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Tan Q, Xiao J, Chen J, Wang Y, Zhang Z, Zhao T, Li Y. ifDEEPre: large protein language-based deep learning enables interpretable and fast predictions of enzyme commission numbers. Brief Bioinform 2024; 25:bbae225. [PMID: 38942594 PMCID: PMC11213619 DOI: 10.1093/bib/bbae225] [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: 12/11/2023] [Revised: 03/26/2024] [Accepted: 04/22/2024] [Indexed: 06/30/2024] Open
Abstract
Accurate understanding of the biological functions of enzymes is vital for various tasks in both pathologies and industrial biotechnology. However, the existing methods are usually not fast enough and lack explanations on the prediction results, which severely limits their real-world applications. Following our previous work, DEEPre, we propose a new interpretable and fast version (ifDEEPre) by designing novel self-guided attention and incorporating biological knowledge learned via large protein language models to accurately predict the commission numbers of enzymes and confirm their functions. Novel self-guided attention is designed to optimize the unique contributions of representations, automatically detecting key protein motifs to provide meaningful interpretations. Representations learned from raw protein sequences are strictly screened to improve the running speed of the framework, 50 times faster than DEEPre while requiring 12.89 times smaller storage space. Large language modules are incorporated to learn physical properties from hundreds of millions of proteins, extending biological knowledge of the whole network. Extensive experiments indicate that ifDEEPre outperforms all the current methods, achieving more than 14.22% larger F1-score on the NEW dataset. Furthermore, the trained ifDEEPre models accurately capture multi-level protein biological patterns and infer evolutionary trends of enzymes by taking only raw sequences without label information. Meanwhile, ifDEEPre predicts the evolutionary relationships between different yeast sub-species, which are highly consistent with the ground truth. Case studies indicate that ifDEEPre can detect key amino acid motifs, which have important implications for designing novel enzymes. A web server running ifDEEPre is available at https://proj.cse.cuhk.edu.hk/aihlab/ifdeepre/ to provide convenient services to the public. Meanwhile, ifDEEPre is freely available on GitHub at https://github.com/ml4bio/ifDEEPre/.
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Affiliation(s)
- Qingxiong Tan
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Jin Xiao
- Department of Computer Science, Hong Kong Baptist University, Hong Kong SAR, China
| | - Jiayang Chen
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Yixuan Wang
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Zeliang Zhang
- Department of Computer Science, University of Rochester, Rochester, New York State, USA
- School of Computer Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | | | - Yu Li
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong SAR, China
- The CUHK Shenzhen Research Institute, Nanshan, Shenzhen, China
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Bedekovic T, Usher J. Is There a Relationship Between Mating and Pathogenesis in Two Human Fungal Pathogens, Candida albicans and Candida glabrata?. CURRENT CLINICAL MICROBIOLOGY REPORTS 2023; 10:47-54. [PMID: 37151577 PMCID: PMC10154270 DOI: 10.1007/s40588-023-00192-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/30/2023] [Indexed: 05/09/2023]
Abstract
Purpose of Review Human fungal pathogens are rapidly increasing in incidence and readily able to evade the host immune responses. Our ability to study the genetic behind this has been limited due to the apparent lack of a sexual cycle and forward genetic tools. In this review, we discuss the evolution of mating, meiosis, and pathogenesis and if these processes are advantageous to pathogens. Recent Findings This review summarises what is currently known about the sexual cycles of two important human fungal pathogens, Candida albicans and Candida glabrata. This includes the identification of parasexual cycle in C. albicans and the observed low levels of recombination in C. glabrata populations. Summary In this review, we present what is currently known about the mating types and mating/sexual cycles of two clinically important human fungal pathogens, Candida albicans and Candida glabrata. We discuss the evolution of meiosis using the knowledge that has been amassed from the decades of studying Saccharomyces cerevisiae and how this can be applied to fungal pathogens. We further discuss how the evolution of pathogenesis has played a role in influencing mating processes in human fungal pathogens and compare sexual cycles between C. albicans and C. glabrata, highlighting knowledge gaps and suggesting how these two fungi have evolved distinct mating niches to allow the development of disease in a human host.
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Affiliation(s)
- Tina Bedekovic
- MRC Centre for Medical Mycology, Department of Biosciences, Geoffrey Pope Building, University of Exeter, Stocker Road, Exeter, EX4 4QD UK
| | - Jane Usher
- MRC Centre for Medical Mycology, Department of Biosciences, Geoffrey Pope Building, University of Exeter, Stocker Road, Exeter, EX4 4QD UK
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Transcriptional Response of Candida auris to the Mrr1 Inducers Methylglyoxal and Benomyl. mSphere 2022; 7:e0012422. [PMID: 35473297 PMCID: PMC9241502 DOI: 10.1128/msphere.00124-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Candida auris is an urgent threat to human health due to its rapid spread in health care settings and its repeated development of multidrug resistance. Diseases that increase risk for C. auris infection, such as diabetes, kidney failure, or immunocompromising conditions, are associated with elevated levels of methylglyoxal (MG), a reactive dicarbonyl compound derived from several metabolic processes. In other Candida species, expression of MG reductase enzymes that catabolize and detoxify MG are controlled by Mrr1, a multidrug resistance-associated transcription factor, and MG induces Mrr1 activity. Here, we used transcriptomics and genetic assays to determine that C. aurisMRR1a contributes to MG resistance, and that the main Mrr1a targets are an MG reductase and MDR1, which encodes a drug efflux protein. The C. auris Mrr1a regulon is smaller than Mrr1 regulons described in other species. In addition to MG, benomyl (BEN), a known Mrr1 stimulus, induces C. auris Mrr1 activity, and characterization of the MRR1a-dependent and -independent transcriptional responses revealed substantial overlap in genes that were differentially expressed in response to each compound. Additionally, we found that an MRR1 allele specific to one C. auris phylogenetic clade, clade III, encodes a hyperactive Mrr1 variant, and this activity correlated with higher MG resistance. C. aurisMRR1a alleles were functional in Candida lusitaniae and were inducible by BEN, but not by MG, suggesting that the two Mrr1 inducers act via different mechanisms. Together, the data presented in this work contribute to the understanding of Mrr1 activity and MG resistance in C. auris. IMPORTANCECandida auris is a fungal pathogen that has spread since its identification in 2009 and is of concern due to its high incidence of resistance against multiple classes of antifungal drugs. In other Candida species, the transcription factor Mrr1 plays a major role in resistance against azole antifungals and other toxins. More recently, Mrr1 has been recognized to contribute to resistance to methylglyoxal (MG), a toxic metabolic product that is often elevated in different disease states. MG can activate Mrr1 and its induction of Mdr1 which can protect against diverse challenges. The significance of this work lies in showing that MG is also an inducer of Mrr1 in C. auris, and that one of the major pathogenic C. auris lineages has an activating Mrr1 mutation that confers protection against MG.
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Okamoto M, Takahashi-Nakaguchi A, Tejima K, Sasamoto K, Yamaguchi M, Aoyama T, Nagi M, Tanabe K, Miyazaki Y, Nakayama H, Sasakawa C, Kajiwara S, Brown AJP, Teixeira MC, Chibana H. Erg25 Controls Host-Cholesterol Uptake Mediated by Aus1p-Associated Sterol-Rich Membrane Domains in Candida glabrata. Front Cell Dev Biol 2022; 10:820675. [PMID: 35399500 PMCID: PMC8988197 DOI: 10.3389/fcell.2022.820675] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 03/07/2022] [Indexed: 12/11/2022] Open
Abstract
The uptake of cholesterol from the host is closely linked to the proliferation of pathogenic fungi and protozoa during infection. For some pathogenic fungi, cholesterol uptake is an important strategy for decreasing susceptibility to antifungals that inhibit ergosterol biosynthesis. In this study, we show that Candida glabrata ERG25, which encodes an enzyme that demethylates 4,4-dimethylzymosterol, is required for cholesterol uptake from host serum. Based on the screening of C. glabrata conditional knockdown mutants for each gene involved in ergosterol biosynthesis, ERG25 knockdown was found to decrease lethality of infected mice. ERG25 knockdown impairs the plasma membrane localization of the sterol importer Aus1p, suggesting that the accumulated 4,4-dimethylzymosterol destabilizes the lipid domain with which Aus1p functionally associates. ERG25 knockdown further influences the structure of the membrane compartment of Can1p (MCC)/eisosomes (ergosterol-rich lipid domains), but not the localization of the membrane proteins Pma1p and Hxt1p, which localize to sterol-poor domains. In the sterol-rich lipid domain, Aus1p-contining domain was mostly independent of MCC/eisosomes, and the nature of these domains was also different: Ausp1-contining domain was a dynamic network-like domain, whereas the MCC/eisosomes was a static dot-like domain. However, deletion of MCC/eisosomes was observed to influence the localization of Aus1p after Aus1p was transported from the endoplasmic reticulum (ER) through the Golgi apparatus to the plasma membrane. These findings suggest that ERG25 plays a key role in stabilizing sterol-rich lipid domains, constituting a promising candidate target for antifungal therapy.
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Affiliation(s)
- Michiyo Okamoto
- Medical Mycology Research Center, Chiba University, Chiba, Japan
| | | | - Kengo Tejima
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Kaname Sasamoto
- Medical Mycology Research Center, Chiba University, Chiba, Japan
| | | | - Toshihiro Aoyama
- Department of Electronic and Information Engineering, Suzuka National College of Technology, Suzuka, Japan
| | - Minoru Nagi
- National Institute of Infectious Diseases, Tokyo, Japan
| | - Kohichi Tanabe
- Department of Food Science and Human Nutrition, Faculty of Agriculture, Ryukoku University, Otsu, Japan
| | | | - Hironobu Nakayama
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, Suzuka, Japan
| | - Chihiro Sasakawa
- Medical Mycology Research Center, Chiba University, Chiba, Japan
- Nippon Institute for Biological Science, Tokyo, Japan
| | - Susumu Kajiwara
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | | | - Miguel C. Teixeira
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Hiroji Chibana
- Medical Mycology Research Center, Chiba University, Chiba, Japan
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Galkina KV, Okamoto M, Chibana H, Knorre DA, Kajiwara S. Deletion of CDR1 reveals redox regulation of pleiotropic drug resistance in Candida glabrata. Biochimie 2020; 170:49-56. [DOI: 10.1016/j.biochi.2019.12.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 12/09/2019] [Indexed: 12/27/2022]
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Rodrigues-Pousada C, Devaux F, Caetano SM, Pimentel C, da Silva S, Cordeiro AC, Amaral C. Yeast AP-1 like transcription factors (Yap) and stress response: a current overview. MICROBIAL CELL 2019; 6:267-285. [PMID: 31172012 PMCID: PMC6545440 DOI: 10.15698/mic2019.06.679] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Yeast adaptation to stress has been extensively studied. It involves large reprogramming of genome expression operated by many, more or less specific, transcription factors. Here, we review our current knowledge on the function of the eight Yap transcription factors (Yap1 to Yap8) in Saccharomyces cerevisiae, which were shown to be involved in various stress responses. More precisely, Yap1 is activated under oxidative stress, Yap2/Cad1 under cadmium, Yap4/Cin5 and Yap6 under osmotic shock, Yap5 under iron overload and Yap8/Arr1 by arsenic compounds. Yap3 and Yap7 seem to be involved in hydroquinone and nitrosative stresses, respectively. The data presented in this article illustrate how much knowledge on the function of these Yap transcription factors is advanced. The evolution of the Yap family and its roles in various pathogenic and non-pathogenic fungal species is discussed in the last section.
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Affiliation(s)
- Claudina Rodrigues-Pousada
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| | - Frédéric Devaux
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, Laboratory of Computational and Quantitative Biology, F-75005, Paris, France
| | - Soraia M Caetano
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| | - Catarina Pimentel
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| | - Sofia da Silva
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| | - Ana Carolina Cordeiro
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| | - Catarina Amaral
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
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Denecker T, Durand W, Maupetit J, Hébert C, Camadro JM, Poulain P, Lelandais G. Pixel: a content management platform for quantitative omics data. PeerJ 2019; 7:e6623. [PMID: 30944779 PMCID: PMC6441322 DOI: 10.7717/peerj.6623] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 02/14/2019] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND In biology, high-throughput experimental technologies, also referred as "omics" technologies, are increasingly used in research laboratories. Several thousands of gene expression measurements can be obtained in a single experiment. Researchers are routinely facing the challenge to annotate, store, explore and mine all the biological information they have at their disposal. We present here the Pixel web application (Pixel Web App), an original content management platform to help people involved in a multi-omics biological project. METHODS The Pixel Web App is built with open source technologies and hosted on the collaborative development platform GitHub (https://github.com/Candihub/pixel). It is written in Python using the Django framework and stores all the data in a PostgreSQL database. It is developed in the open and licensed under the BSD 3-clause license. The Pixel Web App is also heavily tested with both unit and functional tests, a strong code coverage and continuous integration provided by CircleCI. To ease the development and the deployment of the Pixel Web App, Docker and Docker Compose are used to bundle the application as well as its dependencies. RESULTS The Pixel Web App offers researchers an intuitive way to annotate, store, explore and mine their multi-omics results. It can be installed on a personal computer or on a server to fit the needs of many users. In addition, anyone can enhance the application to better suit their needs, either by contributing directly on GitHub (encouraged) or by extending Pixel on their own. The Pixel Web App does not provide any computational programs to analyze the data. Still, it helps to rapidly explore and mine existing results and holds a strategic position in the management of research data.
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Affiliation(s)
- Thomas Denecker
- CEA, CNRS, Univ. Paris-Sud, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | | | | | | | | | - Pierre Poulain
- CNRS, Univ. Paris Diderot, Institut Jacques Monod (IJM), Paris, France
| | - Gaëlle Lelandais
- CEA, CNRS, Univ. Paris-Sud, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
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Pais P, Galocha M, Viana R, Cavalheiro M, Pereira D, Teixeira MC. Microevolution of the pathogenic yeasts Candida albicans and Candida glabrata during antifungal therapy and host infection. MICROBIAL CELL 2019; 6:142-159. [PMID: 30854392 PMCID: PMC6402363 DOI: 10.15698/mic2019.03.670] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Infections by the pathogenic yeasts Candida albicans and Candida glabrata are among the most common fungal diseases. The success of these species as human pathogens is contingent on their ability to resist antifungal therapy and thrive within the human host. C. glabrata is especially resilient to azole antifungal treatment, while C. albicans is best known for its wide array of virulence features. The core mechanisms that underlie antifungal resistance and virulence in these pathogens has been continuously addressed, but the investigation on how such mechanisms evolve according to each environment is scarcer. This review aims to explore current knowledge on micro-evolution experiments to several treatment and host-associated conditions in C. albicans and C. glabrata. The analysis of adaptation strategies that evolve over time will allow to better understand the mechanisms by which Candida species are able to achieve stable phenotypes in real-life scenarios, which are the ones that should constitute the most interesting drug targets.
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Affiliation(s)
- Pedro Pais
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.,iBB - Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, Lisboa, Portugal
| | - Mónica Galocha
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.,iBB - Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, Lisboa, Portugal
| | - Romeu Viana
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.,iBB - Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, Lisboa, Portugal
| | - Mafalda Cavalheiro
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.,iBB - Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, Lisboa, Portugal
| | - Diana Pereira
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.,iBB - Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, Lisboa, Portugal
| | - Miguel Cacho Teixeira
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.,iBB - Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, Lisboa, Portugal
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Huang M, Kao KC. Identifying novel genetic determinants for oxidative stress tolerance in Candida glabrata via adaptive laboratory evolution. Yeast 2018; 35:605-618. [PMID: 30141215 DOI: 10.1002/yea.3352] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/11/2018] [Accepted: 08/15/2018] [Indexed: 11/09/2022] Open
Abstract
Candida glabrata (C glabrata) is an important yeast of industrial and medical significance. Resistance to oxidative stress is an important trait affecting its robustness as a production host or virulence as a pathogenic agent, but current understanding of resistance mechanisms is still limited in this fungus. In this study, we rapidly evolved C glabrata population to adapt to oxidative challenge (from 80mM to 350mM of H2 O2 ) through short-term adaptive laboratory evolution. Adaptive mutants were isolated from evolved populations and subjected to phenotypic and omics analyses to identify potential mechanisms of tolerance to H2 O2 . Phenotypic characterizations revealed faster detoxification of H2 O2 and ability to initiate growth at a higher concentration of the oxidant in the isolated adaptive mutants compared with the wild type. Genome resequencing and genome-wide transcriptome analysis revealed multiple genetic determinants (eg, CAGL0E01243g, CAGL0F06831g, and CAGL0C00385g) that potentially contribute to enhanced H2 O2 resistance. Subsequent experimental verification confirmed that CgCth2 (CAGL0E01243g) and CgMga2 (CAGL0F06831g) are important in C glabrata tolerance to oxidative stress. Transcriptome profiling of adaptive mutants and bioinformatic analysis suggest that NADPH regeneration, modulation of membrane composition, cell wall remodeling, and/or global regulatory changes are involved in C glabrata tolerance to H2 O2 .
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Affiliation(s)
- Mian Huang
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas
| | - Katy C Kao
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas
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Vighi M, Rico A. The Concept of Resilience in Ecological Risk Assessment: Scientific and Regulatory Issues. INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT 2018; 14:581-585. [PMID: 30489028 DOI: 10.1002/ieam.4080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 04/26/2018] [Accepted: 06/18/2018] [Indexed: 06/09/2023]
Abstract
Resilience represents one of the key components of the vulnerability of ecological systems and may refer to different levels of biological organization, from populations to the biosphere. A short description is given on the concept of resilience applied to the levels that are directly involved in ecological risk assessment (ERA): populations, communities, and ecosystems. The opportunities and challenges for measuring and quantifying resilience are discussed. Finally, some suggestions for introducing the resilience concept in regulatory ERA are proposed. Integr Environ Assess Manag 2018;14:581-585. © 2018 SETAC.
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Affiliation(s)
- Marco Vighi
- IMDEA Water Institute, Science and Technology Campus of the University of Alcalá, Madrid, Spain
| | - Andreu Rico
- IMDEA Water Institute, Science and Technology Campus of the University of Alcalá, Madrid, Spain
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Identification of a polysaccharide produced by the pyruvate overproducer Candida glabrata CCTCC M202019. Appl Microbiol Biotechnol 2017; 101:4447-4458. [DOI: 10.1007/s00253-017-8245-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 03/08/2017] [Accepted: 03/12/2017] [Indexed: 12/22/2022]
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12
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Luo Z, Zeng W, Du G, Liu S, Fang F, Zhou J, Chen J. A high-throughput screening procedure for enhancing pyruvate production in Candida glabrata by random mutagenesis. Bioprocess Biosyst Eng 2017; 40:693-701. [DOI: 10.1007/s00449-017-1734-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 01/07/2017] [Indexed: 12/30/2022]
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13
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The CgHaa1-Regulon Mediates Response and Tolerance to Acetic Acid Stress in the Human Pathogen Candida glabrata. G3-GENES GENOMES GENETICS 2017; 7:1-18. [PMID: 27815348 PMCID: PMC5217100 DOI: 10.1534/g3.116.034660] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
To thrive in the acidic vaginal tract, Candida glabrata has to cope with high concentrations of acetic acid. The mechanisms underlying C. glabrata tolerance to acetic acid at low pH remain largely uncharacterized. In this work, the essential role of the CgHaa1 transcription factor (encoded by ORF CAGL0L09339g) in the response and tolerance of C. glabrata to acetic acid is demonstrated. Transcriptomic analysis showed that CgHaa1 regulates, directly or indirectly, the expression of about 75% of the genes activated under acetic acid stress. CgHaa1-activated targets are involved in multiple physiological functions including membrane transport, metabolism of carbohydrates and amino acids, regulation of the activity of the plasma membrane H+-ATPase, and adhesion. Under acetic acid stress, CgHaa1 increased the activity and the expression of the CgPma1 proton pump and contributed to increased colonization of vaginal epithelial cells by C. glabrata. CgHAA1, and two identified CgHaa1-activated targets, CgTPO3 and CgHSP30, are herein demonstrated to be determinants of C. glabrata tolerance to acetic acid. The protective effect of CgTpo3 and of CgHaa1 was linked to a role of these proteins in reducing the accumulation of acetic acid inside C. glabrata cells. In response to acetic acid stress, marked differences were found in the regulons controlled by CgHaa1 and by its S. cerevisiae ScHaa1 ortholog, demonstrating a clear divergent evolution of the two regulatory networks. The results gathered in this study significantly advance the understanding of the molecular mechanisms underlying the success of C. glabrata as a vaginal colonizer.
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Pais P, Pires C, Costa C, Okamoto M, Chibana H, Teixeira MC. Membrane Proteomics Analysis of the Candida glabrata Response to 5-Flucytosine: Unveiling the Role and Regulation of the Drug Efflux Transporters CgFlr1 and CgFlr2. Front Microbiol 2016; 7:2045. [PMID: 28066366 PMCID: PMC5174090 DOI: 10.3389/fmicb.2016.02045] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 12/06/2016] [Indexed: 11/19/2022] Open
Abstract
Resistance to 5-flucytosine (5-FC), used as an antifungal drug in combination therapy, compromises its therapeutic action. In this work, the response of the human pathogen Candida glabrata to 5-FC was evaluated at the membrane proteome level, using an iTRAQ-based approach. A total of 32 proteins were found to display significant expression changes in the membrane fraction of cells upon exposure to 5-FC, 50% of which under the control of CgPdr1, the major regulator of azole drug resistance. These proteins cluster into functional groups associated to cell wall assembly, lipid metabolism, amino acid/nucleotide metabolism, ribosome components and translation machinery, mitochondrial function, glucose metabolism, and multidrug resistance transport. Given the obtained indications, the function of the drug:H+ antiporters CgFlr1 (ORF CAGL0H06017g) and CgFlr2 (ORF CAGL0H06039g) was evaluated. The expression of both proteins, localized to the plasma membrane, was found to confer flucytosine resistance. CgFlr2 further confers azole drug resistance. The deletion of CgFLR1 or CgFLR2 was seen to increase the intracellular accumulation of 5-FC, or 5-FC and clotrimazole, suggesting that these transporters play direct roles in drug extrusion. The expression of CgFLR1 and CgFLR2 was found to be controlled by the transcription factors CgPdr1 and CgYap1, major regulator of oxidative stress resistance.
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Affiliation(s)
- Pedro Pais
- Department of Bioengineering, Instituto Superior Técnico, Universidade de LisboaLisbon, Portugal; Biological Sciences Research Group, Institute for Bioengineering and Biosciences, Instituto Superior TécnicoLisboa, Portugal
| | - Carla Pires
- Department of Bioengineering, Instituto Superior Técnico, Universidade de LisboaLisbon, Portugal; Biological Sciences Research Group, Institute for Bioengineering and Biosciences, Instituto Superior TécnicoLisboa, Portugal
| | - Catarina Costa
- Department of Bioengineering, Instituto Superior Técnico, Universidade de LisboaLisbon, Portugal; Biological Sciences Research Group, Institute for Bioengineering and Biosciences, Instituto Superior TécnicoLisboa, Portugal
| | - Michiyo Okamoto
- Medical Mycology Research Center, Chiba University Chiba, Japan
| | - Hiroji Chibana
- Medical Mycology Research Center, Chiba University Chiba, Japan
| | - Miguel C Teixeira
- Department of Bioengineering, Instituto Superior Técnico, Universidade de LisboaLisbon, Portugal; Biological Sciences Research Group, Institute for Bioengineering and Biosciences, Instituto Superior TécnicoLisboa, Portugal
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15
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Thompson DA, Cubillos FA. Natural gene expression variation studies in yeast. Yeast 2016; 34:3-17. [PMID: 27668700 DOI: 10.1002/yea.3210] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 09/16/2016] [Accepted: 09/18/2016] [Indexed: 11/06/2022] Open
Abstract
The rise of sequence information across different yeast species and strains is driving an increasing number of studies in the emerging field of genomics to associate polymorphic variants, mRNA abundance and phenotypic differences between individuals. Here, we gathered evidence from recent studies covering several layers that define the genotype-phenotype gap, such as mRNA abundance, allele-specific expression and translation efficiency to demonstrate how genetic variants co-evolve and define an individual's genome. Moreover, we exposed several antecedents where inter- and intra-specific studies led to opposite conclusions, probably owing to genetic divergence. Future studies in this area will benefit from the access to a massive array of well-annotated genomes and new sequencing technologies, which will allow the fine breakdown of the complex layers that delineate the genotype-phenotype map. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
| | - Francisco A Cubillos
- Centro de Estudios en Ciencia y Tecnología de Alimentos, Universidad de Santiago de Chile, Santiago, Chile.,Millennium Nucleus for Fungal Integrative and Synthetic Biology.,Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
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16
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Merhej J, Thiebaut A, Blugeon C, Pouch J, Ali Chaouche MEA, Camadro JM, Le Crom S, Lelandais G, Devaux F. A Network of Paralogous Stress Response Transcription Factors in the Human Pathogen Candida glabrata. Front Microbiol 2016; 7:645. [PMID: 27242683 PMCID: PMC4860858 DOI: 10.3389/fmicb.2016.00645] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Accepted: 04/18/2016] [Indexed: 01/15/2023] Open
Abstract
The yeast Candida glabrata has become the second cause of systemic candidemia in humans. However, relatively few genome-wide studies have been conducted in this organism and our knowledge of its transcriptional regulatory network is quite limited. In the present work, we combined genome-wide chromatin immunoprecipitation (ChIP-seq), transcriptome analyses, and DNA binding motif predictions to describe the regulatory interactions of the seven Yap (Yeast AP1) transcription factors of C. glabrata. We described a transcriptional network containing 255 regulatory interactions and 309 potential target genes. We predicted with high confidence the preferred DNA binding sites for 5 of the 7 CgYaps and showed a strong conservation of the Yap DNA binding properties between S. cerevisiae and C. glabrata. We provided reliable functional annotation for 3 of the 7 Yaps and identified for Yap1 and Yap5 a core regulon which is conserved in S. cerevisiae, C. glabrata, and C. albicans. We uncovered new roles for CgYap7 in the regulation of iron-sulfur cluster biogenesis, for CgYap1 in the regulation of heme biosynthesis and for CgYap5 in the repression of GRX4 in response to iron starvation. These transcription factors define an interconnected transcriptional network at the cross-roads between redox homeostasis, oxygen consumption, and iron metabolism.
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Affiliation(s)
- Jawad Merhej
- Laboratoire de Biologie Computationnelle et Quantitative, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, UMR 7238, Sorbonne Universités, Université Pierre et Marie Curie Paris, France
| | - Antonin Thiebaut
- Laboratoire de Biologie Computationnelle et Quantitative, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, UMR 7238, Sorbonne Universités, Université Pierre et Marie Curie Paris, France
| | - Corinne Blugeon
- École Normale Supérieure, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut de Biologie de l'École Normale Supérieure, Plateforme Génomique Paris, France
| | - Juliette Pouch
- École Normale Supérieure, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut de Biologie de l'École Normale Supérieure, Plateforme Génomique Paris, France
| | - Mohammed El Amine Ali Chaouche
- École Normale Supérieure, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut de Biologie de l'École Normale Supérieure, Plateforme Génomique Paris, France
| | - Jean-Michel Camadro
- Centre National de la Recherche Scientifique, UMR 7592, Institut Jacques Monod, Université Paris Diderot, Sorbonne Paris Cité Paris, France
| | - Stéphane Le Crom
- Évolution, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, UMR 7138, Sorbonne Universités, Université Pierre et Marie Curie Paris, France
| | - Gaëlle Lelandais
- Centre National de la Recherche Scientifique, UMR 7592, Institut Jacques Monod, Université Paris Diderot, Sorbonne Paris Cité Paris, France
| | - Frédéric Devaux
- Laboratoire de Biologie Computationnelle et Quantitative, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, UMR 7238, Sorbonne Universités, Université Pierre et Marie Curie Paris, France
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17
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Roy S, Thompson D. Evolution of regulatory networks in Candida glabrata: learning to live with the human host. FEMS Yeast Res 2015; 15:fov087. [PMID: 26449820 DOI: 10.1093/femsyr/fov087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2015] [Indexed: 12/12/2022] Open
Abstract
The opportunistic human fungal pathogen Candida glabrata is second only to C. albicans as the cause of Candida infections and yet is more closely related to Saccharomyces cerevisiae. Recent advances in functional genomics technologies and computational approaches to decipher regulatory networks, and the comparison of these networks among these and other Ascomycete species, have revealed both unique and shared strategies in adaptation to a human commensal/opportunistic pathogen lifestyle and antifungal drug resistance in C. glabrata. Recently, several C. glabrata sister species in the Nakeseomyces clade representing both human associated (commensal) and environmental isolates have had their genomes sequenced and analyzed. This has paved the way for comparative functional genomics studies to characterize the regulatory networks in these species to identify informative patterns of conservation and divergence linked to phenotypic evolution in the Nakaseomyces lineage.
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Affiliation(s)
- Sushmita Roy
- Department of Biostatistics and Medical Informatics, University of Wisconsin Madison, Madison, WI 53715, USA Wisconsin Institute for Discovery, University of Wisconsin, Madison, WI 53715, USA
| | - Dawn Thompson
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
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18
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Braconi D, Bernardini G, Santucci A. Saccharomyces cerevisiae as a model in ecotoxicological studies: A post-genomics perspective. J Proteomics 2015; 137:19-34. [PMID: 26365628 DOI: 10.1016/j.jprot.2015.09.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 08/29/2015] [Accepted: 09/02/2015] [Indexed: 12/13/2022]
Abstract
The budding yeast Saccharomyces cerevisiae represents a well-consolidated and widely used eukaryotic model, with a number of features that make it an ideal organism to carry out functional toxicological studies. Several advantages are permitted by the use of yeast cells, as the possibility to identify molecular biomarkers, unknown mechanisms of action and novel potential targets. Thanks to the evolutionary conservation, yeast can provide also useful clues allowing the prioritization of more complex analyses and toxicity predictions in higher eukaryotes. The last two decades were incredibly fruitful for yeast "omics", but referring to the analysis of the effects of pesticides on yeast much still remains to be done. Furthermore, a deeper knowledge of the effects of environmental pollutants on biotechnological processes associated with the use of yeasts is to be hoped.
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Affiliation(s)
- Daniela Braconi
- Dipartimento di Biotecnologie, Chimica e Farmacia, via A. Moro 2, Università degli Studi di Siena, 53100 Siena, Italy
| | - Giulia Bernardini
- Dipartimento di Biotecnologie, Chimica e Farmacia, via A. Moro 2, Università degli Studi di Siena, 53100 Siena, Italy
| | - Annalisa Santucci
- Dipartimento di Biotecnologie, Chimica e Farmacia, via A. Moro 2, Università degli Studi di Siena, 53100 Siena, Italy.
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19
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Corso M, Vannozzi A, Maza E, Vitulo N, Meggio F, Pitacco A, Telatin A, D'Angelo M, Feltrin E, Negri AS, Prinsi B, Valle G, Ramina A, Bouzayen M, Bonghi C, Lucchin M. Comprehensive transcript profiling of two grapevine rootstock genotypes contrasting in drought susceptibility links the phenylpropanoid pathway to enhanced tolerance. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:5739-52. [PMID: 26038306 PMCID: PMC4566973 DOI: 10.1093/jxb/erv274] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In light of ongoing climate changes in wine-growing regions, the selection of drought-tolerant rootstocks is becoming a crucial factor for developing a sustainable viticulture. In this study, M4, a new rootstock genotype that shows tolerance to drought, was compared from a genomic and transcriptomic point of view with the less drought-tolerant genotype 101.14. The root and leaf transcriptome of both 101.14 and the M4 rootstock genotype was analysed, following exposure to progressive drought conditions. Multifactorial analyses indicated that stress treatment represents the main factor driving differential gene expression in roots, whereas in leaves the genotype is the prominent factor. Upon stress, M4 roots and leaves showed a higher induction of resveratrol and flavonoid biosynthetic genes, respectively. The higher expression of VvSTS genes in M4, confirmed by the accumulation of higher levels of resveratrol in M4 roots compared with 101.14, was coupled to an up-regulation of several VvWRKY transcription factors. Interestingly, VvSTS promoter analyses performed on both the resequenced genomes highlighted a significantly higher number of W-BOX elements in the tolerant genotype. It is proposed that the elevated synthesis of resveratrol in M4 roots upon water stress could enhance the plant's ability to cope with the oxidative stress usually associated with water deficit.
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Affiliation(s)
- Massimiliano Corso
- Department of Agronomy, Food, Natural resources, Animals and Environment (DAFNAE), University of Padova Agripolis, 35020 Legnaro, Italy Centro Interdipartimentale per la Ricerca in Viticoltura ed Enologia (CIRVE), Via XXVIII Aprile, 14-31015 Conegliano (TV), Italy
| | - Alessandro Vannozzi
- Department of Agronomy, Food, Natural resources, Animals and Environment (DAFNAE), University of Padova Agripolis, 35020 Legnaro, Italy Centro Interdipartimentale per la Ricerca in Viticoltura ed Enologia (CIRVE), Via XXVIII Aprile, 14-31015 Conegliano (TV), Italy
| | - Elie Maza
- Genomics and Biotechnology of Fruit (GBF) Laboratory, Institut National Polytechnique de Toulouse, Avenue de l'Agrobiopole, F-31326 Castanet-Tolosan Cedex (Toulouse), France
| | - Nicola Vitulo
- CRIBI, University of Padova, viale G. Colombo 3, 35121 Padova, Italy
| | - Franco Meggio
- Department of Agronomy, Food, Natural resources, Animals and Environment (DAFNAE), University of Padova Agripolis, 35020 Legnaro, Italy Centro Interdipartimentale per la Ricerca in Viticoltura ed Enologia (CIRVE), Via XXVIII Aprile, 14-31015 Conegliano (TV), Italy
| | - Andrea Pitacco
- Department of Agronomy, Food, Natural resources, Animals and Environment (DAFNAE), University of Padova Agripolis, 35020 Legnaro, Italy Centro Interdipartimentale per la Ricerca in Viticoltura ed Enologia (CIRVE), Via XXVIII Aprile, 14-31015 Conegliano (TV), Italy
| | - Andrea Telatin
- CRIBI, University of Padova, viale G. Colombo 3, 35121 Padova, Italy
| | - Michela D'Angelo
- CRIBI, University of Padova, viale G. Colombo 3, 35121 Padova, Italy
| | - Erika Feltrin
- CRIBI, University of Padova, viale G. Colombo 3, 35121 Padova, Italy
| | - Alfredo Simone Negri
- Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy (DiSAA), University of Milano, Milano 20133, Italy
| | - Bhakti Prinsi
- Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy (DiSAA), University of Milano, Milano 20133, Italy
| | - Giorgio Valle
- CRIBI, University of Padova, viale G. Colombo 3, 35121 Padova, Italy
| | - Angelo Ramina
- Department of Agronomy, Food, Natural resources, Animals and Environment (DAFNAE), University of Padova Agripolis, 35020 Legnaro, Italy Centro Interdipartimentale per la Ricerca in Viticoltura ed Enologia (CIRVE), Via XXVIII Aprile, 14-31015 Conegliano (TV), Italy
| | - Mondher Bouzayen
- Genomics and Biotechnology of Fruit (GBF) Laboratory, Institut National Polytechnique de Toulouse, Avenue de l'Agrobiopole, F-31326 Castanet-Tolosan Cedex (Toulouse), France
| | - Claudio Bonghi
- Department of Agronomy, Food, Natural resources, Animals and Environment (DAFNAE), University of Padova Agripolis, 35020 Legnaro, Italy Centro Interdipartimentale per la Ricerca in Viticoltura ed Enologia (CIRVE), Via XXVIII Aprile, 14-31015 Conegliano (TV), Italy
| | - Margherita Lucchin
- Department of Agronomy, Food, Natural resources, Animals and Environment (DAFNAE), University of Padova Agripolis, 35020 Legnaro, Italy Centro Interdipartimentale per la Ricerca in Viticoltura ed Enologia (CIRVE), Via XXVIII Aprile, 14-31015 Conegliano (TV), Italy
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20
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Culakova H, Dzugasova V, Valencikova R, Gbelska Y, Subik J. Stress response and expression of fluconazole resistance associated genes in the pathogenic yeast Candida glabrata deleted in the CgPDR16 gene. Microbiol Res 2015; 174:17-23. [PMID: 25946325 DOI: 10.1016/j.micres.2015.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 02/26/2015] [Accepted: 03/03/2015] [Indexed: 12/27/2022]
Abstract
In yeasts, the PDR16 gene encodes a phosphatidylinositol transfer protein which belongs to the Sec14 homologue (SFH) family and localizes to lipid droplets, microsomes and at the cell periphery. The loss of its function alters the lipid droplet metabolism and plasma membrane properties, and renders yeast cells more sensitive to azole antimycotics. In this study, the entire chromosomal CgPDR16 ORF was replaced by the ScURA3 gene both in azole sensitive and azole resistant strains of Candida glabrata bearing a gain-of-function mutation in the CgPDR1 gene, and their responses to different stresses were assessed. The CgPDR16 deletion was found to sensitize the mutant strains to azole antifungals without changes in their osmo- and halotolerance. Fluconazole treated pdr16Δ mutant strains displayed a reduced expression of several genes involved in azole tolerance. The gain-of-function CgPDR1 allele as well as the cycloheximide and hydrogen peroxide treatments of cells enhanced the expression of the CgPDR16 gene. The results indicate that CgPDR16 belongs to genes whose expression is induced by chemical and oxidative stresses. The loss of its function can attenuate the expression of drug efflux pump encoding genes that might also contribute to the decreased azole tolerance in pdr16Δ mutant cells.
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Affiliation(s)
- Hana Culakova
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University in Bratislava, 842 15 Bratislava, Slovak Republic
| | - Vladimira Dzugasova
- Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, 842 15 Bratislava, Slovak Republic
| | - Romana Valencikova
- Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, 842 15 Bratislava, Slovak Republic
| | - Yvetta Gbelska
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University in Bratislava, 842 15 Bratislava, Slovak Republic
| | - Julius Subik
- Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, 842 15 Bratislava, Slovak Republic.
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21
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Merhej J, Frigo A, Le Crom S, Camadro JM, Devaux F, Lelandais G. bPeaks: a bioinformatics tool to detect transcription factor binding sites from ChIPseq data in yeasts and other organisms with small genomes. Yeast 2014; 31:375-91. [PMID: 25041923 DOI: 10.1002/yea.3031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 07/03/2014] [Accepted: 07/03/2014] [Indexed: 01/04/2023] Open
Abstract
Peak calling is a critical step in ChIPseq data analysis. Choosing the correct algorithm as well as optimized parameters for a specific biological system is an essential task. In this article, we present an original peak-calling method (bPeaks) specifically designed to detect transcription factor (TF) binding sites in small eukaryotic genomes, such as in yeasts. As TF interactions with DNA are strong and generate high binding signals, bPeaks uses simple parameters to compare the sequences (reads) obtained from the immunoprecipitation (IP) with those from the control DNA (input). Because yeasts have small genomes (<20 Mb), our program has the advantage of using ChIPseq information at the single nucleotide level and can explore, in a reasonable computational time, results obtained with different sets of parameter values. Graphical outputs and text files are provided to rapidly assess the relevance of the detected peaks. Taking advantage of the simple promoter structure in yeasts, additional functions were implemented in bPeaks to automatically assign the peaks to promoter regions and retrieve peak coordinates on the DNA sequence for further predictions of regulatory motifs, enriched in the list of peaks. Applications of the bPeaks program to three different ChIPseq datasets from Saccharomyces cerevisiae, Candida albicans and Candida glabrata are presented. Each time, bPeaks allowed us to correctly predict the DNA binding sequence of the studied TF and provided relevant lists of peaks. The bioinformatics tool bPeaks is freely distributed to academic users. Supplementary data, together with detailed tutorials, are available online: http://bpeaks.gene-networks.net.
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Affiliation(s)
- Jawad Merhej
- Sorbonne Universités, UPMC University of Paris 06, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France; CNRS, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
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22
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Improvement of oxidative stress tolerance in Saccharomyces cerevisiae through global transcription machinery engineering. J Ind Microbiol Biotechnol 2014; 41:869-78. [PMID: 24633583 DOI: 10.1007/s10295-014-1421-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 02/12/2014] [Indexed: 01/21/2023]
Abstract
Excessive oxidative stress poses significant damage to yeast cells during fermentation process, and finally affects fermentation efficiency and the quality of products. In this paper, global transcription machinery engineering was employed to elicit Saccharomyces cerevisiae phenotypes of higher tolerance against oxidative stress caused by H2O2. Two strains from two plasmid-based mutagenesis libraries (Spt15 and Taf25), which exhibited significant increases in oxidative stress tolerance, were successfully isolated. At moderate H2O2 shock (≤3.5 mM), a positive correlation was found between the outperformance in cell growth of the oxidation-tolerate strains and H2O2 concentration. Several mutations were observed in the native transcription factors, which resulted in a different transcriptional profile compared with the control. Catalase and superoxide dismutase activities of the two mutants increased under H2O2 stress conditions. Fermentation experiments revealed that the mutant strain taf25-3 has a shorter lag phase compared to the control one, indicating that taf25-3 had improved adaptation ability to H2O2-induced oxidative stress and higher fermentation efficiency. Our study demonstrated that several amino acid substitutions in general transcription factors (Spt15 and Taf25) could modify the cellular oxidation defense systems and improve the anti-oxidation ability of S. cerevisiae. It could make the industrial ethanol fermentation more efficient and cost-effective by using the strain of higher stress tolerance.
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23
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Culakova H, Dzugasova V, Perzelova J, Gbelska Y, Subik J. Mutation of the CgPDR16 gene attenuates azole tolerance and biofilm production in pathogenic Candida glabrata. Yeast 2013; 30:403-14. [PMID: 23939632 DOI: 10.1002/yea.2978] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 07/23/2013] [Accepted: 08/07/2013] [Indexed: 01/26/2023] Open
Abstract
The PDR16 gene encodes the homologue of Sec14p, participating in protein secretion, regulation of lipid synthesis and turnover in vivo and acting as a phosphatidylinositol transfer protein in vitro. This gene is also involved in the regulation of multidrug resistance in Saccharomyces cerevisiae and pathogenic yeasts. Here we report the results of functional analysis of the CgPDR16 gene, whose mutation has been previously shown to enhance fluconazole sensitivity in Candida glabrata mutant cells. We have cloned the CgPDR16 gene, which was able to complement the pdr16Δ mutation in both C. glabrata and S. cerevisiae. Along with fluconazole, the pdr16Δ mutation resulted in increased susceptibility of mutant cells to several azole antifungals without changes in sensitivity to polyene antibiotics, cycloheximide, NQO, 5-fluorocytosine and oxidants inducing the intracellular formation of reactive oxygen species. The susceptibility of the pdr16Δ mutant strain to itraconazole and 5-fluorocytosine was enhanced by CTBT [7-chlorotetrazolo(5,1-c)benzo(1,2,4)triazine] inducing oxidative stress. The pdr16Δ mutation increased the accumulation of rhodamine 6G in mutant cells, decreased the level of itraconazole resistance caused by gain-of-function mutations in the CgPDR1 gene, and reduced cell surface hydrophobicity and biofilm production. These results point to the pleiotropic phenotype of the pdr16Δ mutant and support the role of the CgPDR16 gene in the control of drug susceptibility and virulence in the pathogenic C. glabrata.
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Affiliation(s)
- Hana Culakova
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University in Bratislava, 842 15, Bratislava, Slovak Republic
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24
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Thompson DA, Roy S, Chan M, Styczynsky MP, Pfiffner J, French C, Socha A, Thielke A, Napolitano S, Muller P, Kellis M, Konieczka JH, Wapinski I, Regev A. Evolutionary principles of modular gene regulation in yeasts. eLife 2013; 2:e00603. [PMID: 23795289 PMCID: PMC3687341 DOI: 10.7554/elife.00603] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 05/02/2013] [Indexed: 12/20/2022] Open
Abstract
Divergence in gene regulation can play a major role in evolution. Here, we used a phylogenetic framework to measure mRNA profiles in 15 yeast species from the phylum Ascomycota and reconstruct the evolution of their modular regulatory programs along a time course of growth on glucose over 300 million years. We found that modules have diverged proportionally to phylogenetic distance, with prominent changes in gene regulation accompanying changes in lifestyle and ploidy, especially in carbon metabolism. Paralogs have significantly contributed to regulatory divergence, typically within a very short window from their duplication. Paralogs from a whole genome duplication (WGD) event have a uniquely substantial contribution that extends over a longer span. Similar patterns occur when considering the evolution of the heat shock regulatory program measured in eight of the species, suggesting that these are general evolutionary principles. DOI:http://dx.doi.org/10.7554/eLife.00603.001 The incredible diversity of living creatures belies the fact that their genes are quite similar. In the 1970s Mary-Claire King and Allan Wilson proposed that a process called gene regulation—which determines when, where and how genes are expressed as proteins—is responsible for this diversity. Four decades later, the central role of gene regulation in evolution has been confirmed in a wide range of species including bacteria, fungi, flies and mammals, although the details remain poorly understood. In recent years it has been suggested that the duplication of genes—and sometimes the duplication of whole genomes—has had a crucial influence on the part played by gene regulation in the evolution of many different species. Ascomycota fungi are uniquely suited to the study of genetics and evolution because of their diversity—they include C. albicans, a fungus that is found in the human mouth and gut, and various species of yeast—and because many of their genomes have already been sequenced. Moreover, their genomes are relatively small, which simplifies the task of working out how it has changed over the course of evolution. It is also known that species in this branch of the tree of life diverged before and after an event in which a whole genome was duplicated. Ascomycota fungi use glucose as a source of carbon in different ways during aerobic growth. Most, including C. albicans, are respiratory and rely on oxidative phosphorylation processes to produce energy. However, a small number—including S. cerevisiae and S. pombe, two types of yeast that are widely used as model organisms—prefer to ferment glucose, even when oxygen is available. Species that favor the latter respiro-fermentative lifestyle have evolved independently at least twice: once after the whole genome duplication event that lead to S. cerevisiae, and once when S. pombe and the other fission yeasts evolved. Thompson et al. have measured mRNA profiles in 15 different species of yeast and reconstructed how the regulation of groups of genes (modules) have evolved over a period of more than 300 million years. They found that modules have diverged proportionally to evolutionary time, with prominent changes in gene regulation being associated with changes in lifestyle (especially changes in carbon metabolism) and a whole genome duplication event. Gene duplication events result in gene paralogs—identical genes at different places in the genome—and these have made significant contributions to the evolution of different forms of gene regulation, especially just after the duplication event. Moreover, the paralogs produced in whole genome duplication events have resulted in bigger changes over longer periods of time. Similar patterns were observed in the regulation of the genes involved in the response to heat shock in eight of the species, which suggests that these are general evolutionary principles. The changes in gene expression associated with the respiro-fermentative lifestyle may also have implications for our understanding of cancer: healthy cells rely on oxidative phosphorylation to produce energy whereas, similar to yeast cells, most cancerous cells rely on respiro-fermentation. Furthermore, yeast cells and cancer cells both support their rapid growth and proliferation by using glucose for biosynthesis to support cell division, although this process is not fully understood. Normal cells, on the other hand, use glucose primarily for energy and tend not to divide rapidly. Thompson et al. found that the genes encoding enzymes in two biosynthetic pathways—one that produces the nucleotides necessary for DNA replication, and one that synthesizes glycine—are induced in respiro-fermentative yeasts but repressed in respiratory yeast cells. The fact that similar changes are observed in the same two pathways when normal cells become cancer cells suggests that these pathways have an important role in the development of cancer. The framework developed by Thompson et al. could also be used to explore the evolution of gene regulation in other species and biological processes. DOI:http://dx.doi.org/10.7554/eLife.00603.002
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Affiliation(s)
- Dawn A Thompson
- Broad Institute of MIT and Harvard , Cambridge , United States
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25
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Rossignol T, Kocsis B, Bouquet O, Kustos I, Kilár F, Nyul A, Jakus PB, Rajbhandari K, Prókai L, d’Enfert C, Lóránd T. Antifungal activity of fused Mannich ketones triggers an oxidative stress response and is Cap1-dependent in Candida albicans. PLoS One 2013; 8:e62142. [PMID: 23646117 PMCID: PMC3639977 DOI: 10.1371/journal.pone.0062142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 03/18/2013] [Indexed: 01/02/2023] Open
Abstract
We investigated the antifungal activity of fused Mannich ketone (FMK) congeners and two of their aminoalcohol derivatives. In particular, FMKs with five-membered saturated rings were shown to have minimum inhibitory concentration (MIC90s) ranging from 0.8 to 6 µg/mL toward C. albicans and the closely related C. parapsilosis and C. krusei while having reduced efficacy toward C. glabrata and almost no efficacy against Aspergillus sp. Transcript profiling of C. albicans cells exposed for 30 or 60 min to 2-(morpholinomethyl)-1-indanone, a representative FMK with a five-membered saturated ring, revealed a transcriptional response typical of oxidative stress and similar to that of a C. albicans Cap1 transcriptional activator. Consistently, C. albicans lacking the CAP1 gene was hypersensitive to this FMK, while C. albicans strains overexpressing CAP1 had decreased sensitivity to 2-(morpholinomethyl)-1-indanone. Quantitative structure-activity relationship studies revealed a correlation of antifungal potency and the energy of the lowest unoccupied molecular orbital of FMKs and unsaturated Mannich ketones thereby implicating redox cycling-mediated oxidative stress as a mechanism of action. This conclusion was further supported by the loss of antifungal activity upon conversion of representative FMKs to aminoalcohols that were unable to participate in redox cycles.
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Affiliation(s)
- Tristan Rossignol
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC 2019, Paris, France
| | - Béla Kocsis
- Department of Medical Microbiology and Immunology, Faculty of Medicine, University of Pécs, Pécs, Hungary
| | - Orsolya Bouquet
- Institute of Bioanalysis, Faculty of Medicine, University of Pécs, Pécs, Hungary
| | - Ildikó Kustos
- Department of Microbiology, Alder Hey Children`s NHS Foundation Trust, Liverpool, United Kingdom
| | - Ferenc Kilár
- Institute of Bioanalysis, Faculty of Medicine, University of Pécs, Pécs, Hungary
| | - Adrien Nyul
- Department of Medical Microbiology and Immunology, Faculty of Medicine, University of Pécs, Pécs, Hungary
| | - Péter B. Jakus
- Department of Biochemistry and Medical Chemistry, Faculty of Medicine, University of Pécs, Pécs, Hungary
| | - Kshitij Rajbhandari
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, Texas, United States of America
| | - László Prókai
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, Texas, United States of America
| | - Christophe d’Enfert
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC 2019, Paris, France
| | - Tamás Lóránd
- Department of Biochemistry and Medical Chemistry, Faculty of Medicine, University of Pécs, Pécs, Hungary
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Comparative gene expression between two yeast species. BMC Genomics 2013; 14:33. [PMID: 23324262 PMCID: PMC3556494 DOI: 10.1186/1471-2164-14-33] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 01/03/2013] [Indexed: 02/07/2023] Open
Abstract
Background Comparative genomics brings insight into sequence evolution, but even more may be learned by coupling sequence analyses with experimental tests of gene function and regulation. However, the reliability of such comparisons is often limited by biased sampling of expression conditions and incomplete knowledge of gene functions across species. To address these challenges, we previously systematically generated expression profiles in Saccharomyces bayanus to maximize functional coverage as compared to an existing Saccharomyces cerevisiae data repository. Results In this paper, we take advantage of these two data repositories to compare patterns of ortholog expression in a wide variety of conditions. First, we developed a scalable metric for expression divergence that enabled us to detect a significant correlation between sequence and expression conservation on the global level, which previous smaller-scale expression studies failed to detect. Despite this global conservation trend, between-species gene expression neighborhoods were less well-conserved than within-species comparisons across different environmental perturbations, and approximately 4% of orthologs exhibited a significant change in co-expression partners. Furthermore, our analysis of matched perturbations collected in both species (such as diauxic shift and cell cycle synchrony) demonstrated that approximately a quarter of orthologs exhibit condition-specific expression pattern differences. Conclusions Taken together, these analyses provide a global view of gene expression patterns between two species, both in terms of the conditions and timing of a gene's expression as well as co-expression partners. Our results provide testable hypotheses that will direct future experiments to determine how these changes may be specified in the genome.
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Abstract
Existing antifungal agents are still confronted to activities limited to specific fungal species and to the development of resistance. Several improvements are possible either by tackling and overcoming resistance or exacerbating the activity of existing antifungal agents. In Candida glabrata, azole resistance is almost exclusively mediated by ABC transporters (including C. glabrata CDR1 [CgCDR1] and CgCDR2) via gain-of-function mutations in the transcriptional activator CgPDR1 or by mitochondrial dysfunctions. We also observed that azole resistance was correlating with increasing virulence and fitness of C. glabrata in animal models of infection. This observation motivated the re-exploitation of ABC transporter inhibitors as a possible therapeutic intervention to decrease not only the development of azole resistance but also to interfere with the virulence of C. glabrata. Milbemycins are known ABC transporter inhibitors, and here we used commercially available milbemycin A3/A4 oxim derivatives to verify this effect. As expected, the derivatives were inhibiting C. glabrata efflux with the highest activity for A3 oxim below 1 μg/ml. More surprising was that oxim derivatives had intrinsic fungicidal activity above 3.2 μg/ml, thus highlighting effects additional to the efflux inhibition. Similar values were obtained with C. albicans. Our data show that the fungicidal activity could be related to reactive oxygen species formation in these species. Transcriptional analysis performed both in C. glabrata and C. albicans exposed to A3 oxim highlighted a core of commonly regulated genes involved in stress responses, including genes involved in oxidoreductive processes, protein ubiquitination, and vesicle trafficking, as well as mitogen-activated protein kinases. However, the transcript profiles contained also species-specific signatures. Following these observations, experimental treatments of invasive infections were performed in mice treated with the commercial A3/A4 oxim preparation alone or in combination with fluconazole. Tissue burden analysis revealed that oxims on their own were able to decrease fungal burdens in both Candida species. In azole-resistant isolates, oxims acted synergistically in vivo with fluconazole to reduce fungal burden to levels of azole-susceptible isolates. In conclusion, we show here the potential of milbemycins not only as drug efflux inhibitors but also as effective fungal growth inhibitors in C. glabrata and C. albicans.
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Engle EK, Fay JC. Divergence of the yeast transcription factor FZF1 affects sulfite resistance. PLoS Genet 2012; 8:e1002763. [PMID: 22719269 PMCID: PMC3375221 DOI: 10.1371/journal.pgen.1002763] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 04/26/2012] [Indexed: 01/06/2023] Open
Abstract
Changes in gene expression are commonly observed during evolution. However, the phenotypic consequences of expression divergence are frequently unknown and difficult to measure. Transcriptional regulators provide a mechanism by which phenotypic divergence can occur through multiple, coordinated changes in gene expression during development or in response to environmental changes. Yet, some changes in transcriptional regulators may be constrained by their pleiotropic effects on gene expression. Here, we use a genome-wide screen for promoters that are likely to have diverged in function and identify a yeast transcription factor, FZF1, that has evolved substantial differences in its ability to confer resistance to sulfites. Chimeric alleles from four Saccharomyces species show that divergence in FZF1 activity is due to changes in both its coding and upstream noncoding sequence. Between the two closest species, noncoding changes affect the expression of FZF1, whereas coding changes affect the expression of SSU1, a sulfite efflux pump activated by FZF1. Both coding and noncoding changes also affect the expression of many other genes. Our results show how divergence in the coding and promoter region of a transcription factor alters the response to an environmental stress. Changes in gene regulation are thought to play an important role in evolution. While variation in gene expression between species is common, it is hard to identify the phenotypic consequences of this variation since many changes in gene expression may have subtle or no phenotypic effects. In this study, we investigate changes in sulfite resistance and gene expression caused by the transcription factor, FZF1, that has evolved rapidly during the divergence of related yeast species. We find that divergence in the ability of FZF1 to confer sulfite resistance is mediated by changes in its expression as well as changes in its protein structure, both of which cause changes in the expression of other genes. Our results show how the combination of multiple changes within a transcription factor can produce substantial changes in phenotype and the expression of many genes.
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Affiliation(s)
- Elizabeth K. Engle
- Molecular Genetics and Genomics Program, Washington University, St. Louis, Missouri, United States of America
| | - Justin C. Fay
- Department of Genetics and Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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Extensive divergence of yeast stress responses through transitions between induced and constitutive activation. Proc Natl Acad Sci U S A 2011; 108:16693-8. [PMID: 21930916 DOI: 10.1073/pnas.1113718108] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Closely related species show a high degree of differences in gene expression, but the functional significance of these differences remains unclear. Similarly, stress responses in yeast typically involve differential expression of numerous genes, and it is unclear how many of these are functionally significant. To address these issues, we compared the expression programs of four yeast species under different growth conditions, and found that the response of these species to stress has diverged extensively. On an individual gene basis, most transcriptional responses are not conserved in any pair of species, and there are very limited common responses among all four species. We present evidence that many evolutionary changes in stress responses are compensated either (i) by the response of related genes or (ii) by changes in the basal expression levels of the genes whose responses have diverged. Thus, stress-related genes are often induced upon stress in some species but maintain high levels even in the absence of stress at other species, indicating a transition between induced and constitutive activation. In addition, ~15% of the stress responses are specific to only one of the four species, with no evidence for compensating effects or stress-related annotations, and these may reflect fortuitous regulation that is unimportant for the stress response (i.e., biological noise). Frequent compensatory changes and biological noise may explain how diverged expression responses support similar physiological responses.
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Lelandais G, Goudot C, Devaux F. The evolution of gene expression regulatory networks in yeasts. C R Biol 2011; 334:655-61. [PMID: 21819947 DOI: 10.1016/j.crvi.2011.05.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Accepted: 03/02/2011] [Indexed: 12/20/2022]
Abstract
Gene regulation is a major source of phenotypic diversity between and within species. This aspect of evolution has long been addressed from the sole point of view of the genome sequence. The incredible development of transcriptomics approaches now allows one to actually study the topology and the properties of regulatory networks on an evolutionary perspective. This new discipline is called comparative functional genomics or comparative transcriptomics. This article reviews some of the main advances made in this field, using yeast species, and especially the species sequenced in the frame of the Genolevures program, as a model.
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Affiliation(s)
- Gaëlle Lelandais
- Inserm UMR-S 665, Dynamique des Structures et Interactions des Macromolécules Biologiques, Université Paris Diderot, Sorbonne Paris Cité, INTS, 6 rue Alexandre-Cabanel, 75015 Paris, France.
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Goudot C, Etchebest C, Devaux F, Lelandais G. The reconstruction of condition-specific transcriptional modules provides new insights in the evolution of yeast AP-1 proteins. PLoS One 2011; 6:e20924. [PMID: 21695268 PMCID: PMC3111461 DOI: 10.1371/journal.pone.0020924] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 05/15/2011] [Indexed: 11/19/2022] Open
Abstract
AP-1 proteins are transcription factors (TFs) that belong to the basic leucine zipper family, one of the largest families of TFs in eukaryotic cells. Despite high homology between their DNA binding domains, these proteins are able to recognize diverse DNA motifs. In yeasts, these motifs are referred as YRE (Yap Response Element) and are either seven (YRE-Overlap) or eight (YRE-Adjacent) base pair long. It has been proposed that the AP-1 DNA binding motif preference relies on a single change in the amino acid sequence of the yeast AP-1 TFs (an arginine in the YRE-O binding factors being replaced by a lysine in the YRE-A binding Yaps). We developed a computational approach to infer condition-specific transcriptional modules associated to the orthologous AP-1 protein Yap1p, Cgap1p and Cap1p, in three yeast species: the model yeast Saccharomyces cerevisiae and two pathogenic species Candida glabrata and Candida albicans. Exploitation of these modules in terms of predictions of the protein/DNA regulatory interactions changed our vision of AP-1 protein evolution. Cis-regulatory motif analyses revealed the presence of a conserved adenine in 5' position of the canonical YRE sites. While Yap1p, Cgap1p and Cap1p shared a remarkably low number of target genes, an impressive conservation was observed in the YRE sequences identified by Yap1p and Cap1p. In Candida glabrata, we found that Cgap1p, unlike Yap1p and Cap1p, recognizes YRE-O and YRE-A motifs. These findings were supported by structural data available for the transcription factor Pap1p (Schizosaccharomyces pombe). Thus, whereas arginine and lysine substitutions in Cgap1p and Yap1p proteins were reported as responsible for a specific YRE-O or YRE-A preference, our analyses rather suggest that the ancestral yeast AP-1 protein could recognize both YRE-O and YRE-A motifs and that the arginine/lysine exchange is not the only determinant of the specialization of modern Yaps for one motif or another.
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Affiliation(s)
- Christel Goudot
- Dynamique des Structures et Interactions des Macromolécules Biologiques (DSIMB), INSERM, U665, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, UMR-S665, Paris, France
- INTS, Paris, France
| | - Catherine Etchebest
- Dynamique des Structures et Interactions des Macromolécules Biologiques (DSIMB), INSERM, U665, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, UMR-S665, Paris, France
- INTS, Paris, France
| | - Frédéric Devaux
- Laboratoire de Génomique des Microorganismes, UMR7238 CNRS, Université Pierre et Marie Curie, Paris, France
| | - Gaëlle Lelandais
- Dynamique des Structures et Interactions des Macromolécules Biologiques (DSIMB), INSERM, U665, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, UMR-S665, Paris, France
- INTS, Paris, France
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Becher R, Weihmann F, Deising HB, Wirsel SG. Development of a novel multiplex DNA microarray for Fusarium graminearum and analysis of azole fungicide responses. BMC Genomics 2011; 12:52. [PMID: 21255412 PMCID: PMC3037902 DOI: 10.1186/1471-2164-12-52] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Accepted: 01/21/2011] [Indexed: 11/29/2022] Open
Abstract
Background The toxigenic fungal plant pathogen Fusarium graminearum compromises wheat production worldwide. Azole fungicides play a prominent role in controlling this pathogen. Sequencing of its genome stimulated the development of high-throughput technologies to study mechanisms of coping with fungicide stress and adaptation to fungicides at a previously unprecedented precision. DNA-microarrays have been used to analyze genome-wide gene expression patterns and uncovered complex transcriptional responses. A recently developed one-color multiplex array format allowed flexible, effective, and parallel examinations of eight RNA samples. Results We took advantage of the 8 × 15 k Agilent format to design, evaluate, and apply a novel microarray covering the whole F. graminearum genome to analyze transcriptional responses to azole fungicide treatment. Comparative statistical analysis of expression profiles uncovered 1058 genes that were significantly differentially expressed after azole-treatment. Quantitative RT-PCR analysis for 31 selected genes indicated high conformity to results from the microarray hybridization. Among the 596 genes with significantly increased transcript levels, analyses using GeneOntology and FunCat annotations detected the ergosterol-biosynthesis pathway genes as the category most significantly responding, confirming the mode-of-action of azole fungicides. Cyp51A, which is one of the three F. graminearum paralogs of Cyp51 encoding the target of azoles, was the most consistently differentially expressed gene of the entire study. A molecular phylogeny analyzing the relationships of the three CYP51 proteins in the context of 38 fungal genomes belonging to the Pezizomycotina indicated that CYP51C (FGSG_11024) groups with a new clade of CYP51 proteins. The transcriptional profiles for genes encoding ABC transporters and transcription factors suggested several involved in mechanisms alleviating the impact of the fungicide. Comparative analyses with published microarray experiments obtained from two different nutritional stress conditions identified subsets of genes responding to different types of stress. Some of the genes that responded only to tebuconazole treatment appeared to be unique to the F. graminearum genome. Conclusions The novel F. graminearum 8 × 15 k microarray is a reliable and efficient high-throughput tool for genome-wide expression profiling experiments in fungicide research, and beyond, as shown by our data obtained for azole responses. The array data contribute to understanding mechanisms of fungicide resistance and allow identifying fungicide targets.
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Affiliation(s)
- Rayko Becher
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120 Halle (Saale), Germany
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Zarrineh P, Fierro AC, Sánchez-Rodríguez A, De Moor B, Engelen K, Marchal K. COMODO: an adaptive coclustering strategy to identify conserved coexpression modules between organisms. Nucleic Acids Res 2010; 39:e41. [PMID: 21149270 PMCID: PMC3074154 DOI: 10.1093/nar/gkq1275] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Increasingly large-scale expression compendia for different species are becoming available. By exploiting the modularity of the coexpression network, these compendia can be used to identify biological processes for which the expression behavior is conserved over different species. However, comparing module networks across species is not trivial. The definition of a biologically meaningful module is not a fixed one and changing the distance threshold that defines the degree of coexpression gives rise to different modules. As a result when comparing modules across species, many different partially overlapping conserved module pairs across species exist and deciding which pair is most relevant is hard. Therefore, we developed a method referred to as conserved modules across organisms (COMODO) that uses an objective selection criterium to identify conserved expression modules between two species. The method uses as input microarray data and a gene homology map and provides as output pairs of conserved modules and searches for the pair of modules for which the number of sharing homologs is statistically most significant relative to the size of the linked modules. To demonstrate its principle, we applied COMODO to study coexpression conservation between the two well-studied bacteria Escherichia coli and Bacillus subtilis. COMODO is available at: http://homes.esat.kuleuven.be/∼kmarchal/Supplementary_Information_Zarrineh_2010/comodo/index.html.
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Affiliation(s)
- Peyman Zarrineh
- Department of Electrical Engineering, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, 3001 Leuven, Belgium
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Cohen D, Bogeat-Triboulot MB, Tisserant E, Balzergue S, Martin-Magniette ML, Lelandais G, Ningre N, Renou JP, Tamby JP, Le Thiec D, Hummel I. Comparative transcriptomics of drought responses in Populus: a meta-analysis of genome-wide expression profiling in mature leaves and root apices across two genotypes. BMC Genomics 2010; 11:630. [PMID: 21073700 PMCID: PMC3091765 DOI: 10.1186/1471-2164-11-630] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Accepted: 11/12/2010] [Indexed: 12/18/2022] Open
Abstract
Background Comparative genomics has emerged as a promising means of unravelling the molecular networks underlying complex traits such as drought tolerance. Here we assess the genotype-dependent component of the drought-induced transcriptome response in two poplar genotypes differing in drought tolerance. Drought-induced responses were analysed in leaves and root apices and were compared with available transcriptome data from other Populus species. Results Using a multi-species designed microarray, a genomic DNA-based selection of probesets provided an unambiguous between-genotype comparison. Analyses of functional group enrichment enabled the extraction of processes physiologically relevant to drought response. The drought-driven changes in gene expression occurring in root apices were consistent across treatments and genotypes. For mature leaves, the transcriptome response varied weakly but in accordance with the duration of water deficit. A differential clustering algorithm revealed similar and divergent gene co-expression patterns among the two genotypes. Since moderate stress levels induced similar physiological responses in both genotypes, the genotype-dependent transcriptional responses could be considered as intrinsic divergences in genome functioning. Our meta-analysis detected several candidate genes and processes that are differentially regulated in root and leaf, potentially under developmental control, and preferentially involved in early and long-term responses to drought. Conclusions In poplar, the well-known drought-induced activation of sensing and signalling cascades was specific to the early response in leaves but was found to be general in root apices. Comparing our results to what is known in arabidopsis, we found that transcriptional remodelling included signalling and a response to energy deficit in roots in parallel with transcriptional indices of hampered assimilation in leaves, particularly in the drought-sensitive poplar genotype.
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Affiliation(s)
- David Cohen
- INRA, Nancy Université, UMR1137 Ecologie et Ecophysiologie Forestières, IFR 110 EFABA, F-54280 Champenoux, France
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35
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Lelandais G, Devaux F. Comparative Functional Genomics of Stress Responses in Yeasts. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2010; 14:501-15. [DOI: 10.1089/omi.2010.0029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Gaëlle Lelandais
- Dynamique des Structures et Interactions des Macromolécules Biologiques (DSIMB), INSERM UMR-S 665, Université Paris Diderot, Paris France
| | - Frédéric Devaux
- Laboratoire de génomique des microorganismes, CNRS FRE3214, Université Pierre et Marie Curie, Institut des Cordeliers, Paris, France
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Le HS, Oltvai ZN, Bar-Joseph Z. Cross-species queries of large gene expression databases. ACTA ACUST UNITED AC 2010; 26:2416-23. [PMID: 20702396 DOI: 10.1093/bioinformatics/btq451] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
MOTIVATION Expression databases, including the Gene Expression Omnibus and ArrayExpress, have experienced significant growth over the past decade and now hold hundreds of thousands of arrays from multiple species. Since most drugs are initially tested on model organisms, the ability to compare expression experiments across species may help identify pathways that are activated in a similar way in humans and other organisms. However, while several methods exist for finding co-expressed genes in the same species as a query gene, looking at co-expression of homologs or arbitrary genes in other species is challenging. Unlike sequence, which is static, expression is dynamic and changes between tissues, conditions and time. Thus, to carry out cross-species analysis using these databases, we need methods that can match experiments in one species with experiments in another species. RESULTS To facilitate queries in large databases, we developed a new method for comparing expression experiments from different species. We define a distance metric between the ranking of orthologous genes in the two species. We show how to solve an optimization problem for learning the parameters of this function using a training dataset of known similar expression experiments pairs. The function we learn outperforms previous methods and simpler rank comparison methods that have been used in the past for single species analysis. We used our method to compare millions of array pairs from mouse and human expression experiments. The resulting matches can be used to find functionally related genes, to hypothesize about biological response mechanisms and to highlight conditions and diseases that are activating similar pathways in both species. AVAILABILITY Supporting methods, results and a Matlab implementation are available from http://sb.cs.cmu.edu/ExpQ/.
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Affiliation(s)
- Hai-Son Le
- Machine Learning Department, Carnegie Mellon University, Pittsburgh, PA, USA
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Kuo D, Tan K, Zinman G, Ravasi T, Bar-Joseph Z, Ideker T. Evolutionary divergence in the fungal response to fluconazole revealed by soft clustering. Genome Biol 2010; 11:R77. [PMID: 20653936 PMCID: PMC2926788 DOI: 10.1186/gb-2010-11-7-r77] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 07/09/2010] [Accepted: 07/23/2010] [Indexed: 11/25/2022] Open
Abstract
Background Fungal infections are an emerging health risk, especially those involving yeast that are resistant to antifungal agents. To understand the range of mechanisms by which yeasts can respond to anti-fungals, we compared gene expression patterns across three evolutionarily distant species - Saccharomyces cerevisiae, Candida glabrata and Kluyveromyces lactis - over time following fluconazole exposure. Results Conserved and diverged expression patterns were identified using a novel soft clustering algorithm that concurrently clusters data from all species while incorporating sequence orthology. The analysis suggests complementary strategies for coping with ergosterol depletion by azoles - Saccharomyces imports exogenous ergosterol, Candida exports fluconazole, while Kluyveromyces does neither, leading to extreme sensitivity. In support of this hypothesis we find that only Saccharomyces becomes more azole resistant in ergosterol-supplemented media; that this depends on sterol importers Aus1 and Pdr11; and that transgenic expression of sterol importers in Kluyveromyces alleviates its drug sensitivity. Conclusions We have compared the dynamic transcriptional responses of three diverse yeast species to fluconazole treatment using a novel clustering algorithm. This approach revealed significant divergence among regulatory programs associated with fluconazole sensitivity. In future, such approaches might be used to survey a wider range of species, drug concentrations and stimuli to reveal conserved and divergent molecular response pathways.
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Affiliation(s)
- Dwight Kuo
- Department of Bioengineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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Xue-Franzén Y, Johnsson A, Brodin D, Henriksson J, Bürglin TR, Wright APH. Genome-wide characterisation of the Gcn5 histone acetyltransferase in budding yeast during stress adaptation reveals evolutionarily conserved and diverged roles. BMC Genomics 2010; 11:200. [PMID: 20338033 PMCID: PMC2861062 DOI: 10.1186/1471-2164-11-200] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Accepted: 03/25/2010] [Indexed: 12/30/2022] Open
Abstract
Background Gcn5 is a transcriptional coactivator with histone acetyltransferase activity that is conserved with regard to structure as well as its histone substrates throughout the eukaryotes. Gene regulatory networks within cells are thought to be evolutionarily diverged. The use of evolutionarily divergent yeast species, such as S. cerevisiae and S. pombe, which can be studied under similar environmental conditions, provides an opportunity to examine the interface between conserved regulatory components and their cellular applications in different organisms. Results We show that Gcn5 is important for a common set of stress responses in evolutionarily diverged yeast species and that the activity of the conserved histone acetyltransferase domain is required. We define a group of KCl stress response genes in S. cerevisiae that are specifically dependent on Gcn5. Gcn5 is localised to many Gcn5-dependent genes including Gcn5 repressed targets such as FLO8. Gcn5 regulates divergent sets of KCl responsive genes in S. cerevisiae and S. pombe. Genome-wide localization studies showed a tendency for redistribution of Gcn5 during KCl stress adaptation in S. cerevisiae from short genes to the transcribed regions of long genes. An analogous redistribution was not observed in S. pombe. Conclusions Gcn5 is required for the regulation of divergent sets of KCl stress-response genes in S. cerevisiae and S. pombe even though it is required a common group of stress responses, including the response to KCl. Genes that are physically associated with Gcn5 require its activity for their repression or activation during stress adaptation, providing support for a role of Gcn5 as a corepressor as well as a coactivator. The tendency of Gcn5 to re-localise to the transcribed regions of long genes during KCl stress adaptation suggests that Gcn5 plays a specific role in the expression of long genes under adaptive conditions, perhaps by regulating transcriptional elongation as has been seen for Gcn5 in S. pombe. Interestingly an analogous redistribution of Gcn5 is not seen in S. pombe. The study thus provides important new insights in relation to why coregulators like Gcn5 are required for the correct expression of some genes but not others.
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Hori TS, Gamperl AK, Afonso LOB, Johnson SC, Hubert S, Kimball J, Bowman S, Rise ML. Heat-shock responsive genes identified and validated in Atlantic cod (Gadus morhua) liver, head kidney and skeletal muscle using genomic techniques. BMC Genomics 2010; 11:72. [PMID: 20109224 PMCID: PMC2830189 DOI: 10.1186/1471-2164-11-72] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2009] [Accepted: 01/28/2010] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Daily and seasonal changes in temperature are challenges that fish within aquaculture settings cannot completely avoid, and are known to elicit complex organismal and cellular stress responses. We conducted a large-scale gene discovery and transcript expression study in order to better understand the genes that are potentially involved in the physiological and cellular aspects of stress caused by heat-shock. We used suppression subtractive hybridization (SSH) cDNA library construction and characterization to identify transcripts that were dysregulated by heat-shock in liver, skeletal muscle and head kidney of Atlantic cod. These tissues were selected due to their roles in metabolic regulation, locomotion and growth, and immune function, respectively. Fish were exposed for 3 hours to an 8 degrees C elevation in temperature, and then allowed to recover for 24 hours at the original temperature (i.e. 10 degrees C). Tissue samples obtained before heat-shock (BHS), at the cessation of heat-shock (CS), and 3, 12, and 24 hours after the cessation of heat-shock (ACS), were used for reciprocal SSH library construction and quantitative reverse transcription - polymerase chain reaction (QPCR) analysis of gene expression using samples from a group that was transferred but not heat-shocked (CT) as controls. RESULTS We sequenced and characterized 4394 ESTs (1524 from liver, 1451 from head kidney and 1419 from skeletal muscle) from three "forward subtracted" libraries (enriched for genes up-regulated by heat-shock) and 1586 from the liver "reverse subtracted" library (enriched for genes down-regulated by heat-shock), for a total of 5980 ESTs. Several cDNAs encoding putative chaperones belonging to the heat-shock protein (HSP) family were found in these libraries, and "protein folding" was among the gene ontology (GO) terms with the highest proportion in the libraries. QPCR analysis of HSP90alpha and HSP70-1 (synonym: HSPA1A) mRNA expression showed significant up-regulation in all three tissues studied. These transcripts were more than 100-fold up-regulated in liver following heat-shock. We also identified HSP47, GRP78 and GRP94-like transcripts, which were significantly up-regulated in all 3 tissues studied. Toll-like receptor 22 (TLR22) transcript, found in the liver reverse SSH library, was shown by QPCR to be significantly down-regulated in the head kidney after heat-shock. CONCLUSION Chaperones are an important part of the cellular response to stress, and genes identified in this work may play important roles in resistance to thermal-stress. Moreover, the transcript for one key immune response gene (TLR22) was down-regulated by heat-shock, and this down-regulation may be a component of heat-induced immunosuppression.
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Affiliation(s)
- Tiago S Hori
- Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada
| | - A Kurt Gamperl
- Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada
| | - Luis OB Afonso
- British Columbia Centre for Aquatic Health Sciences, Campbell River, BC, V9W 2C2, Canada
| | - Stewart C Johnson
- Pacific Biological Station, Department for Fisheries and Oceans, Nanaimo, BC, V9T 6N7, Canada
| | - Sophie Hubert
- The Atlantic Genome Centre, Halifax, NS, B3H 3Z1, Canada
| | - Jennifer Kimball
- Institute for Marine Biosciences, National Research Council of Canada, Halifax, NS, B3H 3Z1, Canada
| | - Sharen Bowman
- The Atlantic Genome Centre, Halifax, NS, B3H 3Z1, Canada
| | - Matthew L Rise
- Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada
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Thompson DA, Regev A. Fungal regulatory evolution: cis and trans in the balance. FEBS Lett 2010; 583:3959-65. [PMID: 19914250 PMCID: PMC2823291 DOI: 10.1016/j.febslet.2009.11.032] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Revised: 11/09/2009] [Accepted: 11/10/2009] [Indexed: 11/25/2022]
Abstract
Regulatory divergence is likely a major driving force in evolution. Comparative genomics is being increasingly used to infer the evolution of gene regulation. Ascomycota fungi are uniquely suited among eukaryotes for regulatory evolution studies, due to broad phylogenetic scope, many sequenced genomes, and tractability of genomic analysis. Here we review recent advances in the identification of the contribution of cis- and trans-factors to expression divergence. Whereas current strategies have led to the discovery of surprising signatures and mechanisms, we still understand very little about the adaptive role of regulatory evolution. Empirical studies including experimental evolution, comparative functional genomics and hybrid and engineered strains are showing early promise toward deciphering the contribution of regulatory divergence to adaptation.
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Affiliation(s)
- Dawn Anne Thompson
- Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge, MA 01242, USA
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Wohlbach DJ, Thompson DA, Gasch AP, Regev A. From elements to modules: regulatory evolution in Ascomycota fungi. Curr Opin Genet Dev 2009; 19:571-8. [PMID: 19879128 DOI: 10.1016/j.gde.2009.09.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Revised: 09/03/2009] [Accepted: 09/11/2009] [Indexed: 12/13/2022]
Abstract
Regulatory divergence is likely a major driving force in evolution. Comparative transcriptomics provides a new glimpse into the evolution of gene regulation. Ascomycota fungi are uniquely suited among eukaryotes for studies of regulatory evolution, because of broad phylogenetic scope, many sequenced genomes, and facility of genomic analysis. Here we review the substantial divergence in gene expression in Ascomycota and how this is reconciled with the modular organization of transcriptional networks. We show that flexibility and redundancy in both cis-regulation and trans-regulation can lead to changes from altered expression of single genes to wholesale rewiring of regulatory modules. Redundancy thus emerges as a major driving force facilitating expression divergence while preserving the coherent functional organization of a transcriptional response.
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Affiliation(s)
- Dana J Wohlbach
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
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Lu Y, Huggins P, Bar-Joseph Z. Cross species analysis of microarray expression data. Bioinformatics 2009; 25:1476-83. [PMID: 19357096 DOI: 10.1093/bioinformatics/btp247] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
MOTIVATION Many biological systems operate in a similar manner across a large number of species or conditions. Cross-species analysis of sequence and interaction data is often applied to determine the function of new genes. In contrast to these static measurements, microarrays measure the dynamic, condition-specific response of complex biological systems. The recent exponential growth in microarray expression datasets allows researchers to combine expression experiments from multiple species to identify genes that are not only conserved in sequence but also operated in a similar way in the different species studied. RESULTS In this review we discuss the computational and technical challenges associated with these studies, the approaches that have been developed to address these challenges and the advantages of cross-species analysis of microarray data. We show how successful application of these methods lead to insights that cannot be obtained when analyzing data from a single species. We also highlight current open problems and discuss possible ways to address them.
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Affiliation(s)
- Yong Lu
- School of Computer Science and Lane Center for Computational Biology, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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