1
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Tate JJ, Rai R, Cooper TG. TorC1 and nitrogen catabolite repression control of integrated GABA shunt and retrograde pathway gene expression. Yeast 2023; 40:318-332. [PMID: 36960709 PMCID: PMC10518031 DOI: 10.1002/yea.3849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 03/10/2023] [Accepted: 03/14/2023] [Indexed: 03/25/2023] Open
Abstract
Despite our detailed understanding of how the lower GABA shunt and retrograde genes are regulated, there is a paucity of validated information concerning control of GAD1, the glutamate decarboxylase gene which catalyzes the first reaction of the GABA shunt. Further, integration of glutamate degradation via the GABA shunt has not been investigated. Here, we show that while GAD1 shares a response to rapamycin-inhibition of the TorC1 kinase, it does so independently of the Gln3 and Gat1 NCR-sensitive transcriptional activators that mediate transcription of the lower GABA shunt genes. We also show that GABA shunt gene expression increases dramatically in response to nickel ions. The α-ketoglutarate needed for the GABA shunt to cycle, thereby producing reduced pyridine nucleotides, derives from the retrograde pathway as shown by a similar high increase in the retrograde reporter, CIT2 when nickel is present in the medium. These observations demonstrate high integration of the GABA shunt, retrograde, peroxisomal glyoxylate cycle, and β-oxidation pathways.
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Affiliation(s)
- Jennifer J. Tate
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, U.S.A
| | - Rajendra Rai
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, U.S.A
| | - Terrance G. Cooper
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, U.S.A
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2
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Caligaris M, Sampaio-Marques B, Hatakeyama R, Pillet B, Ludovico P, De Virgilio C, Winderickx J, Nicastro R. The Yeast Protein Kinase Sch9 Functions as a Central Nutrient-Responsive Hub That Calibrates Metabolic and Stress-Related Responses. J Fungi (Basel) 2023; 9:787. [PMID: 37623558 PMCID: PMC10455444 DOI: 10.3390/jof9080787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/20/2023] [Accepted: 07/24/2023] [Indexed: 08/26/2023] Open
Abstract
Yeast cells are equipped with different nutrient signaling pathways that enable them to sense the availability of various nutrients and adjust metabolism and growth accordingly. These pathways are part of an intricate network since most of them are cross-regulated and subject to feedback regulation at different levels. In yeast, a central role is played by Sch9, a protein kinase that functions as a proximal effector of the conserved growth-regulatory TORC1 complex to mediate information on the availability of free amino acids. However, recent studies established that Sch9 is more than a TORC1-effector as its activity is tuned by several other kinases. This allows Sch9 to function as an integrator that aligns different input signals to achieve accuracy in metabolic responses and stress-related molecular adaptations. In this review, we highlight the latest findings on the structure and regulation of Sch9, as well as its role as a nutrient-responsive hub that impacts on growth and longevity of yeast cells. Given that most key players impinging on Sch9 are well-conserved, we also discuss how studies on Sch9 can be instrumental to further elucidate mechanisms underpinning healthy aging in mammalians.
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Affiliation(s)
- Marco Caligaris
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland; (M.C.); (B.P.); (C.D.V.)
| | - Belém Sampaio-Marques
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (B.S.-M.); (P.L.)
- ICVS/3B’s-PT Government Associate Laboratory, 4806-909 Guimarães, Portugal
| | - Riko Hatakeyama
- Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK;
| | - Benjamin Pillet
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland; (M.C.); (B.P.); (C.D.V.)
| | - Paula Ludovico
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; (B.S.-M.); (P.L.)
- ICVS/3B’s-PT Government Associate Laboratory, 4806-909 Guimarães, Portugal
| | - Claudio De Virgilio
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland; (M.C.); (B.P.); (C.D.V.)
| | - Joris Winderickx
- Department of Biology, Functional Biology, KU Leuven, B-3001 Heverlee, Belgium;
| | - Raffaele Nicastro
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland; (M.C.); (B.P.); (C.D.V.)
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3
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Uvdal P, Shashkova S. The Effect of Calorie Restriction on Protein Quality Control in Yeast. Biomolecules 2023; 13:biom13050841. [PMID: 37238710 DOI: 10.3390/biom13050841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/30/2023] [Accepted: 05/01/2023] [Indexed: 05/28/2023] Open
Abstract
Initially, protein aggregates were regarded as a sign of a pathological state of the cell. Later, it was found that these assemblies are formed in response to stress, and that some of them serve as signalling mechanisms. This review has a particular focus on how intracellular protein aggregates are related to altered metabolism caused by different glucose concentrations in the extracellular environment. We summarise the current knowledge of the role of energy homeostasis signalling pathways in the consequent effect on intracellular protein aggregate accumulation and removal. This covers regulation at different levels, including elevated protein degradation and proteasome activity mediated by the Hxk2 protein, the enhanced ubiquitination of aberrant proteins through Torc1/Sch9 and Msn2/Whi2, and the activation of autophagy mediated through ATG genes. Finally, certain proteins form reversible biomolecular aggregates in response to stress and reduced glucose levels, which are used as a signalling mechanism in the cell, controlling major primary energy pathways related to glucose sensing.
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Affiliation(s)
- Petter Uvdal
- Department of Physics, University of Gothenburg, 405 30 Göteborg, Sweden
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4
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Leonov A, Feldman R, Piano A, Arlia-Ciommo A, Junio JAB, Orfanos E, Tafakori T, Lutchman V, Mohammad K, Elsaser S, Orfali S, Rajen H, Titorenko VI. Diverse geroprotectors differently affect a mechanism linking cellular aging to cellular quiescence in budding yeast. Oncotarget 2022; 13:918-943. [PMID: 35937500 PMCID: PMC9348708 DOI: 10.18632/oncotarget.28256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 07/01/2022] [Indexed: 11/25/2022] Open
Affiliation(s)
- Anna Leonov
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Rachel Feldman
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Amanda Piano
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | | | | | - Emmanuel Orfanos
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Tala Tafakori
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Vicky Lutchman
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Karamat Mohammad
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Sarah Elsaser
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Sandra Orfali
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Harshvardhan Rajen
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
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5
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Antiaging Effect of 4-N-Furfurylcytosine in Yeast Model Manifests through Enhancement of Mitochondrial Activity and ROS Reduction. Antioxidants (Basel) 2022; 11:antiox11050850. [PMID: 35624714 PMCID: PMC9137487 DOI: 10.3390/antiox11050850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/20/2022] [Accepted: 04/25/2022] [Indexed: 12/04/2022] Open
Abstract
Small compounds are a large group of chemicals characterized by various biological properties. Some of them also have antiaging potential, which is mainly attributed to their antioxidant activity. In this study, we examined the antiaging effect of 4-N-Furfurylcytosine (FC), a cytosine derivative belonging to a group of small compounds, on budding yeast Saccharomyces cerevisiae. We chose this yeast model as it is known to contain multiple conserved genes and mechanisms identical to that of humans and has been proven to be successful in aging research. The chronological lifespan assay performed in the study revealed that FC improved the viability of yeast cells in a concentration-dependent manner. Furthermore, enhanced mitochondrial activity, together with reduced intracellular ROS level, was observed in FC-treated yeast cells. The gene expression analysis confirmed that FC treatment resulted in the restriction of the TORC1 signaling pathway. These results indicate that FC has antiaging properties.
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6
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Odoh CK, Guo X, Arnone JT, Wang X, Zhao ZK. The role of NAD and NAD precursors on longevity and lifespan modulation in the budding yeast, Saccharomyces cerevisiae. Biogerontology 2022; 23:169-199. [PMID: 35260986 PMCID: PMC8904166 DOI: 10.1007/s10522-022-09958-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 02/16/2022] [Indexed: 11/26/2022]
Abstract
Molecular causes of aging and longevity interventions have witnessed an upsurge in the last decade. The resurgent interests in the application of small molecules as potential geroprotectors and/or pharmacogenomics point to nicotinamide adenine dinucleotide (NAD) and its precursors, nicotinamide riboside, nicotinamide mononucleotide, nicotinamide, and nicotinic acid as potentially intriguing molecules. Upon supplementation, these compounds have shown to ameliorate aging related conditions and possibly prevent death in model organisms. Besides being a molecule essential in all living cells, our understanding of the mechanism of NAD metabolism and its regulation remain incomplete owing to its omnipresent nature. Here we discuss recent advances and techniques in the study of chronological lifespan (CLS) and replicative lifespan (RLS) in the model unicellular organism Saccharomyces cerevisiae. We then follow with the mechanism and biology of NAD precursors and their roles in aging and longevity. Finally, we review potential biotechnological applications through engineering of microbial lifespan, and laid perspective on the promising candidature of alternative redox compounds for extending lifespan.
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Affiliation(s)
- Chuks Kenneth Odoh
- Laboratory of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Rd, Dalian, 116023, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Xiaojia Guo
- Laboratory of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Rd, Dalian, 116023, China
- Dalian Key Laboratory of Energy Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Rd, Dalian, 116023, China
| | - James T Arnone
- Department of Biology, William Paterson University, Wayne, NJ, 07470, USA
| | - Xueying Wang
- Laboratory of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Rd, Dalian, 116023, China
- Dalian Key Laboratory of Energy Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Rd, Dalian, 116023, China
| | - Zongbao K Zhao
- Laboratory of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Rd, Dalian, 116023, China.
- Dalian Key Laboratory of Energy Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Rd, Dalian, 116023, China.
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7
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Tate JJ, Marsikova J, Vachova L, Palkova Z, Cooper TG. Effects of abolishing Whi2 on the proteome and nitrogen catabolite repression-sensitive protein production. G3 (BETHESDA, MD.) 2022; 12:jkab432. [PMID: 35100365 PMCID: PMC9210300 DOI: 10.1093/g3journal/jkab432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 12/08/2021] [Indexed: 11/17/2022]
Abstract
In yeast physiology, a commonly used reference condition for many experiments, including those involving nitrogen catabolite repression (NCR), is growth in synthetic complete (SC) medium. Four SC formulations, SCCSH,1990, SCCSH,1994, SCCSH,2005, and SCME, have been used interchangeably as the nitrogen-rich medium of choice [Cold Spring Harbor Yeast Course Manuals (SCCSH) and a formulation in the methods in enzymology (SCME)]. It has been tacitly presumed that all of these formulations support equivalent responses. However, a recent report concluded that (i) TorC1 activity is downregulated by the lower concentration of primarily leucine in SCME relative to SCCSH. (ii) The Whi2-Psr1/2 complex is responsible for this downregulation. TorC1 is a primary nitrogen-responsive regulator in yeast. Among its downstream targets is control of NCR-sensitive transcription activators Gln3 and Gat1. They in turn control production of catabolic transporters and enzymes needed to scavenge poor nitrogen sources (e.g., Proline) and activate autophagy (ATG14). One of the reporters used in Chen et al. was an NCR-sensitive DAL80-GFP promoter fusion. This intrigued us because we expected minimal if any DAL80 expression in SC medium. Therefore, we investigated the source of the Dal80-GFP production and the proteomes of wild-type and whi2Δ cells cultured in SCCSH and SCME. We found a massive and equivalent reorientation of amino acid biosynthetic proteins in both wild-type and whi2Δ cells even though both media contained high overall concentrations of amino acids. Gcn2 appears to play a significant regulatory role in this reorientation. NCR-sensitive DAL80 expression and overall NCR-sensitive protein production were only marginally affected by the whi2Δ. In contrast, the levels of 58 proteins changed by an absolute value of log2 between 3 and 8 when Whi2 was abolished relative to wild type. Surprisingly, with only two exceptions could those proteins be related in GO analyses, i.e., GO terms associated with carbohydrate metabolism and oxidative stress after shifting a whi2Δ from SCCSH to SCME for 6 h. What was conspicuously missing were proteins related by TorC1- and NCR-associated GO terms.
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Affiliation(s)
- Jennifer J Tate
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Jana Marsikova
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 128 00 Prague, Czech Republic
| | - Libuse Vachova
- Institute of Microbiology of the Czech Academy of Sciences, BIOCEV, 142 20 Prague, Czech Republic
| | - Zdena Palkova
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 128 00 Prague, Czech Republic
| | - Terrance G Cooper
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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8
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Lei Y, Huang Y, Wen X, Yin Z, Zhang Z, Klionsky DJ. How Cells Deal with the Fluctuating Environment: Autophagy Regulation under Stress in Yeast and Mammalian Systems. Antioxidants (Basel) 2022; 11:antiox11020304. [PMID: 35204187 PMCID: PMC8868404 DOI: 10.3390/antiox11020304] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 01/28/2022] [Accepted: 01/31/2022] [Indexed: 12/04/2022] Open
Abstract
Eukaryotic cells frequently experience fluctuations of the external and internal environments, such as changes in nutrient, energy and oxygen sources, and protein folding status, which, after reaching a particular threshold, become a type of stress. Cells develop several ways to deal with these various types of stress to maintain homeostasis and survival. Among the cellular survival mechanisms, autophagy is one of the most critical ways to mediate metabolic adaptation and clearance of damaged organelles. Autophagy is maintained at a basal level under normal growing conditions and gets stimulated by stress through different but connected mechanisms. In this review, we summarize the advances in understanding the autophagy regulation mechanisms under multiple types of stress including nutrient, energy, oxidative, and ER stress in both yeast and mammalian systems.
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Affiliation(s)
- Yuchen Lei
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Yuxiang Huang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Xin Wen
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Zhangyuan Yin
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Zhihai Zhang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Daniel J. Klionsky
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
- Correspondence:
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9
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Wauters R, Britton SJ, Verstrepen KJ. Old yeasts, young beer-The industrial relevance of yeast chronological life span. Yeast 2021; 38:339-351. [PMID: 33978982 PMCID: PMC8252602 DOI: 10.1002/yea.3650] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/28/2021] [Accepted: 05/09/2021] [Indexed: 12/20/2022] Open
Abstract
Much like other living organisms, yeast cells have a limited life span, in terms of both the maximal length of time a cell can stay alive (chronological life span) and the maximal number of cell divisions it can undergo (replicative life span). Over the past years, intensive research revealed that the life span of yeast depends on both the genetic background of the cells and environmental factors. Specifically, the presence of stress factors, reactive oxygen species, and the availability of nutrients profoundly impact life span, and signaling cascades involved in the response to these factors, including the target of rapamycin (TOR) and cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathways, play a central role. Interestingly, yeast life span also has direct implications for its use in industrial processes. In beer brewing, for example, the inoculation of finished beer with live yeast cells, a process called "bottle conditioning" helps improve the product's shelf life by clearing undesirable carbonyl compounds such as furfural and 2-methylpropanal that cause staling. However, this effect depends on the reductive metabolism of living cells and is thus inherently limited by the cells' chronological life span. Here, we review the mechanisms underlying chronological life span in yeast. We also discuss how this insight connects to industrial observations and ultimately opens new routes towards superior industrial yeasts that can help improve a product's shelf life and thus contribute to a more sustainable industry.
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Affiliation(s)
- Ruben Wauters
- Laboratory for Systems BiologyVIB Center for MicrobiologyLeuvenBelgium
- CMPG Laboratory of Genetics and Genomics, Department M2SKU LeuvenLeuvenBelgium
| | - Scott J. Britton
- Research and DevelopmentDuvel MoortgatPuurs‐Sint‐AmandsBelgium
- International Centre for Brewing and Distilling, Institute of Biological Chemistry, Biophysics and Bioengineering, School of Engineering and Physical SciencesHeriot‐Watt UniversityEdinburghUK
| | - Kevin J. Verstrepen
- Laboratory for Systems BiologyVIB Center for MicrobiologyLeuvenBelgium
- CMPG Laboratory of Genetics and Genomics, Department M2SKU LeuvenLeuvenBelgium
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10
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Moura RD, Carvalho LM, Spagnol BAA, Carneiro T, Tosi Costa AC, Quadros ODF, Ventura JA, de Biasi RS, Fernandes AAR, Fernandes PMB. Difference between the cell wall roughnesses of mothers and daughters of Saccharomyces cerevisiae subjected to high pressure stress. Micron 2021; 147:103091. [PMID: 34090132 DOI: 10.1016/j.micron.2021.103091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/27/2021] [Accepted: 05/27/2021] [Indexed: 10/21/2022]
Abstract
High hydrostatic pressure (HHP) stress generates cellular responses similar to those to other stresses that yeasts endure in fermentation tanks. Structural and spatial compaction of molecules, as well as weakening and stretching of plasma membranes and cell walls, are often observed and have a significant influence on the fermentative process. Atomic force microscopy (AFM) yields accurate data on the morphological characteristics of yeast cell walls, providing important insights for the development of more productive yeast strains. Saccharomyces cerevisiae cell wall assessment using AFM in the intermittent contact reading mode using a silicon cantilever, before and after application of a pressure of 100 MPa for 30 min, demonstrated that mother and daughter cells have different responses. Daughter cells were more sensitive to the effects of HHP, presenting lower average Ra (arithmetic roughness), Rz (ten-point average roughness), and Rq (root-mean-square roughness) after exposure to high pressure. Better adaptation to stress in mother cells leads to higher cell wall resistance and, therefore, to better protection.
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Affiliation(s)
- Raissa D Moura
- Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, ES, 29040-090, Brazil
| | - Lauanda M Carvalho
- Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, ES, 29040-090, Brazil
| | - Brígida A A Spagnol
- Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, ES, 29040-090, Brazil
| | - Tarcio Carneiro
- Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, ES, 29040-090, Brazil
| | - Ane Catarine Tosi Costa
- Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, ES, 29040-090, Brazil
| | - Oeber de F Quadros
- Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, ES, 29040-090, Brazil
| | - José A Ventura
- Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, ES, 29040-090, Brazil; Instituto Capixaba de Pesquisa, Assistência Técnica e Extensão Rural, Vitória, ES, 29050-790, Brazil
| | | | - A Alberto R Fernandes
- Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, ES, 29040-090, Brazil
| | - Patricia M B Fernandes
- Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, ES, 29040-090, Brazil.
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11
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Tate JJ, Rai R, De Virgilio C, Cooper TG. N- and C-terminal Gln3-Tor1 interaction sites: one acting negatively and the other positively to regulate nuclear Gln3 localization. Genetics 2021; 217:iyab017. [PMID: 33857304 PMCID: PMC8049557 DOI: 10.1093/genetics/iyab017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 01/24/2021] [Indexed: 12/31/2022] Open
Abstract
Gln3 activates Nitrogen Catabolite Repression, NCR-sensitive expression of the genes required for Saccharomyces cerevisiae to scavenge poor nitrogen sources from its environment. The global TorC1 kinase complex negatively regulates nuclear Gln3 localization, interacting with an α-helix in the C-terminal region of Gln3, Gln3656-666. In nitrogen replete conditions, Gln3 is sequestered in the cytoplasm, whereas when TorC1 is down-regulated, in nitrogen restrictive conditions, Gln3 migrates into the nucleus. In this work, we show that the C-terminal Gln3-Tor1 interaction site is required for wild type, rapamycin-elicited, Sit4-dependent nuclear Gln3 localization, but not for its dephosphorylation. In fact, truncated Gln31-384 can enter the nucleus in the absence of Sit4 in both repressive and derepressive growth conditions. However, Gln31-384 can only enter the nucleus if a newly discovered second positively-acting Gln3-Tor1 interaction site remains intact. Importantly, the N- and C-terminal Gln3-Tor1 interaction sites function both autonomously and collaboratively. The N-terminal Gln3-Tor1 interaction site, previously designated Gln3URS contains a predicted α-helix situated within an unstructured coiled-coil region. Eight of the thirteen serine/threonine residues in the Gln3URS are dephosphorylated 3-15-fold with three of them by 10-15-fold. Substituting phosphomimetic aspartate for serine/threonine residues in the Gln3 URS abolishes the N-terminal Gln3-Tor1 interaction, rapamycin-elicited nuclear Gln3 localization, and ½ of the derepressed levels of nuclear Gln3 localization. Cytoplasmic Gln3 sequestration in repressive conditions, however, remains intact. These findings further deconvolve the mechanisms that achieve nitrogen-responsive transcription factor regulation downstream of TorC1.
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Affiliation(s)
- Jennifer J Tate
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Rajendra Rai
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | | | - Terrance G Cooper
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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12
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Mohammad K, Baratang Junio JA, Tafakori T, Orfanos E, Titorenko VI. Mechanisms that Link Chronological Aging to Cellular Quiescence in Budding Yeast. Int J Mol Sci 2020; 21:ijms21134717. [PMID: 32630624 PMCID: PMC7369985 DOI: 10.3390/ijms21134717] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 06/27/2020] [Accepted: 06/30/2020] [Indexed: 12/28/2022] Open
Abstract
After Saccharomyces cerevisiae cells cultured in a medium with glucose consume glucose, the sub-populations of quiescent and non-quiescent cells develop in the budding yeast culture. An age-related chronology of quiescent and non-quiescent yeast cells within this culture is discussed here. We also describe various hallmarks of quiescent and non-quiescent yeast cells. A complex aging-associated program underlies cellular quiescence in budding yeast. This quiescence program includes a cascade of consecutive cellular events orchestrated by an intricate signaling network. We examine here how caloric restriction, a low-calorie diet that extends lifespan and healthspan in yeast and other eukaryotes, influences the cellular quiescence program in S. cerevisiae. One of the main objectives of this review is to stimulate an exploration of the mechanisms that link cellular quiescence to chronological aging of budding yeast. Yeast chronological aging is defined by the length of time during which a yeast cell remains viable after its growth and division are arrested, and it becomes quiescent. We propose a hypothesis on how caloric restriction can slow chronological aging of S. cerevisiae by altering the chronology and properties of quiescent cells. Our hypothesis posits that caloric restriction delays yeast chronological aging by targeting four different processes within quiescent cells.
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13
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Differences in gene modulation in Saccharomyces cerevisiae indicate that maturity plays an important role in the high hydrostatic pressure stress response and resistance. Fungal Biol 2020; 124:440-446. [DOI: 10.1016/j.funbio.2019.11.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 11/21/2019] [Accepted: 11/27/2019] [Indexed: 01/24/2023]
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14
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Medkour Y, Mohammad K, Arlia-Ciommo A, Svistkova V, Dakik P, Mitrofanova D, Rodriguez MEL, Junio JAB, Taifour T, Escudero P, Goltsios FF, Soodbakhsh S, Maalaoui H, Simard É, Titorenko VI. Mechanisms by which PE21, an extract from the white willow Salix alba, delays chronological aging in budding yeast. Oncotarget 2019; 10:5780-5816. [PMID: 31645900 PMCID: PMC6791382 DOI: 10.18632/oncotarget.27209] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 08/27/2019] [Indexed: 01/05/2023] Open
Abstract
We have recently found that PE21, an extract from the white willow Salix alba, slows chronological aging and prolongs longevity of the yeast Saccharomyces cerevisiae more efficiently than any of the previously known pharmacological interventions. Here, we investigated mechanisms through which PE21 delays yeast chronological aging and extends yeast longevity. We show that PE21 causes a remodeling of lipid metabolism in chronologically aging yeast, thereby instigating changes in the concentrations of several lipid classes. We demonstrate that such changes in the cellular lipidome initiate three mechanisms of aging delay and longevity extension. The first mechanism through which PE21 slows aging and prolongs longevity consists in its ability to decrease the intracellular concentration of free fatty acids. This postpones an age-related onset of liponecrotic cell death promoted by excessive concentrations of free fatty acids. The second mechanism of aging delay and longevity extension by PE21 consists in its ability to decrease the concentrations of triacylglycerols and to increase the concentrations of glycerophospholipids within the endoplasmic reticulum membrane. This activates the unfolded protein response system in the endoplasmic reticulum, which then decelerates an age-related decline in protein and lipid homeostasis and slows down an aging-associated deterioration of cell resistance to stress. The third mechanisms underlying aging delay and longevity extension by PE21 consists in its ability to change lipid concentrations in the mitochondrial membranes. This alters certain catabolic and anabolic processes in mitochondria, thus amending the pattern of aging-associated changes in several key aspects of mitochondrial functionality.
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Affiliation(s)
- Younes Medkour
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Karamat Mohammad
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | | | - Veronika Svistkova
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Pamela Dakik
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Darya Mitrofanova
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | | | | | - Tarek Taifour
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Paola Escudero
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Fani-Fay Goltsios
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Sahar Soodbakhsh
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Hana Maalaoui
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Éric Simard
- Idunn Technologies Inc., Rosemere, Quebec J7A 4A5, Canada
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15
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Gulli J, Cook E, Kroll E, Rosebrock A, Caudy A, Rosenzweig F. Diverse conditions support near-zero growth in yeast: Implications for the study of cell lifespan. MICROBIAL CELL 2019; 6:397-413. [PMID: 31528631 PMCID: PMC6717879 DOI: 10.15698/mic2019.09.690] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Baker's yeast has a finite lifespan and ages in two ways: a mother cell can only divide so many times (its replicative lifespan), and a non-dividing cell can only live so long (its chronological lifespan). Wild and laboratory yeast strains exhibit natural variation for each type of lifespan, and the genetic basis for this variation has been generalized to other eukaryotes, including metazoans. To date, yeast chronological lifespan has chiefly been studied in relation to the rate and mode of functional decline among non-dividing cells in nutrient-depleted batch culture. However, this culture method does not accurately capture two major classes of long-lived metazoan cells: cells that are terminally differentiated and metabolically active for periods that approximate animal lifespan (e.g. cardiac myocytes), and cells that are pluripotent and metabolically quiescent (e.g. stem cells). Here, we consider alternative ways of cultivating Saccharomyces cerevisiae so that these different metabolic states can be explored in non-dividing cells: (i) yeast cultured as giant colonies on semi-solid agar, (ii) yeast cultured in retentostats and provided sufficient nutrients to meet minimal energy requirements, and (iii) yeast encapsulated in a semisolid matrix and fed ad libitum in bioreactors. We review the physiology of yeast cultured under each of these conditions, and explore their potential to provide unique insights into determinants of chronological lifespan in the cells of higher eukaryotes.
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Affiliation(s)
- Jordan Gulli
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332
| | - Emily Cook
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332
| | - Eugene Kroll
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332
| | - Adam Rosebrock
- Donnelly Centre for Cellular and Biological Research and Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.,Present address: Stony Brook School of Medicine, Stony Brook University, Stony Brook, NY 11794
| | - Amy Caudy
- Donnelly Centre for Cellular and Biological Research and Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Frank Rosenzweig
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332
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16
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Tate JJ, Tolley EA, Cooper TG. Sit4 and PP2A Dephosphorylate Nitrogen Catabolite Repression-Sensitive Gln3 When TorC1 Is Up- as Well as Downregulated. Genetics 2019; 212:1205-1225. [PMID: 31213504 PMCID: PMC6707456 DOI: 10.1534/genetics.119.302371] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 06/17/2019] [Indexed: 11/18/2022] Open
Abstract
Saccharomyces cerevisiae lives in boom and bust nutritional environments. Sophisticated regulatory systems have evolved to rapidly cope with these changes while preserving intracellular homeostasis. Target of Rapamycin Complex 1 (TorC1), is a serine/threonine kinase complex and a principle nitrogen-responsive regulator. TorC1 is activated by excess nitrogen and downregulated by limiting nitrogen. Two of TorC1's many downstream targets are Gln3 and Gat1-GATA-family transcription activators-whose localization and function are Nitrogen Catabolite Repression- (NCR-) sensitive. In nitrogen replete environments, TorC1 is activated, thereby inhibiting the PTap42-Sit4 and PTap42-PP2A (Pph21/Pph22-Tpd3, Pph21,22-Rts1/Cdc55) phosphatase complexes. Gln3 is phosphorylated, sequestered in the cytoplasm and NCR-sensitive transcription repressed. In nitrogen-limiting conditions, TorC1 is downregulated and PTap42-Sit4 and PTap42-PP2A are active. They dephosphorylate Gln3, which dissociates from Ure2, relocates to the nucleus, and activates transcription. A paradoxical observation, however, led us to suspect that Gln3 control was more complex than appreciated, i.e., Sit4 dephosphorylates Gln3 more in excess than in limiting nitrogen conditions. This paradox motivated us to reinvestigate the roles of these phosphatases in Gln3 regulation. We discovered that: (i) Sit4 and PP2A actively function both in conditions where TorC1 is activated as well as down-regulated; (ii) nuclear Gln3 is more highly phosphorylated than when it is sequestered in the cytoplasm; (iii) in nitrogen-replete conditions, Gln3 relocates from the nucleus to the cytoplasm, where it is dephosphorylated by Sit4 and PP2A; and (iv) in nitrogen excess and limiting conditions, Sit4, PP2A, and Ure2 are all required to maintain cytoplasmic Gln3 in its dephosphorylated form.
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Affiliation(s)
- Jennifer J Tate
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, 38163 Tennessee
| | - Elizabeth A Tolley
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, 38163 Tennessee
| | - Terrance G Cooper
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, 38163 Tennessee
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17
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So YS, Lee DG, Idnurm A, Ianiri G, Bahn YS. The TOR Pathway Plays Pleiotropic Roles in Growth and Stress Responses of the Fungal Pathogen Cryptococcus neoformans. Genetics 2019; 212:1241-1258. [PMID: 31175227 PMCID: PMC6707454 DOI: 10.1534/genetics.119.302191] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 06/02/2019] [Indexed: 11/18/2022] Open
Abstract
The target of rapamycin (TOR) pathway is an evolutionarily conserved signal transduction system that governs a plethora of eukaryotic biological processes, but its role in Cryptococcus neoformans remains elusive. In this study, we investigated the TOR pathway by functionally characterizing two Tor-like kinases, Tor1 and Tlk1, in C. neoformans We successfully deleted TLK1, but not TOR1TLK1 deletion did not result in any evident in vitro phenotypes, suggesting that Tlk1 is dispensable for the growth of C. neoformans We demonstrated that Tor1, but not Tlk1, is essential and the target of rapamycin by constructing and analyzing conditionally regulated strains and sporulation analysis of heterozygous mutants in the diploid strain background. To further analyze the Tor1 function, we constructed constitutive TOR1 overexpression strains. Tor1 negatively regulated thermotolerance and the DNA damage response, which are two important virulence factors of C. neoformansTOR1 overexpression reduced Mpk1 phosphorylation, which is required for cell wall integrity and thermoresistance, and Rad53 phosphorylation, which governs the DNA damage response pathway. Tor1 is localized to the cytoplasm, but enriched in the vacuole membrane. Phosphoproteomics and transcriptomics revealed that Tor1 regulates a variety of biological processes, including metabolic processes, cytoskeleton organization, ribosome biogenesis, and stress response. TOR inhibition by rapamycin caused actin depolarization in a Tor1-dependent manner. Finally, screening rapamycin-sensitive and -resistant kinase and transcription factor mutants revealed that the TOR pathway may crosstalk with a number of stress signaling pathways. In conclusion, our study demonstrates that a single Tor1 kinase plays pleiotropic roles in C. neoformans.
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Affiliation(s)
- Yee-Seul So
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Dong-Gi Lee
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Alexander Idnurm
- School of BioSciences, The University of Melbourne, Victoria 3010, Australia
| | - Giuseppe Ianiri
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710
| | - Yong-Sun Bahn
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
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18
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Abstract
The AGC signaling pathway represents a conserved distinct signaling pathway in regulation of fungal differentiation and virulence, while it has not been identified or characterized in the sugarcane smut fungus Sporisorium scitamineum. In this study, we identified a PAS domain-containing AGC kinase, SsAgc1, in S. scitamineum. Functional analysis revealed that SsAgc1 plays a regulatory role on the fungal dimorphic switch. Sporisorium scitamineum is the fungal pathogen causing severe sugarcane smut disease that leads to massive economic losses globally. S. scitamineum invades host cane by dikaryotic hyphae, formed after sexual mating of two haploid sporidia of opposite mating type. Therefore, mating/filamentation is critical for S. scitamineum pathogenicity, while its molecular mechanisms remain largely unknown. The AGC (cyclic AMP [cAMP]-dependent protein kinase 1 [protein kinase A {PKA}], cGMP-dependent protein kinase [PKG], and protein kinase C [PKC]) kinase family is a group of serine/threonine (Ser/Thr) protein kinases conserved among eukaryotic genomes, serving a variety of physiological functions, including cell growth, metabolism, differentiation, and cell death. In this study, we identified an AGC kinase, named SsAgc1 (for S. scitamineum Agc1), and characterized its function by reverse genetics. Our results showed that SsAgc1 is critical for S. scitamineum mating/filamentation and pathogenicity, and oxidative stress tolerance under some circumstances. Transcriptional profiling revealed that the SsAgc1 signaling pathway may control expression of the genes governing fungal mating/filamentation and tryptophan metabolism, especially for tryptophol production. We showed that tryptophan and tryptophol could at least partially restore ssagc1Δ mating/filamentation. Overall, our work revealed a signaling pathway mediated by AGC protein kinases to regulate fungal mating/filamentation, possibly through sensing and responding to tryptophol as signal molecules. IMPORTANCE The AGC signaling pathway represents a conserved distinct signaling pathway in regulation of fungal differentiation and virulence, while it has not been identified or characterized in the sugarcane smut fungus Sporisorium scitamineum. In this study, we identified a PAS domain-containing AGC kinase, SsAgc1, in S. scitamineum. Functional analysis revealed that SsAgc1 plays a regulatory role on the fungal dimorphic switch.
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19
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Guaragnella N, Coyne LP, Chen XJ, Giannattasio S. Mitochondria-cytosol-nucleus crosstalk: learning from Saccharomyces cerevisiae. FEMS Yeast Res 2019; 18:5066171. [PMID: 30165482 DOI: 10.1093/femsyr/foy088] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 08/02/2018] [Indexed: 12/16/2022] Open
Abstract
Mitochondria are key cell organelles with a prominent role in both energetic metabolism and the maintenance of cellular homeostasis. Since mitochondria harbor their own genome, which encodes a limited number of proteins critical for oxidative phosphorylation and protein translation, their function and biogenesis strictly depend upon nuclear control. The yeast Saccharomyces cerevisiae has been a unique model for understanding mitochondrial DNA organization and inheritance as well as for deciphering the process of assembly of mitochondrial components. In the last three decades, yeast also provided a powerful tool for unveiling the communication network that coordinates the functions of the nucleus, the cytosol and mitochondria. This crosstalk regulates how cells respond to extra- and intracellular changes either to maintain cellular homeostasis or to activate cell death. This review is focused on the key pathways that mediate nucleus-cytosol-mitochondria communications through both transcriptional regulation and proteostatic signaling. We aim to highlight yeast that likely continues to serve as a productive model organism for mitochondrial research in the years to come.
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Affiliation(s)
- Nicoletta Guaragnella
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies, CNR, Via Amendola 165/A, 70126 Bari, Italy
| | - Liam P Coyne
- Department of Biochemistry and Molecular Biology, State University of New York Upstate Medical University, 750 East Adams Street, Syracuse, NY 13210, USA
| | - Xin Jie Chen
- Department of Biochemistry and Molecular Biology, State University of New York Upstate Medical University, 750 East Adams Street, Syracuse, NY 13210, USA
| | - Sergio Giannattasio
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies, CNR, Via Amendola 165/A, 70126 Bari, Italy
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20
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Dakik P, Medkour Y, Mohammad K, Titorenko VI. Mechanisms Through Which Some Mitochondria-Generated Metabolites Act as Second Messengers That Are Essential Contributors to the Aging Process in Eukaryotes Across Phyla. Front Physiol 2019; 10:461. [PMID: 31057428 PMCID: PMC6482166 DOI: 10.3389/fphys.2019.00461] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 04/02/2019] [Indexed: 12/21/2022] Open
Abstract
Recent studies have revealed that some low-molecular weight molecules produced in mitochondria are essential contributing factors to aging and aging-associated pathologies in evolutionarily distant eukaryotes. These molecules are intermediates or products of certain metabolic reactions that are activated in mitochondria in response to specific changes in the nutrient, stress, proliferation, or age status of the cell. After being released from mitochondria, these metabolites directly or indirectly change activities of a distinct set of protein sensors that reside in various cellular locations outside of mitochondria. Because these protein sensors control the efficiencies of some pro- or anti-aging cellular processes, such changes in their activities allow to create a pro- or anti-aging cellular pattern. Thus, mitochondria can function as signaling platforms that respond to certain changes in cell stress and physiology by remodeling their metabolism and releasing a specific set of metabolites known as "mitobolites." These mitobolites then define the pace of cellular and organismal aging because they regulate some longevity-defining processes taking place outside of mitochondria. In this review, we discuss recent progress in understanding mechanisms underlying the ability of mitochondria to function as such signaling platforms in aging and aging-associated diseases.
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21
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Deprez MA, Eskes E, Winderickx J, Wilms T. The TORC1-Sch9 pathway as a crucial mediator of chronological lifespan in the yeast Saccharomyces cerevisiae. FEMS Yeast Res 2019; 18:4980911. [PMID: 29788208 DOI: 10.1093/femsyr/foy048] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 04/19/2018] [Indexed: 12/18/2022] Open
Abstract
The concept of ageing is one that has intrigued mankind since the beginning of time and is now more important than ever as the incidence of age-related disorders is increasing in our ageing population. Over the past decades, extensive research has been performed using various model organisms. As such, it has become apparent that many fundamental aspects of biological ageing are highly conserved across large evolutionary distances. In this review, we illustrate that the unicellular eukaryotic organism Saccharomyces cerevisiae has proven to be a valuable tool to gain fundamental insights into the molecular mechanisms of cellular ageing in multicellular eukaryotes. In addition, we outline the current knowledge on how downregulation of nutrient signaling through the target of rapamycin (TOR)-Sch9 pathway or reducing calorie intake attenuates many detrimental effects associated with ageing and leads to the extension of yeast chronological lifespan. Given that both TOR Complex 1 (TORC1) and Sch9 have mammalian orthologues that have been implicated in various age-related disorders, unraveling the connections of TORC1 and Sch9 with yeast ageing may provide additional clues on how their mammalian orthologues contribute to the mechanisms underpinning human ageing and health.
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Affiliation(s)
- Marie-Anne Deprez
- Department of Biology, Functional Biology, KU Leuven, Kasteelpark Arenberg 31, 3001 Heverlee, Belgium
| | - Elja Eskes
- Department of Biology, Functional Biology, KU Leuven, Kasteelpark Arenberg 31, 3001 Heverlee, Belgium
| | - Joris Winderickx
- Department of Biology, Functional Biology, KU Leuven, Kasteelpark Arenberg 31, 3001 Heverlee, Belgium
| | - Tobias Wilms
- Department of Biology, Functional Biology, KU Leuven, Kasteelpark Arenberg 31, 3001 Heverlee, Belgium
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22
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Dakik P, McAuley M, Chancharoen M, Mitrofanova D, Lozano Rodriguez ME, Baratang Junio JA, Lutchman V, Cortes B, Simard É, Titorenko VI. Pairwise combinations of chemical compounds that delay yeast chronological aging through different signaling pathways display synergistic effects on the extent of aging delay. Oncotarget 2019; 10:313-338. [PMID: 30719227 PMCID: PMC6349451 DOI: 10.18632/oncotarget.26553] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 12/20/2018] [Indexed: 01/08/2023] Open
Abstract
We have recently discovered six plant extracts that delay yeast chronological aging. Most of them affect different nodes, edges and modules of an evolutionarily conserved network of longevity regulation that integrates certain signaling pathways and protein kinases; this network is also under control of such aging-delaying chemical compounds as spermidine and resveratrol. We have previously shown that, if a strain carrying an aging-delaying single-gene mutation affecting a certain node, edge or module of the network is exposed to some of the six plant extracts, the mutation and the plant extract enhance aging-delaying efficiencies of each other so that their combination has a synergistic effect on the extent of aging delay. We therefore hypothesized that a pairwise combination of two aging-delaying plant extracts or a combination of one of these plant extracts and spermidine or resveratrol may have a synergistic effect on the extent of aging delay only if each component of this combination targets a different element of the network. To test our hypothesis, we assessed longevity-extending efficiencies of all possible pairwise combinations of the six plant extracts or of one of them and spermidine or resveratrol in chronologically aging yeast. In support of our hypothesis, we show that only pairwise combinations of naturally-occurring chemical compounds that slow aging through different nodes, edges and modules of the network delay aging in a synergistic manner.
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Affiliation(s)
- Pamela Dakik
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Mélissa McAuley
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | | | - Darya Mitrofanova
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | | | | | - Vicky Lutchman
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Berly Cortes
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Éric Simard
- Idunn Technologies Inc., Rosemere, Quebec, Canada
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23
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Orlandi I, Stamerra G, Vai M. Altered Expression of Mitochondrial NAD + Carriers Influences Yeast Chronological Lifespan by Modulating Cytosolic and Mitochondrial Metabolism. Front Genet 2018; 9:676. [PMID: 30619489 PMCID: PMC6305841 DOI: 10.3389/fgene.2018.00676] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 12/04/2018] [Indexed: 01/07/2023] Open
Abstract
Nicotinamide adenine dinucleotide (NAD+) represents an essential cofactor in sustaining cellular bioenergetics and maintaining cellular fitness, and has emerged as a therapeutic target to counteract aging and age-related diseases. Besides NAD+ involvement in multiple redox reactions, it is also required as co-substrate for the activity of Sirtuins, a family of evolutionary conserved NAD+-dependent deacetylases that regulate both metabolism and aging. The founding member of this family is Sir2 of Saccharomyces cerevisiae, a well-established model system for studying aging of post-mitotic mammalian cells. In this context, it refers to chronological aging, in which the chronological lifespan (CLS) is measured. In this paper, we investigated the effects of changes in the cellular content of NAD+ on CLS by altering the expression of mitochondrial NAD+ carriers, namely Ndt1 and Ndt2. We found that the deletion or overexpression of these carriers alters the intracellular levels of NAD+ with opposite outcomes on CLS. In particular, lack of both carriers decreases NAD+ content and extends CLS, whereas NDT1 overexpression increases NAD+ content and reduces CLS. This correlates with opposite cytosolic and mitochondrial metabolic assets shown by the two types of mutants. In the former, an increase in the efficiency of oxidative phosphorylation is observed together with an enhancement of a pro-longevity anabolic metabolism toward gluconeogenesis and trehalose storage. On the contrary, NDT1 overexpression brings about on the one hand, a decrease in the respiratory efficiency generating harmful superoxide anions, and on the other, a decrease in gluconeogenesis and trehalose stores: all this is reflected into a time-dependent loss of mitochondrial functionality during chronological aging.
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Affiliation(s)
- Ivan Orlandi
- SYSBIO Centre for Systems Biology, Milan, Italy.,Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
| | - Giulia Stamerra
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
| | - Marina Vai
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
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24
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Sun G, Elowsky C, Li G, Wilson RA. TOR-autophagy branch signaling via Imp1 dictates plant-microbe biotrophic interface longevity. PLoS Genet 2018; 14:e1007814. [PMID: 30462633 PMCID: PMC6281275 DOI: 10.1371/journal.pgen.1007814] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 12/05/2018] [Accepted: 11/06/2018] [Indexed: 01/07/2023] Open
Abstract
Like other intracellular eukaryotic phytopathogens, the devastating rice blast fungus Magnaporthe (Pyricularia) oryzae first infects living host cells by elaborating invasive hyphae (IH) surrounded by a plant-derived membrane. This forms an extended biotrophic interface enclosing an apoplastic compartment into which fungal effectors can be deployed to evade host detection. M. oryzae also forms a focal, plant membrane-rich structure, the biotrophic interfacial complex (BIC), that accumulates cytoplasmic effectors for translocation into host cells. Molecular decision-making processes integrating fungal growth and metabolism in host cells with interface function and dynamics are unknown. Here, we report unanticipated roles for the M. oryzae Target-of-Rapamycin (TOR) nutrient-signaling pathway in mediating plant-fungal biotrophic interface membrane integrity. Through a forward genetics screen for M. oryzae mutant strains resistant to the specific TOR kinase inhibitor rapamycin, we discovered IMP1 encoding a novel vacuolar protein required for membrane trafficking, V-ATPase assembly, organelle acidification and autophagy induction. During infection, Δimp1 deletants developed intracellular IH in the first infected rice cell following cuticle penetration. However, fluorescently labeled effector probes revealed that interface membrane integrity became compromised as biotrophy progressed, abolishing the BIC and releasing apoplastic effectors into host cytoplasm. Growth between rice cells was restricted. TOR-independent autophagy activation in Δimp1 deletants (following infection) remediated interface function and cell-to-cell growth. Autophagy inhibition in wild type (following infection) recapitulated Δimp1. In addition to vacuoles, Imp1GFP localized to IH membranes in an autophagy-dependent manner. Collectively, our results suggest TOR-Imp1-autophagy branch signaling mediates membrane homeostasis to prevent catastrophic erosion of the biotrophic interface, thus facilitating fungal growth in living rice cells. The significance of this work lays in elaborating a novel molecular mechanism of infection stressing the dominance of fungal metabolism and metabolic control in sustaining long-term plant-microbe interactions. This work also has implications for understanding the enigmatic biotrophy to necrotrophy transition. Plant-associated fungi can form intimate connections with living host cells. Clarifying the molecular drivers of these interactions, and which partner is dominant, might be important in understanding how beneficial plant-fungal relationships can be enhanced to improve crop yields while pathogenic interactions that threaten crop health are disrupted. In common with other symbionts and phytopathogens, the devastating rice blast fungus Magnaporthe oryzae elaborates invasive hyphae in living host cells surrounded by plant-derived membranes. Nothing is known at the molecular signaling level about how such plant-microbe biotrophic interfacial zones are maintained as the fungus grows in and between host cells. Here, we report that fungal membrane trafficking processes controlled by nutrient signaling pathways are critical for maintaining biotrophic interface integrity during M. oryzae growth in rice cells. Impairing these processes resulted in erosion of the plant-microbe interface and failure of the fungus to thrive. To our knowledge, this work presents the first evidence indicating that the fungal partner is dominant in propagating the plant-microbe boundary. This suggests that the biotrophic interface is a fungal construct and provides clues on how such interfaces might be modulated to benefit the host plant.
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Affiliation(s)
- Guangchao Sun
- Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
| | - Christian Elowsky
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
| | - Gang Li
- Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
| | - Richard A. Wilson
- Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
- * E-mail:
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25
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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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Mohammad K, Dakik P, Medkour Y, McAuley M, Mitrofanova D, Titorenko VI. Some Metabolites Act as Second Messengers in Yeast Chronological Aging. Int J Mol Sci 2018; 19:ijms19030860. [PMID: 29543708 PMCID: PMC5877721 DOI: 10.3390/ijms19030860] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 03/12/2018] [Accepted: 03/13/2018] [Indexed: 02/06/2023] Open
Abstract
The concentrations of some key metabolic intermediates play essential roles in regulating the longevity of the chronologically aging yeast Saccharomyces cerevisiae. These key metabolites are detected by certain ligand-specific protein sensors that respond to concentration changes of the key metabolites by altering the efficiencies of longevity-defining cellular processes. The concentrations of the key metabolites that affect yeast chronological aging are controlled spatially and temporally. Here, we analyze mechanisms through which the spatiotemporal dynamics of changes in the concentrations of the key metabolites influence yeast chronological lifespan. Our analysis indicates that a distinct set of metabolites can act as second messengers that define the pace of yeast chronological aging. Molecules that can operate both as intermediates of yeast metabolism and as second messengers of yeast chronological aging include reduced nicotinamide adenine dinucleotide phosphate (NADPH), glycerol, trehalose, hydrogen peroxide, amino acids, sphingolipids, spermidine, hydrogen sulfide, acetic acid, ethanol, free fatty acids, and diacylglycerol. We discuss several properties that these second messengers of yeast chronological aging have in common with second messengers of signal transduction. We outline how these second messengers of yeast chronological aging elicit changes in cell functionality and viability in response to changes in the nutrient, energy, stress, and proliferation status of the cell.
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Affiliation(s)
- Karamat Mohammad
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
| | - Paméla Dakik
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
| | - Younes Medkour
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
| | - Mélissa McAuley
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
| | - Darya Mitrofanova
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
| | - Vladimir I Titorenko
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
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Leonov A, Arlia-Ciommo A, Bourque SD, Koupaki O, Kyryakov P, Dakik P, McAuley M, Medkour Y, Mohammad K, Di Maulo T, Titorenko VI. Specific changes in mitochondrial lipidome alter mitochondrial proteome and increase the geroprotective efficiency of lithocholic acid in chronologically aging yeast. Oncotarget 2018; 8:30672-30691. [PMID: 28410198 PMCID: PMC5458158 DOI: 10.18632/oncotarget.16766] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 03/20/2017] [Indexed: 02/07/2023] Open
Abstract
We have previously found that exogenously added lithocholic acid delays yeast chronological aging. We demonstrated that lithocholic acid enters the yeast cell, is sorted to mitochondria, resides in both mitochondrial membranes, changes the relative concentrations of different membrane phospholipids, triggers changes in the concentrations of many mitochondrial proteins, and alters some key aspects of mitochondrial functionality. We hypothesized that the lithocholic acid-driven changes in mitochondrial lipidome may have a causal role in the remodeling of mitochondrial proteome, which may in turn alter the functional state of mitochondria to create a mitochondrial pattern that delays yeast chronological aging. Here, we test this hypothesis by investigating how the ups1?, ups2? and psd1? mutations that eliminate enzymes involved in mitochondrial phospholipid metabolism influence the mitochondrial lipidome. We also assessed how these mutations affect the mitochondrial proteome, influence mitochondrial functionality and impinge on the efficiency of aging delay by lithocholic acid. Our findings provide evidence that 1) lithocholic acid initially creates a distinct pro-longevity pattern of mitochondrial lipidome by proportionally decreasing phosphatidylethanolamine and cardiolipin concentrations to maintain equimolar concentrations of these phospholipids, and by increasing phosphatidic acid concentration; 2) this pattern of mitochondrial lipidome allows to establish a specific, aging-delaying pattern of mitochondrial proteome; and 3) this pattern of mitochondrial proteome plays an essential role in creating a distinctive, geroprotective pattern of mitochondrial functionality.
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Affiliation(s)
- Anna Leonov
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | | | - Simon D Bourque
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Olivia Koupaki
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Pavlo Kyryakov
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Paméla Dakik
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Mélissa McAuley
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Younes Medkour
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Karamat Mohammad
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Tamara Di Maulo
- Department of Biology, Concordia University, Montreal, Quebec, Canada
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Lutchman V, Dakik P, McAuley M, Cortes B, Ferraye G, Gontmacher L, Graziano D, Moukhariq FZ, Simard É, Titorenko VI. Six plant extracts delay yeast chronological aging through different signaling pathways. Oncotarget 2018; 7:50845-50863. [PMID: 27447556 PMCID: PMC5239441 DOI: 10.18632/oncotarget.10689] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 07/07/2016] [Indexed: 01/19/2023] Open
Abstract
Our recent study has revealed six plant extracts that slow yeast chronological aging more efficiently than any chemical compound yet described. The rate of aging in yeast is controlled by an evolutionarily conserved network of integrated signaling pathways and protein kinases. Here, we assessed how single-gene-deletion mutations eliminating each of these pathways and kinases affect the aging-delaying efficiencies of the six plant extracts. Our findings imply that these extracts slow aging in the following ways: 1) plant extract 4 decreases the efficiency with which the pro-aging TORC1 pathway inhibits the anti-aging SNF1 pathway; 2) plant extract 5 mitigates two different branches of the pro-aging PKA pathway; 3) plant extract 6 coordinates processes that are not assimilated into the network of presently known signaling pathways/protein kinases; 4) plant extract 8 diminishes the inhibitory action of PKA on SNF1; 5) plant extract 12 intensifies the anti-aging protein kinase Rim15; and 6) plant extract 21 inhibits a form of the pro-aging protein kinase Sch9 that is activated by the pro-aging PKH1/2 pathway.
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Affiliation(s)
- Vicky Lutchman
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Pamela Dakik
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Mélissa McAuley
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Berly Cortes
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - George Ferraye
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Leonid Gontmacher
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - David Graziano
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | | | - Éric Simard
- Idunn Technologies Inc., Rosemere, Quebec, Canada
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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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30
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Engel SR, Skrzypek MS, Hellerstedt ST, Wong ED, Nash RS, Weng S, Binkley G, Sheppard TK, Karra K, Cherry JM. Updated regulation curation model at the Saccharomyces Genome Database. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2018; 2018:4913686. [PMID: 29688362 PMCID: PMC5829562 DOI: 10.1093/database/bay007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/08/2018] [Indexed: 11/29/2022]
Abstract
The Saccharomyces Genome Database (SGD) provides comprehensive, integrated biological information for the budding yeast Saccharomyces cerevisiae, along with search and analysis tools to explore these data, enabling the discovery of functional relationships between sequence and gene products in fungi and higher organisms. We have recently expanded our data model for regulation curation to address regulation at the protein level in addition to transcription, and are presenting the expanded data on the ‘Regulation’ pages at SGD. These pages include a summary describing the context under which the regulator acts, manually curated and high-throughput annotations showing the regulatory relationships for that gene and a graphical visualization of its regulatory network and connected networks. For genes whose products regulate other genes or proteins, the Regulation page includes Gene Ontology enrichment analysis of the biological processes in which those targets participate. For DNA-binding transcription factors, we also provide other information relevant to their regulatory function, such as DNA binding site motifs and protein domains. As with other data types at SGD, all regulatory relationships and accompanying data are available through YeastMine, SGD’s data warehouse based on InterMine. Database URL: http://www.yeastgenome.org
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Affiliation(s)
- Stacia R Engel
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Marek S Skrzypek
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | | | - Edith D Wong
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Robert S Nash
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Shuai Weng
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Gail Binkley
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Travis K Sheppard
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Kalpana Karra
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - J Michael Cherry
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
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31
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More than One Way in: Three Gln3 Sequences Required To Relieve Negative Ure2 Regulation and Support Nuclear Gln3 Import in Saccharomyces cerevisiae. Genetics 2017; 208:207-227. [PMID: 29113979 DOI: 10.1534/genetics.117.300457] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 11/02/2017] [Indexed: 01/20/2023] Open
Abstract
Gln3 is responsible for Nitrogen Catabolite Repression-sensitive transcriptional activation in the yeast Saccharomyces cerevisiae In nitrogen-replete medium, Gln3 is cytoplasmic and NCR-sensitive transcription is repressed. In nitrogen-limiting medium, in cells treated with TorC1 inhibitor, rapamycin, or the glutamine synthetase inhibitor, methionine sulfoximine (Msx), Gln3 becomes highly nuclear and NCR-sensitive transcription derepressed. Previously, nuclear Gln3 localization was concluded to be mediated by a single nuclear localization sequence, NLS1. Here, we show that nuclear Gln3-Myc13 localization is significantly more complex than previously appreciated. We identify three Gln3 sequences, other than NLS1, that are highly required for nuclear Gln3-Myc13 localization. Two of these sequences exhibit characteristics of monopartite (K/R-Rich NLS) and bipartite (S/R NLS) NLSs, respectively. Mutations altering these sequences are partially epistatic to a ure2Δ. The third sequence, the Ure2 relief sequence, exhibits no predicted NLS homology and is only necessary when Ure2 is present. Substitution of the basic amino acid repeats in the Ure2 relief sequence or phosphomimetic aspartate substitutions for the serine residues between them abolishes nuclear Gln3-Myc13 localization in response to both limiting nitrogen and rapamycin treatment. In contrast, Gln3-Myc13 responses are normal in parallel serine-to-alanine substitution mutants. These observations suggest that Gln3 responses to specific nitrogen environments likely occur in multiple steps that can be genetically separated. At least one general step that is associated with the Ure2 relief sequence may be prerequisite for responses to the specific stimuli of growth in poor nitrogen sources and rapamycin inhibition of TorC1.
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32
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Heinisch JJ, Rodicio R. Protein kinase C in fungi—more than just cell wall integrity. FEMS Microbiol Rev 2017; 42:4562651. [DOI: 10.1093/femsre/fux051] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 10/19/2017] [Indexed: 11/13/2022] Open
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33
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Leonov A, Feldman R, Piano A, Arlia-Ciommo A, Lutchman V, Ahmadi M, Elsaser S, Fakim H, Heshmati-Moghaddam M, Hussain A, Orfali S, Rajen H, Roofigari-Esfahani N, Rosanelli L, Titorenko VI. Caloric restriction extends yeast chronological lifespan via a mechanism linking cellular aging to cell cycle regulation, maintenance of a quiescent state, entry into a non-quiescent state and survival in the non-quiescent state. Oncotarget 2017; 8:69328-69350. [PMID: 29050207 PMCID: PMC5642482 DOI: 10.18632/oncotarget.20614] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 08/14/2017] [Indexed: 12/22/2022] Open
Abstract
A yeast culture grown in a nutrient-rich medium initially containing 2% glucose is not limited in calorie supply. When yeast cells cultured in this medium consume glucose, they undergo cell cycle arrest at a checkpoint in late G1 and differentiate into quiescent and non-quiescent cell populations. Studies of such differentiation have provided insights into mechanisms of yeast chronological aging under conditions of excessive calorie intake. Caloric restriction is an aging-delaying dietary intervention. Here, we assessed how caloric restriction influences the differentiation of chronologically aging yeast cultures into quiescent and non-quiescent cells, and how it affects their properties. We found that caloric restriction extends yeast chronological lifespan via a mechanism linking cellular aging to cell cycle regulation, maintenance of quiescence, entry into a non-quiescent state and survival in this state. Our findings suggest that caloric restriction delays yeast chronological aging by causing specific changes in the following: 1) a checkpoint in G1 for cell cycle arrest and entry into a quiescent state; 2) a growth phase in which high-density quiescent cells are committed to become low-density quiescent cells; 3) the differentiation of low-density quiescent cells into low-density non-quiescent cells; and 4) the conversion of high-density quiescent cells into high-density non-quiescent cells.
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Affiliation(s)
- Anna Leonov
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Rachel Feldman
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Amanda Piano
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | | | - Vicky Lutchman
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Masoumeh Ahmadi
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Sarah Elsaser
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Hana Fakim
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | | | - Asimah Hussain
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Sandra Orfali
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | | | | | - Leana Rosanelli
- Department of Biology, Concordia University, Montreal, Quebec, Canada
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Eskes E, Deprez MA, Wilms T, Winderickx J. pH homeostasis in yeast; the phosphate perspective. Curr Genet 2017; 64:155-161. [PMID: 28856407 PMCID: PMC5778149 DOI: 10.1007/s00294-017-0743-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 08/21/2017] [Accepted: 08/22/2017] [Indexed: 12/22/2022]
Abstract
Recent research further clarified the molecular mechanisms that link nutrient signaling and pH homeostasis with the regulation of growth and survival of the budding yeast Saccharomyces cerevisiae. The central nutrient signaling kinases PKA, TORC1, and Sch9 are intimately associated to pH homeostasis, presumably allowing them to concert far-reaching phenotypical repercussions of nutritional cues. To exemplify such repercussions, we briefly describe consequences for phosphate uptake and signaling and outline interactions between phosphate homeostasis and the players involved in intra- and extracellular pH control. Inorganic phosphate uptake, its subcellular distribution, and its conversion into polyphosphates are dependent on the proton gradients created over different membranes. Conversely, polyphosphate metabolism appears to contribute in determining the intracellular pH. Additionally, inositol pyrophosphates are emerging as potent determinants of growth potential, in this way providing feedback from phosphate metabolism onto the central nutrient signaling kinases. All these data point towards the importance of phosphate metabolism in the reciprocal regulation of nutrient signaling and pH homeostasis.
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Affiliation(s)
- Elja Eskes
- Functional Biology, KU Leuven, Kasteelpark Arenberg 31 box 2433, 3001, Heverlee, Belgium
| | - Marie-Anne Deprez
- Functional Biology, KU Leuven, Kasteelpark Arenberg 31 box 2433, 3001, Heverlee, Belgium
| | - Tobias Wilms
- Functional Biology, KU Leuven, Kasteelpark Arenberg 31 box 2433, 3001, Heverlee, Belgium
| | - Joris Winderickx
- Functional Biology, KU Leuven, Kasteelpark Arenberg 31 box 2433, 3001, Heverlee, Belgium.
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Pérez-Hidalgo L, Moreno S. Coupling TOR to the Cell Cycle by the Greatwall-Endosulfine-PP2A-B55 Pathway. Biomolecules 2017; 7:biom7030059. [PMID: 28777780 PMCID: PMC5618240 DOI: 10.3390/biom7030059] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 07/31/2017] [Accepted: 08/02/2017] [Indexed: 01/14/2023] Open
Abstract
Cell growth and division are two processes tightly coupled in proliferating cells. While Target of Rapamycin (TOR) is the master regulator of growth, the cell cycle is dictated by the activity of the cyclin-dependent kinases (CDKs). A long-standing question in cell biology is how these processes may be connected. Recent work has highlighted that regulating the phosphatases that revert CDK phosphorylations is as important as regulating the CDKs for cell cycle progression. At mitosis, maintaining a low level of protein phosphatase 2A (PP2A)-B55 activity is essential for CDK substrates to achieve the correct level of phosphorylation. The conserved Greatwall–Endosulfine pathway has been shown to be required for PP2A-B55 inhibition at mitosis in yeasts and multicellular organisms. Interestingly, in yeasts, the Greatwall–Endosulfine pathway is negatively regulated by TOR Complex 1 (TORC1). Moreover, Greatwall–Endosulfine activation upon TORC1 inhibition has been shown to regulate the progression of the cell cycle at different points: the G1 phase in budding yeast, the G2/M transition and the differentiation response in fission yeast, and the entry into quiescence in both budding and fission yeasts. In this review, we discuss the recent findings on how the Greatwall–Endosulfine pathway may provide a connection between cell growth and the cell cycle machinery.
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Affiliation(s)
- Livia Pérez-Hidalgo
- Institute of Functional Biology and Genomics (IBFG), CSIC/University of Salamanca, 37007 Salamanca, Spain.
- Institute of Biomedical Research of Salamanca (IBSAL), University Hospital of Salamanca, 37007 Salamanca, Spain.
| | - Sergio Moreno
- Institute of Functional Biology and Genomics (IBFG), CSIC/University of Salamanca, 37007 Salamanca, Spain.
- Institute of Biomedical Research of Salamanca (IBSAL), University Hospital of Salamanca, 37007 Salamanca, Spain.
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36
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Differential control of ageing and lifespan by isoforms and splice variants across the mTOR network. Essays Biochem 2017; 61:349-368. [PMID: 28698309 DOI: 10.1042/ebc20160086] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 05/19/2017] [Accepted: 05/23/2017] [Indexed: 11/17/2022]
Abstract
Ageing can be defined as the gradual deterioration of physiological functions, increasing the incidence of age-related disorders and the probability of death. Therefore, the term ageing not only reflects the lifespan of an organism but also refers to progressive functional impairment and disease. The nutrient-sensing kinase mTOR (mammalian target of rapamycin) is a major determinant of ageing. mTOR promotes cell growth and controls central metabolic pathways including protein biosynthesis, autophagy and glucose and lipid homoeostasis. The concept that mTOR has a crucial role in ageing is supported by numerous reports on the lifespan-prolonging effects of the mTOR inhibitor rapamycin in invertebrate and vertebrate model organisms. Dietary restriction increases lifespan and delays ageing phenotypes as well and mTOR has been assigned a major role in this process. This may suggest a causal relationship between the lifespan of an organism and its metabolic phenotype. More than 25 years after mTOR's discovery, a wealth of metabolic and ageing-related effects have been reported. In this review, we cover the current view on the contribution of the different elements of the mTOR signalling network to lifespan and age-related metabolic impairment. We specifically focus on distinct roles of isoforms and splice variants across the mTOR network. The comprehensive analysis of mouse knockout studies targeting these variants does not support a tight correlation between lifespan prolongation and improved metabolic phenotypes and questions the strict causal relationship between them.
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37
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The yeast protein kinase Sch9 adjusts V-ATPase assembly/disassembly to control pH homeostasis and longevity in response to glucose availability. PLoS Genet 2017; 13:e1006835. [PMID: 28604780 PMCID: PMC5484544 DOI: 10.1371/journal.pgen.1006835] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Revised: 06/26/2017] [Accepted: 05/23/2017] [Indexed: 11/19/2022] Open
Abstract
The conserved protein kinase Sch9 is a central player in the nutrient-induced signaling network in yeast, although only few of its direct substrates are known. We now provide evidence that Sch9 controls the vacuolar proton pump (V-ATPase) to maintain cellular pH homeostasis and ageing. A synthetic sick phenotype arises when deletion of SCH9 is combined with a dysfunctional V-ATPase, and the lack of Sch9 has a significant impact on cytosolic pH (pHc) homeostasis. Sch9 physically interacts with, and influences glucose-dependent assembly/disassembly of the V-ATPase, thereby integrating input from TORC1. Moreover, we show that the role of Sch9 in regulating ageing is tightly connected with V-ATPase activity and vacuolar acidity. As both Sch9 and the V-ATPase are highly conserved in higher eukaryotes, it will be interesting to further clarify their cooperative action on the cellular processes that influence growth and ageing. The evolutionary conserved TOR complex 1 controls growth in response to the quality and quantity of nutrients such as carbon and amino acids. The protein kinase Sch9 is the main TORC1 effector in yeast. However, only few of its direct targets are known. In this study, we performed a genome-wide screening looking for mutants which require Sch9 function for their survival and growth. In this way, we identified multiple components of the highly conserved vacuolar proton pump (V-ATPase) which mediates the luminal acidification of multiple biosynthetic and endocytic organelles. Besides a genetic interaction, we found Sch9 also physically interacts with the V-ATPase to regulate its assembly state in response to glucose availability and TORC1 activity. Moreover, the interaction with the V-ATPase has consequences for ageing as it allowed Sch9 to control vacuolar pH and thereby trigger either lifespan extension or lifespan shortening. Hence, our results provide insights into the signaling mechanism coupling glucose availability, TORC1 signaling, pH homeostasis and longevity. As both Sch9 and the V-ATPase are highly conserved and implicated in various pathologies, these results offer fertile ground for further research in higher eukaryotes.
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Mechanisms Underlying the Essential Role of Mitochondrial Membrane Lipids in Yeast Chronological Aging. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:2916985. [PMID: 28593023 PMCID: PMC5448074 DOI: 10.1155/2017/2916985] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 04/18/2017] [Indexed: 12/12/2022]
Abstract
The functional state of mitochondria is vital to cellular and organismal aging in eukaryotes across phyla. Studies in the yeast Saccharomyces cerevisiae have provided evidence that age-related changes in some aspects of mitochondrial functionality can create certain molecular signals. These signals can then define the rate of cellular aging by altering unidirectional and bidirectional communications between mitochondria and other organelles. Several aspects of mitochondrial functionality are known to impact the replicative and/or chronological modes of yeast aging. They include mitochondrial electron transport, membrane potential, reactive oxygen species, and protein synthesis and proteostasis, as well as mitochondrial synthesis of iron-sulfur clusters, amino acids, and NADPH. Our recent findings have revealed that the composition of mitochondrial membrane lipids is one of the key aspects of mitochondrial functionality affecting yeast chronological aging. We demonstrated that exogenously added lithocholic bile acid can delay chronological aging in yeast because it elicits specific changes in mitochondrial membrane lipids. These changes allow mitochondria to operate as signaling platforms that delay yeast chronological aging by orchestrating an institution and maintenance of a distinct cellular pattern. In this review, we discuss molecular and cellular mechanisms underlying the essential role of mitochondrial membrane lipids in yeast chronological aging.
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Blank HM, Perez R, He C, Maitra N, Metz R, Hill J, Lin Y, Johnson CD, Bankaitis VA, Kennedy BK, Aramayo R, Polymenis M. Translational control of lipogenic enzymes in the cell cycle of synchronous, growing yeast cells. EMBO J 2017; 36:487-502. [PMID: 28057705 PMCID: PMC5694946 DOI: 10.15252/embj.201695050] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 11/09/2016] [Accepted: 11/18/2016] [Indexed: 02/04/2023] Open
Abstract
Translational control during cell division determines when cells start a new cell cycle, how fast they complete it, the number of successive divisions, and how cells coordinate proliferation with available nutrients. The translational efficiencies of mRNAs in cells progressing synchronously through the mitotic cell cycle, while preserving the coupling of cell division with cell growth, remain uninvestigated. We now report comprehensive ribosome profiling of a yeast cell size series from the time of cell birth, to identify mRNAs under periodic translational control. The data reveal coordinate translational activation of mRNAs encoding lipogenic enzymes late in the cell cycle including Acc1p, the rate-limiting enzyme acetyl-CoA carboxylase. An upstream open reading frame (uORF) confers the translational control of ACC1 and adjusts Acc1p protein levels in different nutrients. The ACC1 uORF is relevant for cell division because its ablation delays cell cycle progression, reduces cell size, and suppresses the replicative longevity of cells lacking the Sch9p protein kinase regulator of ribosome biogenesis. These findings establish an unexpected relationship between lipogenesis and protein synthesis in mitotic cell divisions.
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Affiliation(s)
- Heidi M Blank
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Ricardo Perez
- Department of Biology, Texas A&M University, College Station, TX, USA
| | - Chong He
- The Buck Institute for Research on Aging, Novato, CA, USA
| | - Nairita Maitra
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Richard Metz
- Genomics and Bioinformatics Services, Texas A&M Agrilife Research, College Station, TX, USA
| | - Joshua Hill
- Genomics and Bioinformatics Services, Texas A&M Agrilife Research, College Station, TX, USA
| | - Yuhong Lin
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
| | - Charles D Johnson
- Genomics and Bioinformatics Services, Texas A&M Agrilife Research, College Station, TX, USA
| | - Vytas A Bankaitis
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
- Department of Molecular & Cellular Medicine, Texas A&M Health Sciences Center, College Station, TX, USA
- Department of Chemistry, Texas A&M University, College Station, TX, USA
| | | | - Rodolfo Aramayo
- Department of Biology, Texas A&M University, College Station, TX, USA
| | - Michael Polymenis
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
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General Amino Acid Control and 14-3-3 Proteins Bmh1/2 Are Required for Nitrogen Catabolite Repression-Sensitive Regulation of Gln3 and Gat1 Localization. Genetics 2016; 205:633-655. [PMID: 28007891 DOI: 10.1534/genetics.116.195800] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Accepted: 12/21/2016] [Indexed: 01/08/2023] Open
Abstract
Nitrogen catabolite repression (NCR), the ability of Saccharomyces cerevisiae to use good nitrogen sources in preference to poor ones, derives from nitrogen-responsive regulation of the GATA family transcription activators Gln3 and Gat1 In nitrogen-replete conditions, the GATA factors are cytoplasmic and NCR-sensitive transcription minimal. When only poor nitrogen sources are available, Gln3 is nuclear, dramatically increasing GATA factor-mediated transcription. This regulation was originally attributed to mechanistic Tor protein kinase complex 1 (mTorC1)-mediated control of Gln3 However, we recently showed that two regulatory systems act cumulatively to maintain cytoplasmic Gln3 sequestration, only one of which is mTorC1. Present experiments demonstrate that the other previously elusive component is uncharged transfer RNA-activated, Gcn2 protein kinase-mediated general amino acid control (GAAC). Gcn2 and Gcn4 are required for NCR-sensitive nuclear Gln3-Myc13 localization, and from epistasis experiments Gcn2 appears to function upstream of Ure2 Bmh1/2 are also required for nuclear Gln3-Myc13 localization and appear to function downstream of Ure2 Overall, Gln3 phosphorylation levels decrease upon loss of Gcn2, Gcn4, or Bmh1/2 Our results add a new dimension to nitrogen-responsive GATA-factor regulation and demonstrate the cumulative participation of the mTorC1 and GAAC pathways, which respond oppositely to nitrogen availability, in the nitrogen-responsive control of catabolic gene expression in yeast.
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Glucose Starvation Alters Heat Shock Response, Leading to Death of Wild Type Cells and Survival of MAP Kinase Signaling Mutant. PLoS One 2016; 11:e0165980. [PMID: 27870869 PMCID: PMC5117620 DOI: 10.1371/journal.pone.0165980] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 10/20/2016] [Indexed: 12/31/2022] Open
Abstract
A moderate heat shock induces Neurospora crassa to synthesize large quantities of heat shock proteins that are protective against higher, otherwise lethal temperatures. However, wild type cells do not survive when carbohydrate deprivation is added to heat shock. In contrast, a mutant strain defective in a stress-activated protein kinase does survive the combined stresses. In order to understand the basis for this difference in survival, we have determined the relative levels of detected proteins in the mutant and wild type strain during dual stress, and we have identified gene transcripts in both strains whose quantities change in response to heat shock or dual stress. These data and supportive experimental evidence point to reasons for survival of the mutant strain. By using alternative respiratory mechanisms, these cells experience less of the oxidative stress that proves damaging to wild type cells. Of central importance, mutant cells recycle limited resources during dual stress by undergoing autophagy, a process that we find utilized by both wild type and mutant cells during heat shock. Evidence points to inappropriate activation of TORC1, the central metabolic regulator, in wild type cells during dual stress, based upon behavior of an additional signaling mutant and inhibitor studies.
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Lu YJ, Swamy KBS, Leu JY. Experimental Evolution Reveals Interplay between Sch9 and Polyploid Stability in Yeast. PLoS Genet 2016; 12:e1006409. [PMID: 27812096 PMCID: PMC5094715 DOI: 10.1371/journal.pgen.1006409] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 10/06/2016] [Indexed: 12/20/2022] Open
Abstract
Polyploidization has crucial impacts on the evolution of different eukaryotic lineages including fungi, plants and animals. Recent genome data suggest that, for many polyploidization events, all duplicated chromosomes are maintained and genome reorganizations occur much later during evolution. However, newly-formed polyploid genomes are intrinsically unstable and often quickly degenerate into aneuploidy or diploidy. The transition between these two states remains enigmatic. In this study, laboratory evolution experiments were conducted to investigate this phenomenon. We show that robust tetraploidy is achieved in evolved yeast cells by increasing the abundance of Sch9—a protein kinase activated by the TORC1 (Target of Rapamycin Complex 1) and other signaling pathways. Overexpressing SCH9, but not TOR1, allows newly-formed tetraploids to exhibit evolved phenotypes and knocking out SCH9 diminishes the evolved phenotypes. Furthermore, when cells were challenged with conditions causing ancestral cells to evolve aneuploidy, tetraploidy was maintained in the evolved lines. Our results reveal a determinant role for Sch9 during the early stage of polyploid evolution. Polyploidy is frequently observed in eukaryotes, including in human liver cells and cancer. Evolutionary studies also suggest that polyploidy has contributed to species diversification and novel adaptation in fungi, plants and animals. However, artificially-constructed polyploids often display chromosome instability and quickly convert to aneuploids. This phenomenon conflicts with observations that many species derived from ancient genome duplications have maintained the extra number of chromosomes following polyploidization. What happened during the early stages of these polyploidy events that stabilized the duplicated genomes? We used laboratory evolution experiments to investigate this process. After being propagated in a rich medium at 23°C for 1000 generations, newly-constructed tetraploid yeast cells had evolved stable genomes. In addition, evolved cells acquired resistance to stresses specific to tetraploids and exhibited a more diploid-like transcriptome profile. Further analyses indicated that Sch9—the functional ortholog of mammalian S6 kinase involved in protein homeostasis, G1 progression, stress response and nutrient signaling—contributed to the evolved phenotypes. Evolved cells increased the protein abundance and stability of Sch9. Reconstitution experiments showed that overexpression of SCH9 enabled ancestral cells to display the evolved phenotypes and eliminating SCH9 diminished the evolved phenotypes. Finally, we show that evolved cells were able to maintain their genomes even under a condition that causes newly-formed tetraploids to evolve aneuploidy. Our results reveal that at the early stages after genome duplication, stable polyploidy can be achieved by fine-tuning a conserved key regulator coordinating multiple cellular processes.
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Affiliation(s)
- Yi-Jin Lu
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | | | - Jun-Yi Leu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
- * E-mail:
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Alves de Castro P, dos Reis TF, Dolan SK, Manfiolli AO, Brown NA, Jones GW, Doyle S, Riaño-Pachón DM, Squina FM, Caldana C, Singh A, Del Poeta M, Hagiwara D, Silva-Rocha R, Goldman GH. The Aspergillus fumigatus SchA SCH9 kinase modulates SakA HOG1 MAP kinase activity and it is essential for virulence. Mol Microbiol 2016; 102:642-671. [PMID: 27538790 PMCID: PMC5207228 DOI: 10.1111/mmi.13484] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2016] [Indexed: 02/06/2023]
Abstract
The serine-threonine kinase TOR, the Target of Rapamycin, is an important regulator of nutrient, energy and stress signaling in eukaryotes. Sch9, a Ser/Thr kinase of AGC family (the cAMP-dependent PKA, cGMP- dependent protein kinase G and phospholipid-dependent protein kinase C family), is a substrate of TOR. Here, we characterized the fungal opportunistic pathogen Aspergillus fumigatus Sch9 homologue (SchA). The schA null mutant was sensitive to rapamycin, high concentrations of calcium, hyperosmotic stress and SchA was involved in iron metabolism. The ΔschA null mutant showed increased phosphorylation of SakA, the A. fumigatus Hog1 homologue. The schA null mutant has increased and decreased trehalose and glycerol accumulation, respectively, suggesting SchA performs different roles for glycerol and trehalose accumulation during osmotic stress. The schA was transcriptionally regulated by osmotic stress and this response was dependent on SakA and MpkC. The double ΔschA ΔsakA and ΔschA ΔmpkC mutants were more sensitive to osmotic stress than the corresponding parental strains. Transcriptomics and proteomics identified direct and indirect targets of SchA post-exposure to hyperosmotic stress. Finally, ΔschA was avirulent in a low dose murine infection model. Our results suggest there is a complex network of interactions amongst the A. fumigatus TOR, SakA and SchA pathways.
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Affiliation(s)
- Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Thaila Fernanda dos Reis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Stephen K. Dolan
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Adriana Oliveira Manfiolli
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Neil Andrew Brown
- Plant Biology and Crop Science, Rothamsted Research, Harpenden, Herts AL5 2JQ, UK
| | - Gary W. Jones
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Sean Doyle
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Diego M. Riaño-Pachón
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Caixa Postal 6192, Campinas, São Paulo, CEP 13083-970, Brasil
| | - Fábio Márcio Squina
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Caixa Postal 6192, Campinas, São Paulo, CEP 13083-970, Brasil
| | - Camila Caldana
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Caixa Postal 6192, Campinas, São Paulo, CEP 13083-970, Brasil
- Max Planck Partner Group at Brazilian Bioethanol Science and Technology Laboratory, Brazilian Center for Research in Energy and Materials, São Paulo, Brazil
| | - Ashutosh Singh
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - Daisuke Hagiwara
- Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Rafael Silva-Rocha
- Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Gustavo H. Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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Exploring the power of yeast to model aging and age-related neurodegenerative disorders. Biogerontology 2016; 18:3-34. [PMID: 27804052 DOI: 10.1007/s10522-016-9666-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 10/24/2016] [Indexed: 12/12/2022]
Abstract
Aging is a multifactorial process determined by molecular, cellular and systemic factors and it is well established that advancing age is a leading risk factor for several neurodegenerative diseases. In fact, the close association of aging and neurodegenerative disorders has placed aging as the greatest social and economic challenge of the 21st century, and age-related diseases have also become a key priority for countries worldwide. The growing need to better understand both aging and neurodegenerative processes has led to the development of simple eukaryotic models amenable for mechanistic studies. Saccharomyces cerevisiae has proven to be an unprecedented experimental model to study the fundamental aspects of aging and to decipher the intricacies of neurodegenerative disorders greatly because the molecular mechanisms underlying these processes are evolutionarily conserved from yeast to human. Moreover, yeast offers several methodological advantages allowing a rapid and relatively easy way of establishing gene-protein-function associations. Here we review different aging theories, common cellular pathways driving aging and neurodegenerative diseases and discuss the major contributions of yeast to the state-of-art knowledge in both research fields.
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Pereira Silva L, Alves de Castro P, Dos Reis TF, Paziani MH, Von Zeska Kress MR, Riaño-Pachón DM, Hagiwara D, Ries LNA, Brown NA, Goldman GH. Genome-wide transcriptome analysis of Aspergillus fumigatus exposed to osmotic stress reveals regulators of osmotic and cell wall stresses that are SakA HOG1 and MpkC dependent. Cell Microbiol 2016; 19. [PMID: 27706915 DOI: 10.1111/cmi.12681] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 09/19/2016] [Accepted: 10/04/2016] [Indexed: 12/24/2022]
Abstract
Invasive aspergillosis is predominantly caused by Aspergillus fumigatus, and adaptations to stresses experienced within the human host are a prerequisite for the survival and virulence strategies of the pathogen. The central signal transduction pathway operating during hyperosmotic stress is the high osmolarity glycerol mitogen-activated protein kinase cascade. A. fumigatus MpkC and SakA, orthologues of the Saccharomyces cerevisiae Hog1p, constitute the primary regulator of the hyperosmotic stress response. We compared A. fumigatus wild-type transcriptional response to osmotic stress with the ΔmpkC, ΔsakA, and ΔmpkC ΔsakA strains. Our results strongly indicate that MpkC and SakA have independent and collaborative functions during the transcriptional response to transient osmotic stress. We have identified and characterized null mutants for four A. fumigatus basic leucine zipper proteins transcription factors. The atfA and atfB have comparable expression levels with the wild-type in ΔmpkC but are repressed in ΔsakA and ΔmpkC ΔsakA post-osmotic stress. The atfC and atfD have reduced expression levels in all mutants post-osmotic stress. The atfA-D null mutants displayed several phenotypes related to osmotic, oxidative, and cell wall stresses. The ΔatfA and ΔatfB were shown to be avirulent and to have attenuated virulence, respectively, in both Galleria mellonella and a neutropenic murine model of invasive pulmonary aspergillosis.
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Affiliation(s)
- Lilian Pereira Silva
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Thaila Fernanda Dos Reis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Mario Henrique Paziani
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | | | - Diego M Riaño-Pachón
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), São Paulo, Brazil
| | - Daisuke Hagiwara
- Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Laure N A Ries
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Neil Andrew Brown
- Plant Biology and Crop Science, Rothamsted Research, Harpenden, Hertfordshire, UK
| | - Gustavo H Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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Dakik P, Titorenko VI. Communications between Mitochondria, the Nucleus, Vacuoles, Peroxisomes, the Endoplasmic Reticulum, the Plasma Membrane, Lipid Droplets, and the Cytosol during Yeast Chronological Aging. Front Genet 2016; 7:177. [PMID: 27729926 PMCID: PMC5037234 DOI: 10.3389/fgene.2016.00177] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 09/16/2016] [Indexed: 12/14/2022] Open
Abstract
Studies employing the budding yeast Saccharomyces cerevisiae as a model organism have provided deep insights into molecular mechanisms of cellular and organismal aging in multicellular eukaryotes and have demonstrated that the main features of biological aging are evolutionarily conserved. Aging in S. cerevisiae is studied by measuring replicative or chronological lifespan. Yeast replicative aging is likely to model aging of mitotically competent human cell types, while yeast chronological aging is believed to mimic aging of post-mitotic human cell types. Emergent evidence implies that various organelle-organelle and organelle-cytosol communications play essential roles in chronological aging of S. cerevisiae. The molecular mechanisms underlying the vital roles of intercompartmental communications in yeast chronological aging have begun to emerge. The scope of this review is to critically analyze recent progress in understanding such mechanisms. Our analysis suggests a model for how temporally and spatially coordinated movements of certain metabolites between various cellular compartments impact yeast chronological aging. In our model, diverse changes in these key metabolites are restricted to critical longevity-defining periods of chronological lifespan. In each of these periods, a limited set of proteins responds to such changes of the metabolites by altering the rate and efficiency of a certain cellular process essential for longevity regulation. Spatiotemporal dynamics of alterations in these longevity-defining cellular processes orchestrates the development and maintenance of a pro- or anti-aging cellular pattern.
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Affiliation(s)
- Pamela Dakik
- Department of Biology, Faculty of Arts and Science, Concordia University Montreal, PQ, Canada
| | - Vladimir I Titorenko
- Department of Biology, Faculty of Arts and Science, Concordia University Montreal, PQ, Canada
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Oma1 Links Mitochondrial Protein Quality Control and TOR Signaling To Modulate Physiological Plasticity and Cellular Stress Responses. Mol Cell Biol 2016; 36:2300-12. [PMID: 27325672 DOI: 10.1128/mcb.00156-16] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 06/09/2016] [Indexed: 12/17/2022] Open
Abstract
A network of conserved proteases known as the intramitochondrial quality control (IMQC) system is central to mitochondrial protein homeostasis and cellular health. IMQC proteases also appear to participate in establishment of signaling cues for mitochondrion-to-nucleus communication. However, little is known about this process. Here, we show that in Saccharomyces cerevisiae, inactivation of the membrane-bound IMQC protease Oma1 interferes with oxidative-stress responses through enhanced production of reactive oxygen species (ROS) during logarithmic growth and reduced stress signaling via the TORC1-Rim15-Msn2/Msn4 axis. Pharmacological or genetic prevention of ROS accumulation in Oma1-deficient cells restores this defective TOR signaling. Additionally, inactivation of the Oma1 ortholog in the human fungal pathogen Candida albicans also alters TOR signaling and, unexpectedly, leads to increased resistance to neutrophil killing and virulence in the invertebrate animal model Galleria mellonella Our findings reveal a novel and evolutionarily conserved link between IMQC and TOR-mediated signaling that regulates physiological plasticity and pancellular oxidative-stress responses.
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Petitjean M, Teste MA, Léger-Silvestre I, François JM, Parrou JL. RETRACTED:A new function for the yeast trehalose-6P synthase (Tps1) protein, as key pro-survival factor during growth, chronological ageing, and apoptotic stress. Mech Ageing Dev 2016; 161:234-246. [PMID: 27507670 DOI: 10.1016/j.mad.2016.07.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 07/20/2016] [Accepted: 07/25/2016] [Indexed: 12/20/2022]
Abstract
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).
This article has been retracted at the request of Marie-Ange Teste, Isabelle Léger-Silvestre, Jean M François and Jean-Luc Parrou. Marjorie Petitjean could not be reached.
The corresponding author identified major issues and brought them to the attention of the Journal.
These issues span from significant errors in the Material and Methods section of the article and major flaws in cytometry data analysis to data fabrication on the part of one of the authors.
Given these errors, the retracting authors state that the only responsible course of action would be to retract the article, to respect scientific integrity and maintain the standards and rigor of literature from the retracting authors' group as well as the Journal.
The retracting authors sincerely apologize to the readers and editors.
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Affiliation(s)
| | - Marie-Ange Teste
- LISBP, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Isabelle Léger-Silvestre
- Laboratoire de Biologie Moléculaire Eucaryote, CNRS, Université de Toulouse, 118 route de Narbonne, F-31000 Toulouse, France
| | - Jean M François
- LISBP, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Jean-Luc Parrou
- LISBP, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France.
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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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50
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Qie B, Lyu Z, Lyu L, Liu J, Gao X, Liu Y, Duan W, Zhang N, Du L, Liu K. Sch9 regulates intracellular protein ubiquitination by controlling stress responses. Redox Biol 2015; 5:290-300. [PMID: 26087116 PMCID: PMC4477112 DOI: 10.1016/j.redox.2015.06.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 06/02/2015] [Accepted: 06/03/2015] [Indexed: 12/04/2022] Open
Abstract
Protein ubiquitination and the subsequent degradation are important means by which aberrant proteins are removed from cells, a key requirement for long-term survival. In this study, we found that the overall level of ubiquitinated proteins dramatically decreased as yeast cell grew from log to stationary phase. Deletion of SCH9, a gene encoding a key protein kinase for longevity control, decreased the level of ubiquitinated proteins in log phase and this effect could be reversed by restoring Sch9 function. We demonstrate here that the decrease of ubiquitinated proteins in sch9Δ cells in log phase is not caused by changes in ubiquitin expression, proteasome activity, or autophagy, but by enhanced expression of stress response factors and a decreased level of oxidative stress. Our results revealed for the first time how Sch9 regulates the level of ubiquitinated proteins and provides new insight into how Sch9 controls longevity.
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Affiliation(s)
- Beibei Qie
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China
| | - Zhou Lyu
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China
| | - Lei Lyu
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China
| | - Jun Liu
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China
| | - Xuejie Gao
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China
| | - Yanyan Liu
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China
| | - Wei Duan
- School of Medicine, Faculty of Health, Deakin University, Waurn Ponds, Victoria, Australia
| | - Nianhui Zhang
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China.
| | - Linfang Du
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China.
| | - Ke Liu
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China.
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