1
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Putnam CD. Loss of mitochondrial DNA is associated with reduced DNA content variability in Saccharomyces cerevisiae. MICROPUBLICATION BIOLOGY 2024; 2024:10.17912/micropub.biology.001117. [PMID: 38533353 PMCID: PMC10964099 DOI: 10.17912/micropub.biology.001117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 02/20/2024] [Accepted: 03/07/2024] [Indexed: 03/28/2024]
Abstract
DNA content measurement by fluorescence-assisted cell sorting (FACS) provides information on cell cycle progression and DNA content variability. Saccharomyces cerevisiae mutants with DNA content variability that was reduced relative to wild-type strains had defects in mitochondrial DNA (mtDNA) maintenance and mitochondrial gene expression and were correlated with strains found to lack mtDNA ([ rho 0 ] cells) by genome sequencing and fluorescence microscopy. In contrast, mutants with increased variability had defects in cell cycle progression, which may indicate a loss of coordination between mtDNA and nuclear DNA replication. Thus, FACS measurement of DNA content variability can provide insight into cell-to-cell heterogeneity in mtDNA copy number.
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Affiliation(s)
- Christopher D. Putnam
- Department of Medicine, University of California, San Diego, San Diego, California, United States
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2
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Sandell L, König SG, Otto SP. Schrödinger's yeast: the challenge of using transformation to compare fitness among Saccharomyces cerevisiae that differ in ploidy or zygosity. PeerJ 2023; 11:e16547. [PMID: 38077443 PMCID: PMC10704993 DOI: 10.7717/peerj.16547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 11/08/2023] [Indexed: 12/18/2023] Open
Abstract
How the number of genome copies modifies the effect of random mutations remains poorly known. In yeast, researchers have investigated these effects for knock-out or other large-effect mutations, but have not accounted for differences at the mating-type locus. We set out to compare fitness differences among strains that differ in ploidy and/or zygosity using a panel of spontaneously arising mutations acquired in haploid yeast from a previous study. To ensure no genetic differences, even at the mating-type locus, we embarked on a series of transformations, which first sterilized and then temporarily introduced plasmid-borne mating types. Despite these attempts to equalize the haplotypes, fitness variation introduced during transformation swamped the differences among the original mutation-accumulation lines. While colony size looked normal, we observed a bi-modality in the maximum growth rate of our transformed yeast and determined that many of the slow growing lines were respiratory deficient ("petite"). Not previously reported, we found that yeast that were TID1/RDH54 knockouts were less likely to become petite. Even for lines with the same petite status, however, we found no correlation in fitness between the two replicate transformations performed. These results pose a challenge for any study using transformation to measure the fitness effect of genetic differences among strains. By attempting to hold haplotypes constant, we introduced more mutations that overwhelmed our ability to measure fitness differences between the genetic states. In this study, we transformed over one hundred different lines of yeast, using two independent transformations, and found that this common laboratory procedure can cause large changes to the microbe studied. Our study provides a cautionary tale of the need to use multiple transformants in fitness assays.
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Affiliation(s)
- Linnea Sandell
- Department of Zoology and Biodiversity Research Center, University of British Columbia, Vancouver, Canada
| | - Stephan G. König
- Department of Zoology and Biodiversity Research Center, University of British Columbia, Vancouver, Canada
- Department of Computer Science, University of British Columbia, Vancouver, British Columbia, Canada
| | - Sarah P. Otto
- Department of Zoology and Biodiversity Research Center, University of British Columbia, Vancouver, Canada
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3
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Azbarova AV, Knorre DA. Role of Mitochondrial DNA in Yeast Replicative Aging. BIOCHEMISTRY. BIOKHIMIIA 2023; 88:1997-2006. [PMID: 38462446 DOI: 10.1134/s0006297923120040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 11/13/2023] [Accepted: 11/15/2023] [Indexed: 03/12/2024]
Abstract
Despite the diverse manifestations of aging across different species, some common aging features and underlying mechanisms are shared. In particular, mitochondria appear to be among the most vulnerable systems in both metazoa and fungi. In this review, we discuss how mitochondrial dysfunction is related to replicative aging in the simplest eukaryotic model, the baker's yeast Saccharomyces cerevisiae. We discuss a chain of events that starts from asymmetric distribution of mitochondria between mother and daughter cells. With age, yeast mother cells start to experience a decrease in mitochondrial transmembrane potential and, consequently, a decrease in mitochondrial protein import efficiency. This induces mitochondrial protein precursors in the cytoplasm, the loss of mitochondrial DNA (mtDNA), and at the later stages - cell death. Interestingly, yeast strains without mtDNA can have either increased or decreased lifespan compared to the parental strains with mtDNA. The direction of the effect depends on their ability to activate compensatory mechanisms preventing or mitigating negative consequences of mitochondrial dysfunction. The central role of mitochondria in yeast aging and death indicates that it is one of the most complex and, therefore, deregulation-prone systems in eukaryotic cells.
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Affiliation(s)
- Aglaia V Azbarova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Dmitry A Knorre
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia.
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4
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Campero-Basaldua C, González J, García JA, Ramírez E, Hernández H, Aguirre B, Torres-Ramírez N, Márquez D, Sánchez NS, Gómez-Hernández N, Torres-Machorro AL, Riego-Ruiz L, Scazzocchio C, González A. Neo-functionalization in Saccharomyces cerevisiae: a novel Nrg1-Rtg3 chimeric transcriptional modulator is essential to maintain mitochondrial DNA integrity. ROYAL SOCIETY OPEN SCIENCE 2023; 10:231209. [PMID: 37920568 PMCID: PMC10618058 DOI: 10.1098/rsos.231209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 10/11/2023] [Indexed: 11/04/2023]
Abstract
In Saccharomyces cerevisiae, the transcriptional repressor Nrg1 (Negative Regulator of Glucose-repressed genes) and the β-Zip transcription factor Rtg3 (ReTroGrade regulation) mediate glucose repression and signalling from the mitochondria to the nucleus, respectively. Here, we show a novel function of these two proteins, in which alanine promotes the formation of a chimeric Nrg1/Rtg3 regulator that represses the ALT2 gene (encoding an alanine transaminase paralog of unknown function). An NRG1/NRG2 paralogous pair, resulting from a post-wide genome small-scale duplication event, is present in the Saccharomyces genus. Neo-functionalization of only one paralog resulted in the ability of Nrg1 to interact with Rtg3. Both nrg1Δ and rtg3Δ single mutant strains were unable to use ethanol and showed a typical petite (small) phenotype on glucose. Neither of the wild-type genes complemented the petite phenotype, suggesting irreversible mitochondrial DNA damage in these mutants. Neither nrg1Δ nor rtg3Δ mutant strains expressed genes encoded by any of the five polycistronic units transcribed from mitochondrial DNA in S. cerevisiae. This, and the direct measurement of the mitochondrial DNA gene complement, confirmed that irreversible damage of the mitochondrial DNA occurred in both mutant strains, which is consistent with the essential role of the chimeric Nrg1/Rtg3 regulator in mitochondrial DNA maintenance.
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Affiliation(s)
- Carlos Campero-Basaldua
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular Universidad Nacional Autónoma de México, Ciudad de Mexi, México
| | - James González
- Laboratorio de Biología Molecular y Genómica, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de Mexico, México
| | - Janeth Alejandra García
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular Universidad Nacional Autónoma de México, Ciudad de Mexi, México
| | - Edgar Ramírez
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular Universidad Nacional Autónoma de México, Ciudad de Mexi, México
| | - Hugo Hernández
- Departamento de Biología, Facultad de Química, UNAM, México City, Universidad Nacional Autónoma de México, Ciudad de Mexico, México
| | - Beatriz Aguirre
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular Universidad Nacional Autónoma de México, Ciudad de Mexi, México
| | - Nayeli Torres-Ramírez
- Laboratorio de Microscopía Electrónica Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de Mexico, México
| | - Dariel Márquez
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular Universidad Nacional Autónoma de México, Ciudad de Mexi, México
| | - Norma Silvia Sánchez
- Departamento de Genética Molecular, Instituto de Fisiología Celular Universidad Nacional Autónoma de México, Ciudad de Mexi, México
| | - Nicolás Gómez-Hernández
- División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), San Luis Potosí, SLP, México
| | - Ana Lilia Torres-Machorro
- Laboratorio de Biología Celular, Departamento de Investigación en Fibrosis Pulmonar, Instituto Nacional de Enfermedades Respiratorias ‘Ismael Cosío Villegas', Tlalpan, Mexico
| | - Lina Riego-Ruiz
- División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), San Luis Potosí, SLP, México
| | - Claudio Scazzocchio
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Alicia González
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular Universidad Nacional Autónoma de México, Ciudad de Mexi, México
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5
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Turco G, Chang C, Wang RY, Kim G, Stoops EH, Richardson B, Sochat V, Rust J, Oughtred R, Thayer N, Kang F, Livstone MS, Heinicke S, Schroeder M, Dolinski KJ, Botstein D, Baryshnikova A. Global analysis of the yeast knockout phenome. SCIENCE ADVANCES 2023; 9:eadg5702. [PMID: 37235661 PMCID: PMC11326039 DOI: 10.1126/sciadv.adg5702] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 04/20/2023] [Indexed: 05/28/2023]
Abstract
Genome-wide phenotypic screens in the budding yeast Saccharomyces cerevisiae, enabled by its knockout collection, have produced the largest, richest, and most systematic phenotypic description of any organism. However, integrative analyses of this rich data source have been virtually impossible because of the lack of a central data repository and consistent metadata annotations. Here, we describe the aggregation, harmonization, and analysis of ~14,500 yeast knockout screens, which we call Yeast Phenome. Using this unique dataset, we characterized two unknown genes (YHR045W and YGL117W) and showed that tryptophan starvation is a by-product of many chemical treatments. Furthermore, we uncovered an exponential relationship between phenotypic similarity and intergenic distance, which suggests that gene positions in both yeast and human genomes are optimized for function.
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Affiliation(s)
- Gina Turco
- Calico Life Sciences LLC, South San Francisco, CA, USA
| | - Christie Chang
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | | | - Griffin Kim
- Calico Life Sciences LLC, South San Francisco, CA, USA
| | | | - Brianna Richardson
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Vanessa Sochat
- Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Jennifer Rust
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Rose Oughtred
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | | | - Fan Kang
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Michael S Livstone
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Sven Heinicke
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Mark Schroeder
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Kara J Dolinski
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
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6
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Nguyen THM, Tinz-Burdick A, Lenhardt M, Geertz M, Ramirez F, Schwartz M, Toledano M, Bonney B, Gaebler B, Liu W, Wolters JF, Chiu K, Fiumera AC, Fiumera HL. Mapping mitonuclear epistasis using a novel recombinant yeast population. PLoS Genet 2023; 19:e1010401. [PMID: 36989278 PMCID: PMC10085025 DOI: 10.1371/journal.pgen.1010401] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 04/10/2023] [Accepted: 03/10/2023] [Indexed: 03/30/2023] Open
Abstract
Genetic variation in mitochondrial and nuclear genomes can perturb mitonuclear interactions and lead to phenotypic differences between individuals and populations. Despite their importance to most complex traits, it has been difficult to identify the interacting mitonuclear loci. Here, we present a novel advanced intercrossed population of Saccharomyces cerevisiae yeasts, called the Mitonuclear Recombinant Collection (MNRC), designed explicitly for detecting mitonuclear loci contributing to complex traits. For validation, we focused on mapping genes that contribute to the spontaneous loss of mitochondrial DNA (mtDNA) that leads to the petite phenotype in yeast. We found that rates of petite formation in natural populations are variable and influenced by genetic variation in nuclear DNA, mtDNA and mitonuclear interactions. We mapped nuclear and mitonuclear alleles contributing to mtDNA stability using the MNRC by integrating a term for mitonuclear epistasis into a genome-wide association model. We found that the associated mitonuclear loci play roles in mitotic growth most likely responding to retrograde signals from mitochondria, while the associated nuclear loci with main effects are involved in genome replication. We observed a positive correlation between growth rates and petite frequencies, suggesting a fitness tradeoff between mitotic growth and mtDNA stability. We also found that mtDNA stability was correlated with a mobile mitochondrial GC-cluster that is present in certain populations of yeast and that selection for nuclear alleles that stabilize mtDNA may be rapidly occurring. The MNRC provides a powerful tool for identifying mitonuclear interacting loci that will help us to better understand genotype-phenotype relationships and coevolutionary trajectories.
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Affiliation(s)
- Tuc H M Nguyen
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
- Department of Biological Sciences, New York University, New York, New York, United States of America
| | - Austen Tinz-Burdick
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Meghan Lenhardt
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Margaret Geertz
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Franchesca Ramirez
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Mark Schwartz
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Michael Toledano
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Brooke Bonney
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Benjamin Gaebler
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Weiwei Liu
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - John F Wolters
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Kenneth Chiu
- Department of Computer Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Anthony C Fiumera
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Heather L Fiumera
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
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7
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Synthetic negative genome screen of the GPN-loop GTPase NPA3 in Saccharomyces cerevisiae. Curr Genet 2022; 68:343-360. [PMID: 35660944 DOI: 10.1007/s00294-022-01243-1] [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: 12/27/2021] [Revised: 04/21/2022] [Accepted: 04/30/2022] [Indexed: 11/03/2022]
Abstract
The GPN-loop GTPase Npa3 is encoded by an essential gene in the yeast Saccharomyces cerevisiae. Npa3 plays a critical role in the assembly and nuclear accumulation of RNA polymerase II (RNAPII), a function that may explain its essentiality. Genetic interactions describe the extent to which a mutation in a particular gene affects a specific phenotype when co-occurring with an alteration in a second gene. Discovering synthetic negative genetic interactions has long been used as a tool to delineate the functional relatedness between pairs of genes participating in common or compensatory biological pathways. Previously, our group showed that nuclear targeting and transcriptional activity of RNAPII were unaffected in cells expressing exclusively a C-terminal truncated mutant version of Npa3 (npa3∆C) lacking the last 106 residues naturally absent from the single GPN protein in Archaea, but universally conserved in all Npa3 orthologs of eukaryotes. To gain insight into novel cellular functions for Npa3, we performed here a genome-wide Synthetic Genetic Array (SGA) study coupled to bulk fluorescence monitoring to identify negative genetic interactions of NPA3 by crossing an npa3∆C strain with a 4,389 nonessential gene-deletion collection. This genetic screen revealed previously unknown synthetic negative interactions between NPA3 and 15 genes. Our results revealed that the Npa3 C-terminal tail extension regulates the participation of this essential GTPase in previously unknown biological processes related to mitochondrial homeostasis and ribosome biogenesis.
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8
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Ishikawa Y, Nishino S, Fukuda S, Nguyet VTA, Izawa S. Severe ethanol stress induces the preferential synthesis of mitochondrial disaggregase Hsp78 and formation of DUMPs in Saccharomyces cerevisiae. Biochim Biophys Acta Gen Subj 2022; 1866:130147. [DOI: 10.1016/j.bbagen.2022.130147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/24/2022] [Accepted: 04/05/2022] [Indexed: 01/10/2023]
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9
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Abstract
Mitochondria are complex organelles with two membranes. Their architecture is determined by characteristic folds of the inner membrane, termed cristae. Recent studies in yeast and other organisms led to the identification of four major pathways that cooperate to shape cristae membranes. These include dimer formation of the mitochondrial ATP synthase, assembly of the mitochondrial contact site and cristae organizing system (MICOS), inner membrane remodelling by a dynamin-related GTPase (Mgm1/OPA1), and modulation of the mitochondrial lipid composition. In this review, we describe the function of the evolutionarily conserved machineries involved in mitochondrial cristae biogenesis with a focus on yeast and present current models to explain how their coordinated activities establish mitochondrial membrane architecture.
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Affiliation(s)
- Till Klecker
- Institut für Zellbiologie, Universität Bayreuth, 95440 Bayreuth, Germany
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10
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Mercurio K, Singh D, Walden E, Baetz K. Global analysis of Saccharomyces cerevisiae growth in mucin. G3 (BETHESDA, MD.) 2021; 11:jkab294. [PMID: 34849793 PMCID: PMC8527512 DOI: 10.1093/g3journal/jkab294] [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: 03/10/2021] [Accepted: 08/03/2021] [Indexed: 11/12/2022]
Abstract
Metagenomic profiling of the human gut microbiome has discovered DNA from dietary yeasts like Saccharomyces cerevisiae. However, it is unknown if the S. cerevisiae detected by common metagenomic methods are from dead dietary sources, or from live S. cerevisiae colonizing the gut similar to their close relative Candida albicans. While S. cerevisiae can adapt to minimal oxygen and acidic environments, it has not been explored whether this yeast can metabolize mucin, the large, gel-forming, highly glycosylated proteins representing a major source of carbon in the gut mucosa. We reveal that S. cerevisiae can utilize mucin as their main carbon source, as well as perform both a transcriptome analysis and a chemogenomic screen to identify biological pathways required for this yeast to grow optimally in mucin. In total, 739 genes demonstrate significant differential expression in mucin culture, and deletion of 21 genes impact growth in mucin. Both screens suggest that mitochondrial function is required for proper growth in mucin, and through secondary assays we determine that mucin exposure induces mitogenesis and cellular respiration. We further show that deletion of an uncharacterized ORF, YCR095W-A, led to dysfunction in mitochondrial morphology and oxygen consumption in mucin. Finally, we demonstrate that Yps7, an aspartyl protease and homolog to mucin-degrading proteins in C. albicans, is important for growth on mucin. Collectively, our work serves as the initial step toward establishing how this common dietary fungus can survive in the mucus environment of the human gut.
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Affiliation(s)
- Kevin Mercurio
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Dylan Singh
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Elizabeth Walden
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Kristin Baetz
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON K1H 8M5, Canada
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11
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Dorweiler JE, Manogaran AL. Cytoduction and Plasmiduction in Yeast. Bio Protoc 2021; 11:e4146. [PMID: 34604451 DOI: 10.21769/bioprotoc.4146] [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: 02/17/2021] [Revised: 05/10/2021] [Accepted: 05/17/2021] [Indexed: 11/02/2022] Open
Abstract
Cytoduction, and a related technique referred to as plasmiduction, have facilitated substantial advancements in the field of yeast prion biology by providing a streamlined method of transferring prions from one yeast strain to another. Prions are cytoplasmic elements consisting of aggregated misfolded proteins, and as such, they exhibit non-Mendelian patterns of inheritance. While prion transfer through mating and sporulation, or through protein transformation, is possible, these approaches yield non-isogenic strains or are technically complex, respectively. Cytoduction is a mating-based technique that takes advantage of a kar1 mutation with impaired nuclear fusion (karyogamy). It is a straightforward method for introducing a prion to any yeast strain (referred to as the recipient) by mating it with a donor strain containing the prion of interest. The only absolute requirement is that one of these two strains (donor or recipient) must carry the kar1-1 mutation to limit nuclear fusion. The resulting cytoductant contains the original nucleus of the recipient strain, but a cytoplasm reflecting a mix of all elements from the donor and the recipient. Modifications to the basic cytoduction strategy provide several options for successful cytoduction, including when working with slow growing or respiratory deficient strains. A significant advantage of the plasmiduction protocol presented is the ability to transfer a plasmid encoding a fluorescently tagged version of the prion protein, which allows for the direct verification of the prion state through visual protein aggregates. Graphic abstract: Transfer of Yeast Cytoplasmic Elements such as Prions using Cytoduction.
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Affiliation(s)
- Jane E Dorweiler
- Department of Biological Sciences, Marquette University, Milwaukee, WI, USA
| | - Anita L Manogaran
- Department of Biological Sciences, Marquette University, Milwaukee, WI, USA
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12
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Garza NM, Griffin AT, Zulkifli M, Qiu C, Kaplan CD, Gohil VM. A genome-wide copper-sensitized screen identifies novel regulators of mitochondrial cytochrome c oxidase activity. J Biol Chem 2021; 296:100485. [PMID: 33662401 PMCID: PMC8027276 DOI: 10.1016/j.jbc.2021.100485] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/22/2021] [Accepted: 02/25/2021] [Indexed: 11/30/2022] Open
Abstract
Copper is essential for the activity and stability of cytochrome c oxidase (CcO), the terminal enzyme of the mitochondrial respiratory chain. Loss-of-function mutations in genes required for copper transport to CcO result in fatal human disorders. Despite the fundamental importance of copper in mitochondrial and organismal physiology, systematic identification of genes that regulate mitochondrial copper homeostasis is lacking. To discover these genes, we performed a genome-wide screen using a library of DNA-barcoded yeast deletion mutants grown in copper-supplemented media. Our screen recovered a number of genes known to be involved in cellular copper homeostasis as well as genes previously not linked to mitochondrial copper biology. These newly identified genes include the subunits of the adaptor protein 3 complex (AP-3) and components of the cellular pH-sensing pathway Rim20 and Rim21, both of which are known to affect vacuolar function. We find that AP-3 and Rim mutants exhibit decreased vacuolar acidity, which in turn perturbs mitochondrial copper homeostasis and CcO function. CcO activity of these mutants could be rescued by either restoring vacuolar pH or supplementing growth media with additional copper. Consistent with these genetic data, pharmacological inhibition of the vacuolar proton pump leads to decreased mitochondrial copper content and a concomitant decrease in CcO abundance and activity. Taken together, our study uncovered novel genetic regulators of mitochondrial copper homeostasis and provided a mechanism by which vacuolar pH impacts mitochondrial respiration through copper homeostasis.
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Affiliation(s)
- Natalie M Garza
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Aaron T Griffin
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Mohammad Zulkifli
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Chenxi Qiu
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Craig D Kaplan
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Vishal M Gohil
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA.
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13
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Das D, Sarkar H, Podder S. In silico identification of key regulators instigating the pre-meiotic phase during respiration in Saccharomyces cerevisiae. FEMS Yeast Res 2021; 21:6152269. [PMID: 33640958 DOI: 10.1093/femsyr/foab006] [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: 10/28/2020] [Accepted: 02/04/2021] [Indexed: 10/22/2022] Open
Abstract
Like higher eukaryotes, diploid MATa/MATα budding yeasts can undergo both mitosis and meiosis. Although the potential reason for their phase switching is elucidated by two consecutive processes, i.e. transition from fermentation (mitotic growth) to respiration in glucose-deficient media and then complete shift to meiotic phase in combined nitrogen- and glucose-starved media, the genomic interactions and regulatory cascade operating this drive remain elusive. Here, we aim to explore the regulatory cross-talk that mediates the phase transition. We have hypothesized that pre-growth in glucose-starved condition (yeast extract-peptone-acetate media) not only causes switch from fermentation to respiration but also prepares them for meiosis via a myriad of signaling events regulated by transcription factors (TFs). We have identified 23 putative TFs from integrated protein-protein interaction and gene regulatory network that were reconstructed from predicted and experimentally validated data. A total of six TFs (Xbp1p, Abf1p, Cbf1p, Ste12p, Reb1p and Gcn4p) are found to be highly connected in the network and involved in the cross-talk between respiration and cellular preparation for meiosis. We have identified Abf1p and Adr1p as the master regulators of the integrated network. This study in yeast will help to decipher the pre-meiotic initiation that occurs in higher eukaryotes.
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Affiliation(s)
- Deepyaman Das
- Department of Microbiology, Raiganj University, Raiganj, Uttar Dinajpur 733134, West Bengal, India
| | - Hironmoy Sarkar
- Department of Microbiology, Raiganj University, Raiganj, Uttar Dinajpur 733134, West Bengal, India
| | - Soumita Podder
- Department of Microbiology, Raiganj University, Raiganj, Uttar Dinajpur 733134, West Bengal, India
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Ravoitytė B, Lukša J, Yurchenko V, Serva S, Servienė E. Saccharomyces paradoxus Transcriptional Alterations in Cells of Distinct Phenotype and Viral dsRNA Content. Microorganisms 2020; 8:microorganisms8121902. [PMID: 33266158 PMCID: PMC7761358 DOI: 10.3390/microorganisms8121902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 11/28/2020] [Accepted: 11/29/2020] [Indexed: 01/23/2023] Open
Abstract
Killer yeasts are attractive antifungal agents with great potential applications in the food industry. Natural Saccharomyces paradoxus isolates provide new dsRNA-based killer systems available for investigation. The presence of viral dsRNA may alter transcriptional profile of S. paradoxus. To test this possibility, a high-throughput RNA sequencing was employed to compare the transcriptomes of S. paradoxus AML 15-66 K66 killer strains after curing them of either M-66 alone or both M-66 and L-A-66 dsRNA viruses. The S. paradoxus cells cured of viral dsRNA(s) showed respiration deficient or altered sporulation patterns. We have identified numerous changes in the transcription profile of genes including those linked to ribosomes and amino acid biosynthesis, as well as mitochondrial function. Our work advance studies of transcriptional adaptations of Saccharomyces spp. induced by changes in phenotype and set of dsRNA viruses, reported for the first time.
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Affiliation(s)
- Bazilė Ravoitytė
- Laboratory of Genetics, Institute of Botany, Nature Research Centre, Akademijos str. 2, 08412 Vilnius, Lithuania;
- Correspondence: (B.R.); (E.S.)
| | - Juliana Lukša
- Laboratory of Genetics, Institute of Botany, Nature Research Centre, Akademijos str. 2, 08412 Vilnius, Lithuania;
| | - Vyacheslav Yurchenko
- Life Science Research Centre, Faculty of Science, University of Ostrava, Chittussiho 10, 710 00 Ostrava, Czech Republic;
- Martsinovsky Institute of Medical Parasitology, Tropical and Vector Borne Diseases, Sechenov University, Malaya Pirogovskaya str. 20, 119435 Moscow, Russia
| | - Saulius Serva
- Department of Biochemistry and Molecular Biology, Institute of Biosciences, Vilnius University, Saulėtekio al. 7, 10257 Vilnius, Lithuania;
- Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Saulėtekio al. 11, 10223 Vilnius, Lithuania
| | - Elena Servienė
- Laboratory of Genetics, Institute of Botany, Nature Research Centre, Akademijos str. 2, 08412 Vilnius, Lithuania;
- Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Saulėtekio al. 11, 10223 Vilnius, Lithuania
- Correspondence: (B.R.); (E.S.)
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