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Muñoz-Guzmán F, Caballero V, Larrondo LF. A global search for novel transcription factors impacting the Neurospora crassa circadian clock. G3 (BETHESDA, MD.) 2021; 11:jkab100. [PMID: 33792687 PMCID: PMC8495738 DOI: 10.1093/g3journal/jkab100] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 03/16/2021] [Indexed: 01/15/2023]
Abstract
Eukaryotic circadian oscillators share a common circuit architecture, a negative feedback loop in which a positive element activates the transcription of a negative one that then represses the action of the former, inhibiting its own expression. While studies in mammals and insects have revealed additional transcriptional inputs modulating the expression of core clock components, this has been less characterized in the model Neurospora crassa, where the participation of other transcriptional components impacting circadian clock dynamics remains rather unexplored. Thus, we sought to identify additional transcriptional regulators modulating the N. crassa clock, following a reverse genetic screen based on luminescent circadian reporters and a collection of transcription factors (TFs) knockouts, successfully covering close to 60% of them. Besides the canonical core clock components WC-1 and -2, none of the tested transcriptional regulators proved to be essential for rhythmicity. Nevertheless, we identified a set of 23 TFs that when absent lead to discrete, but significant, changes in circadian period. While the current level of analysis does not provide mechanistic information about how these new players modulate circadian parameters, the results of this screen reveal that an important number of light and clock-regulated TFs, involved in a plethora of processes, are capable of modulating the clockworks. This partial reverse genetic clock screen also exemplifies how the N. crassa knockout collection continues to serve as an expedite platform to address broad biological questions.
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Affiliation(s)
- Felipe Muñoz-Guzmán
- ANID—Millennium Science Initiative Program—Millennium Institute for Integrative Biology (iBio), Santiago 8331150, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Valeria Caballero
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Luis F Larrondo
- ANID—Millennium Science Initiative Program—Millennium Institute for Integrative Biology (iBio), Santiago 8331150, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
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2
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Beier S, Hinterdobler W, Monroy AA, Bazafkan H, Schmoll M. The Kinase USK1 Regulates Cellulase Gene Expression and Secondary Metabolite Biosynthesis in Trichoderma reesei. Front Microbiol 2020; 11:974. [PMID: 32508786 PMCID: PMC7251307 DOI: 10.3389/fmicb.2020.00974] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 04/22/2020] [Indexed: 01/04/2023] Open
Abstract
The complex environment of fungi requires a delicate balance between the efforts to acquire nutrition, to reproduce, and to fend off competitors. In Trichoderma reesei, an interrelationship between regulation of enzyme gene expression and secondary metabolism was shown. In this study, we investigated the physiological relevance of the unique YPK1-type kinase USK1 of T. reesei. Usk1 is located in the vicinity of the SOR cluster and is involved in regulation of several genes from this secondary metabolite cluster as well as dihydrotrichotetronine and other secondary metabolites. Moreover, USK1 is required for biosynthesis of normal levels of secondary metabolites in liquid culture. USK1 positively influences cellulase gene regulation, secreted cellulase activity, and biomass formation upon growth in constant darkness on cellulose. Positive effects of USK1 on transcript abundance of the regulator of secondary metabolism, vel1, and the carbon catabolite repressor gene cre1 are in agreement with these functions. In summary, we found that with USK1, T. reesei comprises a unique kinase that adds an additional layer of regulation to the connection of secondary metabolism and enzyme production in fungi.
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Affiliation(s)
- Sabrina Beier
- Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Tulln, Austria
| | - Wolfgang Hinterdobler
- Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Tulln, Austria
| | - Alberto Alonso Monroy
- Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Tulln, Austria
| | - Hoda Bazafkan
- Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Tulln, Austria
| | - Monika Schmoll
- Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Tulln, Austria
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3
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Bissaro B, Várnai A, Røhr ÅK, Eijsink VGH. Oxidoreductases and Reactive Oxygen Species in Conversion of Lignocellulosic Biomass. Microbiol Mol Biol Rev 2018; 82:e00029-18. [PMID: 30257993 PMCID: PMC6298611 DOI: 10.1128/mmbr.00029-18] [Citation(s) in RCA: 152] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Biomass constitutes an appealing alternative to fossil resources for the production of materials and energy. The abundance and attractiveness of vegetal biomass come along with challenges pertaining to the intricacy of its structure, evolved during billions of years to face and resist abiotic and biotic attacks. To achieve the daunting goal of plant cell wall decomposition, microorganisms have developed many (enzymatic) strategies, from which we seek inspiration to develop biotechnological processes. A major breakthrough in the field has been the discovery of enzymes today known as lytic polysaccharide monooxygenases (LPMOs), which, by catalyzing the oxidative cleavage of recalcitrant polysaccharides, allow canonical hydrolytic enzymes to depolymerize the biomass more efficiently. Very recently, it has been shown that LPMOs are not classical monooxygenases in that they can also use hydrogen peroxide (H2O2) as an oxidant. This discovery calls for a revision of our understanding of how lignocellulolytic enzymes are connected since H2O2 is produced and used by several of them. The first part of this review is dedicated to the LPMO paradigm, describing knowns, unknowns, and uncertainties. We then present different lignocellulolytic redox systems, enzymatic or not, that depend on fluxes of reactive oxygen species (ROS). Based on an assessment of these putatively interconnected systems, we suggest that fine-tuning of H2O2 levels and proximity between sites of H2O2 production and consumption are important for fungal biomass conversion. In the last part of this review, we discuss how our evolving understanding of redox processes involved in biomass depolymerization may translate into industrial applications.
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Affiliation(s)
- Bastien Bissaro
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway
| | - Anikó Várnai
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway
| | - Åsmund K Røhr
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway
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4
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Wang Z, Wang J, Li N, Li J, Trail F, Dunlap JC, Townsend JP. Light sensing by opsins and fungal ecology: NOP-1 modulates entry into sexual reproduction in response to environmental cues. Mol Ecol 2017; 27:216-232. [PMID: 29134709 DOI: 10.1111/mec.14425] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 09/30/2017] [Accepted: 10/16/2017] [Indexed: 01/25/2023]
Abstract
Understanding the genetic basis of the switch from asexual to sexual lifestyles in response to sometimes rapid environmental changes is one of the major challenges in fungal ecology. Light appears to play a critical role in the asexual-sexual switch-but fungal genomes harbour diverse light sensors. Fungal opsins are homologous to bacterial green-light-sensory rhodopsins, and their organismal functions in fungi have not been well understood. Three of these opsin-like proteins were widely distributed across fungal genomes, but homologs of the Fusarium opsin-like protein CarO were present only in plant-associated fungi. Key amino acids, including potential retinal binding sites, functionally diverged on the phylogeny of opsins. This diversification of opsin-like proteins could be correlated with life history-associated differences among fungi in their expression and function during morphological development. In Neurospora crassa and related species, knockout of the opsin NOP-1 led to a phenotype in the regulation of the asexual-sexual switch, modulating response to both light and oxygen conditions. Sexual development commenced early in ∆nop-1 strains cultured in unsealed plates under constant blue and white light. Furthermore, comparative transcriptomics showed that the expression of nop-1 is light-dependent and that the ∆nop-1 strain abundantly expresses genes involved in oxidative stress response, genes enriched in NAD/NADP binding sites, genes with functions in proton transmembrane movement and catalase activity, and genes involved in the homeostasis of protons. Based on these observations, we contend that light and oxidative stress regulate the switch via light-responsive and ROS pathways in model fungus N. crassa and other fungi.
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Affiliation(s)
- Zheng Wang
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA.,Department of Biostatistics, Yale School of Public Health, New Haven, CT, USA
| | - Junrui Wang
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, USA.,Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Ning Li
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
| | - Jigang Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Frances Trail
- Department of Plant Biology, Department of Plant Pathology, Michigan State University, East Lansing, MI, USA
| | - Jay C Dunlap
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Jeffrey P Townsend
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA.,Department of Biostatistics, Yale School of Public Health, New Haven, CT, USA.,Program in Microbiology, Yale University, New Haven, CT, USA
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5
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Gonçalves AP, Heller J, Daskalov A, Videira A, Glass NL. Regulated Forms of Cell Death in Fungi. Front Microbiol 2017; 8:1837. [PMID: 28983298 PMCID: PMC5613156 DOI: 10.3389/fmicb.2017.01837] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 09/07/2017] [Indexed: 12/15/2022] Open
Abstract
Cell death occurs in all domains of life. While some cells die in an uncontrolled way due to exposure to external cues, other cells die in a regulated manner as part of a genetically encoded developmental program. Like other eukaryotic species, fungi undergo programmed cell death (PCD) in response to various triggers. For example, exposure to external stress conditions can activate PCD pathways in fungi. Calcium redistribution between the extracellular space, the cytoplasm and intracellular storage organelles appears to be pivotal for this kind of cell death. PCD is also part of the fungal life cycle, in which it occurs during sexual and asexual reproduction, aging, and as part of development associated with infection in phytopathogenic fungi. Additionally, a fungal non-self-recognition mechanism termed heterokaryon incompatibility (HI) also involves PCD. Some of the molecular players mediating PCD during HI show remarkable similarities to major constituents involved in innate immunity in metazoans and plants. In this review we discuss recent research on fungal PCD mechanisms in comparison to more characterized mechanisms in metazoans. We highlight the role of PCD in fungi in response to exogenic compounds, fungal development and non-self-recognition processes and discuss identified intracellular signaling pathways and molecules that regulate fungal PCD.
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Affiliation(s)
- A Pedro Gonçalves
- Plant and Microbial Biology Department, University of California, BerkeleyBerkeley, CA, United States
| | - Jens Heller
- Plant and Microbial Biology Department, University of California, BerkeleyBerkeley, CA, United States
| | - Asen Daskalov
- Plant and Microbial Biology Department, University of California, BerkeleyBerkeley, CA, United States
| | - Arnaldo Videira
- Instituto de Ciências Biomédicas de Abel Salazar, Universidade do PortoPorto, Portugal.,I3S - Instituto de Investigação e Inovação em SaúdePorto, Portugal
| | - N Louise Glass
- Plant and Microbial Biology Department, University of California, BerkeleyBerkeley, CA, United States
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Assessing the relevance of light for fungi: Implications and insights into the network of signal transmission. ADVANCES IN APPLIED MICROBIOLOGY 2016; 76:27-78. [PMID: 21924971 DOI: 10.1016/b978-0-12-387048-3.00002-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Light represents an important environmental cue, which provides information enabling fungi to prepare and react to the different ambient conditions between day and night. This adaptation requires both anticipation of the changing conditions, which is accomplished by daily rhythmicity of gene expression brought about by the circadian clock, and reaction to sudden illumination. Besides perception of the light signal, also integration of this signal with other environmental cues, most importantly nutrient availability, necessitates light-dependent regulation of signal transduction pathways and metabolic pathways. An influence of light and/or the circadian clock is known for the cAMP pathway, heterotrimeric G-protein signaling, mitogen-activated protein kinases, two-component phosphorelays, and Ca(2+) signaling. Moreover, also the target of rapamycin signaling pathway and reactive oxygen species as signal transducing elements are assumed to be connected to the light-response pathway. The interplay of the light-response pathway with signaling cascades results in light-dependent regulation of primary and secondary metabolism, morphology, development, biocontrol activity, and virulence. The frequent use of fungi in biotechnology as well as analysis of fungi in the artificial environment of a laboratory therefore requires careful consideration of still operative evolutionary heritage of these organisms. This review summarizes the diverse effects of light on fungi and the mechanisms they apply to deal both with the information content and with the harmful properties of light. Additionally, the implications of the reaction of fungi to light in a laboratory environment for experimental work and industrial applications are discussed.
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Pedro Gonçalves A, Silva N, Oliveira C, Kowbel DJ, Glass NL, Kijjoa A, Palmeira A, Sousa E, Pinto M, Videira A. Transcription profiling of the Neurospora crassa response to a group of synthetic (thio)xanthones and a natural acetophenone. GENOMICS DATA 2015; 4:26-32. [PMID: 26484172 PMCID: PMC4535624 DOI: 10.1016/j.gdata.2015.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 02/12/2015] [Accepted: 02/13/2015] [Indexed: 12/25/2022]
Abstract
Xanthones are a class of heterocyclic compounds characterized by a dibenzo-γ-pyrone nucleus. Analysis of their mode of action in cells, namely uncovering alterations in gene expression, is important because these compounds have potential therapeutic applications. Thus, we studied the transcriptional response of the filamentous fungus Neurospora crassa to a group of synthetic (thio)xanthone derivatives with antitumor activity using high throughput RNA sequencing. The induction of ABC transporters in N. crassa, particularly atrb and cdr4, is a common consequence of the treatment with xanthones. In addition, we found a group of genes repressed by all of the tested (thio)xanthone derivatives, that are evocative of genes downregulated during oxidative stress. The transcriptional response of N. crassa treated with an acetophenone isolated from the soil fungus Neosartorya siamensis shares some features with the (thio)xanthone-elicited gene expression profiles. Two of the (thio)xanthone derivatives and the N. siamensis-derived acetophenone inhibited the growth of N. crassa. Our work also provides framework datasets that may orientate future studies on the mechanisms of action of some groups of xanthones.
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Affiliation(s)
- A Pedro Gonçalves
- ICBAS-Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal ; IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Nuno Silva
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Carla Oliveira
- ICBAS-Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - David J Kowbel
- Plant and Microbial Biology Department, The University of California, Berkeley, CA 94720, USA
| | - N Louise Glass
- Plant and Microbial Biology Department, The University of California, Berkeley, CA 94720, USA
| | - Anake Kijjoa
- ICBAS-Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal ; Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR), Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal
| | - Andreia Palmeira
- Centro de Química Medicinal da Universidade do Porto (CEQUIMED-UP), University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal ; Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - Emília Sousa
- Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR), Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal ; Centro de Química Medicinal da Universidade do Porto (CEQUIMED-UP), University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal ; Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - Madalena Pinto
- Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR), Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal ; Centro de Química Medicinal da Universidade do Porto (CEQUIMED-UP), University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal ; Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - Arnaldo Videira
- ICBAS-Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal ; IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal ; Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal
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Gonçalves AP, Monteiro J, Lucchi C, Kowbel DJ, Cordeiro JM, Correia-de-Sá P, Rigden DJ, Glass NL, Videira A. Extracellular calcium triggers unique transcriptional programs and modulates staurosporine-induced cell death in Neurospora crassa. MICROBIAL CELL 2014; 1:289-302. [PMID: 28357255 PMCID: PMC5349132 DOI: 10.15698/mic2014.09.165] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Alterations in the intracellular levels of calcium are a common response to cell death stimuli in animals and fungi and, particularly, in the Neurospora crassa response to staurosporine. We highlight the importance of the extracellular availability of Ca2+ for this response. Limitation of the ion in the culture medium further sensitizes cells to the drug and results in increased accumulation of reactive oxygen species (ROS). Conversely, an approximately 30-fold excess of external Ca2+ leads to increased drug tolerance and lower ROS generation. In line with this, distinct staurosporine-induced cytosolic Ca2+ signaling profiles were observed in the absence or presence of excessive external Ca2+. High-throughput RNA sequencing revealed that different concentrations of extracellular Ca2+ define distinct transcriptional programs. Our transcriptional profiling also pointed to two putative novel Ca2+-binding proteins, encoded by the NCU08524 and NCU06607 genes, and provides a reference dataset for future investigations on the role of Ca2+ in fungal biology.
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Affiliation(s)
- A P Gonçalves
- ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal. ; IBMC-Instituto de Biologia Molecular e Celular - Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - João Monteiro
- IBMC-Instituto de Biologia Molecular e Celular - Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Chiara Lucchi
- IBMC-Instituto de Biologia Molecular e Celular - Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - David J Kowbel
- Plant and Microbial Biology Department, The University of California, Berkeley, CA 94720, USA
| | - J M Cordeiro
- ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal. ; UMIB-Unidade Multidisciplinar de Investigação Biomédica, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Paulo Correia-de-Sá
- ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal. ; UMIB-Unidade Multidisciplinar de Investigação Biomédica, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Daniel J Rigden
- Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, United Kingdom
| | - N L Glass
- Plant and Microbial Biology Department, The University of California, Berkeley, CA 94720, USA
| | - Arnaldo Videira
- ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal. ; IBMC-Instituto de Biologia Molecular e Celular - Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
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Kollath-Leiß K, Bönniger C, Sardar P, Kempken F. BEM46 shows eisosomal localization and association with tryptophan-derived auxin pathway in Neurospora crassa. EUKARYOTIC CELL 2014; 13:1051-63. [PMID: 24928924 PMCID: PMC4135797 DOI: 10.1128/ec.00061-14] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 06/06/2014] [Indexed: 11/20/2022]
Abstract
BEM46 proteins are evolutionarily conserved, but their functions remain elusive. We reported previously that the BEM46 protein in Neurospora crassa is targeted to the endoplasmic reticulum (ER) and is essential for ascospore germination. In the present study, we established a bem46 knockout strain of N. crassa. This Δbem46 mutant exhibited a level of ascospore germination lower than that of the wild type but much higher than those of the previously characterized bem46-overexpressing and RNA interference (RNAi) lines. Reinvestigation of the RNAi transformants revealed two types of alternatively spliced bem46 mRNA; expression of either type led to a loss of ascospore germination. Our results indicated that the phenotype was not due to bem46 mRNA downregulation or loss but was caused by the alternatively spliced mRNAs and the peptides they encoded. Using the N. crassa ortholog of the eisosomal protein PILA from Aspergillus nidulans, we further demonstrated the colocalization of BEM46 with eisosomes. Employing the yeast two-hybrid system, we identified a single interaction partner: anthranilate synthase component II (encoded by trp-1). This interaction was confirmed in vivo by a split-YFP (yellow fluorescent protein) approach. The Δtrp-1 mutant showed reduced ascospore germination and increased indole production, and we used bioinformatic tools to identify a putative auxin biosynthetic pathway. The genes involved exhibited various levels of transcriptional regulation in the different bem46 transformant and mutant strains. We also investigated the indole production of the strains in different developmental stages. Our findings suggested that the regulation of indole biosynthesis genes was influenced by bem46 overexpression. Furthermore, we uncovered evidence of colocalization of BEM46 with the neutral amino acid transporter MTR.
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Affiliation(s)
- K Kollath-Leiß
- Abteilung Botanische Genetik und Molekularbiologie, Botanisches Institut und Botanischer Garten, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
| | - C Bönniger
- Abteilung Botanische Genetik und Molekularbiologie, Botanisches Institut und Botanischer Garten, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
| | - P Sardar
- Abteilung Botanische Genetik und Molekularbiologie, Botanisches Institut und Botanischer Garten, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
| | - F Kempken
- Abteilung Botanische Genetik und Molekularbiologie, Botanisches Institut und Botanischer Garten, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
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10
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Gonçalves AP, Cordeiro JM, Monteiro J, Muñoz A, Correia-de-Sá P, Read ND, Videira A. Activation of a TRP-like channel and intracellular Ca2+ dynamics during phospholipase-C-mediated cell death. J Cell Sci 2014; 127:3817-29. [PMID: 25037570 PMCID: PMC4150065 DOI: 10.1242/jcs.152058] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The model organism Neurospora crassa undergoes programmed cell death when exposed to staurosporine. Here, we show that staurosporine causes defined changes in cytosolic free Ca2+ ([Ca2+]c) dynamics and a distinct Ca2+ signature that involves Ca2+ influx from the external medium and internal Ca2+ stores. We investigated the molecular basis of this Ca2+ response by using [Ca2+]c measurements combined with pharmacological and genetic approaches. Phospholipase C was identified as a pivotal player during cell death, because modulation of the phospholipase C signaling pathway and deletion of PLC-2, which we show to be involved in hyphal development, results in an inability to trigger the characteristic staurosporine-induced Ca2+ signature. Using Δcch-1, Δfig-1 and Δyvc-1 mutants and a range of inhibitors, we show that extracellular Ca2+ entry does not occur through the hitherto described high- and low-affinity Ca2+ uptake systems, but through the opening of plasma membrane channels with properties resembling the transient receptor potential (TRP) family. Partial blockage of the response to staurosporine after inhibition of a putative inositol-1,4,5-trisphosphate (IP3) receptor suggests that Ca2+ release from internal stores following IP3 formation combines with the extracellular Ca2+ influx.
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Affiliation(s)
- A Pedro Gonçalves
- IBMC-Instituto de Biologia Molecular e Celular - Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - J Miguel Cordeiro
- ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - João Monteiro
- IBMC-Instituto de Biologia Molecular e Celular - Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
| | - Alberto Muñoz
- Manchester Fungal Infection Group, Institute of Inflammation and Repair, CTF Building, Grafton Street, University of Manchester, Manchester M13 9NT, UK
| | - Paulo Correia-de-Sá
- ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Nick D Read
- Manchester Fungal Infection Group, Institute of Inflammation and Repair, CTF Building, Grafton Street, University of Manchester, Manchester M13 9NT, UK
| | - Arnaldo Videira
- IBMC-Instituto de Biologia Molecular e Celular - Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
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CZT-1 is a novel transcription factor controlling cell death and natural drug resistance in Neurospora crassa. G3-GENES GENOMES GENETICS 2014; 4:1091-102. [PMID: 24717808 PMCID: PMC4065252 DOI: 10.1534/g3.114.011312] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
We pinpoint CZT-1 (cell death–activated zinc cluster transcription factor) as a novel transcription factor involved in tolerance to cell death induced by the protein kinase inhibitor staurosporine in Neurospora crassa. Transcriptional profiling of staurosporine-treated wild-type cells by RNA-sequencing showed that genes encoding the machinery for protein synthesis are enriched among the genes repressed by the drug. Functional category enrichment analyses also show that genes encoding components of the mitochondrial respiratory chain are downregulated by staurosporine, whereas genes involved in endoplasmic reticulum activities are upregulated. In contrast, a staurosporine-treated Δczt-1 deletion strain is unable to repress the genes for the respiratory chain and to induce the genes related to the endoplasmic reticulum, indicating a role for CZT-1 in the regulation of activity of these organelles. The Δczt-1 mutant strain displays increased reactive oxygen species accumulation on insult with staurosporine. A genome-wide association study of a wild population of N. crassa isolates pointed out genes associated with a cell death role of CZT-1, including catalase-1 (cat-1) and apoptosis-inducing factor–homologous mitochondrion-associated inducer of death 2 (amid-2). Importantly, differences in the expression of czt-1 correlates with resistance to staurosporine among wild isolate strains. Our results reveal a novel transcription factor that regulates drug resistance and cell death in response to staurosporine in laboratory strains as well as in wild isolates of N. crassa.
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Martins I, Hartmann DO, Alves PC, Planchon S, Renaut J, Leitão MC, Rebelo LP, Silva Pereira C. Proteomic alterations induced by ionic liquids in Aspergillus nidulans and Neurospora crassa. J Proteomics 2013; 94:262-78. [DOI: 10.1016/j.jprot.2013.09.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Revised: 09/13/2013] [Accepted: 09/27/2013] [Indexed: 02/03/2023]
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Abstract
In fungi, heterokaryon incompatibility is a nonself recognition process occurring when filaments of different isolates of the same species fuse. Compatibility is controlled by so-called het loci and fusion of strains of unlike het genotype triggers a complex incompatibility reaction that leads to the death of the fusion cell. Herein, we analyze the transcriptional changes during the incompatibility reaction in Podospora anserina. The incompatibility response was found to be associated with a massive transcriptional reprogramming: 2231 genes were up-regulated by a factor 2 or more during incompatibility. In turn, 2441 genes were down-regulated. HET, NACHT, and HeLo domains previously found to be involved in the control of heterokaryon incompatibility were enriched in the up-regulated gene set. In addition, incompatibility was characterized by an up-regulation of proteolytic and other hydrolytic activities, of secondary metabolism clusters and toxins and effector-like proteins. The up-regulated set was found to be enriched for proteins lacking orthologs in other species and chromosomal distribution of the up-regulated genes was uneven with up-regulated genes residing preferentially in genomic islands and on chromosomes IV and V. There was a significant overlap between regulated genes during incompatibility in P. anserina and Neurospora crassa, indicating similarities in the incompatibility responses in these two species. Globally, this study illustrates that the expression changes occurring during cell fusion incompatibility in P. anserina are in several aspects reminiscent of those described in host-pathogen or symbiotic interactions in other fungal species.
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Reveal BS, Paietta JV. Analysis of the sulfur-regulated control of the cystathionine γ-lyase gene of Neurospora crassa. BMC Res Notes 2012; 5:339. [PMID: 22748183 PMCID: PMC3496659 DOI: 10.1186/1756-0500-5-339] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 06/05/2012] [Indexed: 02/04/2023] Open
Abstract
Background Cystathionine γ-lyase plays a key role in the transsulfuration pathway through its primary reaction of catalyzing the formation of cysteine from cystathionine. The Neurospora crassa cystathionine γ-lyase gene (cys-16+) is of particular interest in dissecting the regulation and dynamics of transsulfuration. The aim of this study was to determine the regulatory connection of cys-16+ to the Neurospora sulfur regulatory network. In addition, the cys-16+ promoter was characterized with the goal of developing a strongly expressed and regulatable gene expression tool. Findings The cystathionine γ-lyase cys-16+ gene was cloned and characterized. The gene, which contains no introns, encodes a protein of 417 amino acids with conserved pyridoxal 5’-phosphate binding site and substrate-cofactor binding pocket. Northern blot analysis using wild type cells showed that cys-16+ transcript levels increased under sulfur limiting (derepressing) conditions and were present only at a low level under sulfur sufficient (repressing) conditions. In contrast, cys-16+ transcript levels in a Δcys-3 regulatory mutant were present at a low level under either derepressing or repressing conditions. Gel mobility shift analysis demonstrated the presence of four CYS3 transcriptional activator binding sites on the cys-16+ promoter, which were close matches to the CYS3 consensus binding sequence. Conclusions In this work, we confirm the control of cystathionine γ-lyase gene expression by the CYS3 transcriptional activator through the loss of cys-16+ expression in a Δcys-3 mutant and through the in vitro binding of CYS3 to the cys-16+ promoter at four sites. The highly regulated cys-16+ promoter should be a useful tool for gene expression studies in Neurospora
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Affiliation(s)
- Brad S Reveal
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA
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Schuster A, Bruno KS, Collett JR, Baker SE, Seiboth B, Kubicek CP, Schmoll M. A versatile toolkit for high throughput functional genomics with Trichoderma reesei. BIOTECHNOLOGY FOR BIOFUELS 2012; 5:1. [PMID: 22448811 PMCID: PMC3260098 DOI: 10.1186/1754-6834-5-1] [Citation(s) in RCA: 170] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 01/02/2012] [Indexed: 05/03/2023]
Abstract
BACKGROUND The ascomycete fungus, Trichoderma reesei (anamorph of Hypocrea jecorina), represents a biotechnological workhorse and is currently one of the most proficient cellulase producers. While strain improvement was traditionally accomplished by random mutagenesis, a detailed understanding of cellulase regulation can only be gained using recombinant technologies. RESULTS Aiming at high efficiency and high throughput methods, we present here a construction kit for gene knock out in T. reesei. We provide a primer database for gene deletion using the pyr4, amdS and hph selection markers. For high throughput generation of gene knock outs, we constructed vectors using yeast mediated recombination and then transformed a T. reesei strain deficient in non-homologous end joining (NHEJ) by spore electroporation. This NHEJ-defect was subsequently removed by crossing of mutants with a sexually competent strain derived from the parental strain, QM9414. CONCLUSIONS Using this strategy and the materials provided, high throughput gene deletion in T. reesei becomes feasible. Moreover, with the application of sexual development, the NHEJ-defect can be removed efficiently and without the need for additional selection markers. The same advantages apply for the construction of multiple mutants by crossing of strains with different gene deletions, which is now possible with considerably less hands-on time and minimal screening effort compared to a transformation approach. Consequently this toolkit can considerably boost research towards efficient exploitation of the resources of T. reesei for cellulase expression and hence second generation biofuel production.
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Affiliation(s)
- André Schuster
- Chemical and Biological Process Development, Energy and Environment Directorate, Pacific Northwest National Laboratory, 902 Battelle Blvd, Richland, WA, USA
- Research Area of Gene Technology and Applied Biochemistry, Institute for Chemical Engineering, Vienna University of Technology, Gumpendorfer Strasse 1a/1665, A-1060 Wien, Austria
| | - Kenneth S Bruno
- Chemical and Biological Process Development, Energy and Environment Directorate, Pacific Northwest National Laboratory, 902 Battelle Blvd, Richland, WA, USA
| | - James R Collett
- Chemical and Biological Process Development, Energy and Environment Directorate, Pacific Northwest National Laboratory, 902 Battelle Blvd, Richland, WA, USA
| | - Scott E Baker
- Chemical and Biological Process Development, Energy and Environment Directorate, Pacific Northwest National Laboratory, 902 Battelle Blvd, Richland, WA, USA
| | - Bernhard Seiboth
- Research Area of Gene Technology and Applied Biochemistry, Institute for Chemical Engineering, Vienna University of Technology, Gumpendorfer Strasse 1a/1665, A-1060 Wien, Austria
| | - Christian P Kubicek
- Research Area of Gene Technology and Applied Biochemistry, Institute for Chemical Engineering, Vienna University of Technology, Gumpendorfer Strasse 1a/1665, A-1060 Wien, Austria
| | - Monika Schmoll
- Research Area of Gene Technology and Applied Biochemistry, Institute for Chemical Engineering, Vienna University of Technology, Gumpendorfer Strasse 1a/1665, A-1060 Wien, Austria
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Modulation of fungal sensitivity to staurosporine by targeting proteins identified by transcriptional profiling. Fungal Genet Biol 2011; 48:1130-8. [PMID: 22001288 DOI: 10.1016/j.fgb.2011.09.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 09/28/2011] [Accepted: 09/29/2011] [Indexed: 12/19/2022]
Abstract
An analysis of the time-dependent genetic response to the death-inducer staurosporine was performed in Neurospora crassa by transcriptional profiling. Staurosporine induced two major genes encoding an ABC transporter and a protein with similarity to regulatory subunits of potassium channels. The transcriptional response is dependent on the activity of a novel transcription factor. Deletion mutants in differentially expressed genes displayed altered sensitivity to staurosporine, underscoring significant proteins involved in the response to the drug. A null-mutant of the ABC transporter (abc3) is extremely sensitive to staurosporine, accumulates more staurosporine than the wild type strain and is defective in energy-dependent export of the drug, indicating that the ABC3 protein is the first described staurosporine transporter. It was located in the plasma membrane by immunofluorescence microscopy. The combination of inhibitors of ABC transporters or of potassium channels with staurosporine leads to an enhanced activity against N. crassa and pathogenic fungi paving the way to the development of more potent and specific antifungals. Our results highlight the general use of transcriptional profiling for the identification of novel proteins involved in cell death and their potential use as drug targets.
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Dinamarco TM, Pimentel BDCF, Savoldi M, Malavazi I, Soriani FM, Uyemura SA, Ludovico P, Goldman MHS, Goldman GH. The roles played by Aspergillus nidulans apoptosis-inducing factor (AIF)-like mitochondrial oxidoreductase (AifA) and NADH-ubiquinone oxidoreductases (NdeA-B and NdiA) in farnesol resistance. Fungal Genet Biol 2010; 47:1055-69. [PMID: 20654725 DOI: 10.1016/j.fgb.2010.07.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Revised: 07/08/2010] [Accepted: 07/09/2010] [Indexed: 12/13/2022]
Abstract
Farnesol (FOH) is a nonsterol isoprenoid produced by dephosphorylation of farnesyl pyrophosphate, a catabolite of the cholesterol biosynthetic pathway. These isoprenoids inhibit proliferation and induce apoptosis. Here, we show that Aspergillus nidulans AifA encoding the apoptosis-inducing factor (AIF)-like mitochondrial oxidoreductase plays a role in the function of the mitochondrial Complex I. Additionally, we demonstrated that ndeA-B and ndiA encode external and internal alternative NADH dehydrogenases, respectively, that have a function in FOH resistance. When exposed to FOH, the ΔaifA and ΔndeA strains have increased ROS production while ΔndeB, ΔndeA ΔndeB, and ΔndiA mutant strains showed the same ROS accumulation than in the absence of FOH. We observed several compensatory mechanisms affecting the differential survival of these mutants to FOH.
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Affiliation(s)
- Taísa Magnani Dinamarco
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Avenida do Café S/N, São Paulo, Brazil
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Dieterle MG, Wiest AE, Plamann M, McCluskey K. Characterization of the temperature-sensitive mutations un-7 and png-1 in Neurospora crassa. PLoS One 2010; 5:e10703. [PMID: 20502699 PMCID: PMC2872674 DOI: 10.1371/journal.pone.0010703] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Accepted: 04/29/2010] [Indexed: 11/22/2022] Open
Abstract
The model filamentous fungus Neurospora crassa has been studied for over fifty years and many temperature-sensitive mutants have been generated. While most of these have been mapped genetically, many remain anonymous. The mutation in the N. crassa temperature-sensitive lethal mutant un-7 was identified by a complementation based approach as being in the open reading frame designated NCU00651 on linkage group I. Other mutations in this gene have been identified that lead to a temperature-sensitive morphological phenotype called png-1. The mutations underlying un-7 result in a serine to phenylalanine change at position 273 and an isoleucine to valine change at position 390, while the mutation in png-1 was found to result in a serine to leucine change at position 279 although there were other conservative changes in this allele. The overall morphology of the strain carrying the un-7 mutation is compared to strains carrying the png-1 mutation and these mutations are evaluated in the context of other temperature-sensitive mutants in Neurospora.
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Affiliation(s)
- Michael G. Dieterle
- Fungal Genetics Stock Center, School of Biological Sciences, University of Missouri- Kansas City, Kansas City, Missouri, United States of America
- Pembroke Hill School, Kansas City, Missouri, United States of America
| | - Aric E. Wiest
- Fungal Genetics Stock Center, School of Biological Sciences, University of Missouri- Kansas City, Kansas City, Missouri, United States of America
| | - Mike Plamann
- Fungal Genetics Stock Center, School of Biological Sciences, University of Missouri- Kansas City, Kansas City, Missouri, United States of America
| | - Kevin McCluskey
- Fungal Genetics Stock Center, School of Biological Sciences, University of Missouri- Kansas City, Kansas City, Missouri, United States of America
- * E-mail:
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Abstract
We studied staurosporine-induced cell death in the filamentous fungus Neurospora crassa. The generation of reactive oxygen species during the process appears to be an important signaling event, since addition of the antioxidant glutathione prevents the effects of staurosporine on fungal growth. Selected mutants with mutations in respiratory chain complex I are extremely sensitive to the drug, stressing the involvement of complex I in programmed cell death. Following this finding, we determined that the complex I-specific inhibitor rotenone used in combination with staurosporine results in a synergistic and specific antifungal activity, likely through a concerted action on intracellular glutathione depletion. Paradoxically, the synergistic antifungal activity of rotenone and staurosporine is observed in N. crassa complex I mutants and in Saccharomyces cerevisiae, which lacks complex I. In addition, it is not observed when other complex I inhibitors are used instead of rotenone. These results indicate that the rotenone effect is independent of complex I inhibition. The combination of rotenone and staurosporine is effective against N. crassa as well as against the common pathogens Aspergillus fumigatus and Candida albicans, pointing to its usefulness as an antifungal agent.
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Hutchison E, Brown S, Tian C, Glass NL. Transcriptional profiling and functional analysis of heterokaryon incompatibility in Neurospora crassa reveals that reactive oxygen species, but not metacaspases, are associated with programmed cell death. MICROBIOLOGY-SGM 2009; 155:3957-3970. [PMID: 19696111 DOI: 10.1099/mic.0.032284-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Heterokaryon incompatibility (HI) is a nonself recognition phenomenon occurring in filamentous fungi that is important for limiting resource plundering and restricting viral transfer between strains. Nonself recognition and HI occurs during hyphal fusion between strains that differ at het loci. If two strains undergo hyphal fusion, but differ in allelic specificity at a het locus, the fusion cell is compartmentalized and undergoes a rapid programmed cell death (PCD). Incompatible heterokaryons show a macroscopic phenotype of slow growth and diminished conidiation, and a microscopic phenotype of hyphal compartmentation and cell death. To understand processes associated with HI and PCD, we used whole-genome microarrays for Neurospora crassa to assess transcriptional differences associated with induction of HI mediated by differences in het-c pin-c haplotype. Our data show that HI is a dynamic and transcriptionally active process. The production of reactive oxygen species is implicated in the execution of HI and PCD in N. crassa, as are several genes involved in phosphatidylinositol and calcium signalling pathways. However, genes encoding mammalian homologues of caspases or apoptosis-inducing factor (AIF) are not required for HI or programmed cell death. These data indicate that PCD during HI occurs via a novel and possibly fungal-specific mechanism, making this pathway an attractive drug target for control of fungal infections.
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Affiliation(s)
- Elizabeth Hutchison
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720-3102, USA
| | - Sarah Brown
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720-3102, USA
| | - Chaoguang Tian
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720-3102, USA
| | - N Louise Glass
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720-3102, USA
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