurtele H. An interplay between multiple sirtuins promotes completion of DNA replication in cells with short telomeres. PLoS Genet 2018; 14:e1007356. [PMID: 29659581 PMCID: PMC5919697 DOI: 10.1371/journal.pgen.1007356] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 04/26/2018] [Accepted: 04/09/2018] [Indexed: 01/08/2023] Open
Abstract
The evolutionarily-conserved sirtuin family of histone deacetylases regulates a multitude of DNA-associated processes. A recent genome-wide screen conducted in the yeast Saccharomyces cerevisiae identified Yku70/80, which regulate nonhomologous end-joining (NHEJ) and telomere structure, as being essential for cell proliferation in the presence of the pan-sirtuin inhibitor nicotinamide (NAM). Here, we show that sirtuin-dependent deacetylation of both histone H3 lysine 56 and H4 lysine 16 promotes growth of yku70Δ and yku80Δ cells, and that the NAM sensitivity of these mutants is not caused by defects in DNA double-strand break repair by NHEJ, but rather by their inability to maintain normal telomere length. Indeed, our results indicate that in the absence of sirtuin activity, cells with abnormally short telomeres, e.g., yku70/80Δ or est1/2Δ mutants, present striking defects in S phase progression. Our data further suggest that early firing of replication origins at short telomeres compromises the cellular response to NAM- and genotoxin-induced replicative stress. Finally, we show that reducing H4K16ac in yku70Δ cells limits activation of the DNA damage checkpoint kinase Rad53 in response to replicative stress, which promotes usage of translesion synthesis and S phase progression. Our results reveal a novel interplay between sirtuin-mediated regulation of chromatin structure and telomere-regulating factors in promoting timely completion of S phase upon replicative stress.
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Affiliation(s)
- Antoine Simoneau
- Centre de recherche de l’Hôpital Maisonneuve-Rosemont, boulevard de l’Assomption, Montréal, Canada
- Programme de Biologie Moléculaire, Université de Montréal, Montréal, Canada
| | - Étienne Ricard
- Centre de recherche de l’Hôpital Maisonneuve-Rosemont, boulevard de l’Assomption, Montréal, Canada
- Programme de Biologie Moléculaire, Université de Montréal, Montréal, Canada
| | - Hugo Wurtele
- Centre de recherche de l’Hôpital Maisonneuve-Rosemont, boulevard de l’Assomption, Montréal, Canada
- Département de Médecine, Université de Montréal, Montréal, Canada
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55
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Deprez MA, Eskes E, Wilms T, Ludovico P, Winderickx J. pH homeostasis links the nutrient sensing PKA/TORC1/Sch9 ménage-à-trois to stress tolerance and longevity. MICROBIAL CELL 2018; 5:119-136. [PMID: 29487859 PMCID: PMC5826700 DOI: 10.15698/mic2018.03.618] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The plasma membrane H+-ATPase Pma1 and the vacuolar V-ATPase act in close harmony to tightly control pH homeostasis, which is essential for a vast number of physiological processes. As these main two regulators of pH are responsive to the nutritional status of the cell, it seems evident that pH homeostasis acts in conjunction with nutrient-induced signalling pathways. Indeed, both PKA and the TORC1-Sch9 axis influence the proton pumping activity of the V-ATPase and possibly also of Pma1. In addition, it recently became clear that the proton acts as a second messenger to signal glucose availability via the V-ATPase to PKA and TORC1-Sch9. Given the prominent role of nutrient signalling in longevity, it is not surprising that pH homeostasis has been linked to ageing and longevity as well. A first indication is provided by acetic acid, whose uptake by the cell induces toxicity and affects longevity. Secondly, vacuolar acidity has been linked to autophagic processes, including mitophagy. In agreement with this, a decline in vacuolar acidity was shown to induce mitochondrial dysfunction and shorten lifespan. In addition, the asymmetric inheritance of Pma1 has been associated with replicative ageing and this again links to repercussions on vacuolar pH. Taken together, accumulating evidence indicates that pH homeostasis plays a prominent role in the determination of ageing and longevity, thereby providing new perspectives and avenues to explore the underlying molecular mechanisms.
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Affiliation(s)
| | - Elja Eskes
- Functional Biology, KU Leuven, Leuven, Belgium
| | | | - Paula Ludovico
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
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56
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Abstract
As the popular adage goes, all diseases run into old age and almost all physiological changes are associated with alterations in gene expression, irrespective of whether they are causal or consequential. Therefore, the quest for mechanisms that delay ageing and decrease age-associated diseases has propelled researchers to unravel regulatory factors that lead to changes in chromatin structure and function, which ultimately results in deregulated gene expression. It is therefore essential to bring together literature, which until recently has investigated gene expression and chromatin independently. With advances in biomedical research and the emergence of epigenetic regulators as potential therapeutic targets, enhancing our understanding of mechanisms that 'derail' transcription and identification of causal genes/pathways during ageing will have a significant impact. In this context, this chapter aims to not only summarize the key features of age-associated changes in epigenetics and transcription, but also identifies gaps in the field and proposes aspects that need to be investigated in the future.
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57
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Shi Y, Wang H, Yan Y, Cao H, Liu X, Lin F, Lu J. Glycerol-3-Phosphate Shuttle Is Involved in Development and Virulence in the Rice Blast Fungus Pyricularia oryzae. FRONTIERS IN PLANT SCIENCE 2018; 9:687. [PMID: 29875789 PMCID: PMC5974175 DOI: 10.3389/fpls.2018.00687] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Accepted: 05/04/2018] [Indexed: 05/07/2023]
Abstract
The glycerol-3-phosphate (G-3-P) shuttle is an important pathway for delivery of cytosolic reducing equivalents into mitochondrial oxidative phosphorylation, and plays essential physiological roles in yeast, plants, and animals. However, its role has been unclear in filamentous and pathogenic fungi. Here, we characterize the function of the G-3-P shuttle in Pyricularia oryzae by genetic and molecular analyses. In P. oryzae, a glycerol-3-phosphate dehydrogenase 1 (PoGpd1) is involved in NO production, conidiation, and utilization of several carbon sources (pyruvate, sodium acetate, glutamate, and glutamine). A glycerol-3-phosphate dehydrogenase 2 (PoGpd2) is essential for glycerol utilization and fungal development. Deletion of PoGPD2 led to delayed aerial hyphal formation, accelerated aerial hyphal collapse, and reduced conidiation on complete medium (CM) under a light-dark cycle. Aerial mycelial surface hydrophobicity to water and Tween 20 was decreased in ΔPogpd2. Melanin synthesis genes required for cell wall construction and two transcription factor genes (COS1 and CONx2) required for conidiation and/or aerial hyphal differentiation were down-regulated in the aerial mycelia of ΔPogpd2 and ΔPogpd1. Culturing under continuous dark could complement the defects of aerial hyphal differentiation of ΔPogpd2 observed in a light-dark cycle. Two light-sensitive protein genes (PoSIR2 encoding an NAD+-dependent deacetylase and TRX2 encoding a thioredoxin 2) were up-regulated in ΔPogpd2 cultured on CM medium in a light-dark cycle. ΔPogpd2 showed an increased intracellular NAD+/NADH ratio and total NAD content, and alteration of intracellular ATP production. Culturing on minimal medium also could restore aerial hyphal differentiation of ΔPogpd2, which is deficient on CM medium in a light-dark cycle. Two glutamate synthesis genes, GDH1 and PoGLT1, which synthesize glutamate coupled with oxidation of NADH to NAD+, were significantly up-regulated in ΔPogpd2 in a light-dark cycle. Moreover, deletion of PoGpd1 or PoGpd2 led to reduced virulence of conidia or hyphae on rice. The glycerol-3-phosphate shuttle is involved in cellular redox, fungal development, and virulence in P. oryzae.
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Affiliation(s)
- Yongkai Shi
- State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Huan Wang
- State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Yuxin Yan
- State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Huijuan Cao
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Xiaohong Liu
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, China
| | - Fucheng Lin
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, China
| | - Jianping Lu
- State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou, China
- Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Zhejiang University, Hangzhou, China
- *Correspondence: Jianping Lu,
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58
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Mitochondrial form, function and signalling in aging. Biochem J 2017; 473:3421-3449. [PMID: 27729586 DOI: 10.1042/bcj20160451] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 06/17/2016] [Indexed: 02/07/2023]
Abstract
Aging is often accompanied by a decline in mitochondrial mass and function in different tissues. Additionally, cell resistance to stress is frequently found to be prevented by higher mitochondrial respiratory capacity. These correlations strongly suggest mitochondria are key players in aging and senescence, acting by regulating energy homeostasis, redox balance and signalling pathways central in these processes. However, mitochondria display a wide array of functions and signalling properties, and the roles of these different characteristics are still widely unexplored. Furthermore, differences in mitochondrial properties and responses between tissues and cell types, and how these affect whole body metabolism are also still poorly understood. This review uncovers aspects of mitochondrial biology that have an impact upon aging in model organisms and selected mammalian cells and tissues.
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59
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Arras SDM, Chitty JL, Wizrah MSI, Erpf PE, Schulz BL, Tanurdzic M, Fraser JA. Sirtuins in the phylum Basidiomycota: A role in virulence in Cryptococcus neoformans. Sci Rep 2017; 7:46567. [PMID: 28429797 PMCID: PMC5399365 DOI: 10.1038/srep46567] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 03/17/2017] [Indexed: 02/07/2023] Open
Abstract
Virulence of Cryptococcus neoformans is regulated by a range of transcription factors, and is also influenced by the acquisition of adaptive mutations during infection. Beyond the temporal regulation of virulence factor production by transcription factors and these permanent microevolutionary changes, heritable epigenetic modifications such as histone deacetylation may also play a role during infection. Here we describe the first comprehensive analysis of the sirtuin class of NAD+ dependent histone deacetylases in the phylum Basidiomycota, identifying five sirtuins encoded in the C. neoformans genome. Each sirtuin gene was deleted and a wide range of phenotypic tests performed to gain insight into the potential roles they play. Given the pleiotropic nature of sirtuins in other species, it was surprising that only two of the five deletion strains revealed mutant phenotypes in vitro. However, cryptic consequences of the loss of each sirtuin were identified through whole cell proteomics, and mouse infections revealed a role in virulence for SIR2, HST3 and HST4. The most intriguing phenotype was the repeated inability to complement mutant phenotypes through the reintroduction of the wild-type gene. These data support the model that regulation of sirtuin activity may be employed to enable a drastic alteration of the epigenetic landscape and virulence of C. neoformans.
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Affiliation(s)
- Samantha D M Arras
- Australian Infectious Diseases Research Centre, Queensland, Australia.,School of Chemistry &Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Jessica L Chitty
- Australian Infectious Diseases Research Centre, Queensland, Australia.,School of Chemistry &Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Maha S I Wizrah
- Australian Infectious Diseases Research Centre, Queensland, Australia.,School of Chemistry &Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Paige E Erpf
- Australian Infectious Diseases Research Centre, Queensland, Australia.,School of Chemistry &Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Benjamin L Schulz
- School of Chemistry &Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Milos Tanurdzic
- School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - James A Fraser
- Australian Infectious Diseases Research Centre, Queensland, Australia.,School of Chemistry &Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
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60
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Spivey EC, Jones SK, Rybarski JR, Saifuddin FA, Finkelstein IJ. An aging-independent replicative lifespan in a symmetrically dividing eukaryote. eLife 2017; 6:e20340. [PMID: 28139976 PMCID: PMC5332158 DOI: 10.7554/elife.20340] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 01/27/2017] [Indexed: 12/28/2022] Open
Abstract
The replicative lifespan (RLS) of a cell-defined as the number of cell divisions before death-has informed our understanding of the mechanisms of cellular aging. However, little is known about aging and longevity in symmetrically dividing eukaryotic cells because most prior studies have used budding yeast for RLS studies. Here, we describe a multiplexed fission yeast lifespan micro-dissector (multFYLM) and an associated image processing pipeline for performing high-throughput and automated single-cell micro-dissection. Using the multFYLM, we observe continuous replication of hundreds of individual fission yeast cells for over seventy-five generations. Surprisingly, cells die without the classic hallmarks of cellular aging, such as progressive changes in size, doubling time, or sibling health. Genetic perturbations and drugs can extend the RLS via an aging-independent mechanism. Using a quantitative model to analyze these results, we conclude that fission yeast does not age and that cellular aging and replicative lifespan can be uncoupled in a eukaryotic cell.
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Affiliation(s)
- Eric C Spivey
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
- Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, United States
| | - Stephen K Jones
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
- Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, United States
| | - James R Rybarski
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
| | - Fatema A Saifuddin
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
| | - Ilya J Finkelstein
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
- Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, United States
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, United States
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61
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HST1 increases replicative lifespan of a sir2Δ mutant in the absence of PDE2 in Saccharomyces cerevisiae. J Microbiol 2017; 55:123-129. [PMID: 28120189 DOI: 10.1007/s12275-017-6535-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 12/14/2016] [Accepted: 12/20/2016] [Indexed: 12/14/2022]
Abstract
Silent information regulator 2 (Sir2), which is the founding member of the sirtuin family of proteins, is a pro-longevity factor for replicative lifespan (RLS) in Saccharomyces cerevisiae. Sir2 is required for transcriptional silencing at mating type loci, telomeres, and rDNA loci. Sir2 also represses transcription of highly expressed growth-related genes, such as PMA1 and some ribosomal protein genes. Although the Sir2 paralogues Hst1, Hst2, Hst3, and Hst4 occur in S. cerevisiae, none of them could replace the transcriptional regulation of PMA1 by Sir2 in the wild type. In this study, we demonstrate that Hst1, the closest Sir2 paralogue, deacetylates the acetylated lysine 16 of histone H4 (H4K16Ac) and represses PMA1 transcription in the sir2Δ pde2Δ mutant. We further show that Hst1 plays a role in extending the RLS of the sir2Δ pde2Δ mutant. Collectively, our results suggest that Hst1 can substitute for Sir2 by deacetylating H4K16Ac only in the sir2Δ pde2Δ.
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62
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Peláez-Soto A, Fernández-Espinar MT, Roig P, Gil JV. Evaluation of the Ability of Polyphenol Extracts of Cocoa and Red Grape to Promote the Antioxidant Response in Yeast Using a Rapid Multiwell Assay. J Food Sci 2017; 82:324-332. [PMID: 28103406 DOI: 10.1111/1750-3841.13602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 11/18/2016] [Accepted: 11/26/2016] [Indexed: 12/19/2022]
Abstract
Saccharomyces cerevisiae has been used as a model organism to study the capacity of cocoa and red grape extracts to trigger an antioxidant response. A methodology adapted to microtiter plates has been developed to monitor yeast growth after culture preincubation with food ingredients and exposure to oxidative stress by hydrogen peroxide and menadione. This methodology proved effective in measuring the ability of cocoa and red grape extracts to promote an antioxidant response in yeast, and also the prospect of conducting dose-response studies. Additionally, the method has proven useful to perform studies with mutant strains lacking genes that may be related to the mechanism of action underlying the antioxidant properties. Thus, in a single assay, it is possible to elucidate the sensitivity of strains to oxidative stress, the ability of an ingredient to promote an antioxidant response, and the possible implication of certain genes. Results of assays using strain hst3Δ showed that the antioxidant protection provided by exposure to cocoa and red grape extracts was not present in the strain lacking gene HST3 when H2 O2 and menadione were used as oxidizing agents. This effect was previously reported for cocoa extract only, with H2 O2 as stressor. Moreover, the results showed that the mutant strain hst3Δ is more resistant to menadione and H2 O2 in the absence of preincubation with cocoa and red grape extract, hinting at the possible implication of sirtuin Hst3 in the antioxidant cellular response.
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Affiliation(s)
- Ana Peláez-Soto
- Área de Tecnología de Alimentos, Facultat de Farmàcia, Univ. de València, Avda. Vicent Andrés Estellés s/n., 46100, Burjassot, Valencia, Spain.,Depto. de Biotecnología de Alimentos, Insto. de Agroquímica y Tecnología de Alimentos, Consejo Superior de Investigaciones Científicas (CSIC), Av. Agustín Escardino, 7, 46980, Paterna, Valencia, Spain
| | - María Teresa Fernández-Espinar
- Depto. de Biotecnología de Alimentos, Insto. de Agroquímica y Tecnología de Alimentos, Consejo Superior de Investigaciones Científicas (CSIC), Av. Agustín Escardino, 7, 46980, Paterna, Valencia, Spain
| | - Patricia Roig
- Área de Tecnología de Alimentos, Facultat de Farmàcia, Univ. de València, Avda. Vicent Andrés Estellés s/n., 46100, Burjassot, Valencia, Spain.,Depto. de Biotecnología de Alimentos, Insto. de Agroquímica y Tecnología de Alimentos, Consejo Superior de Investigaciones Científicas (CSIC), Av. Agustín Escardino, 7, 46980, Paterna, Valencia, Spain
| | - José Vicente Gil
- Área de Tecnología de Alimentos, Facultat de Farmàcia, Univ. de València, Avda. Vicent Andrés Estellés s/n., 46100, Burjassot, Valencia, Spain.,Depto. de Biotecnología de Alimentos, Insto. de Agroquímica y Tecnología de Alimentos, Consejo Superior de Investigaciones Científicas (CSIC), Av. Agustín Escardino, 7, 46980, Paterna, Valencia, Spain
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63
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Molina-Serrano D, Schiza V, Demosthenous C, Stavrou E, Oppelt J, Kyriakou D, Liu W, Zisser G, Bergler H, Dang W, Kirmizis A. Loss of Nat4 and its associated histone H4 N-terminal acetylation mediates calorie restriction-induced longevity. EMBO Rep 2016; 17:1829-1843. [PMID: 27799288 PMCID: PMC5167350 DOI: 10.15252/embr.201642540] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 09/21/2016] [Accepted: 09/30/2016] [Indexed: 01/07/2023] Open
Abstract
Changes in histone modifications are an attractive model through which environmental signals, such as diet, could be integrated in the cell for regulating its lifespan. However, evidence linking dietary interventions with specific alterations in histone modifications that subsequently affect lifespan remains elusive. We show here that deletion of histone N‐alpha‐terminal acetyltransferase Nat4 and loss of its associated H4 N‐terminal acetylation (N‐acH4) extend yeast replicative lifespan. Notably, nat4Δ‐induced longevity is epistatic to the effects of calorie restriction (CR). Consistent with this, (i) Nat4 expression is downregulated and the levels of N‐acH4 within chromatin are reduced upon CR, (ii) constitutive expression of Nat4 and maintenance of N‐acH4 levels reduces the extension of lifespan mediated by CR, and (iii) transcriptome analysis indicates that nat4Δ largely mimics the effects of CR, especially in the induction of stress‐response genes. We further show that nicotinamidase Pnc1, which is typically upregulated under CR, is required for nat4Δ‐mediated longevity. Collectively, these findings establish histone N‐acH4 as a regulator of cellular lifespan that links CR to increased stress resistance and longevity.
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Affiliation(s)
| | - Vassia Schiza
- Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | | | - Emmanouil Stavrou
- Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - Jan Oppelt
- CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czech Republic.,National Centre for Biomolecular Research, Masaryk University, Brno, Czech Republic
| | - Dimitris Kyriakou
- Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - Wei Liu
- Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
| | - Gertrude Zisser
- Institut für Molekulare Biowissenschaften, Karl-Franzens-Universität, Graz, Austria
| | - Helmut Bergler
- Institut für Molekulare Biowissenschaften, Karl-Franzens-Universität, Graz, Austria
| | - Weiwei Dang
- Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
| | - Antonis Kirmizis
- Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
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Role of nutraceutical SIRT1 modulators in AMPK and mTOR pathway: Evidence of a synergistic effect. Nutrition 2016; 34:82-96. [PMID: 28063518 DOI: 10.1016/j.nut.2016.09.008] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 08/04/2016] [Accepted: 09/23/2016] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate the effect of different natural substances on SIRT1 expression and on AMPK and mTOR phosphorylation. Moreover, we investigated the presence of a synergistic effect between the substances. METHODS Human cervical carcinoma cells were seeded in 12-well plates, then incubated with the nine tested substances (resveratrol, quercetin, berberine, catechin, tyrosol, ferulic acid, niclosamide, curcumin, and malvidin) at different concentrations and left in incubation for 3, 6, and 24 h. The targeting proteins' expression and phosphorylation were evaluated by immunoblotting, and cytotoxicity tests were performed by CellTiter-Blue Cell Viability Assay. RESULTS No statistically significant decrease (P > 0.05) in the number of viable cells was found. The expression of SIRT1 was significantly increased in all experimental groups compared with the control group (P < 0.001). Instead, the simultaneous administration involved a significant and synergistic increase in the expression of SIRT1 for some but not all of the tested compounds. Finally, the individual administration of berberine, quercetin, ferulic acid, and tyrosol resulted in a statistically significant increase in AMPK activation and mTOR inhibition, whereas their associated administration did not reveal a synergistic effect. CONCLUSIONS Our results provide evidence that all compounds have the potential to stimulate SIRT1 and sustain the stimulating action of resveratrol on SIRT1, already widely reported in the literature. In this regard, we confirm the interaction of these substances also with the pathway of AMPK and mTOR, in support of the studies that highlight the importance of SIRT1/AMPK and mTOR pathway in many diseases.
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65
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Saad H, Cobb JA. A decade of understanding spatio-temporal regulation of DNA repair by the nuclear architecture. Biochem Cell Biol 2016; 94:433-440. [DOI: 10.1139/bcb-2016-0085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The nucleus is a hub for gene expression and is a highly organized entity. The nucleoplasm is heterogeneous, owing to the preferential localization of specific metabolic factors, which lead to the definition of nuclear compartments or bodies. The genome is organized into chromosome territories, as well as heterochromatin and euchromatin domains. Recent observations have indicated that nuclear organization is important for maintaining genomic stability. For example, nuclear organization has been implicated in stabilizing damaged DNA, repair-pathway choice, and in preventing chromosomal rearrangements. Over the past decade, several studies have revealed that dynamic changes in the nuclear architecture are important during double-strand break repair. Stemming from work in yeast, relocation of a damaged site prior to repair appears to be at least partially conserved in multicellular eukaryotes. In this review, we will discuss genome and nucleoplasm architecture, particularly the importance of the nuclear periphery in genome stability. We will also discuss how the site of relocation regulates repair-pathway choice.
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Affiliation(s)
- Hicham Saad
- Southern Alberta Cancer Research Institute, Departments of Biochemistry & Molecular Biology and Oncology, Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Cumming School of Medicine; University of Calgary; 3330 Hospital Drive N.W., Calgary, AB T2N 4N1, Canada
- Southern Alberta Cancer Research Institute, Departments of Biochemistry & Molecular Biology and Oncology, Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Cumming School of Medicine; University of Calgary; 3330 Hospital Drive N.W., Calgary, AB T2N 4N1, Canada
| | - Jennifer A. Cobb
- Southern Alberta Cancer Research Institute, Departments of Biochemistry & Molecular Biology and Oncology, Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Cumming School of Medicine; University of Calgary; 3330 Hospital Drive N.W., Calgary, AB T2N 4N1, Canada
- Southern Alberta Cancer Research Institute, Departments of Biochemistry & Molecular Biology and Oncology, Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Cumming School of Medicine; University of Calgary; 3330 Hospital Drive N.W., Calgary, AB T2N 4N1, Canada
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66
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Nicotinamide Suppresses the DNA Damage Sensitivity of Saccharomyces cerevisiae Independently of Sirtuin Deacetylases. Genetics 2016; 204:569-579. [PMID: 27527516 DOI: 10.1534/genetics.116.193524] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 08/15/2016] [Indexed: 11/18/2022] Open
Abstract
Nicotinamide is both a reaction product and an inhibitor of the conserved sirtuin family of deacetylases, which have been implicated in a broad range of cellular functions in eukaryotes from yeast to humans. Phenotypes observed following treatment with nicotinamide are most often assumed to stem from inhibition of one or more of these enzymes. Here, we used this small molecule to inhibit multiple sirtuins at once during treatment with DNA damaging agents in the Saccharomyces cerevisiae model system. Since sirtuins have been previously implicated in the DNA damage response, we were surprised to observe that nicotinamide actually increased the survival of yeast cells exposed to the DNA damage agent MMS. Remarkably, we found that enhanced resistance to MMS in the presence of nicotinamide was independent of all five yeast sirtuins. Enhanced resistance was also independent of the nicotinamide salvage pathway, which uses nicotinamide as a substrate to generate NAD+, and of a DNA damage-induced increase in the salvage enzyme Pnc1 Our data suggest a novel and unexpected function for nicotinamide that has broad implications for its use in the study of sirtuin biology across model systems.
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67
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Honigberg SM. Similar environments but diverse fates: Responses of budding yeast to nutrient deprivation. MICROBIAL CELL 2016; 3:302-328. [PMID: 27917388 PMCID: PMC5134742 DOI: 10.15698/mic2016.08.516] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Diploid budding yeast (Saccharomyces cerevisiae) can adopt one
of several alternative differentiation fates in response to nutrient limitation,
and each of these fates provides distinct biological functions. When different
strain backgrounds are taken into account, these various fates occur in response
to similar environmental cues, are regulated by the same signal transduction
pathways, and share many of the same master regulators. I propose that the
relationships between fate choice, environmental cues and signaling pathways are
not Boolean, but involve graded levels of signals, pathway activation and
master-regulator activity. In the absence of large differences between
environmental cues, small differences in the concentration of cues may be
reinforced by cell-to-cell signals. These signals are particularly essential for
fate determination within communities, such as colonies and biofilms, where fate
choice varies dramatically from one region of the community to another. The lack
of Boolean relationships between cues, signaling pathways, master regulators and
cell fates may allow yeast communities to respond appropriately to the wide
range of environments they encounter in nature.
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Affiliation(s)
- Saul M Honigberg
- Division of Cell Biology and Biophysics, University of Missouri-Kansas City, 5007 Rockhill Rd, Kansas City MO 64110, USA
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68
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Saccharomyces cerevisiae TORC1 Controls Histone Acetylation by Signaling Through the Sit4/PP6 Phosphatase to Regulate Sirtuin Deacetylase Nuclear Accumulation. Genetics 2016; 203:1733-46. [PMID: 27343235 PMCID: PMC4981274 DOI: 10.1534/genetics.116.188458] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 06/15/2016] [Indexed: 01/09/2023] Open
Abstract
The epigenome responds to changes in the extracellular environment, yet how this information is transmitted to the epigenetic regulatory machinery is unclear. Using a Saccharomyces cerevisiae yeast model, we demonstrate that target of rapamycin complex 1 (TORC1) signaling, which is activated by nitrogen metabolism and amino acid availability, promotes site-specific acetylation of histone H3 and H4 N-terminal tails by opposing the activity of the sirtuin deacetylases Hst3 and Hst4. TORC1 does so through suppression of the Tap42-regulated Sit4 (PP6) phosphatase complex, as sit4Δ rescues histone acetylation under TORC1-repressive conditions. We further demonstrate that TORC1 inhibition, and subsequent PP6 activation, causes a selective, rapid, nuclear accumulation of Hst4, which correlates with decreased histone acetylation. This increased Hst4 nuclear localization precedes an elevation in Hst4 protein expression, which is attributed to reduced protein turnover, suggesting that nutrient signaling through TORC1 may limit Hst4 nuclear accumulation to facilitate Hst4 degradation and maintain histone acetylation. This pathway is functionally relevant to TORC1 signaling since the stress sensitivity of a nonessential TORC1 mutant (tco89Δ) to hydroxyurea and arsenic can be reversed by combining tco89Δ with either hst3Δ, hst4Δ, or sit4Δ. Surprisingly, while hst3Δ or hst4Δ rescues the sensitivity tco89Δ has to low concentrations of the TORC1 inhibitor rapamycin, sit4Δ fails to do so. These results suggest Sit4 provides an additional function necessary for TORC1-dependent cell growth and proliferation. Collectively, this study defines a novel mechanism by which TORC1 suppresses a PP6-regulated sirtuin deacetylase pathway to couple nutrient signaling to epigenetic regulation.
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69
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Buck SW, Maqani N, Matecic M, Hontz RD, Fine RD, Li M, Smith JS. RNA Polymerase I and Fob1 contributions to transcriptional silencing at the yeast rDNA locus. Nucleic Acids Res 2016; 44:6173-84. [PMID: 27060141 PMCID: PMC5291248 DOI: 10.1093/nar/gkw212] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 03/21/2016] [Indexed: 11/29/2022] Open
Abstract
RNA polymerase II (Pol II)-transcribed genes embedded within the yeast rDNA locus are repressed through a Sir2-dependent process called ‘rDNA silencing’. Sir2 is recruited to the rDNA promoter through interactions with RNA polymerase I (Pol I), and to a pair of DNA replication fork block sites (Ter1 and Ter2) through interaction with Fob1. We utilized a reporter gene (mURA3) integrated adjacent to the leftmost rDNA gene to investigate localized Pol I and Fob1 functions in silencing. Silencing was attenuated by loss of Pol I subunits or insertion of an ectopic Pol I terminator within the adjacent rDNA gene. Silencing left of the rDNA array is naturally attenuated by the presence of only one intact Fob1 binding site (Ter2). Repair of the 2nd Fob1 binding site (Ter1) dramatically strengthens silencing such that it is no longer impacted by local Pol I transcription defects. Global loss of Pol I activity, however, negatively affects Fob1 association with the rDNA. Loss of Ter2 almost completely eliminates localized silencing, but is restored by artificially targeting Fob1 or Sir2 as Gal4 DNA binding domain fusions. We conclude that Fob1 and Pol I make independent contributions to establishment of silencing, though Pol I also reinforces Fob1-dependent silencing.
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Affiliation(s)
- Stephen W Buck
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Nazif Maqani
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Mirela Matecic
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Robert D Hontz
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Ryan D Fine
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Mingguang Li
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Jeffrey S Smith
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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L-carnosine enhanced reproductive potential of the Saccharomyces cerevisiae yeast growing on medium containing glucose as a source of carbon. Biogerontology 2016; 17:737-47. [PMID: 27040824 PMCID: PMC4933726 DOI: 10.1007/s10522-016-9645-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 03/30/2016] [Indexed: 01/04/2023]
Abstract
Carnosine is an endogenous dipeptide composed of β-alanine and L-histidine, which occurs in vertebrates, including humans. It has a number of favorable properties including buffering, chelating, antioxidant, anti-glycation and anti-aging activities. In our study we used the Saccharomyces cerevisiae yeast as a model organism to examine the impact of L-carnosine on the cell lifespan. We demonstrated that L-carnosine slowed down the growth and decreased the metabolic activity of cells as well as prolonged their generation time. On the other hand, it allowed for enhancement of the yeast reproductive potential and extended its reproductive lifespan. These changes may be a result of the reduced mitochondrial membrane potential and decreased ATP content in the yeast cells. However, due to reduction of the post-reproductive lifespan, L-carnosine did not have an influence on the total lifespan of yeast. In conclusion, L-carnosine does not extend the total lifespan of S. cerevisiae but rather it increases the yeast's reproductive capacity by increasing the number of daughter cells produced.
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Simoneau A, Ricard É, Weber S, Hammond-Martel I, Wong LH, Sellam A, Giaever G, Nislow C, Raymond M, Wurtele H. Chromosome-wide histone deacetylation by sirtuins prevents hyperactivation of DNA damage-induced signaling upon replicative stress. Nucleic Acids Res 2016; 44:2706-26. [PMID: 26748095 PMCID: PMC4824096 DOI: 10.1093/nar/gkv1537] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 12/24/2015] [Indexed: 12/13/2022] Open
Abstract
The Saccharomyces cerevisiae genome encodes five sirtuins (Sir2 and Hst1-4), which constitute a conserved family of NAD-dependent histone deacetylases. Cells lacking any individual sirtuin display mild growth and gene silencing defects. However, hst3Δ hst4Δ double mutants are exquisitely sensitive to genotoxins, and hst3Δ hst4Δ sir2Δmutants are inviable. Our published data also indicate that pharmacological inhibition of sirtuins prevents growth of several fungal pathogens, although the biological basis is unclear. Here, we present genome-wide fitness assays conducted with nicotinamide (NAM), a pan-sirtuin inhibitor. Our data indicate that NAM treatment causes yeast to solicit specific DNA damage response pathways for survival, and that NAM-induced growth defects are mainly attributable to inhibition of Hst3 and Hst4 and consequent elevation of histone H3 lysine 56 acetylation (H3K56ac). Our results further reveal that in the presence of constitutive H3K56ac, the Slx4 scaffolding protein and PP4 phosphatase complex play essential roles in preventing hyperactivation of the DNA damage-response kinase Rad53 in response to spontaneous DNA damage caused by reactive oxygen species. Overall, our data support the concept that chromosome-wide histone deacetylation by sirtuins is critical to mitigate growth defects caused by endogenous genotoxins.
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Affiliation(s)
- Antoine Simoneau
- Maisonneuve-Rosemont Hospital Research Center, 5415 Assomption boulevard, Montreal, H1T 2M4, Canada Molecular biology program, Université de Montréal, P.O. Box 6128, Succursale Centre-ville, Montreal, H3C 3J7, Canada
| | - Étienne Ricard
- Maisonneuve-Rosemont Hospital Research Center, 5415 Assomption boulevard, Montreal, H1T 2M4, Canada Molecular biology program, Université de Montréal, P.O. Box 6128, Succursale Centre-ville, Montreal, H3C 3J7, Canada
| | - Sandra Weber
- Institute for Research in Immunology and Cancer, Université de Montréal, P.O. Box 6128, Succursale Centre-Ville, Montreal, H3C 3J7, Canada
| | - Ian Hammond-Martel
- Maisonneuve-Rosemont Hospital Research Center, 5415 Assomption boulevard, Montreal, H1T 2M4, Canada Molecular biology program, Université de Montréal, P.O. Box 6128, Succursale Centre-ville, Montreal, H3C 3J7, Canada
| | - Lai Hong Wong
- Department of Pharmaceutical Sciences, University of British Columbia, Vancouver, V6T 1Z3, Canada
| | - Adnane Sellam
- Infectious Diseases Research Centre-CRI, CHU de Québec Research Center (CHUQ), Université Laval, Québec, G1V 4G2, Canada Department of Microbiology-Infectious Disease and Immunology, Faculty of Medicine, Université Laval, Québec, G1V 0A6, Canada
| | - Guri Giaever
- Department of Pharmaceutical Sciences, University of British Columbia, Vancouver, V6T 1Z3, Canada
| | - Corey Nislow
- Department of Pharmaceutical Sciences, University of British Columbia, Vancouver, V6T 1Z3, Canada
| | - Martine Raymond
- Institute for Research in Immunology and Cancer, Université de Montréal, P.O. Box 6128, Succursale Centre-Ville, Montreal, H3C 3J7, Canada Department of Biochemistry and Molecular Medicine, Université de Montréal, C.P. 6128, Succursale Centre-ville, Montréal, H3C 3J7, Canada
| | - Hugo Wurtele
- Maisonneuve-Rosemont Hospital Research Center, 5415 Assomption boulevard, Montreal, H1T 2M4, Canada Department of Medicine, Université de Montréal, Montreal, H3T 1J4, Canada
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Choy JS, Qadri B, Henry L, Shroff K, Bifarin O, Basrai MA. A Genome-Wide Screen with Nicotinamide to Identify Sirtuin-Dependent Pathways in Saccharomyces cerevisiae. G3 (BETHESDA, MD.) 2015; 6:485-94. [PMID: 26646153 PMCID: PMC4751566 DOI: 10.1534/g3.115.022244] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 11/29/2015] [Indexed: 01/08/2023]
Abstract
Sirtuins are evolutionarily conserved NAD-dependent deacetylases that catalyze the cleavage of NAD(+) into nicotinamide (NAM), which can act as a pan-sirtuin inhibitor in unicellular and multicellular organisms. Sirtuins regulate processes such as transcription, DNA damage repair, chromosome segregation, and longevity extension in yeast and metazoans. The founding member of the evolutionarily conserved sirtuin family, SIR2, was first identified in budding yeast. Subsequent studies led to the identification of four yeast SIR2 homologs HST1, HST2, HST3, and HST4. Understanding the downstream physiological consequences of inhibiting sirtuins can be challenging since most studies focus on single or double deletions of sirtuins, and mating defects in SIR2 deletions hamper genome-wide screens. This represents an important gap in our knowledge of how sirtuins function in highly complex biological processes such as aging, metabolism, and chromosome segregation. In this report, we used a genome-wide screen to explore sirtuin-dependent processes in Saccharomyces cerevisiae by identifying deletion mutants that are sensitive to NAM. We identified 55 genes in total, 36 of which have not been previously reported to be dependent on sirtuins. We find that genome stability pathways are particularly vulnerable to loss of sirtuin activity. Here, we provide evidence that defects in sister chromatid cohesion renders cells sensitive to growth in the presence of NAM. The results of our screen provide a broad view of the biological pathways sensitive to inhibition of sirtuins, and advance our understanding of the function of sirtuins and NAD(+) biology.
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Affiliation(s)
- John S Choy
- Department of Biology, The Catholic University of America, Washington, D.C. 20064
| | - Bayan Qadri
- Department of Biology, The Catholic University of America, Washington, D.C. 20064
| | - Leah Henry
- Department of Biology, The Catholic University of America, Washington, D.C. 20064
| | - Kunal Shroff
- Department of Biology, The Catholic University of America, Washington, D.C. 20064
| | - Olatomiwa Bifarin
- Department of Biology, The Catholic University of America, Washington, D.C. 20064
| | - Munira A Basrai
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892
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73
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Zhou H, Jiang S, Chen J, Su SB. Suberoylanilide hydroxamic acid suppresses inflammation-induced neovascularization. Can J Physiol Pharmacol 2015; 92:879-85. [PMID: 25272091 DOI: 10.1139/cjpp-2014-0117] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Histone deacetylases (HDACs) regulate gene transcription by modifying the acetylation of histone and nonhistone proteins. Deregulated expression of HDACs has been implicated in tumorigenesis and angiogenesis. In this study, we examined the effect of suberoylanilide hydroxamic acid (SAHA), a potent inhibitor of HDACs, on inflammatory corneal angiogenesis. In a mouse model of alkali-induced corneal neovascularization (CNV), topical application of SAHA to the injured corneas attenuated CNV. In addition, in vivo treatment with SAHA downregulated the expression of the pro-angiogenic factors vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), transforming growth factor beta 1 (TGFβ1), and epidermal growth factor (EGF), but upregulated the expression of the anti-angiogenic factors thrombospondin (TSP)-1, TSP-2, and ADAMTS-1 in the injured corneas. Furthermore, SAHA inhibited the expression of pro-angiogenic factors, migration, proliferation, and tube formation by human microvascular endothelial cells (HEMC-1) in vitro. These data indicate that SAHA has therapeutic potential for CNV.
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Affiliation(s)
- Hongyan Zhou
- a The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Sun Yat-sen University, 54 S Xianlie Road, Guangzhou 510060, China
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74
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Kamei Y, Tai A, Dakeyama S, Yamamoto K, Inoue Y, Kishimoto Y, Ohara H, Mukai Y. Transcription factor genes essential for cell proliferation and replicative lifespan in budding yeast. Biochem Biophys Res Commun 2015; 463:351-6. [PMID: 26022127 DOI: 10.1016/j.bbrc.2015.05.067] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Accepted: 05/17/2015] [Indexed: 11/18/2022]
Abstract
Many of the lifespan-related genes have been identified in eukaryotes ranging from the yeast to human. However, there is limited information available on the longevity genes that are essential for cell proliferation. Here, we investigated whether the essential genes encoding DNA-binding transcription factors modulated the replicative lifespan of Saccharomyces cerevisiae. Heterozygous diploid knockout strains for FHL1, RAP1, REB1, and MCM1 genes showed significantly short lifespan. (1)H-nuclear magnetic resonance analysis indicated a characteristic metabolic profile in the Δfhl1/FHL1 mutant. These results strongly suggest that FHL1 regulates the transcription of lifespan related metabolic genes. Thus, heterozygous knockout strains could be the potential materials for discovering further novel lifespan genes.
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Affiliation(s)
- Yuka Kamei
- Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan
| | - Akiko Tai
- Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan
| | - Shota Dakeyama
- Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan
| | - Kaori Yamamoto
- Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan
| | - Yamato Inoue
- Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan
| | - Yoshifumi Kishimoto
- Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan
| | - Hiroya Ohara
- Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan
| | - Yukio Mukai
- Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan.
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75
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Jung PP, Christian N, Kay DP, Skupin A, Linster CL. Protocols and programs for high-throughput growth and aging phenotyping in yeast. PLoS One 2015; 10:e0119807. [PMID: 25822370 PMCID: PMC4379057 DOI: 10.1371/journal.pone.0119807] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 01/16/2015] [Indexed: 02/06/2023] Open
Abstract
In microorganisms, and more particularly in yeasts, a standard phenotyping approach consists in the analysis of fitness by growth rate determination in different conditions. One growth assay that combines high throughput with high resolution involves the generation of growth curves from 96-well plate microcultivations in thermostated and shaking plate readers. To push the throughput of this method to the next level, we have adapted it in this study to the use of 384-well plates. The values of the extracted growth parameters (lag time, doubling time and yield of biomass) correlated well between experiments carried out in 384-well plates as compared to 96-well plates or batch cultures, validating the higher-throughput approach for phenotypic screens. The method is not restricted to the use of the budding yeast Saccharomyces cerevisiae, as shown by consistent results for other species selected from the Hemiascomycete class. Furthermore, we used the 384-well plate microcultivations to develop and validate a higher-throughput assay for yeast Chronological Life Span (CLS), a parameter that is still commonly determined by a cumbersome method based on counting "Colony Forming Units". To accelerate analysis of the large datasets generated by the described growth and aging assays, we developed the freely available software tools GATHODE and CATHODE. These tools allow for semi-automatic determination of growth parameters and CLS behavior from typical plate reader output files. The described protocols and programs will increase the time- and cost-efficiency of a number of yeast-based systems genetics experiments as well as various types of screens.
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Affiliation(s)
- Paul P. Jung
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Nils Christian
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Daniel P. Kay
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Alexander Skupin
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
- National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, California, United States of America
| | - Carole L. Linster
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
- * E-mail:
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Lamoth F, Juvvadi PR, Steinbach WJ. Histone deacetylase inhibition as an alternative strategy against invasive aspergillosis. Front Microbiol 2015; 6:96. [PMID: 25762988 PMCID: PMC4329796 DOI: 10.3389/fmicb.2015.00096] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 01/26/2015] [Indexed: 01/07/2023] Open
Abstract
Invasive aspergillosis (IA) is a life-threatening infection due to Aspergillus fumigatus and other Aspergillus spp. Drugs targeting the fungal cell membrane (triazoles, amphotericin B) or cell wall (echinocandins) are currently the sole therapeutic options against IA. Their limited efficacy and the emergence of resistance warrant the identification of new antifungal targets. Histone deacetylases (HDACs) are enzymes responsible of the deacetylation of lysine residues of core histones, thus controlling chromatin remodeling and transcriptional activation. HDACs also control the acetylation and activation status of multiple non-histone proteins, including the heat shock protein 90 (Hsp90), an essential molecular chaperone for fungal virulence and antifungal resistance. This review provides an overview of the different HDACs in Aspergillus spp. as well as their respective contribution to total HDAC activity, fungal growth, stress responses, and virulence. The potential of HDAC inhibitors, currently under development for cancer therapy, as novel alternative antifungal agents against IA is discussed.
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Affiliation(s)
- Frédéric Lamoth
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center , Durham, NC, USA ; Infectious Diseases Service, Department of Medicine, Lausanne University Hospital , Lausanne, Switzerland ; Institute of Microbiology, Lausanne University Hospital , Lausanne, Switzerland
| | - Praveen R Juvvadi
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center , Durham, NC, USA
| | - William J Steinbach
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center , Durham, NC, USA ; Department of Molecular Genetics and Microbiology, Duke University Medical Center , Durham, NC, USA
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77
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van Deventer S, Menendez-Benito V, van Leeuwen F, Neefjes J. N-terminal acetylation and replicative age affect proteasome localization and cell fitness during aging. J Cell Sci 2015; 128:109-17. [PMID: 25413350 PMCID: PMC4282048 DOI: 10.1242/jcs.157354] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 11/05/2014] [Indexed: 01/05/2023] Open
Abstract
Specific degradation of proteins is essential for virtually all cellular processes and is carried out predominantly by the proteasome. The proteasome is important for clearance of damaged cellular proteins. Damaged proteins accumulate over time and excess damaged proteins can aggregate and induce the death of old cells. In yeast, the localization of the proteasome changes dramatically during aging, possibly in response to altered proteasome activity requirements. We followed two key parameters of this process: the distribution of proteasomes in nuclear and cytosolic compartments, and the formation of cytoplasmic aggregate-like structures called proteasome storage granules (PSGs). Whereas replicative young cells efficiently relocalized proteasomes from the nucleus to the cytoplasm and formed PSGs, replicative old cells were less efficient in relocalizing the proteasome and had less PSGs. By using a microscopy-based genome-wide screen, we identified genetic factors involved in these processes. Both relocalization of the proteasome and PSG formation were affected by two of the three N-acetylation complexes. These N-acetylation complexes also had different effects on the longevity of cells, indicating that each N-acetylation complex has different roles in proteasome location and aging.
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Affiliation(s)
- Sjoerd van Deventer
- Division of Cell Biology, Netherlands Cancer Institute and Netherlands Proteomics Center, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
| | - Victoria Menendez-Benito
- Division of Cell Biology, Netherlands Cancer Institute and Netherlands Proteomics Center, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
| | - Fred van Leeuwen
- Division of Gene Regulation, Netherlands Cancer Institute and Netherlands Proteomics Center, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
| | - Jacques Neefjes
- Division of Cell Biology, Netherlands Cancer Institute and Netherlands Proteomics Center, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
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78
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Downey M, Johnson JR, Davey NE, Newton BW, Johnson TL, Galaang S, Seller CA, Krogan N, Toczyski DP. Acetylome profiling reveals overlap in the regulation of diverse processes by sirtuins, gcn5, and esa1. Mol Cell Proteomics 2014; 14:162-76. [PMID: 25381059 DOI: 10.1074/mcp.m114.043141] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Although histone acetylation and deacetylation machineries (HATs and HDACs) regulate important aspects of cell function by targeting histone tails, recent work highlights that non-histone protein acetylation is also pervasive in eukaryotes. Here, we use quantitative mass-spectrometry to define acetylations targeted by the sirtuin family, previously implicated in the regulation of non-histone protein acetylation. To identify HATs that promote acetylation of these sites, we also performed this analysis in gcn5 (SAGA) and esa1 (NuA4) mutants. We observed strong sequence specificity for the sirtuins and for each of these HATs. Although the Gcn5 and Esa1 consensus sequences are entirely distinct, the sirtuin consensus overlaps almost entirely with that of Gcn5, suggesting a strong coordination between these two regulatory enzymes. Furthermore, by examining global acetylation in an ada2 mutant, which dissociates Gcn5 from the SAGA complex, we found that a subset of Gcn5 targets did not depend on an intact SAGA complex for targeting. Our work provides a framework for understanding how HAT and HDAC enzymes collaborate to regulate critical cellular processes related to growth and division.
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Affiliation(s)
- Michael Downey
- From the ‡Department of Biochemistry and Biophysics, University of California, San Francisco, 1450 3rd Street, San Francisco, CA, 94158;
| | - Jeffrey R Johnson
- §Cellular and Molecular Pharmacology, University of California, San Francisco, 1700 4th Street, QB3, San Francisco, CA, 94158
| | - Norman E Davey
- ¶Department of Physiology and Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94158
| | - Billy W Newton
- §Cellular and Molecular Pharmacology, University of California, San Francisco, 1700 4th Street, QB3, San Francisco, CA, 94158
| | - Tasha L Johnson
- §Cellular and Molecular Pharmacology, University of California, San Francisco, 1700 4th Street, QB3, San Francisco, CA, 94158
| | - Shastyn Galaang
- From the ‡Department of Biochemistry and Biophysics, University of California, San Francisco, 1450 3rd Street, San Francisco, CA, 94158
| | - Charles A Seller
- From the ‡Department of Biochemistry and Biophysics, University of California, San Francisco, 1450 3rd Street, San Francisco, CA, 94158
| | - Nevan Krogan
- §Cellular and Molecular Pharmacology, University of California, San Francisco, 1700 4th Street, QB3, San Francisco, CA, 94158
| | - David P Toczyski
- From the ‡Department of Biochemistry and Biophysics, University of California, San Francisco, 1450 3rd Street, San Francisco, CA, 94158
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79
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Protein acetylation and acetyl coenzyme a metabolism in budding yeast. EUKARYOTIC CELL 2014; 13:1472-83. [PMID: 25326522 DOI: 10.1128/ec.00189-14] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Cells sense and appropriately respond to the physical conditions and availability of nutrients in their environment. This sensing of the environment and consequent cellular responses are orchestrated by a multitude of signaling pathways and typically involve changes in transcription and metabolism. Recent discoveries suggest that the signaling and transcription machineries are regulated by signals which are derived from metabolism and reflect the metabolic state of the cell. Acetyl coenzyme A (CoA) is a key metabolite that links metabolism with signaling, chromatin structure, and transcription. Acetyl-CoA is produced by glycolysis as well as other catabolic pathways and used as a substrate for the citric acid cycle and as a precursor in synthesis of fatty acids and steroids and in other anabolic pathways. This central position in metabolism endows acetyl-CoA with an important regulatory role. Acetyl-CoA serves as a substrate for lysine acetyltransferases (KATs), which catalyze the transfer of acetyl groups to the epsilon-amino groups of lysines in histones and many other proteins. Fluctuations in the concentration of acetyl-CoA, reflecting the metabolic state of the cell, are translated into dynamic protein acetylations that regulate a variety of cell functions, including transcription, replication, DNA repair, cell cycle progression, and aging. This review highlights the synthesis and homeostasis of acetyl-CoA and the regulation of transcriptional and signaling machineries in yeast by acetylation.
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80
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Kang WK, Kim YH, Kim BS, Kim JY. Growth phase-dependent roles of Sir2 in oxidative stress resistance and chronological lifespan in yeast. J Microbiol 2014; 52:652-8. [PMID: 24997552 DOI: 10.1007/s12275-014-4173-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 05/07/2014] [Accepted: 05/07/2014] [Indexed: 01/07/2023]
Abstract
Silent Information Regulator 2 (Sir2), a conserved NAD(+)-dependent histone deacetylase, has been implicated as one of the key factors in regulating stress response and longevity. Here, we report that the role of Sir2 in oxidative stress resistance and chronological lifespan is dependent on growth phase in yeast. In exponential phase, sir2Δ cells were more resistant to H2O2 stress and had a longer chronological lifespan than wild type. By contrast, in post-diauxic phase, sir2Δ cells were less resistant to H2O2 stress and had a shorter chronological lifespan than wild type cells. Similarly, the expression of antioxidant genes, which are essential to cope with oxidative stress, was regulated by Sir2 in a growth phase-dependent manner. Collectively, our findings highlight the importance of the metabolic state of the cell in determining whether Sir2 can protect against or accelerate cellular aging of yeast.
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Affiliation(s)
- Woo Kyu Kang
- Department of Microbiology and Molecular Biology, College of Bioscience and Biotechnology, Chungnam National University, Daejeon, 305-764, Republic of Korea
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81
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Giancaspero TA, Dipalo E, Miccolis A, Boles E, Caselle M, Barile M. Alteration of ROS homeostasis and decreased lifespan in S. cerevisiae elicited by deletion of the mitochondrial translocator FLX1. BIOMED RESEARCH INTERNATIONAL 2014; 2014:101286. [PMID: 24895546 PMCID: PMC4033422 DOI: 10.1155/2014/101286] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 03/20/2014] [Accepted: 04/01/2014] [Indexed: 01/15/2023]
Abstract
This paper deals with the control exerted by the mitochondrial translocator FLX1, which catalyzes the movement of the redox cofactor FAD across the mitochondrial membrane, on the efficiency of ATP production, ROS homeostasis, and lifespan of S. cerevisiae. The deletion of the FLX1 gene resulted in respiration-deficient and small-colony phenotype accompanied by a significant ATP shortage and ROS unbalance in glycerol-grown cells. Moreover, the flx1Δ strain showed H2O2 hypersensitivity and decreased lifespan. The impaired biochemical phenotype found in the flx1Δ strain might be justified by an altered expression of the flavoprotein subunit of succinate dehydrogenase, a key enzyme in bioenergetics and cell regulation. A search for possible cis-acting consensus motifs in the regulatory region upstream SDH1-ORF revealed a dozen of upstream motifs that might respond to induced metabolic changes by altering the expression of Flx1p. Among these motifs, two are present in the regulatory region of genes encoding proteins involved in flavin homeostasis. This is the first evidence that the mitochondrial flavin cofactor status is involved in controlling the lifespan of yeasts, maybe by changing the cellular succinate level. This is not the only case in which the homeostasis of redox cofactors underlies complex phenotypical behaviours, as lifespan in yeasts.
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Affiliation(s)
| | - Emilia Dipalo
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari “A. Moro”, Via Orabona 4, 70126 Bari, Italy
| | - Angelica Miccolis
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari “A. Moro”, Via Orabona 4, 70126 Bari, Italy
| | - Eckhard Boles
- Institute of Molecular Biosciences, Goethe University Frankfurt, Max-von-Laue Straße 9, 60438 Frankfurt am Main, Germany
| | - Michele Caselle
- Dipartimento di Fisica, Via P. Giuria 1, 10125 Torino, Italy
| | - Maria Barile
- Istituto di Biomembrane e Bioenergetica, CNR, Via Amendola 165/A, 70126 Bari, Italy
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari “A. Moro”, Via Orabona 4, 70126 Bari, Italy
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Sampaio-Marques B, Burhans WC, Ludovico P. Longevity pathways and maintenance of the proteome: the role of autophagy and mitophagy during yeast ageing. MICROBIAL CELL 2014; 1:118-127. [PMID: 28357232 PMCID: PMC5349200 DOI: 10.15698/mic2014.04.136] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Ageing is a complex and multi-factorial process that results in the progressive
accumulation of molecular alterations that disrupt different cellular functions.
The budding yeast Saccharomyces cerevisiae is an important
model organism that has significantly contributed to the identification of
conserved molecular and cellular determinants of ageing. The nutrient-sensing
pathways are well-recognized modulators of longevity from yeast to mammals, but
their downstream effectors and outcomes on different features of ageing process
are still poorly understood. A hypothesis that is attracting increased interest
is that one of the major functions of these “longevity pathways” is to
contribute to the maintenance of the proteome during ageing. In support of this
hypothesis, evidence shows that TOR/Sch9 and Ras/PKA pathways are important
regulators of autophagy that in turn are essential for healthy cellular ageing.
It is also well known that mitochondria homeostasis and function regulate
lifespan, but how mitochondrial dynamics, mitophagy and biogenesis are regulated
during ageing remains to be elucidated. This review describes recent findings
that shed light on how longevity pathways and metabolic status impact
maintenance of the proteome in both yeast ageing paradigms. These findings
demonstrate that yeast remain a powerful model system for elucidating these
relationships and their influence on ageing regulation.
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Affiliation(s)
- Belém Sampaio-Marques
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal. ; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - William C Burhans
- Dept. of Molecular and Cellular Biology, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Paula Ludovico
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal. ; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
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83
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Ganley ARD, Kobayashi T. Ribosomal DNA and cellular senescence: new evidence supporting the connection between rDNA and aging. FEMS Yeast Res 2014; 14:49-59. [DOI: 10.1111/1567-1364.12133] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 12/10/2013] [Accepted: 12/19/2013] [Indexed: 12/19/2022] Open
Affiliation(s)
- Austen R. D. Ganley
- Institute of Natural and Mathematical Sciences; Massey University; Auckland New Zealand
| | - Takehiko Kobayashi
- Division of Cytogenetics; National Institute of Genetics; Mishima Shizuoka Japan
- Department of Genetics; The Graduate University for Advanced Studies; SOKENDAI; Mishima Shizuoka Japan
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