1
|
Saha D, Gregor JB, Hoda S, Eastman KE, Navarrete M, Wisecaver JH, Briggs SD. Candida glabrata maintains two Hap1 homologs, Zcf27 and Zcf4, for distinct roles in ergosterol gene regulation to mediate sterol homeostasis under azole and hypoxic conditions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.20.599910. [PMID: 38979343 PMCID: PMC11230168 DOI: 10.1101/2024.06.20.599910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Candida glabrata exhibits innate resistance to azole antifungal drugs but also has the propensity to rapidly develop clinical drug resistance. Azole drugs, which target Erg11, is one of the three major classes of antifungals used to treat Candida infections. Despite their widespread use, the mechanism controlling azole-induced ERG gene expression and drug resistance in C. glabrata has primarily revolved around Upc2 and/or Pdr1. In this study, we determined the function of two zinc cluster transcription factors, Zcf27 and Zcf4, as direct but distinct regulators of ERG genes. Our phylogenetic analysis revealed C. glabrata Zcf27 and Zcf4 as the closest homologs to Saccharomyces cerevisiae Hap1. Hap1 is a known zinc cluster transcription factor in S. cerevisiae in controlling ERG gene expression under aerobic and hypoxic conditions. Interestingly, when we deleted HAP1 or ZCF27 in either S. cerevisiae or C. glabrata, respectively, both deletion strains showed altered susceptibility to azole drugs, whereas the strain deleted for ZCF4 did not exhibit azole susceptibility. We also determined that the increased azole susceptibility in a zcf27Δ strain is attributed to decreased azole-induced expression of ERG genes, resulting in decreased levels of total ergosterol. Surprisingly, Zcf4 protein expression is barely detected under aerobic conditions but is specifically induced under hypoxic conditions. However, under hypoxic conditions, Zcf4 but not Zcf27 was directly required for the repression of ERG genes. This study provides the first demonstration that Zcf27 and Zcf4 have evolved to serve distinct roles allowing C. glabrata to adapt to specific host and environmental conditions.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Scott D. Briggs
- Department of Biochemistry
- Purdue University Institute for Cancer Research
| |
Collapse
|
2
|
Zeng DW, Yang YQ, Wang Q, Zhang FL, Zhang MD, Liao S, Liu ZQ, Fan YC, Liu CG, Zhang L, Zhao XQ. Transcriptome analysis of Kluyveromyces marxianus under succinic acid stress and development of robust strains. Appl Microbiol Biotechnol 2024; 108:293. [PMID: 38592508 PMCID: PMC11003901 DOI: 10.1007/s00253-024-13097-3] [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: 10/17/2023] [Revised: 02/22/2024] [Accepted: 02/28/2024] [Indexed: 04/10/2024]
Abstract
Kluyveromyces marxianus has become an attractive non-conventional yeast cell factory due to its advantageous properties such as high thermal tolerance and rapid growth. Succinic acid (SA) is an important platform molecule that has been applied in various industries such as food, material, cosmetics, and pharmaceuticals. SA bioproduction may be compromised by its toxicity. Besides, metabolite-responsive promoters are known to be important for dynamic control of gene transcription. Therefore, studies on global gene transcription under various SA concentrations are of great importance. Here, comparative transcriptome changes of K. marxianus exposed to various concentrations of SA were analyzed. Enrichment and analysis of gene clusters revealed repression of the tricarboxylic acid cycle and glyoxylate cycle, also activation of the glycolysis pathway and genes related to ergosterol synthesis. Based on the analyses, potential SA-responsive promoters were investigated, among which the promoter strength of IMTCP2 and KLMA_50231 increased 43.4% and 154.7% in response to 15 g/L SA. In addition, overexpression of the transcription factors Gcr1, Upc2, and Ndt80 significantly increased growth under SA stress. Our results benefit understanding SA toxicity mechanisms and the development of robust yeast for organic acid production. KEY POINTS: • Global gene transcription of K. marxianus is changed by succinic acid (SA) • Promoter activities of IMTCP2 and KLMA_50123 are regulated by SA • Overexpression of Gcr1, Upc2, and Ndt80 enhanced SA tolerance.
Collapse
Affiliation(s)
- Du-Wen Zeng
- Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yong-Qiang Yang
- School of Life Sciences, Hainan University, Haikou, 570228, China
| | - Qi Wang
- Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Feng-Li Zhang
- Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Mao-Dong Zhang
- Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Sha Liao
- SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Co., Ltd, Dalian, 116045, China
| | - Zhi-Qiang Liu
- School of Life Sciences, Hainan University, Haikou, 570228, China
| | - Ya-Chao Fan
- SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Co., Ltd, Dalian, 116045, China
| | - Chen-Guang Liu
- Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Lin Zhang
- SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Co., Ltd, Dalian, 116045, China.
| | - Xin-Qing Zhao
- Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China.
| |
Collapse
|
3
|
Lewis AG, Carmichael L, Wang RY, Gibney PA. Characterizing a panel of amino acid auxotrophs under auxotrophic starvation conditions. Yeast 2024; 41:5-18. [PMID: 37997284 DOI: 10.1002/yea.3910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/20/2023] [Accepted: 11/09/2023] [Indexed: 11/25/2023] Open
Abstract
Auxotrophic strains starving for their cognate nutrient, termed auxotrophic starvation, are characterized by a shorter lifespan, higher glucose wasting phenotype, and inability to accomplish cell cycle arrest when compared to a "natural starvation," where a cell is starving for natural environmental growth-limiting nutrients such as phosphate. Since evidence of this physiological response is limited to only a subset of auxotrophs, we evaluated a panel of auxotrophic mutants to determine whether these responses are characteristic of a broader range of amino acid auxotrophs. Based on the starvation survival kinetics, the panel of strains was grouped into three categories-short-lived strains, strains with survival similar to a prototrophic wild type strain, and long-lived strains. Among the short-lived strains, we observed that the tyrosine, asparagine, threonine, and aspartic acid auxotrophs rapidly decline in viability, with all strains unable to arrest cell cycle progression. The three basic amino acid auxotrophs had a survival similar to a prototrophic strain starving in minimal media. The leucine, tryptophan, methionine, and cysteine auxotrophs displayed the longest lifespan. We also demonstrate how the phenomenon of glucose wasting is limited to only a subset of the tested auxotrophs, namely the asparagine, leucine, and lysine auxotrophs. Furthermore, we observed pleiotropic phenotypes associated with a subgroup of auxotrophs, highlighting the importance of considering unintended phenotypic effects when using auxotrophic strains especially in chronological aging experiments.
Collapse
Affiliation(s)
- Alisha G Lewis
- Department of Food Science, Cornell University, Ithaca, New York, USA
| | - Laurin Carmichael
- Department of Food Science, Cornell University, Ithaca, New York, USA
| | - Rebecca Y Wang
- Calico Life Sciences LLC, South San Francisco, California, USA
| | - Patrick A Gibney
- Department of Food Science, Cornell University, Ithaca, New York, USA
| |
Collapse
|
4
|
Chen A, Gibney PA. Disruption of GRR1 in Saccharomyces cerevisiae rescues tps1Δ growth on fermentable carbon sources. MICROPUBLICATION BIOLOGY 2023; 2023:10.17912/micropub.biology.000927. [PMID: 37602281 PMCID: PMC10436075 DOI: 10.17912/micropub.biology.000927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 07/31/2023] [Accepted: 07/31/2023] [Indexed: 08/22/2023]
Abstract
In Saccharomyces cerevisiae , trehalose-6-phosphate synthase (Tps1) catalyzes the formation of trehalose-6-phophate in trehalose synthesis. Deletion of the TPS1 gene is associated with phenotypes including inability to grow on fermentable carbon sources, survive at elevated temperatures, or sporulate. To further understand these pleiotropic phenotypes, we conducted a genetic suppressor screen and identified a novel suppressor, grr1 Δ, able to restore tps1 Δ growth on rapidly fermentable sugars. However, disruption of GRR1 did not rescue tps1 Δ thermosensitivity. These results support the model that trehalose metabolism has important roles in regulating glucose sensing and signaling in addition to regulating stress resistance.
Collapse
Affiliation(s)
- Anqi Chen
- Department of Food Science, Cornell University, Ithaca, New York, United States
- Science Center for Future Foods, Jiangnan University, Wuxi, Jiangsu, China
| | - Patrick A. Gibney
- Department of Food Science, Cornell University, Ithaca, New York, United States
| |
Collapse
|
5
|
Kim H, Moore CM, Mestre-Fos S, Hanna DA, Williams LD, Reddi AR, Torres MP. Depletion assisted hemin affinity (DAsHA) proteomics reveals an expanded landscape of heme-binding proteins in the human proteome. Metallomics 2023; 15:6994529. [PMID: 36669767 PMCID: PMC10022665 DOI: 10.1093/mtomcs/mfad004] [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: 08/26/2022] [Accepted: 01/19/2023] [Indexed: 01/22/2023]
Abstract
Heme b (iron protoporphyrin IX) plays important roles in biology as a metallocofactor and signaling molecule. However, the targets of heme signaling and the network of proteins that mediate the exchange of heme from sites of synthesis or uptake to heme dependent or regulated proteins are poorly understood. Herein, we describe a quantitative mass spectrometry (MS)-based chemoproteomics strategy to identify exchange labile hemoproteins in human embryonic kidney HEK293 cells that may be relevant to heme signaling and trafficking. The strategy involves depleting endogenous heme with the heme biosynthetic inhibitor succinylacetone (SA), leaving putative heme-binding proteins in their apo-state, followed by the capture of those proteins using hemin-agarose resin, and finally elution and identification by MS. By identifying only those proteins that interact with high specificity to hemin-agarose relative to control beaded agarose in an SA-dependent manner, we have expanded the number of proteins and ontologies that may be involved in binding and buffering labile heme or are targets of heme signaling. Notably, these include proteins involved in chromatin remodeling, DNA damage response, RNA splicing, cytoskeletal organization, and vesicular trafficking, many of which have been associated with heme through complementary studies published recently. Taken together, these results provide support for the emerging role of heme in an expanded set of cellular processes from genome integrity to protein trafficking and beyond.
Collapse
Affiliation(s)
- Hyojung Kim
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Courtney M Moore
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Santi Mestre-Fos
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - David A Hanna
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Loren Dean Williams
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Amit R Reddi
- Correspondence: Amit R. Reddi, School of Chemistry and Biochemistry, Georgia Institute of Technology, 950 Atlantic Dr. Atlanta, GA 30033. E-mail:
| | - Matthew P Torres
- Correspondence: Matthew P. Torres, School of Biological Sciences, Georgia Institute of Technology, 950 Atlantic Dr. Atlanta, GA 30033. E-mail:
| |
Collapse
|
6
|
Jordá T, Barba-Aliaga M, Rozès N, Alepuz P, Martínez-Pastor MT, Puig S. Transcriptional regulation of ergosterol biosynthesis genes in response to iron deficiency. Environ Microbiol 2022; 24:5248-5260. [PMID: 36382795 DOI: 10.1111/1462-2920.16157] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 08/01/2022] [Indexed: 01/07/2023]
Abstract
Iron participates as an essential cofactor in the biosynthesis of critical cellular components, including DNA, proteins and lipids. The ergosterol biosynthetic pathway, which is an important target of antifungal treatments, depends on iron in four enzymatic steps. Our results in the model yeast Saccharomyces cerevisiae show that the expression of ergosterol biosynthesis (ERG) genes is tightly modulated by iron availability probably through the iron-dependent variation of sterol and heme levels. Whereas the transcription factors Upc2 and Ecm22 are responsible for the activation of ERG genes upon iron deficiency, the heme-dependent factor Hap1 triggers their Tup1-mediated transcriptional repression. The combined regulation by both activating and repressing regulatory factors allows for the fine-tuning of ERG transcript levels along the progress of iron deficiency, avoiding the accumulation of toxic sterol intermediates and enabling efficient adaptation to rapidly changing conditions. The lack of these regulatory factors leads to changes in the yeast sterol profile upon iron-deficient conditions. Both environmental iron availability and specific regulatory factors should be considered in ergosterol antifungal treatments.
Collapse
Affiliation(s)
- Tania Jordá
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain
| | - Marina Barba-Aliaga
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, Burjassot, Valencia, Spain.,Departamento de Bioquímica y Biología Molecular, Universitat de València, Burjassot, Valencia, Spain
| | - Nicolas Rozès
- Departament de Bioquímica i Biotecnologia, Facultat d'Enologia, Universitat Rovira i Virgili, Tarragona, Spain
| | - Paula Alepuz
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, Burjassot, Valencia, Spain.,Departamento de Bioquímica y Biología Molecular, Universitat de València, Burjassot, Valencia, Spain
| | | | - Sergi Puig
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain
| |
Collapse
|
7
|
Barba‐Aliaga M, Alepuz P. The activator/repressor Hap1 binds to the yeast eIF5A‐encoding gene
TIF51A
to adapt its expression to the mitochondrial functional status. FEBS Lett 2022; 596:1809-1826. [DOI: 10.1002/1873-3468.14366] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/12/2022] [Accepted: 04/22/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Marina Barba‐Aliaga
- Instituto de Biotecnología y Biomedicina (Biotecmed) Universitat de València 46100 València Spain
- Departamento de Bioquímica y Biología Molecular Facultad de Ciencias Biológicas Universitat de València 46100 València Spain
| | - Paula Alepuz
- Instituto de Biotecnología y Biomedicina (Biotecmed) Universitat de València 46100 València Spain
- Departamento de Bioquímica y Biología Molecular Facultad de Ciencias Biológicas Universitat de València 46100 València Spain
| |
Collapse
|
8
|
Barba-Aliaga M, Alepuz P. Role of eIF5A in Mitochondrial Function. Int J Mol Sci 2022; 23:1284. [PMID: 35163207 PMCID: PMC8835957 DOI: 10.3390/ijms23031284] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/19/2022] [Accepted: 01/21/2022] [Indexed: 12/17/2022] Open
Abstract
The eukaryotic translation initiation factor 5A (eIF5A) is an evolutionarily conserved protein that binds ribosomes to facilitate the translation of peptide motifs with consecutive prolines or combinations of prolines with glycine and charged amino acids. It has also been linked to other molecular functions and cellular processes, such as nuclear mRNA export and mRNA decay, proliferation, differentiation, autophagy, and apoptosis. The growing interest in eIF5A relates to its association with the pathogenesis of several diseases, including cancer, viral infection, and diabetes. It has also been proposed as an anti-aging factor: its levels decay in aged cells, whereas increasing levels of active eIF5A result in the rejuvenation of the immune and vascular systems and improved brain cognition. Recent data have linked the role of eIF5A in some pathologies with its function in maintaining healthy mitochondria. The eukaryotic translation initiation factor 5A is upregulated under respiratory metabolism and its deficiency reduces oxygen consumption, ATP production, and the levels of several mitochondrial metabolic enzymes, as well as altering mitochondria dynamics. However, although all the accumulated data strongly link eIF5A to mitochondrial function, the precise molecular role and mechanisms involved are still unknown. In this review, we discuss the findings linking eIF5A and mitochondria, speculate about its role in regulating mitochondrial homeostasis, and highlight its potential as a target in diseases related to energy metabolism.
Collapse
Affiliation(s)
- Marina Barba-Aliaga
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, 46100 València, Spain
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, 46100 València, Spain
| | - Paula Alepuz
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, 46100 València, Spain
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, 46100 València, Spain
| |
Collapse
|
9
|
Blocking mitophagy does not significantly improve fuel ethanol production in bioethanol yeast Saccharomyces cerevisiae. Appl Environ Microbiol 2022; 88:e0206821. [PMID: 35044803 DOI: 10.1128/aem.02068-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ethanolic fermentation is frequently performed under conditions of low nitrogen. In Saccharomyces cerevisiae, nitrogen limitation induces macroautophagy, including the selective removal of mitochondria, also called mitophagy. Shiroma and co-workers (2014) showed that blocking mitophagy by deletion of the mitophagy specific gene ATG32 increased the fermentation performance during the brewing of Ginjo sake. In this study, we tested if a similar strategy could enhance alcoholic fermentation in the context of fuel ethanol production from sugarcane in Brazilian biorefineries. Conditions that mimic the industrial fermentation process indeed induce Atg32-dependent mitophagy in cells of S. cerevisiae PE-2, a strain frequently used in the industry. However, after blocking mitophagy, no significant differences in CO2 production, final ethanol titres or cell viability were observed after five rounds of ethanol fermentation, cell recycling and acid treatment, as commonly performed in sugarcane biorefineries. To test if S. cerevisiae's strain background influences this outcome, cultivations were carried out in a synthetic medium with strains PE-2, Ethanol Red (industrial) and BY (laboratory), with and without a functional ATG32 gene, under oxic and oxygen restricted conditions. Despite the clear differences in sugar consumption, cell viability and ethanol titres, among the three strains, we could not observe any significant improvement in fermentation performance related to the blocking of mitophagy. We conclude with caution that results obtained with Ginjo sake yeast is an exception and cannot be extrapolated to other yeast strains and that more research is needed to ascertain the role of autophagic processes during fermentation. Importance Bioethanol is the largest (per volume) ever biobased bulk chemical produced globally. The fermentation process is very well established, and industries regularly attain nearly 85% of maximum theoretical yields. However, because of the volume of fuel produced, even a small improvement will have huge economic benefits. To this end, besides already implemented process improvements, various free energy conservation strategies have been successfully exploited at least in laboratory strains to increase ethanol yields and decrease by-product formation. Cellular housekeeping processes have been an almost unexplored territory in strain improvement. Shiroma and co-workers previously reported that blocking mitophagy by deletion of the mitophagy receptor gene ATG32 in Saccharomyces cerevisiae led to a 2.1% increase in final ethanol titres during Japanese sake fermentation. We found in two commercially used bioethanol strains (PE-2 and Ethanol Red) that ATG32 deficiency does not lead to a significant improvement in cell viability or ethanol levels during fermentation with molasses or in a synthetic complete medium. More research is required to ascertain the role of autophagic processes during fermentation conditions.
Collapse
|
10
|
Robinson JR, Isikhuemhen OS, Anike FN. Fungal-Metal Interactions: A Review of Toxicity and Homeostasis. J Fungi (Basel) 2021; 7:225. [PMID: 33803838 PMCID: PMC8003315 DOI: 10.3390/jof7030225] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 03/15/2021] [Accepted: 03/17/2021] [Indexed: 12/18/2022] Open
Abstract
Metal nanoparticles used as antifungals have increased the occurrence of fungal-metal interactions. However, there is a lack of knowledge about how these interactions cause genomic and physiological changes, which can produce fungal superbugs. Despite interest in these interactions, there is limited understanding of resistance mechanisms in most fungi studied until now. We highlight the current knowledge of fungal homeostasis of zinc, copper, iron, manganese, and silver to comprehensively examine associated mechanisms of resistance. Such mechanisms have been widely studied in Saccharomyces cerevisiae, but limited reports exist in filamentous fungi, though they are frequently the subject of nanoparticle biosynthesis and targets of antifungal metals. In most cases, microarray analyses uncovered resistance mechanisms as a response to metal exposure. In yeast, metal resistance is mainly due to the down-regulation of metal ion importers, utilization of metallothionein and metallothionein-like structures, and ion sequestration to the vacuole. In contrast, metal resistance in filamentous fungi heavily relies upon cellular ion export. However, there are instances of resistance that utilized vacuole sequestration, ion metallothionein, and chelator binding, deleting a metal ion importer, and ion storage in hyphal cell walls. In general, resistance to zinc, copper, iron, and manganese is extensively reported in yeast and partially known in filamentous fungi; and silver resistance lacks comprehensive understanding in both.
Collapse
Affiliation(s)
| | - Omoanghe S. Isikhuemhen
- Department of Natural Resources and Environmental Design, North Carolina Agricultural and Technical State University, 1601 East Market Street, Greensboro, NC 27411, USA; (J.R.R.); (F.N.A.)
| | | |
Collapse
|
11
|
Collins JH, Keating KW, Jones TR, Balaji S, Marsan CB, Çomo M, Newlon ZJ, Mitchell T, Bartley B, Adler A, Roehner N, Young EM. Engineered yeast genomes accurately assembled from pure and mixed samples. Nat Commun 2021; 12:1485. [PMID: 33674578 PMCID: PMC7935868 DOI: 10.1038/s41467-021-21656-9] [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: 02/21/2020] [Accepted: 02/04/2021] [Indexed: 01/31/2023] Open
Abstract
Yeast whole genome sequencing (WGS) lacks end-to-end workflows that identify genetic engineering. Here we present Prymetime, a tool that assembles yeast plasmids and chromosomes and annotates genetic engineering sequences. It is a hybrid workflow-it uses short and long reads as inputs to perform separate linear and circular assembly steps. This structure is necessary to accurately resolve genetic engineering sequences in plasmids and the genome. We show this by assembling diverse engineered yeasts, in some cases revealing unintended deletions and integrations. Furthermore, the resulting whole genomes are high quality, although the underlying assembly software does not consistently resolve highly repetitive genome features. Finally, we assemble plasmids and genome integrations from metagenomic sequencing, even with 1 engineered cell in 1000. This work is a blueprint for building WGS workflows and establishes WGS-based identification of yeast genetic engineering.
Collapse
Affiliation(s)
- Joseph H Collins
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Kevin W Keating
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Trent R Jones
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Shravani Balaji
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Celeste B Marsan
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Marina Çomo
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Zachary J Newlon
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Tom Mitchell
- Synthetic Biology, Raytheon BBN Technologies, Cambridge, MA, USA
| | - Bryan Bartley
- Synthetic Biology, Raytheon BBN Technologies, Cambridge, MA, USA
| | - Aaron Adler
- Synthetic Biology, Raytheon BBN Technologies, Cambridge, MA, USA
| | - Nicholas Roehner
- Synthetic Biology, Raytheon BBN Technologies, Cambridge, MA, USA
| | - Eric M Young
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA.
| |
Collapse
|
12
|
Barba-Aliaga M, Villarroel-Vicente C, Stanciu A, Corman A, Martínez-Pastor MT, Alepuz P. Yeast Translation Elongation Factor eIF5A Expression Is Regulated by Nutrient Availability through Different Signalling Pathways. Int J Mol Sci 2020; 22:E219. [PMID: 33379337 PMCID: PMC7794953 DOI: 10.3390/ijms22010219] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/17/2020] [Accepted: 12/24/2020] [Indexed: 12/15/2022] Open
Abstract
Translation elongation factor eIF5A binds to ribosomes to promote peptide bonds between problematic amino acids for the reaction like prolines. eIF5A is highly conserved and essential in eukaryotes, which usually contain two similar but differentially expressed paralogue genes. The human eIF5A-1 isoform is abundant and implicated in some cancer types; the eIF5A-2 isoform is absent in most cells but becomes overexpressed in many metastatic cancers. Several reports have connected eIF5A and mitochondria because it co-purifies with the organelle or its inhibition reduces respiration and mitochondrial enzyme levels. However, the mechanisms of eIF5A mitochondrial function, and whether eIF5A expression is regulated by the mitochondrial metabolism, are unknown. We analysed the expression of yeast eIF5A isoforms Tif51A and Tif51B under several metabolic conditions and in mutants. The depletion of Tif51A, but not Tif51B, compromised yeast growth under respiration and reduced oxygen consumption. Tif51A expression followed dual positive regulation: by high glucose through TORC1 signalling, like other translation factors, to promote growth and by low glucose or non-fermentative carbon sources through Snf1 and heme-dependent transcription factor Hap1 to promote respiration. Upon iron depletion, Tif51A was down-regulated and Tif51B up-regulated. Both were Hap1-dependent. Our results demonstrate eIF5A expression regulation by cellular metabolic status.
Collapse
Affiliation(s)
- Marina Barba-Aliaga
- Instituto Biotecmed, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain; (M.B.-A.); (C.V.-V.); (A.S.); (A.C.)
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain;
| | - Carlos Villarroel-Vicente
- Instituto Biotecmed, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain; (M.B.-A.); (C.V.-V.); (A.S.); (A.C.)
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain;
| | - Alice Stanciu
- Instituto Biotecmed, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain; (M.B.-A.); (C.V.-V.); (A.S.); (A.C.)
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain;
| | - Alba Corman
- Instituto Biotecmed, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain; (M.B.-A.); (C.V.-V.); (A.S.); (A.C.)
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain;
| | - María Teresa Martínez-Pastor
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain;
| | - Paula Alepuz
- Instituto Biotecmed, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain; (M.B.-A.); (C.V.-V.); (A.S.); (A.C.)
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, C/Dr. Moliner 50, E46100 Burjassot, Spain;
| |
Collapse
|
13
|
Buechel ER, Pinkett HW. Transcription factors and ABC transporters: from pleiotropic drug resistance to cellular signaling in yeast. FEBS Lett 2020; 594:3943-3964. [PMID: 33089887 DOI: 10.1002/1873-3468.13964] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/07/2020] [Accepted: 10/15/2020] [Indexed: 12/24/2022]
Abstract
Budding yeast Saccharomyces cerevisiae survives in microenvironments utilizing networks of regulators and ATP-binding cassette (ABC) transporters to circumvent toxins and a variety of drugs. Our understanding of transcriptional regulation of ABC transporters in yeast is mainly derived from the study of multidrug resistance protein networks. Over the past two decades, this research has not only expanded the role of transcriptional regulators in pleiotropic drug resistance (PDR) but evolved to include the role that regulators play in cellular signaling and environmental adaptation. Inspection of the gene networks of the transcriptional regulators and characterization of the ABC transporters has clarified that they also contribute to environmental adaptation by controlling plasma membrane composition, toxic-metal sequestration, and oxidative stress adaptation. Additionally, ABC transporters and their regulators appear to be involved in cellular signaling for adaptation of S. cerevisiae populations to nutrient availability. In this review, we summarize the current understanding of the S. cerevisiae transcriptional regulatory networks and highlight recent work in other notable fungal organisms, underlining the expansion of the study of these gene networks across the kingdom fungi.
Collapse
Affiliation(s)
- Evan R Buechel
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA
| | - Heather W Pinkett
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA
| |
Collapse
|
14
|
Shekhawat K, Bauer FF, Setati ME. The transcriptomic response of a wine strain of Lachancea thermotolerans to oxygen deprivation. FEMS Yeast Res 2020; 20:5909970. [PMID: 32960268 DOI: 10.1093/femsyr/foaa054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 09/20/2020] [Indexed: 11/14/2022] Open
Abstract
The yeast Lachancea thermotolerans is of significant biotechnological interest, and selected strains of this species have become commonly used starter cultures in wine fermentation. However, the impact of this species on wine is frequently limited by the rapid dominance of Saccharomyces cerevisiae strains which are better adapted to wine alcoholic fermentation conditions. Previous studies have shown that the major limiting factor for L. thermotolerans competitive performance in the wine ecosystem is oxygen availability, and not ethanol levels as had been previously suggested. Here we investigated the transcriptional response of L. thermotolerans to anaerobiosis in wine fermentation conditions. The data show that L. thermotolerans broadly redirects gene expression towards genes involved in central carbon metabolism, lipid metabolism, remodeling of the cell wall as well as autophagy. Furthermore, the induction of genes that are likely involved in the generation of lactate indicates a redirection of metabolic flux towards this metabolite. The data provide the first insight into the oxygen-dependent response of L. thermotolerans and suggest potential genetic targets to improve lactate production and/or anaerobic fermentation performance of this yeast.
Collapse
Affiliation(s)
- Kirti Shekhawat
- South African Grape and Wine Research Institute, Department of Viticulture and Oenology, Stellenbosch University, P/Bag X1 Matieland, 7600, Western Cape, South Africa
| | - Florian F Bauer
- South African Grape and Wine Research Institute, Department of Viticulture and Oenology, Stellenbosch University, P/Bag X1 Matieland, 7600, Western Cape, South Africa
| | - Mathabatha E Setati
- South African Grape and Wine Research Institute, Department of Viticulture and Oenology, Stellenbosch University, P/Bag X1 Matieland, 7600, Western Cape, South Africa
| |
Collapse
|
15
|
Keppel M, Hünnefeld M, Filipchyk A, Viets U, Davoudi CF, Krüger A, Mack C, Pfeifer E, Polen T, Baumgart M, Bott M, Frunzke J. HrrSA orchestrates a systemic response to heme and determines prioritization of terminal cytochrome oxidase expression. Nucleic Acids Res 2020; 48:6547-6562. [PMID: 32453397 PMCID: PMC7337898 DOI: 10.1093/nar/gkaa415] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 04/26/2020] [Accepted: 05/05/2020] [Indexed: 01/02/2023] Open
Abstract
Heme is a multifaceted molecule. While serving as a prosthetic group for many important proteins, elevated levels are toxic to cells. The complexity of this stimulus has shaped bacterial network evolution. However, only a small number of targets controlled by heme-responsive regulators have been described to date. Here, we performed chromatin affinity purification and sequencing to provide genome-wide insights into in vivo promoter occupancy of HrrA, the response regulator of the heme-regulated two-component system HrrSA of Corynebacterium glutamicum. Time-resolved profiling revealed dynamic binding of HrrA to more than 200 different genomic targets encoding proteins associated with heme biosynthesis, the respiratory chain, oxidative stress response and cell envelope remodeling. By repression of the extracytoplasmic function sigma factor sigC, which activates the cydABCD operon, HrrA prioritizes the expression of genes encoding the cytochrome bc1-aa3 supercomplex. This is also reflected by a significantly decreased activity of the cytochrome aa3 oxidase in the ΔhrrA mutant. Furthermore, our data reveal that HrrA also integrates the response to heme-induced oxidative stress by activating katA encoding the catalase. These data provide detailed insights in the systemic strategy that bacteria have evolved to respond to the versatile signaling molecule heme.
Collapse
Affiliation(s)
- Marc Keppel
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Max Hünnefeld
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Andrei Filipchyk
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Ulrike Viets
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Cedric-Farhad Davoudi
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Aileen Krüger
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Christina Mack
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Eugen Pfeifer
- Microbial Evolutionary Genomics, Institute Pasteur, 75015 Paris, France
| | - Tino Polen
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Meike Baumgart
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Michael Bott
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Julia Frunzke
- Institute of Bio- und Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| |
Collapse
|
16
|
Regulation of Ergosterol Biosynthesis in Saccharomyces cerevisiae. Genes (Basel) 2020; 11:genes11070795. [PMID: 32679672 PMCID: PMC7397035 DOI: 10.3390/genes11070795] [Citation(s) in RCA: 175] [Impact Index Per Article: 43.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/06/2020] [Accepted: 07/13/2020] [Indexed: 12/14/2022] Open
Abstract
Ergosterol is an essential component of fungal cell membranes that determines the fluidity, permeability and activity of membrane-associated proteins. Ergosterol biosynthesis is a complex and highly energy-consuming pathway that involves the participation of many enzymes. Deficiencies in sterol biosynthesis cause pleiotropic defects that limit cellular proliferation and adaptation to stress. Thereby, fungal ergosterol levels are tightly controlled by the bioavailability of particular metabolites (e.g., sterols, oxygen and iron) and environmental conditions. The regulation of ergosterol synthesis is achieved by overlapping mechanisms that include transcriptional expression, feedback inhibition of enzymes and changes in their subcellular localization. In the budding yeast Saccharomyces cerevisiae, the sterol regulatory element (SRE)-binding proteins Upc2 and Ecm22, the heme-binding protein Hap1 and the repressor factors Rox1 and Mot3 coordinate ergosterol biosynthesis (ERG) gene expression. Here, we summarize the sterol biosynthesis, transport and detoxification systems of S. cerevisiae, as well as its adaptive response to sterol depletion, low oxygen, hyperosmotic stress and iron deficiency. Because of the large number of ERG genes and the crosstalk between different environmental signals and pathways, many aspects of ergosterol regulation are still unknown. The study of sterol metabolism and its regulation is highly relevant due to its wide applications in antifungal treatments, as well as in food and pharmaceutical industries.
Collapse
|
17
|
Bhondeley M, Liu Z. Mitochondrial Biogenesis Is Positively Regulated by Casein Kinase I Hrr25 Through Phosphorylation of Puf3 in Saccharomyces cerevisiae. Genetics 2020; 215:463-482. [PMID: 32317286 PMCID: PMC7268985 DOI: 10.1534/genetics.120.303191] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 04/20/2020] [Indexed: 11/18/2022] Open
Abstract
Mitochondrial biogenesis requires coordinated expression of genes encoding mitochondrial proteins, which in Saccharomyces cerevisiae is achieved in part via post-transcriptional control by the Pumilio RNA-binding domain protein Puf3 Puf3 binds to the 3'-UTR of many messenger RNAs (mRNAs) that encode mitochondrial proteins, regulating their turnover, translation, and/or mitochondrial targeting. Puf3 hyperphosphorylation correlates with increased mitochondrial biogenesis; however, the kinase responsible for Puf3 phosphorylation is unclear. Here, we show that the casein kinase I protein Hrr25 negatively regulates Puf3 by mediating its phosphorylation. An hrr25 mutation results in reduced phosphorylation of Puf3 in vivo and a puf3 deletion mutation reverses growth defects of hrr25 mutant cells grown on medium with a nonfermentable carbon source. We show that Hrr25 directly phosphorylates Puf3, and that the interaction between Puf3 and Hrr25 is mediated through the N-terminal domain of Puf3 and the kinase domain of Hrr25 We further found that an hrr25 mutation reduces GFP expression from GFP reporter constructs carrying the 3'-UTR of Puf3 targets. Downregulation of GFP expression due to an hrr25 mutation can be reversed either by puf3Δ or by mutations to the Puf3-binding sites in the 3'-UTR of the GFP reporter constructs. Together, our data indicate that Hrr25 is a positive regulator of mitochondrial biogenesis by phosphorylating Puf3 and inhibiting its function in downregulating target mRNAs encoding mitochondrial proteins.
Collapse
Affiliation(s)
- Manika Bhondeley
- Department of Biological Sciences, University of New Orleans, Louisiana 70148
| | - Zhengchang Liu
- Department of Biological Sciences, University of New Orleans, Louisiana 70148
| |
Collapse
|
18
|
Gibney PA, Chen A, Schieler A, Chen JC, Xu Y, Hendrickson DG, McIsaac RS, Rabinowitz JD, Botstein D. A tps1Δ persister-like state in Saccharomyces cerevisiae is regulated by MKT1. PLoS One 2020; 15:e0233779. [PMID: 32470059 PMCID: PMC7259636 DOI: 10.1371/journal.pone.0233779] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/12/2020] [Indexed: 11/18/2022] Open
Abstract
Trehalose metabolism in yeast has been linked to a variety of phenotypes, including heat resistance, desiccation tolerance, carbon-source utilization, and sporulation. The relationships among the several phenotypes of mutants unable to synthesize trehalose are not understood, even though the pathway is highly conserved. One of these phenotypes is that tps1Δ strains cannot reportedly grow on media containing glucose or fructose, even when another carbon source they can use (e.g. galactose) is present. Here we corroborate the recent observation that a small fraction of yeast tps1Δ cells do grow on glucose, unlike the majority of the population. This is not due to a genetic alteration, but instead resembles the persister phenotype documented in many microorganisms and cancer cells undergoing lethal stress. We extend these observations to show that this phenomenon is glucose-specific, as it does not occur on another highly fermented carbon source, fructose. We further demonstrate that this phenomenon appears to be related to mitochondrial complex III function, but unrelated to inorganic phosphate levels in the cell, as had previously been suggested. Finally, we found that this phenomenon is specific to S288C-derived strains, and is the consequence of a variant in the MKT1 gene.
Collapse
Affiliation(s)
- Patrick A. Gibney
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
- Calico Life Sciences LLC, South San Francisco, California, United States of America
- Department of Food Science, Cornell University, Ithaca, New York, United States of America
| | - Anqi Chen
- Department of Food Science, Cornell University, Ithaca, New York, United States of America
| | - Ariel Schieler
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Jonathan C. Chen
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
- Department of Chemistry, Princeton University, Princeton, New Jersey, United States of America
| | - Yifan Xu
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
- Department of Chemistry, Princeton University, Princeton, New Jersey, United States of America
| | - David G. Hendrickson
- Calico Life Sciences LLC, South San Francisco, California, United States of America
| | - R. Scott McIsaac
- Calico Life Sciences LLC, South San Francisco, California, United States of America
| | - Joshua D. Rabinowitz
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
- Department of Chemistry, Princeton University, Princeton, New Jersey, United States of America
| | - David Botstein
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
- Calico Life Sciences LLC, South San Francisco, California, United States of America
| |
Collapse
|
19
|
Sinha A, Israeli R, Cirigliano A, Gihaz S, Trabelcy B, Braus GH, Gerchman Y, Fishman A, Negri R, Rinaldi T, Pick E. The COP9 signalosome mediates the Spt23 regulated fatty acid desaturation and ergosterol biosynthesis. FASEB J 2020; 34:4870-4889. [PMID: 32077151 DOI: 10.1096/fj.201902487r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 01/02/2020] [Accepted: 01/14/2020] [Indexed: 02/06/2023]
Abstract
The COP9 signalosome (CSN) is a conserved eukaryotic complex, essential for vitality in all multicellular organisms and critical for the turnover of key cellular proteins through catalytic and non-catalytic activities. Saccharomyces cerevisiae is a powerful model organism for studying fundamental aspects of the CSN complex, since it includes a conserved enzymatic core but lacks non-catalytic activities, probably explaining its non-essentiality for life. A previous transcriptomic analysis of an S. cerevisiae strain deleted in the CSN5/RRI1 gene, encoding to the CSN catalytic subunit, revealed a downregulation of genes involved in lipid metabolism. We now show that the S. cerevisiae CSN holocomplex is essential for cellular lipid homeostasis. Defects in CSN assembly or activity lead to decreased quantities of ergosterol and unsaturated fatty acids (UFA); vacuole defects; diminished lipid droplets (LDs) size; and to accumulation of endoplasmic reticulum (ER) stress. The molecular mechanism behind these findings depends on CSN involvement in upregulating mRNA expression of SPT23. Spt23 is a novel activator of lipid desaturation and ergosterol biosynthesis. Our data reveal for the first time a functional link between the CSN holocomplex and Spt23. Moreover, CSN-dependent upregulation of SPT23 transcription is necessary for the fine-tuning of lipid homeostasis and for cellular health.
Collapse
Affiliation(s)
- Abhishek Sinha
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel
| | - Ran Israeli
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel
| | - Angela Cirigliano
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | - Shalev Gihaz
- Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Beny Trabelcy
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Goettingen Center for Molecular Biosciences (GZMB), University of Goettingen, Goettingen, Germany
| | - Yoram Gerchman
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel
| | - Ayelet Fishman
- Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Rodolfo Negri
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | - Teresa Rinaldi
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | - Elah Pick
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel
| |
Collapse
|
20
|
Geller SH, Antwi EB, Di Ventura B, McClean MN. Optogenetic Repressors of Gene Expression in Yeasts Using Light-Controlled Nuclear Localization. Cell Mol Bioeng 2019; 12:511-528. [PMID: 31719930 PMCID: PMC6816687 DOI: 10.1007/s12195-019-00598-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 09/03/2019] [Indexed: 01/30/2023] Open
Abstract
INTRODUCTION Controlling gene expression is a fundamental goal of basic and synthetic biology because it allows insight into cellular function and control of cellular activity. We explored the possibility of generating an optogenetic repressor of gene expression in the model organism Saccharomyces cerevisiae by using light to control the nuclear localization of nuclease-dead Cas9, dCas9. METHODS The dCas9 protein acts as a repressor for a gene of interest when localized to the nucleus in the presence of an appropriate guide RNA (sgRNA). We engineered dCas9, the mammalian transcriptional repressor Mxi1, and an optogenetic tool to control nuclear localization (LINuS) as parts in an existing yeast optogenetic toolkit. This allowed expression cassettes containing novel dCas9 repressor configurations and guide RNAs to be rapidly constructed and integrated into yeast. RESULTS Our library of repressors displays a range of basal repression without the need for inducers or promoter modification. Populations of cells containing these repressors can be combined to generate a heterogeneous population of yeast with a 100-fold expression range. We find that repression can be dialed modestly in a light dose- and intensity-dependent manner. We used this library to repress expression of the lanosterol 14-alpha-demethylase Erg11, generating yeast with a range of sensitivity to the important antifungal drug fluconazole. CONCLUSIONS This toolkit will be useful for spatiotemporal perturbation of gene expression in Saccharomyces cerevisiae. Additionally, we believe that the simplicity of our scheme will allow these repressors to be easily modified to control gene expression in medically relevant fungi, such as pathogenic yeasts.
Collapse
Affiliation(s)
- Stephanie H. Geller
- Department of Biomedical Engineering, University of Wisconsin-Madison, 1550 Engineering Drive, Madison, WI 53706 USA
- Cellular and Molecular Biology Graduate Program, University of Wisconsin-Madison, 1525 Linden Dr., Madison, WI 53706 USA
| | - Enoch B. Antwi
- Institute of Biology II, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany
- Heidelberg Biosciences International Graduate School (HBIGS), 69120 Heidelberg, Germany
| | - Barbara Di Ventura
- Institute of Biology II, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany
| | - Megan N. McClean
- Department of Biomedical Engineering, University of Wisconsin-Madison, 1550 Engineering Drive, Madison, WI 53706 USA
| |
Collapse
|
21
|
Transcriptomic Response of Saccharomyces cerevisiae during Fermentation under Oleic Acid and Ergosterol Depletion. FERMENTATION-BASEL 2019. [DOI: 10.3390/fermentation5030057] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Under anaerobic/hypoxic conditions, Saccharomyces cerevisiae relies on external lipid supplements to modulate membrane lipid fraction in response to different stresses. Here, transcriptomic responses of two S. cerevisiae wine strains were evaluated during hypoxic fermentation of a synthetic must with/without ergosterol and oleic acid supplementation. In the absence of lipids, the two strains, namely EC1118 and M25, showed different behaviour, with M25 significantly decreasing its fermentation rate from the 72 h after inoculum. At this time point, the whole genome transcriptomic analysis revealed common and strain-specific responses to the lack of lipid supplementation. Common responses included the upregulation of the genes involved in ergosterol biosynthesis, as well as the seripauperin and the heat shock protein multigene families. In addition, the upregulation of the aerobic isoforms of genes involved in mitochondrial electron transport is compatible with the previously observed accumulation of reactive oxygen species in the two strains during growth in absence of lipids. Considering the strain-specific responses, M25 downregulated the transcription of genes involved in glucose transport, methionine biosynthesis and of those encoding mannoproteins required for adaptation to low temperatures and hypoxia. The identification of these pathways, which are presumably involved in yeast resistance to stresses, will assist industrial strain selection.
Collapse
|
22
|
Minor Isozymes Tailor Yeast Metabolism to Carbon Availability. mSystems 2019; 4:mSystems00170-18. [PMID: 30834327 PMCID: PMC6392091 DOI: 10.1128/msystems.00170-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 01/21/2019] [Indexed: 11/23/2022] Open
Abstract
Gene duplication is one of the main evolutionary paths to new protein function. Typically, duplicated genes either accumulate mutations and degrade into pseudogenes or are retained and diverge in function. Some duplicated genes, however, show long-term persistence without apparently acquiring new function. An important class of isozymes consists of those that catalyze the same reaction in the same compartment, where knockout of one isozyme causes no known functional defect. Here we present an approach to assigning specific functional roles to seemingly redundant isozymes. First, gene expression data are analyzed computationally to identify conditions under which isozyme expression diverges. Then, knockouts are compared under those conditions. This approach revealed that the expression of many yeast isozymes diverges in response to carbon availability and that carbon source manipulations can induce fitness phenotypes for seemingly redundant isozymes. A driver of these fitness phenotypes is differential allosteric enzyme regulation, indicating isozyme divergence to achieve more-optimal control of metabolism. Isozymes are enzymes that differ in sequence but catalyze the same chemical reactions. Despite their apparent redundancy, isozymes are often retained over evolutionary time, suggesting that they contribute to fitness. We developed an unsupervised computational method for identifying environmental conditions under which isozymes are likely to make fitness contributions. This method analyzes published gene expression data to find specific experimental perturbations that induce differential isozyme expression. In yeast, we found that isozymes are strongly enriched in the pathways of central carbon metabolism and that many isozyme pairs show anticorrelated expression during the respirofermentative shift. Building on these observations, we assigned function to two minor central carbon isozymes, aconitase 2 (ACO2) and pyruvate kinase 2 (PYK2). ACO2 is expressed during fermentation and proves advantageous when glucose is limiting. PYK2 is expressed during respiration and proves advantageous for growth on three-carbon substrates. PYK2’s deletion can be rescued by expressing the major pyruvate kinase only if that enzyme carries mutations mirroring PYK2’s allosteric regulation. Thus, central carbon isozymes help to optimize allosteric metabolic regulation under a broad range of potential nutrient conditions while requiring only a small number of transcriptional states. IMPORTANCE Gene duplication is one of the main evolutionary paths to new protein function. Typically, duplicated genes either accumulate mutations and degrade into pseudogenes or are retained and diverge in function. Some duplicated genes, however, show long-term persistence without apparently acquiring new function. An important class of isozymes consists of those that catalyze the same reaction in the same compartment, where knockout of one isozyme causes no known functional defect. Here we present an approach to assigning specific functional roles to seemingly redundant isozymes. First, gene expression data are analyzed computationally to identify conditions under which isozyme expression diverges. Then, knockouts are compared under those conditions. This approach revealed that the expression of many yeast isozymes diverges in response to carbon availability and that carbon source manipulations can induce fitness phenotypes for seemingly redundant isozymes. A driver of these fitness phenotypes is differential allosteric enzyme regulation, indicating isozyme divergence to achieve more-optimal control of metabolism.
Collapse
|
23
|
Fleischhacker AS, Carter EL, Ragsdale SW. Redox Regulation of Heme Oxygenase-2 and the Transcription Factor, Rev-Erb, Through Heme Regulatory Motifs. Antioxid Redox Signal 2018; 29:1841-1857. [PMID: 28990415 PMCID: PMC6217750 DOI: 10.1089/ars.2017.7368] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
SIGNIFICANCE Heme binds to and serves as a cofactor for a myriad of proteins that are involved in diverse biological processes. Hemoproteins also exhibit varying modes of heme binding, suggesting that the protein environment contributes to the functional versatility of this prosthetic group. The subject of this review is a subset of hemoproteins that contain at least one heme regulatory motif (HRM), which is a short sequence containing a Cys-Pro core that, in many cases, binds heme with the Cys acting as an axial ligand. Recent Advances: As more details about HRM-containing proteins are uncovered, some underlying commonalities are emerging, including a role in regulating protein stability. Further, the cysteines of some HRMs have been shown to form disulfide bonds. Because the cysteines must be in the reduced, dithiol form to act as a heme axial ligand, heme binds at these sites in a redox-regulated manner, as demonstrated for heme oxygenase-2 (HO2) and Rev-erbβ. CRITICAL ISSUES HRM-containing proteins have wide variations in heme affinity, utilize different axial ligand schemes, and exhibit differences in the ability to act as a redox sensor-all while having a wide variety of biological functions. Here, we highlight HO2 and Rev-erbβ to illustrate the similarities and differences between two hemoproteins that contain HRMs acting as redox sensors. FUTURE DIRECTIONS HRMs acting as redox sensors may be applicable to other HRM-containing proteins as many contain multiple HRMs and/or other cysteine residues, which may become more evident as the functional significance of HRMs is probed in additional proteins.
Collapse
Affiliation(s)
| | - Eric L Carter
- Department of Biological Chemistry, University of Michigan , Ann Arbor, Michigan
| | - Stephen W Ragsdale
- Department of Biological Chemistry, University of Michigan , Ann Arbor, Michigan
| |
Collapse
|
24
|
Hendrickson DG, Soifer I, Wranik BJ, Kim G, Robles M, Gibney PA, McIsaac RS. A new experimental platform facilitates assessment of the transcriptional and chromatin landscapes of aging yeast. eLife 2018; 7:39911. [PMID: 30334737 PMCID: PMC6261268 DOI: 10.7554/elife.39911] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 10/17/2018] [Indexed: 12/22/2022] Open
Abstract
Replicative aging of Saccharomyces cerevisiae is an established model system for eukaryotic cellular aging. A limitation in yeast lifespan studies has been the difficulty of separating old cells from young cells in large quantities. We engineered a new platform, the Miniature-chemostat Aging Device (MAD), that enables purification of aged cells at sufficient quantities for genomic and biochemical characterization of aging yeast populations. Using MAD, we measured DNA accessibility and gene expression changes in aging cells. Our data highlight an intimate connection between aging, growth rate, and stress. Stress-independent genes that change with age are highly enriched for targets of the signal recognition particle (SRP). Combining MAD with an improved ATAC-seq method, we find that increasing proteasome activity reduces rDNA instability usually observed in aging cells and, contrary to published findings, provide evidence that global nucleosome occupancy does not change significantly with age.
Collapse
Affiliation(s)
| | - Ilya Soifer
- Calico Life Sciences LLC, South San Francisco, United States
| | - Bernd J Wranik
- Calico Life Sciences LLC, South San Francisco, United States
| | - Griffin Kim
- Calico Life Sciences LLC, South San Francisco, United States
| | - Michael Robles
- Calico Life Sciences LLC, South San Francisco, United States
| | | | - R Scott McIsaac
- Calico Life Sciences LLC, South San Francisco, United States
| |
Collapse
|
25
|
Tran K, Jethmalani Y, Jaiswal D, Green EM. Set4 is a chromatin-associated protein, promotes survival during oxidative stress, and regulates stress response genes in yeast. J Biol Chem 2018; 293:14429-14443. [PMID: 30082318 PMCID: PMC6139553 DOI: 10.1074/jbc.ra118.003078] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 07/31/2018] [Indexed: 01/14/2023] Open
Abstract
The Set4 protein in the yeast Saccharomyces cerevisiae contains both a PHD finger and a SET domain, a common signature of chromatin-associated proteins, and shares sequence homology with the yeast protein Set3, the fly protein UpSET, and the human protein mixed-lineage leukemia 5 (MLL5). However, the biological role for Set4 and its potential function in chromatin regulation has not been well defined. Here, we analyzed yeast cell phenotypes associated with loss of Set4 or its overexpression, which revealed that Set4 protects against oxidative stress induced by hydrogen peroxide. Gene expression analysis indicated that Set4 promotes the activation of stress response genes in the presence of oxidative insults. Using ChIP analysis and other biochemical assays, we also found that Set4 interacts with chromatin and directly localizes to stress response genes upon oxidative stress. However, recombinant Set4 did not show detectable methyltransferase activity on histones. Our findings also suggest that Set4 abundance in the cell is balanced under normal and stress conditions to promote survival. Overall, these results suggest a model in which Set4 is a stress-responsive, chromatin-associated protein that activates gene expression programs required for cellular protection against oxidative stress. This work advances our understanding of mechanisms that protect cells during oxidative stress and further defines the role of the Set3-Set4 subfamily of SET domain-containing proteins in controlling gene expression in response to adverse environmental conditions.
Collapse
Affiliation(s)
- Khoa Tran
- From the Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland 21250
| | - Yogita Jethmalani
- From the Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland 21250
| | - Deepika Jaiswal
- From the Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland 21250
| | - Erin M Green
- From the Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland 21250
| |
Collapse
|
26
|
Reconstruction of a Global Transcriptional Regulatory Network for Control of Lipid Metabolism in Yeast by Using Chromatin Immunoprecipitation with Lambda Exonuclease Digestion. mSystems 2018; 3:mSystems00215-17. [PMID: 30073202 PMCID: PMC6068829 DOI: 10.1128/msystems.00215-17] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 07/04/2018] [Indexed: 11/20/2022] Open
Abstract
To build transcription regulatory networks, transcription factor binding must be analyzed in cells grown under different conditions because their responses and targets differ depending on environmental conditions. We performed whole-genome analysis of the DNA binding of five Saccharomyces cerevisiae transcription factors involved in lipid metabolism, Ino2, Ino4, Hap1, Oaf1, and Pip2, in response to four different environmental conditions in chemostat cultures, which allowed us to keep the specific growth rate constant. Chromatin immunoprecipitation with lambda exonuclease digestion (ChIP-exo) enabled the detection of binding events at a high resolution. We discovered a large number of unidentified targets and thus expanded functions for each transcription factor (e.g., glutamate biosynthesis as a target of Oaf1 and Pip2). Moreover, condition-dependent binding of transcription factors in response to cell metabolic state (e.g., differential binding of Ino2 between fermentative and respiratory metabolic conditions) was clearly suggested. Combining the new binding data with previously published data from transcription factor deletion studies revealed the high complexity of the transcriptional regulatory network for lipid metabolism in yeast, which involves the combinatorial and complementary regulation by multiple transcription factors. We anticipate that our work will provide insights into transcription factor binding dynamics that will prove useful for the understanding of transcription regulatory networks. IMPORTANCE Transcription factors play a crucial role in the regulation of gene expression and adaptation to different environments. To better understand the underlying roles of these adaptations, we performed experiments that give us high-resolution binding of transcription factors to their targets. We investigated five transcription factors involved in lipid metabolism in yeast, and we discovered multiple novel targets and condition-specific responses that allow us to draw a better regulatory map of the lipid metabolism.
Collapse
|
27
|
Nguyen PV, Hlaváček O, Maršíková J, Váchová L, Palková Z. Cyc8p and Tup1p transcription regulators antagonistically regulate Flo11p expression and complexity of yeast colony biofilms. PLoS Genet 2018; 14:e1007495. [PMID: 29965985 PMCID: PMC6044549 DOI: 10.1371/journal.pgen.1007495] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 07/13/2018] [Accepted: 06/16/2018] [Indexed: 12/26/2022] Open
Abstract
Yeast biofilms are complex multicellular structures, in which the cells are well protected against drugs and other treatments and thus highly resistant to antifungal therapies. Colony biofilms represent an ideal system for studying molecular mechanisms and regulations involved in development and internal organization of biofilm structure as well as those that are involved in fungal domestication. We have identified here antagonistic functional interactions between transcriptional regulators Cyc8p and Tup1p that modulate the life-style of natural S. cerevisiae strains between biofilm and domesticated mode. Herein, strains with different levels of Cyc8p and Tup1p regulators were constructed, analyzed for processes involved in colony biofilm development and used in the identification of modes of regulation of Flo11p, a key adhesin in biofilm formation. Our data show that Tup1p and Cyc8p regulate biofilm formation in the opposite manner, being positive and negative regulators of colony complexity, cell-cell interaction and adhesion to surfaces. Notably, in-depth analysis of regulation of expression of Flo11p adhesin revealed that Cyc8p itself is the key repressor of FLO11 expression, whereas Tup1p counteracts Cyc8p's repressive function and, in addition, counters Flo11p degradation by an extracellular protease. Interestingly, the opposing actions of Tup1p and Cyc8p concern processes crucial to the biofilm mode of yeast multicellularity, whereas other multicellular processes such as cell flocculation are co-repressed by both regulators. This study provides insight into the mechanisms regulating complexity of the biofilm lifestyle of yeast grown on semisolid surfaces.
Collapse
Affiliation(s)
- Phu Van Nguyen
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Otakar Hlaváček
- Institute of Microbiology of the Czech Academy of Sciences, BIOCEV, Vestec, Czech Republic
| | - Jana Maršíková
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Libuše Váchová
- Institute of Microbiology of the Czech Academy of Sciences, BIOCEV, Vestec, Czech Republic
| | - Zdena Palková
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
- * E-mail:
| |
Collapse
|
28
|
Song J, Zhang S, Lu L. Fungal cytochrome P450 protein Cyp51: What we can learn from its evolution, regulons and Cyp51-based azole resistance. FUNGAL BIOL REV 2018. [DOI: 10.1016/j.fbr.2018.05.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
|
29
|
Linkage mapping of yeast cross protection connects gene expression variation to a higher-order organismal trait. PLoS Genet 2018; 14:e1007335. [PMID: 29649251 PMCID: PMC5978988 DOI: 10.1371/journal.pgen.1007335] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 04/24/2018] [Accepted: 03/27/2018] [Indexed: 11/19/2022] Open
Abstract
Gene expression variation is extensive in nature, and is hypothesized to play a major role in shaping phenotypic diversity. However, connecting differences in gene expression across individuals to higher-order organismal traits is not trivial. In many cases, gene expression variation may be evolutionarily neutral, and in other cases expression variation may only affect phenotype under specific conditions. To understand connections between gene expression variation and stress defense phenotypes, we have been leveraging extensive natural variation in the gene expression response to acute ethanol in laboratory and wild Saccharomyces cerevisiae strains. Previous work found that the genetic architecture underlying these expression differences included dozens of “hotspot” loci that affected many transcripts in trans. In the present study, we provide new evidence that one of these expression QTL hotspot loci affects natural variation in one particular stress defense phenotype—ethanol-induced cross protection against severe doses of H2O2. A major causative polymorphism is in the heme-activated transcription factor Hap1p, which we show directly impacts cross protection, but not the basal H2O2 resistance of unstressed cells. This provides further support that distinct cellular mechanisms underlie basal and acquired stress resistance. We also show that Hap1p-dependent cross protection relies on novel regulation of cytosolic catalase T (Ctt1p) during ethanol stress in a wild oak strain. Because ethanol accumulation precedes aerobic respiration and accompanying reactive oxygen species formation, wild strains with the ability to anticipate impending oxidative stress would likely be at an advantage. This study highlights how strategically chosen traits that better correlate with gene expression changes can improve our power to identify novel connections between gene expression variation and higher-order organismal phenotypes. A major goal in genetics is to understand how individuals with different genetic makeups respond to their environment. Understanding these “gene-environment interactions” is important for the development of personalized medicine. For example, gene-environment interactions can explain why some people are more sensitive to certain drugs or are more likely to get certain cancers. While the underlying causes of gene-environment interactions are unclear, one possibility is that differences in gene expression across individuals are responsible. In this study, we examined that possibility using baker’s yeast as a model. We were interested in a phenomenon called acquired stress resistance, where cells exposed to a mild dose of one stress can become resistant to an otherwise lethal dose of severe stress. This response is observed in diverse organisms ranging from bacteria to humans, though the specific mechanisms governing acquisition of higher stress resistance are poorly understood. To understand the differences between yeast strains with and without the ability to acquire further stress resistance, we employed genetic mapping. We found that part of the variation in acquired stress resistance was due to sequence differences in a key regulatory protein, thus providing new insight into how different individuals respond to acute environmental change.
Collapse
|
30
|
Gibney PA, Schieler A, Chen JC, Bacha-Hummel JM, Botstein M, Volpe M, Silverman SJ, Xu Y, Bennett BD, Rabinowitz JD, Botstein D. Common and divergent features of galactose-1-phosphate and fructose-1-phosphate toxicity in yeast. Mol Biol Cell 2018; 29:897-910. [PMID: 29444955 PMCID: PMC5896929 DOI: 10.1091/mbc.e17-11-0666] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Metabolic dysregulation leading to sugar-phosphate accumulation is toxic in organisms ranging from bacteria to humans. By comparing two models of sugar-phosphate toxicity in Saccharomyces cerevisiae, we demonstrate that toxicity occurs, at least in part, through multiple, isomer-specific mechanisms, rather than a single general mechanism.
Collapse
Affiliation(s)
- Patrick A Gibney
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544.,Calico Life Sciences LLC, South San Francisco, CA 94080.,Department of Food Science, Cornell University, Ithaca, NY 14853
| | - Ariel Schieler
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544
| | - Jonathan C Chen
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544.,Department of Chemistry, Princeton University, Princeton, NJ 08544
| | | | - Maxim Botstein
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544
| | - Matthew Volpe
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544
| | - Sanford J Silverman
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544
| | - Yifan Xu
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544.,Department of Chemistry, Princeton University, Princeton, NJ 08544
| | | | - Joshua D Rabinowitz
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544.,Department of Chemistry, Princeton University, Princeton, NJ 08544
| | - David Botstein
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544.,Calico Life Sciences LLC, South San Francisco, CA 94080.,Department of Food Science, Cornell University, Ithaca, NY 14853
| |
Collapse
|
31
|
Na H, Ponomarova O, Giese GE, Walhout AJM. C. elegans MRP-5 Exports Vitamin B12 from Mother to Offspring to Support Embryonic Development. Cell Rep 2018; 22:3126-3133. [PMID: 29562169 PMCID: PMC5896776 DOI: 10.1016/j.celrep.2018.02.100] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 01/05/2018] [Accepted: 02/26/2018] [Indexed: 01/16/2023] Open
Abstract
Vitamin B12 functions as a cofactor for methionine synthase to produce the anabolic methyl donor S-adenosylmethionine (SAM) and for methylmalonyl-CoA mutase to catabolize the short-chain fatty acid propionate. In the nematode Caenorhabditis elegans, maternally supplied vitamin B12 is required for the development of offspring. However, the mechanism for exporting vitamin B12 from the mother to the offspring is not yet known. Here, we use RNAi of more than 200 transporters with a vitamin B12-sensor transgene to identify the ABC transporter MRP-5 as a candidate vitamin B12 exporter. We show that the injection of vitamin B12 into the gonad of mrp-5 deficient mothers rescues embryonic lethality in the offspring. Altogether, our findings identify a maternal mechanism for the transit of an essential vitamin to support the development of the next generation.
Collapse
Affiliation(s)
- Huimin Na
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Olga Ponomarova
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Gabrielle E Giese
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Albertha J M Walhout
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA.
| |
Collapse
|
32
|
A Novel Sterol-Signaling Pathway Governs Azole Antifungal Drug Resistance and Hypoxic Gene Repression in Saccharomyces cerevisiae. Genetics 2017; 208:1037-1055. [PMID: 29263028 DOI: 10.1534/genetics.117.300554] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 12/19/2017] [Indexed: 12/26/2022] Open
Abstract
During antifungal drug treatment and hypoxia, genetic and epigenetic changes occur to maintain sterol homeostasis and cellular function. In this study, we show that SET domain-containing epigenetic factors govern drug efficacy to the medically relevant azole class of antifungal drugs. Upon this discovery, we determined that Set4 is induced when Saccharomyces cerevisiae are treated with azole drugs or grown under hypoxic conditions; two conditions that deplete cellular ergosterol and increase sterol precursors. Interestingly, Set4 induction is controlled by the sterol-sensing transcription factors, Upc2 and Ecm22 To determine the role of Set4 on gene expression under hypoxic conditions, we performed RNA-sequencing analysis and showed that Set4 is required for global changes in gene expression. Specifically, loss of Set4 led to an upregulation of nearly all ergosterol genes, including ERG11 and ERG3, suggesting that Set4 functions in gene repression. Furthermore, mass spectrometry analysis revealed that Set4 interacts with the hypoxic-specific transcriptional repressor, Hap1, where this interaction is necessary for Set4 recruitment to ergosterol gene promoters under hypoxia. Finally, an erg3Δ strain, which produces precursor sterols but lacks ergosterol, expresses Set4 under untreated aerobic conditions. Together, our data suggest that sterol precursors are needed for Set4 induction through an Upc2-mediated mechanism. Overall, this new sterol-signaling pathway governs azole antifungal drug resistance and mediates repression of sterol genes under hypoxic conditions.
Collapse
|
33
|
Efficient protein production by yeast requires global tuning of metabolism. Nat Commun 2017; 8:1131. [PMID: 29070809 PMCID: PMC5656615 DOI: 10.1038/s41467-017-00999-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 08/09/2017] [Indexed: 01/20/2023] Open
Abstract
The biotech industry relies on cell factories for production of pharmaceutical proteins, of which several are among the top-selling medicines. There is, therefore, considerable interest in improving the efficiency of protein production by cell factories. Protein secretion involves numerous intracellular processes with many underlying mechanisms still remaining unclear. Here, we use RNA-seq to study the genome-wide transcriptional response to protein secretion in mutant yeast strains. We find that many cellular processes have to be attuned to support efficient protein secretion. In particular, altered energy metabolism resulting in reduced respiration and increased fermentation, as well as balancing of amino-acid biosynthesis and reduced thiamine biosynthesis seem to be particularly important. We confirm our findings by inverse engineering and physiological characterization and show that by tuning metabolism cells are able to efficiently secrete recombinant proteins. Our findings provide increased understanding of which cellular regulations and pathways are associated with efficient protein secretion. The contribution of metabolic pathways to protein secretion is largely unknown. Here, the authors find conserved metabolic patterns in yeast by examining genome-wide transcriptional responses in high protein secretion mutants and reveal critical factors that can be tuned for efficient protein secretion.
Collapse
|
34
|
Zhang T, Bu P, Zeng J, Vancura A. Increased heme synthesis in yeast induces a metabolic switch from fermentation to respiration even under conditions of glucose repression. J Biol Chem 2017; 292:16942-16954. [PMID: 28830930 DOI: 10.1074/jbc.m117.790923] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 08/18/2017] [Indexed: 01/13/2023] Open
Abstract
Regulation of mitochondrial biogenesis and respiration is a complex process that involves several signaling pathways and transcription factors as well as communication between the nuclear and mitochondrial genomes. Under aerobic conditions, the budding yeast Saccharomyces cerevisiae metabolizes glucose predominantly by glycolysis and fermentation. We have recently shown that altered chromatin structure in yeast induces respiration by a mechanism that requires transport and metabolism of pyruvate in mitochondria. However, how pyruvate controls the transcriptional responses underlying the metabolic switch from fermentation to respiration is unknown. Here, we report that this pyruvate effect involves heme. We found that heme induces transcription of HAP4, the transcriptional activation subunit of the Hap2/3/4/5p complex, required for growth on nonfermentable carbon sources, in a Hap1p- and Hap2/3/4/5p-dependent manner. Increasing cellular heme levels by inactivating ROX1, which encodes a repressor of many hypoxic genes, or by overexpressing HEM3 or HEM12 induced respiration and elevated ATP levels. Increased heme synthesis, even under conditions of glucose repression, activated Hap1p and the Hap2/3/4/5p complex and induced transcription of HAP4 and genes required for the tricarboxylic acid (TCA) cycle, electron transport chain, and oxidative phosphorylation, leading to a switch from fermentation to respiration. Conversely, inhibiting metabolic flux into the TCA cycle reduced cellular heme levels and HAP4 transcription. Together, our results indicate that the glucose-mediated repression of respiration in budding yeast is at least partly due to the low cellular heme level.
Collapse
Affiliation(s)
- Tiantian Zhang
- From the Department of Biological Sciences, St. John's University, Queens, New York 11439
| | - Pengli Bu
- From the Department of Biological Sciences, St. John's University, Queens, New York 11439
| | - Joey Zeng
- From the Department of Biological Sciences, St. John's University, Queens, New York 11439
| | - Ales Vancura
- From the Department of Biological Sciences, St. John's University, Queens, New York 11439
| |
Collapse
|
35
|
Willis SD, Hossian AKMN, Evans N, Hickman MJ. Measuring mRNA Levels Over Time During the Yeast S. cerevisiae Hypoxic Response. J Vis Exp 2017:56226. [PMID: 28829420 PMCID: PMC5614221 DOI: 10.3791/56226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Complex changes in gene expression typically mediate a large portion of a cellular response. Each gene may change expression with unique kinetics as the gene is regulated by the particular timing of one of many stimuli, signaling pathways or secondary effects. In order to capture the entire gene expression response to hypoxia in the yeast S. cerevisiae, RNA-seq analysis was used to monitor the mRNA levels of all genes at specific times after exposure to hypoxia. Hypoxia was established by growing cells in ~100% N2 gas. Importantly, unlike other hypoxic studies, ergosterol and unsaturated fatty acids were not added to the media because these metabolites affect gene expression. Time points were chosen in the range of 0 - 4 h after hypoxia because that period captures the major changes in gene expression. At each time point, mid-log hypoxic cells were quickly filtered and frozen, limiting exposure to O2 and concomitant changes in gene expression. Total RNA was extracted from cells and used to enrich for mRNA, which was then converted to cDNA. From this cDNA, multiplex libraries were created and eight or more samples were sequenced in one lane of a next-generation sequencer. A post-sequencing pipeline is described, which includes quality base trimming, read mapping and determining the number of reads per gene. DESeq2 within the R statistical environment was used to identify genes that change significantly at any one of the hypoxic time points. Analysis of three biological replicates revealed high reproducibility, genes of differing kinetics and a large number of expected O2-regulated genes. These methods can be used to study how the cells of various organisms respond to hypoxia over time and adapted to study gene expression during other cellular responses.
Collapse
Affiliation(s)
- Stephen D Willis
- Department of Molecular Biology, Rowan School of Osteopathic Medicine
| | | | - Nathan Evans
- Department of Biological Sciences, Rowan University
| | | |
Collapse
|
36
|
Jin M, Fuller GG, Han T, Yao Y, Alessi AF, Freeberg MA, Roach N, Moresco JJ, Karnovsky A, Baba M, Yates JR, Gitler AD, Inoki K, Klionsky DJ, Kim JK. Glycolytic Enzymes Coalesce in G Bodies under Hypoxic Stress. Cell Rep 2017; 20:895-908. [PMID: 28746874 PMCID: PMC5586494 DOI: 10.1016/j.celrep.2017.06.082] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 06/12/2017] [Accepted: 06/27/2017] [Indexed: 12/15/2022] Open
Abstract
Glycolysis is upregulated under conditions such as hypoxia and high energy demand to promote cell proliferation, although the mechanism remains poorly understood. We find that hypoxia in Saccharomyces cerevisiae induces concentration of glycolytic enzymes, including the Pfk2p subunit of the rate-limiting phosphofructokinase, into a single, non-membrane-bound granule termed the "glycolytic body" or "G body." A yeast kinome screen identifies the yeast ortholog of AMP-activated protein kinase, Snf1p, as necessary for G-body formation. Many G-body components identified by proteomics are required for G-body integrity. Cells incapable of forming G bodies in hypoxia display abnormal cell division and produce inviable daughter cells. Conversely, cells with G bodies show increased glucose consumption and decreased levels of glycolytic intermediates. Importantly, G bodies form in human hepatocarcinoma cells in hypoxia. Together, our results suggest that G body formation is a conserved, adaptive response to increase glycolytic output during hypoxia or tumorigenesis.
Collapse
Affiliation(s)
- Meiyan Jin
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109,Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109 USA
| | | | - Ting Han
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109,Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109 USA
| | - Yao Yao
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109
| | - Amelia F Alessi
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109
| | - Mallory A Freeberg
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109 USA
| | | | - James J Moresco
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037 USA
| | - Alla Karnovsky
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109 USA
| | - Misuzu Baba
- Research Institute for Science and Technology, Kogakuin University, Hachioji, Tokyo 192-0015 Japan
| | - John R Yates
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037 USA
| | - Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305 USA
| | - Ken Inoki
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109,Department of Molecular and Integrative Physiology and the Division of Nephrology in the Department of Internal Medicine
| | - Daniel J Klionsky
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109,Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109 USA,corresponding authors: John K Kim, Ph.D., Department of Biology, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD, 21218-2683, . Daniel J Klionsky, Ph.D., Life Sciences Institute, Department of Molecular, Cellular and Developmental Biology, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216,
| | - John K Kim
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109,corresponding authors: John K Kim, Ph.D., Department of Biology, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD, 21218-2683, . Daniel J Klionsky, Ph.D., Life Sciences Institute, Department of Molecular, Cellular and Developmental Biology, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216,
| |
Collapse
|
37
|
Epigenetic Transcriptional Memory of GAL Genes Depends on Growth in Glucose and the Tup1 Transcription Factor in Saccharomyces cerevisiae. Genetics 2017; 206:1895-1907. [PMID: 28607146 DOI: 10.1534/genetics.117.201632] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 06/09/2017] [Indexed: 01/01/2023] Open
Abstract
Previously expressed inducible genes can remain poised for faster reactivation for multiple cell divisions, a conserved phenomenon called epigenetic transcriptional memory. The GAL genes in Saccharomyces cerevisiae show faster reactivation for up to seven generations after being repressed. During memory, previously produced Gal1 protein enhances the rate of reactivation of GAL1, GAL10, GAL2, and GAL7 These genes also interact with the nuclear pore complex (NPC) and localize to the nuclear periphery both when active and during memory. Peripheral localization of GAL1 during memory requires the Gal1 protein, a memory-specific cis-acting element in the promoter, and the NPC protein Nup100 However, unlike other examples of transcriptional memory, the interaction with NPC is not required for faster GAL gene reactivation. Rather, downstream of Gal1, the Tup1 transcription factor and growth in glucose promote GAL transcriptional memory. Cells only show signs of memory and only benefit from memory when growing in glucose. Tup1 promotes memory-specific chromatin changes at the GAL1 promoter: incorporation of histone variant H2A.Z and dimethylation of histone H3, lysine 4. Tup1 and H2A.Z function downstream of Gal1 to promote binding of a preinitiation form of RNA Polymerase II at the GAL1 promoter, poising the gene for faster reactivation. This mechanism allows cells to integrate a previous experience (growth in galactose, reflected by Gal1 levels) with current conditions (growth in glucose, potentially through Tup1 function) to overcome repression and to poise critical GAL genes for future reactivation.
Collapse
|
38
|
Joshua IM, Höfken T. From Lipid Homeostasis to Differentiation: Old and New Functions of the Zinc Cluster Proteins Ecm22, Upc2, Sut1 and Sut2. Int J Mol Sci 2017; 18:ijms18040772. [PMID: 28379181 PMCID: PMC5412356 DOI: 10.3390/ijms18040772] [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: 02/28/2017] [Revised: 03/27/2017] [Accepted: 03/31/2017] [Indexed: 12/27/2022] Open
Abstract
Zinc cluster proteins are a large family of transcriptional regulators with a wide range of biological functions. The zinc cluster proteins Ecm22, Upc2, Sut1 and Sut2 have initially been identified as regulators of sterol import in the budding yeast Saccharomyces cerevisiae. These proteins also control adaptations to anaerobic growth, sterol biosynthesis as well as filamentation and mating. Orthologs of these zinc cluster proteins have been identified in several species of Candida. Upc2 plays a critical role in antifungal resistance in these important human fungal pathogens. Upc2 is therefore an interesting potential target for novel antifungals. In this review we discuss the functions, mode of actions and regulation of Ecm22, Upc2, Sut1 and Sut2 in budding yeast and Candida.
Collapse
Affiliation(s)
| | - Thomas Höfken
- Division of Biosciences, Brunel University London, Uxbridge UB8 3PH, UK.
| |
Collapse
|
39
|
Maurer MJ, Sutardja L, Pinel D, Bauer S, Muehlbauer AL, Ames TD, Skerker JM, Arkin AP. Quantitative Trait Loci (QTL)-Guided Metabolic Engineering of a Complex Trait. ACS Synth Biol 2017; 6:566-581. [PMID: 27936603 DOI: 10.1021/acssynbio.6b00264] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Engineering complex phenotypes for industrial and synthetic biology applications is difficult and often confounds rational design. Bioethanol production from lignocellulosic feedstocks is a complex trait that requires multiple host systems to utilize, detoxify, and metabolize a mixture of sugars and inhibitors present in plant hydrolysates. Here, we demonstrate an integrated approach to discovering and optimizing host factors that impact fitness of Saccharomyces cerevisiae during fermentation of a Miscanthus x giganteus plant hydrolysate. We first used high-resolution Quantitative Trait Loci (QTL) mapping and systematic bulk Reciprocal Hemizygosity Analysis (bRHA) to discover 17 loci that differentiate hydrolysate tolerance between an industrially related (JAY291) and a laboratory (S288C) strain. We then used this data to identify a subset of favorable allelic loci that were most amenable for strain engineering. Guided by this "genetic blueprint", and using a dual-guide Cas9-based method to efficiently perform multikilobase locus replacements, we engineered an S288C-derived strain with superior hydrolysate tolerance than JAY291. Our methods should be generalizable to engineering any complex trait in S. cerevisiae, as well as other organisms.
Collapse
Affiliation(s)
- Matthew J. Maurer
- Energy Biosciences Institute and ‡Department of
Bioengineering, University of California, Berkeley, California 94720, United States
- Biological Systems and Engineering Division, and ∥Environmental
Genomics and Systems
Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Lawrence Sutardja
- Energy Biosciences Institute and ‡Department of
Bioengineering, University of California, Berkeley, California 94720, United States
- Biological Systems and Engineering Division, and ∥Environmental
Genomics and Systems
Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Dominic Pinel
- Energy Biosciences Institute and ‡Department of
Bioengineering, University of California, Berkeley, California 94720, United States
- Biological Systems and Engineering Division, and ∥Environmental
Genomics and Systems
Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Stefan Bauer
- Energy Biosciences Institute and ‡Department of
Bioengineering, University of California, Berkeley, California 94720, United States
- Biological Systems and Engineering Division, and ∥Environmental
Genomics and Systems
Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Amanda L. Muehlbauer
- Energy Biosciences Institute and ‡Department of
Bioengineering, University of California, Berkeley, California 94720, United States
- Biological Systems and Engineering Division, and ∥Environmental
Genomics and Systems
Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Tyler D. Ames
- Energy Biosciences Institute and ‡Department of
Bioengineering, University of California, Berkeley, California 94720, United States
- Biological Systems and Engineering Division, and ∥Environmental
Genomics and Systems
Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Jeffrey M. Skerker
- Energy Biosciences Institute and ‡Department of
Bioengineering, University of California, Berkeley, California 94720, United States
- Biological Systems and Engineering Division, and ∥Environmental
Genomics and Systems
Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Adam P. Arkin
- Energy Biosciences Institute and ‡Department of
Bioengineering, University of California, Berkeley, California 94720, United States
- Biological Systems and Engineering Division, and ∥Environmental
Genomics and Systems
Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| |
Collapse
|
40
|
Time-Course Analysis of Gene Expression During the Saccharomyces cerevisiae Hypoxic Response. G3-GENES GENOMES GENETICS 2017; 7:221-231. [PMID: 27883312 PMCID: PMC5217111 DOI: 10.1534/g3.116.034991] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Many cells experience hypoxia, or low oxygen, and respond by dramatically altering gene expression. In the yeast Saccharomyces cerevisiae, genes that respond are required for many oxygen-dependent cellular processes, such as respiration, biosynthesis, and redox regulation. To more fully characterize the global response to hypoxia, we exposed yeast to hypoxic conditions, extracted RNA at different times, and performed RNA sequencing (RNA-seq) analysis. Time-course statistical analysis revealed hundreds of genes that changed expression by up to 550-fold. The genes responded with varying kinetics suggesting that multiple regulatory pathways are involved. We identified most known oxygen-regulated genes and also uncovered new regulated genes. Reverse transcription-quantitative PCR (RT-qPCR) analysis confirmed that the lysine methyltransferase EFM6 and the recombinase DMC1, both conserved in humans, are indeed oxygen-responsive. Looking more broadly, oxygen-regulated genes participate in expected processes like respiration and lipid metabolism, but also in unexpected processes like amino acid and vitamin metabolism. Using principle component analysis, we discovered that the hypoxic response largely occurs during the first 2 hr and then a new steady-state expression state is achieved. Moreover, we show that the oxygen-dependent genes are not part of the previously described environmental stress response (ESR) consisting of genes that respond to diverse types of stress. While hypoxia appears to cause a transient stress, the hypoxic response is mostly characterized by a transition to a new state of gene expression. In summary, our results reveal that hypoxia causes widespread and complex changes in gene expression to prepare the cell to function with little or no oxygen.
Collapse
|
41
|
Eisenberg-Bord M, Schuldiner M. Ground control to major TOM: mitochondria-nucleus communication. FEBS J 2016; 284:196-210. [PMID: 27283924 DOI: 10.1111/febs.13778] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Revised: 05/23/2016] [Accepted: 06/08/2016] [Indexed: 01/13/2023]
Abstract
Mitochondria have crucial functions in the cell, including ATP generation, iron-sulfur cluster biogenesis, nucleotide biosynthesis, and amino acid metabolism. All of these functions require tight regulation on mitochondrial activity and homeostasis. As mitochondria biogenesis is controlled by the nucleus and almost all mitochondrial proteins are encoded by nuclear genes, a tight communication network between mitochondria and the nucleus has evolved, which includes signaling cascades, proteins which are dual-localized to the two compartments, and sensing of mitochondrial products by nuclear proteins. All of these enable a crosstalk between mitochondria and the nucleus that allows the 'ground control' to get information on mitochondria's status. Such information facilitates the creation of a cellular balance of mitochondrial status with energetic needs. This communication also allows a transcriptional response in case mitochondrial function is impaired aimed to restore mitochondrial homeostasis. As mitochondrial dysfunction is related to a growing number of genetic diseases as well as neurodegenerative conditions and aging, elucidating the mechanisms governing the mitochondrial/nuclear communication should progress a better understanding of mitochondrial dysfunctions.
Collapse
Affiliation(s)
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|
42
|
The Swi3 protein plays a unique role in regulating respiration in eukaryotes. Biosci Rep 2016; 36:BSR20160083. [PMID: 27190130 PMCID: PMC5293592 DOI: 10.1042/bsr20160083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 05/17/2016] [Indexed: 01/08/2023] Open
Abstract
Recent experimental evidence increasingly shows that the dysregulation of cellular bioenergetics is associated with a wide array of common human diseases, including cancer, neurological diseases and diabetes. Respiration provides a vital source of cellular energy for most eukaryotic cells, particularly high energy demanding cells. However, the understanding of how respiration is globally regulated is very limited. Interestingly, recent evidence suggests that Swi3 is an important regulator of respiration genes in yeast. In this report, we performed an array of biochemical and genetic experiments and computational analysis to directly evaluate the function of Swi3 and its human homologues in regulating respiration. First, we showed, by computational analysis and measurements of oxygen consumption and promoter activities, that Swi3, not Swi2, regulates genes encoding functions involved in respiration and oxygen consumption. Biochemical analysis showed that the levels of mitochondrial respiratory chain complexes were substantially increased in Δswi3 cells, compared with the parent cells. Additionally, our data showed that Swi3 strongly affects haem/oxygen-dependent activation of respiration gene promoters whereas Swi2 affects only the basal, haem-independent activities of these promoters. We found that increased expression of aerobic expression genes is correlated with increased oxygen consumption and growth rates in Δswi3 cells in air. Furthermore, using computational analysis and RNAi knockdown, we showed that the mammalian Swi3 BAF155 and BAF170 regulate respiration in HeLa cells. Together, these experimental and computational data demonstrated that Swi3 and its mammalian homologues are key regulators in regulating respiration.
Collapse
|
43
|
Sun X, Wang Z, Guo X, Li H, Gu Z. Coordinated Evolution of Transcriptional and Post-Transcriptional Regulation for Mitochondrial Functions in Yeast Strains. PLoS One 2016; 11:e0153523. [PMID: 27077367 PMCID: PMC4831757 DOI: 10.1371/journal.pone.0153523] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 03/30/2016] [Indexed: 11/19/2022] Open
Abstract
Evolution of gene regulation has been proposed to play an important role in environmental adaptation. Exploring mechanisms underlying coordinated evolutionary changes at various levels of gene regulation could shed new light on how organism adapt in nature. In this study, we focused on regulatory differences between a laboratory Saccharomyces cerevisiae strain BY4742 and a pathogenic S. cerevisiae strain, YJM789. The two strains diverge in many features, including growth rate, morphology, high temperature tolerance, and pathogenicity. Our RNA-Seq and ribosomal footprint profiling data showed that gene expression differences are pervasive, and genes functioning in mitochondria are mostly divergent between the two strains at both transcriptional and translational levels. Combining functional genomics data from other yeast strains, we further demonstrated that significant divergence of expression for genes functioning in the electron transport chain (ETC) was likely caused by differential expression of a transcriptional factor, HAP4, and that post-transcriptional regulation mediated by an RNA-binding protein, PUF3, likely led to expression divergence for genes involved in mitochondrial translation. We also explored mito-nuclear interactions via mitochondrial DNA replacement between strains. Although the two mitochondrial genomes harbor substantial sequence divergence, neither growth nor gene expression were affected by mitochondrial DNA replacement in both fermentative and respiratory growth media, indicating compatible mitochondrial and nuclear genomes between these two strains in the tested conditions. Collectively, we used mitochondrial functions as an example to demonstrate for the first time that evolution at both transcriptional and post-transcriptional levels could lead to coordinated regulatory changes underlying strain specific functional variations.
Collapse
Affiliation(s)
- Xuepeng Sun
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, United States of America
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, P.R. China
| | - Zhe Wang
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, United States of America
| | - Xiaoxian Guo
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, United States of America
| | - Hongye Li
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, P.R. China
| | - Zhenglong Gu
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, United States of America
- * E-mail:
| |
Collapse
|
44
|
Çakır T. Reporter pathway analysis from transcriptome data: Metabolite-centric versus Reaction-centric approach. Sci Rep 2015; 5:14563. [PMID: 26411587 PMCID: PMC4585941 DOI: 10.1038/srep14563] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Accepted: 08/28/2015] [Indexed: 12/16/2022] Open
Abstract
A systems-based investigation of the effect of perturbations on metabolic machinery is crucial to elucidate the mechanism behind perturbations. One way to investigate the perturbation-induced changes within the cell metabolism is to focus on pathway-level effects. In this study, three different perturbation types (genetic, environmental and disease-based) are analyzed to compute a list of reporter pathways, metabolic pathways which are significantly affected from a perturbation. The most common omics data type, transcriptome, is used as an input to the bioinformatic analysis. The pathways are scored by two alternative approaches: by averaging the changes in the expression levels of the genes controlling the associated reactions (reaction-centric), and by averaging the changes in the associated metabolites which were scored based on the associated genes (metabolite-centric). The analysis reveals the superiority of the novel metabolite-centric approach over the commonly used reaction-centric approach since it is based on metabolites which better represent the cross-talk among different pathways, enabling a more global and realistic cataloguing of network-wide perturbation effects.
Collapse
Affiliation(s)
- Tunahan Çakır
- Gebze Technical University, Department of Bioengineering, 41400, Gebze, Kocaeli, Turkey
| |
Collapse
|
45
|
Abstract
We define a measure of coherent activity for gene regulatory networks, a property that reflects the unity of purpose between the regulatory agents with a common target. We propose that such harmonious regulatory action is desirable under a demand for energy efficiency and may be selected for under evolutionary pressures. We consider two recent models of the cell-cycle regulatory network of the yeast, Saccharomyces cerevisiae as a case study and calculate their degree of coherence. A comparison with random networks of similar size and composition reveals that the yeast's cell-cycle regulation is wired to yield an exceptionally high level of coherent regulatory activity. We also investigate the mean degree of coherence as a function of the network size, connectivity and the fraction of repressory/activatory interactions.
Collapse
Affiliation(s)
- Neşe Aral
- Department of Physics, Koç University, Rumelifeneri Yolu Sarıyer 34450, Istanbul, Turkey
| | | |
Collapse
|
46
|
Merhej J, Delaveau T, Guitard J, Palancade B, Hennequin C, Garcia M, Lelandais G, Devaux F. Yap7 is a transcriptional repressor of nitric oxide oxidase in yeasts, which arose from neofunctionalization after whole genome duplication. Mol Microbiol 2015; 96:951-72. [DOI: 10.1111/mmi.12983] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2015] [Indexed: 11/27/2022]
Affiliation(s)
- Jawad Merhej
- Sorbonne Universités, UPMC Univ. Paris 06, Institut de Biologie Paris Seine UMR 7238; Laboratoire de biologie computationnelle et quantitative; F-75006 Paris France
- CNRS, UMR 7238; Laboratoire de biologie computationnelle et quantitative; F-75006 Paris France
| | - Thierry Delaveau
- Sorbonne Universités, UPMC Univ. Paris 06, Institut de Biologie Paris Seine UMR 7238; Laboratoire de biologie computationnelle et quantitative; F-75006 Paris France
- CNRS, UMR 7238; Laboratoire de biologie computationnelle et quantitative; F-75006 Paris France
| | - Juliette Guitard
- Sorbonne Universités, UPMC Univ Paris 06, CR7; Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris); 91 Bd de l'hôpital F-75013 Paris France
- Inserm; U1135; CIMI-Paris; 91 Bd de l'hôpital F-75013 Paris France
- Assistance Publique-Hôpitaux de Paris, Hôpital St Antoine; Service de Parasitologie-Mycologie; F-75012 Paris France
- CNRS; ERL 8255; CIMI-Paris; 91 Bd de l'hôpital F-75013 Paris France
| | - Benoit Palancade
- Institut Jacques Monod, CNRS, UMR 7592, Univ Paris Diderot; Sorbonne Paris Cité; F-75205 Paris France
| | - Christophe Hennequin
- Sorbonne Universités, UPMC Univ Paris 06, CR7; Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris); 91 Bd de l'hôpital F-75013 Paris France
- Inserm; U1135; CIMI-Paris; 91 Bd de l'hôpital F-75013 Paris France
- Assistance Publique-Hôpitaux de Paris, Hôpital St Antoine; Service de Parasitologie-Mycologie; F-75012 Paris France
- CNRS; ERL 8255; CIMI-Paris; 91 Bd de l'hôpital F-75013 Paris France
| | - Mathilde Garcia
- Sorbonne Universités, UPMC Univ. Paris 06, Institut de Biologie Paris Seine UMR 7238; Laboratoire de biologie computationnelle et quantitative; F-75006 Paris France
- CNRS, UMR 7238; Laboratoire de biologie computationnelle et quantitative; F-75006 Paris France
| | - Gaëlle Lelandais
- Institut Jacques Monod, CNRS, UMR 7592, Univ Paris Diderot; Sorbonne Paris Cité; F-75205 Paris France
| | - Frédéric Devaux
- Sorbonne Universités, UPMC Univ. Paris 06, Institut de Biologie Paris Seine UMR 7238; Laboratoire de biologie computationnelle et quantitative; F-75006 Paris France
- CNRS, UMR 7238; Laboratoire de biologie computationnelle et quantitative; F-75006 Paris France
| |
Collapse
|
47
|
ChIP-seq and in vivo transcriptome analyses of the Aspergillus fumigatus SREBP SrbA reveals a new regulator of the fungal hypoxia response and virulence. PLoS Pathog 2014; 10:e1004487. [PMID: 25375670 PMCID: PMC4223079 DOI: 10.1371/journal.ppat.1004487] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 09/23/2014] [Indexed: 12/21/2022] Open
Abstract
The Aspergillus fumigatus sterol regulatory element binding protein (SREBP) SrbA belongs to the basic Helix-Loop-Helix (bHLH) family of transcription factors and is crucial for antifungal drug resistance and virulence. The latter phenotype is especially striking, as loss of SrbA results in complete loss of virulence in murine models of invasive pulmonary aspergillosis (IPA). How fungal SREBPs mediate fungal virulence is unknown, though it has been suggested that lack of growth in hypoxic conditions accounts for the attenuated virulence. To further understand the role of SrbA in fungal infection site pathobiology, chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq) was used to identify genes under direct SrbA transcriptional regulation in hypoxia. These results confirmed the direct regulation of ergosterol biosynthesis and iron uptake by SrbA in hypoxia and revealed new roles for SrbA in nitrate assimilation and heme biosynthesis. Moreover, functional characterization of an SrbA target gene with sequence similarity to SrbA identified a new transcriptional regulator of the fungal hypoxia response and virulence, SrbB. SrbB co-regulates genes involved in heme biosynthesis and demethylation of C4-sterols with SrbA in hypoxic conditions. However, SrbB also has regulatory functions independent of SrbA including regulation of carbohydrate metabolism. Loss of SrbB markedly attenuates A. fumigatus virulence, and loss of both SREBPs further reduces in vivo fungal growth. These data suggest that both A. fumigatus SREBPs are critical for hypoxia adaptation and virulence and reveal new insights into SREBPs' complex role in infection site adaptation and fungal virulence. Despite improvements in diagnostics and antifungal drug treatments, mortality rates from invasive mold infections remain high. Defining the fungal adaptation and growth mechanisms at the infection site microenvironment is one research focus that is expected to improve treatment of established invasive fungal infections. The Aspergillus fumigatus transcription factor SrbA is a major regulator of the fungal response to hypoxia found at sites of invasive fungal growth in vivo. In this study, new insights into how SrbA mediates hypoxia adaptation and virulence were revealed through identification of direct transcriptional targets of SrbA under hypoxic conditions. A major novel finding from these studies is the identification of a critical role in fungal hypoxia adaptation and virulence of an SrbA target gene, srbB, which is also in the SREBP family. SrbB plays a major role in regulation of heme biosynthesis and carbohydrate metabolism early in the response to hypoxia. The discovery of SrbA-dependent regulation of srbB gene expression, and the target genes they regulate opens new avenues to understand how SREBPs and their target genes mediate adaptation to the in vivo infection site microenvironment and responses to current antifungal therapies.
Collapse
|
48
|
Identification of genomic binding sites for Candida glabrata Pdr1 transcription factor in wild-type and ρ0 cells. Antimicrob Agents Chemother 2014; 58:6904-12. [PMID: 25199772 DOI: 10.1128/aac.03921-14] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The fungal pathogen Candida glabrata is an emerging cause of candidiasis in part owing to its robust ability to acquire tolerance to the major clinical antifungal drug fluconazole. Similar to the related species Candida albicans, C. glabrata most typically gains azole tolerance via transcriptional induction of a suite of resistance genes, including a locus encoding an ABCG-type ATP-binding cassette (ABC) transporter that is referred to as CDR1 in Candida species. In C. glabrata, CDR1 expression is controlled primarily by the activity of a transcriptional activator protein called Pdr1. Strains exhibiting reduced azole susceptibility often contain substitution mutations in PDR1 that in turn lead to elevated mRNA levels of target genes with associated azole resistance. Pdr1 activity is also induced upon loss of the mitochondrial genome status and upon challenge by azole drugs. While extensive analyses of the transcriptional effects of Pdr1 have identified a number of genes that are regulated by this factor, we cannot yet separate direct from indirect target genes. Here we used chromatin immunoprecipitation (ChIP) coupled with high-throughput sequencing (ChIP-seq) to identify the promoters and associated genes directly regulated by Pdr1. These genes include many that are shared with the yeast Saccharomyces cerevisiae but others that are unique to C. glabrata, including the ABC transporter-encoding locus YBT1, genes involved in DNA repair, and several others. These data provide the outline for understanding the primary response genes involved in production of Pdr1-dependent azole resistance in C. glabrata.
Collapse
|
49
|
González-Mariscal I, García-Testón E, Padilla S, Martín-Montalvo A, Pomares Viciana T, Vazquez-Fonseca L, Gandolfo Domínguez P, Santos-Ocaña C. The regulation of coenzyme q biosynthesis in eukaryotic cells: all that yeast can tell us. Mol Syndromol 2014; 5:107-18. [PMID: 25126044 DOI: 10.1159/000362897] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Coenzyme Q (CoQ) is a mitochondrial lipid, which functions mainly as an electron carrier from complex I or II to complex III at the mitochondrial inner membrane, and also as antioxidant in cell membranes. CoQ is needed as electron acceptor in β-oxidation of fatty acids and pyridine nucleotide biosynthesis, and it is responsible for opening the mitochondrial permeability transition pore. The yeast model has been very useful to analyze the synthesis of CoQ, and therefore, most of the knowledge about its regulation was obtained from the Saccharomyces cerevisiae model. CoQ biosynthesis is regulated to support 2 processes: the bioenergetic metabolism and the antioxidant defense. Alterations of the carbon source in yeast, or in nutrient availability in yeasts or mammalian cells, upregulate genes encoding proteins involved in CoQ synthesis. Oxidative stress, generated by chemical or physical agents or by serum deprivation, modifies specifically the expression of some COQ genes by means of stress transcription factors such as Msn2/4p, Yap1p or Hsf1p. In general, the induction of COQ gene expression produced by metabolic changes or stress is modulated downstream by other regulatory mechanisms such as the protein import to mitochondria, the assembly of a multi-enzymatic complex composed by Coq proteins and also the existence of a phosphorylation cycle that regulates the last steps of CoQ biosynthesis. The CoQ biosynthetic complex assembly starts with the production of a nucleating lipid such as HHB by the action of the Coq2 protein. Then, the Coq4 protein recognizes the precursor HHB acting as the nucleus of the complex. The activity of Coq8p, probably as kinase, allows the formation of an initial pre-complex containing all Coq proteins with the exception of Coq7p. This pre-complex leads to the synthesis of 5-demethoxy-Q6 (DMQ6), the Coq7p substrate. When de novo CoQ biosynthesis is required, Coq7p becomes dephosphorylated by the action of Ptc7p increasing the synthesis rate of CoQ6. This critical model is needed for a better understanding of CoQ biosynthesis. Taking into account that patients with CoQ10 deficiency maintain to some extent the machinery to synthesize CoQ, new promising strategies for the treatment of CoQ10 deficiency will require a better understanding of the regulation of CoQ biosynthesis in the future.
Collapse
Affiliation(s)
| | - Elena García-Testón
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide - CSIC, and CIBERER Instituto de Salud Carlos III, Seville, Spain
| | - Sergio Padilla
- Sanford Children's Health Research Center, Sanford Research USD, Sioux Falls, S. Dak., USA
| | | | - Teresa Pomares Viciana
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide - CSIC, and CIBERER Instituto de Salud Carlos III, Seville, Spain
| | - Luis Vazquez-Fonseca
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide - CSIC, and CIBERER Instituto de Salud Carlos III, Seville, Spain
| | - Pablo Gandolfo Domínguez
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide - CSIC, and CIBERER Instituto de Salud Carlos III, Seville, Spain
| | - Carlos Santos-Ocaña
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide - CSIC, and CIBERER Instituto de Salud Carlos III, Seville, Spain
| |
Collapse
|
50
|
Fleming AB, Beggs S, Church M, Tsukihashi Y, Pennings S. The yeast Cyc8-Tup1 complex cooperates with Hda1p and Rpd3p histone deacetylases to robustly repress transcription of the subtelomeric FLO1 gene. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1839:1242-55. [PMID: 25106892 PMCID: PMC4316177 DOI: 10.1016/j.bbagrm.2014.07.022] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 07/28/2014] [Accepted: 07/29/2014] [Indexed: 12/02/2022]
Abstract
We demonstrate that the yeast flocculation gene, FLO1, is representative of a distinct subset of subtelomeric genes that are robustly repressed by the Cyc8–Tup1 complex. We have examined Cyc8–Tup1 localisation, histone acetylation and long-range chromatin remodelling within the extensive FLO1 upstream region. We show that Cyc8–Tup1 is localised in a DNase I hypersensitive site within an ordered array of strongly positioned nucleosomes around − 700 base pairs upstream of the transcription start site. In cyc8 deletion mutant strains, Tup1p localisation is absent, with concomitant histone hyperacetylation of adjacent regions at the FLO1 promoter. This is accompanied by extensive histone depletion across the upstream region and gene activation. The yeast histone deacetylases, Hda1p and Rpd3p, occupy the repressed FLO1 promoter region in a Cyc8–Tup1 dependent manner and coordinate histone deacetylation, nucleosome stabilisation and gene repression. Moreover, we show that the ATP-dependent chromatin remodelling complex Swi–Snf occupies the site vacated by Cyc8–Tup1 in a cyc8 mutant. These data suggest that distinctly bound Cyc8–Tup1 cooperates with Hda1p and Rpd3p to establish or maintain an extensive array of strongly positioned, deacetylated nucleosomes over the FLO1 promoter and upstream region which inhibit histone acetylation, block Swi–Snf binding and prevent transcription. Cyc8–Tup1 repression activity is enriched at chromosome subtelomeric regions. The subtelomeric FLO1 gene is subject to chromatin-mediated repression by Cyc8–Tup1. Cyc8–Tup1 promotes long-range nucleosome positioning and histone deacetylation. Hda1p and Rpd3p cooperate with Cyc8–Tup1 to facilitate this repressive chromatin. Swi–Snf directs extensive nucleosome remodelling when Cyc8–Tup1 is absent.
Collapse
Affiliation(s)
- Alastair B Fleming
- School of Genetics and Microbiology, Trinity College Dublin, College Green, Dublin 2, Ireland; School of Biomedical Sciences, University of Edinburgh, Edinburgh, EH8 9XD, UK.
| | - Suzanne Beggs
- School of Genetics and Microbiology, Trinity College Dublin, College Green, Dublin 2, Ireland
| | - Michael Church
- School of Genetics and Microbiology, Trinity College Dublin, College Green, Dublin 2, Ireland
| | | | - Sari Pennings
- School of Biomedical Sciences, University of Edinburgh, Edinburgh, EH8 9XD, UK; Queen's Medical Research Institute, University of Edinburgh, Edinburgh, EH16 4TJ, UK
| |
Collapse
|