1
|
Mayer A, McLaughlin G, Gladfelter A, Glass NL, Mela A, Roper M. Syncytial Assembly Lines: Consequences of Multinucleate Cellular Compartments for Fungal Protein Synthesis. Results Probl Cell Differ 2024; 71:159-183. [PMID: 37996678 DOI: 10.1007/978-3-031-37936-9_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
Fast growth and prodigious cellular outputs make fungi powerful tools in biotechnology. Recent modeling work has exposed efficiency gains associated with dividing the labor of transcription over multiple nuclei, and experimental innovations are opening new windows on the capacities and adaptations that allow nuclei to behave autonomously or in coordination while sharing a single, common cytoplasm. Although the motivation of our review is to motivate and connect recent work toward a greater understanding of fungal factories, we use the analogy of the assembly line as an organizing idea for studying coordinated gene expression, generally.
Collapse
Affiliation(s)
- Alex Mayer
- Department of Mathematics, University of California Los Angeles, Los Angeles, CA, USA
| | - Grace McLaughlin
- Department of Cell Biology, Duke University, Durham, NC, USA
- Department of Biology, University of North Carolina Chapel Hill, Chapel Hill, NC, USA
| | - Amy Gladfelter
- Department of Cell Biology, Duke University, Durham, NC, USA
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, USA
| | - Alexander Mela
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, USA
| | - Marcus Roper
- Department of Mathematics, University of California Los Angeles, Los Angeles, CA, USA.
- Department of Computational Medicine, University of California Los Angeles, Los Angeles, CA, USA.
| |
Collapse
|
2
|
Mela AP, Glass NL. Permissiveness and competition within and between Neurospora crassa syncytia. Genetics 2023; 224:iyad112. [PMID: 37313736 PMCID: PMC10411585 DOI: 10.1093/genetics/iyad112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 06/15/2023] Open
Abstract
A multinucleate syncytium is a common growth form in filamentous fungi. Comprehensive functions of the syncytial state remain unknown, but it likely allows for a wide range of adaptations to enable filamentous fungi to coordinate growth, reproduction, responses to the environment, and to distribute nuclear and cytoplasmic elements across a colony. Indeed, the underlying mechanistic details of how syncytia regulate cellular and molecular processes spatiotemporally across a colony are largely unexplored. Here, we implemented a strategy to analyze the relative fitness of different nuclear populations in syncytia of Neurospora crassa, including nuclei with loss-of-function mutations in essential genes, based on production of multinucleate asexual spores using flow cytometry of pairings between strains with differentially fluorescently tagged nuclear histones. The distribution of homokaryotic and heterokaryotic asexual spores in pairings was assessed between different auxotrophic and morphological mutants, as well as with strains that were defective in somatic cell fusion or were heterokaryon incompatible. Mutant nuclei were compartmentalized into both homokaryotic and heterokaryotic asexual spores, a type of bet hedging for maintenance and evolution of mutational events, despite disadvantages to the syncytium. However, in pairings between strains that were blocked in somatic cell fusion or were heterokaryon incompatible, we observed a "winner-takes-all" phenotype, where asexual spores originating from paired strains were predominantly one genotype. These data indicate that syncytial fungal cells are permissive and tolerate a wide array of nuclear functionality, but that cells/colonies that are unable to cooperate via syncytia formation actively compete for resources.
Collapse
Affiliation(s)
- Alexander P Mela
- The Plant and Microbial Biology Department, University of California Berkeley, Berkeley, CA 94720, USA
| | - N Louise Glass
- The Plant and Microbial Biology Department, University of California Berkeley, Berkeley, CA 94720, USA
- The Environmental Genomics and Systems Biology Division, The Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| |
Collapse
|
3
|
Villalobos-Escobedo JM, Mercado-Esquivias MB, Adams C, Kauffman WB, Malmstrom RR, Deutschbauer AM, Glass NL. Genome-wide fitness profiling reveals molecular mechanisms that bacteria use to interact with Trichoderma atroviride exometabolites. PLoS Genet 2023; 19:e1010909. [PMID: 37651474 PMCID: PMC10516422 DOI: 10.1371/journal.pgen.1010909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 09/22/2023] [Accepted: 08/07/2023] [Indexed: 09/02/2023] Open
Abstract
Trichoderma spp. are ubiquitous rhizosphere fungi capable of producing several classes of secondary metabolites that can modify the dynamics of the plant-associated microbiome. However, the bacterial-fungal mechanisms that mediate these interactions have not been fully characterized. Here, a random barcode transposon-site sequencing (RB-TnSeq) approach was employed to identify bacterial genes important for fitness in the presence of Trichoderma atroviride exudates. We selected three rhizosphere bacteria with RB-TnSeq mutant libraries that can promote plant growth: the nitrogen fixers Klebsiella michiganensis M5aI and Herbaspirillum seropedicae SmR1, and Pseudomonas simiae WCS417. As a non-rhizosphere species, Pseudomonas putida KT2440 was also included. From the RB-TnSeq data, nitrogen-fixing bacteria competed mainly for iron and required the siderophore transport system TonB/ExbB for optimal fitness in the presence of T. atroviride exudates. In contrast, P. simiae and P. putida were highly dependent on mechanisms associated with membrane lipid modification that are required for resistance to cationic antimicrobial peptides (CAMPs). A mutant in the Hog1-MAP kinase (Δtmk3) gene of T. atroviride showed altered expression patterns of many nonribosomal peptide synthetase (NRPS) biosynthetic gene clusters with potential antibiotic activity. In contrast to exudates from wild-type T. atroviride, bacterial mutants containing lesions in genes associated with resistance to antibiotics did not show fitness defects when RB-TnSeq libraries were exposed to exudates from the Δtmk3 mutant. Unexpectedly, exudates from wild-type T. atroviride and the Δtmk3 mutant rescued purine auxotrophic mutants of H. seropedicae, K. michiganensis and P. simiae. Metabolomic analysis on exudates from wild-type T. atroviride and the Δtmk3 mutant showed that both strains excrete purines and complex metabolites; functional Tmk3 is required to produce some of these metabolites. This study highlights the complex interplay between Trichoderma-metabolites and soil bacteria, revealing both beneficial and antagonistic effects, and underscoring the intricate and multifaceted nature of this relationship.
Collapse
Affiliation(s)
- José Manuel Villalobos-Escobedo
- Plant and Microbial Biology Department, The University of California, Berkeley, California, United States of America
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Maria Belen Mercado-Esquivias
- Plant and Microbial Biology Department, The University of California, Berkeley, California, United States of America
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Catharine Adams
- Plant and Microbial Biology Department, The University of California, Berkeley, California, United States of America
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - W. Berkeley Kauffman
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Rex R. Malmstrom
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Adam M. Deutschbauer
- Plant and Microbial Biology Department, The University of California, Berkeley, California, United States of America
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - N. Louise Glass
- Plant and Microbial Biology Department, The University of California, Berkeley, California, United States of America
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| |
Collapse
|
4
|
Case NT, Berman J, Blehert DS, Cramer RA, Cuomo C, Currie CR, Ene IV, Fisher MC, Fritz-Laylin LK, Gerstein AC, Glass NL, Gow NAR, Gurr SJ, Hittinger CT, Hohl TM, Iliev ID, James TY, Jin H, Klein BS, Kronstad JW, Lorch JM, McGovern V, Mitchell AP, Segre JA, Shapiro RS, Sheppard DC, Sil A, Stajich JE, Stukenbrock EE, Taylor JW, Thompson D, Wright GD, Heitman J, Cowen LE. The future of fungi: threats and opportunities. G3 (Bethesda) 2022; 12:jkac224. [PMID: 36179219 PMCID: PMC9635647 DOI: 10.1093/g3journal/jkac224] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/12/2022] [Indexed: 01/13/2023]
Abstract
The fungal kingdom represents an extraordinary diversity of organisms with profound impacts across animal, plant, and ecosystem health. Fungi simultaneously support life, by forming beneficial symbioses with plants and producing life-saving medicines, and bring death, by causing devastating diseases in humans, plants, and animals. With climate change, increased antimicrobial resistance, global trade, environmental degradation, and novel viruses altering the impact of fungi on health and disease, developing new approaches is now more crucial than ever to combat the threats posed by fungi and to harness their extraordinary potential for applications in human health, food supply, and environmental remediation. To address this aim, the Canadian Institute for Advanced Research (CIFAR) and the Burroughs Wellcome Fund convened a workshop to unite leading experts on fungal biology from academia and industry to strategize innovative solutions to global challenges and fungal threats. This report provides recommendations to accelerate fungal research and highlights the major research advances and ideas discussed at the meeting pertaining to 5 major topics: (1) Connections between fungi and climate change and ways to avert climate catastrophe; (2) Fungal threats to humans and ways to mitigate them; (3) Fungal threats to agriculture and food security and approaches to ensure a robust global food supply; (4) Fungal threats to animals and approaches to avoid species collapse and extinction; and (5) Opportunities presented by the fungal kingdom, including novel medicines and enzymes.
Collapse
Affiliation(s)
- Nicola T Case
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Judith Berman
- Shmunis School of Biomedical and Cancer Research, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - David S Blehert
- U.S. Geological Survey, National Wildlife Health Center, Madison, WI 53711, USA
| | - Robert A Cramer
- Department of Microbiology & Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Christina Cuomo
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Cameron R Currie
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Iuliana V Ene
- Department of Mycology, Institut Pasteur, Université de Paris, Paris 75015, France
| | - Matthew C Fisher
- MRC Centre for Global Infectious Disease Analysis, Imperial College, London W2 1PG, UK
| | | | - Aleeza C Gerstein
- Department of Microbiology and Department of Statistics, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - N Louise Glass
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720, USA
| | - Neil A R Gow
- Department of Biosciences, University of Exeter, Exeter EX4 4QD, UK
| | - Sarah J Gurr
- Department of Biosciences, University of Exeter, Exeter EX4 4QD, UK
| | - Chris Todd Hittinger
- Laboratory of Genetics, Center for Genomic Science Innovation, J.F. Crow Institute for the Study of Evolution, DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI 53726, USA
| | - Tobias M Hohl
- Infectious Disease Service, Department of Medicine, and Immunology Program, Sloan Kettering Institute, New York, NY 10065, USA
| | - Iliyan D Iliev
- Department of Microbiology and Immunology, Weill Cornell Medicine, New York, NY 10065, USA
| | - Timothy Y James
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Hailing Jin
- Department of Microbiology and Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California—Riverside, Riverside, CA 92507, USA
| | - Bruce S Klein
- Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin—Madison, Madison, WI 53706, USA
- Department of Internal Medicine, School of Medicine and Public Health, University of Wisconsin—Madison, Madison, WI 53706, USA
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin—Madison, Madison, WI 53706, USA
| | - James W Kronstad
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Jeffrey M Lorch
- U.S. Geological Survey, National Wildlife Health Center, Madison, WI 53711, USA
| | | | - Aaron P Mitchell
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Julia A Segre
- Microbial Genomics Section, Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Rebecca S Shapiro
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Donald C Sheppard
- McGill Interdisciplinary Initiative in Infection and Immunology, Departments of Medicine, Microbiology & Immunology, McGill University, Montreal, QC H3A 0G4, Canada
| | - Anita Sil
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94117, USA
| | - Jason E Stajich
- Department of Microbiology and Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California—Riverside, Riverside, CA 92507, USA
| | - Eva E Stukenbrock
- Max Planck Fellow Group Environmental Genomics, Max Planck Institute for Evolutionary Biology, Plön 24306, Germany
- Environmental Genomics, Christian-Albrechts University, Kiel 24118, Germany
| | - John W Taylor
- Department of Plant and Microbial Biology, University of California—Berkeley, Berkeley, CA 94720, USA
| | | | - Gerard D Wright
- M.G. DeGroote Institute for Infectious Disease Research, Department of Biochemistry and Biomedical Sciences, DeGroote School of Medicine, McMaster University, Hamilton, ON L8N 3Z5, Canada
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Medicine, and Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| |
Collapse
|
5
|
Cea-Sánchez S, Corrochano-Luque M, Gutiérrez G, Glass NL, Cánovas D, Corrochano LM. Transcriptional Regulation by the Velvet Protein VE-1 during Asexual Development in the Fungus Neurospora crassa. mBio 2022; 13:e0150522. [PMID: 35913159 PMCID: PMC9426599 DOI: 10.1128/mbio.01505-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 07/13/2022] [Indexed: 11/23/2022] Open
Abstract
Asexual reproduction in fungi facilitates the dispersal and colonization of new substrates and, in pathogenic fungi, allows infection of plants and animals. The velvet complex is a fungus-specific protein complex that participates in the regulation of gene expression in response to environmental signals like light, as well as developmental processes, pathogenesis, and secondary metabolism. The velvet complex in the fungus Neurospora crassa is composed of three proteins, VE-1, VE-2, and LAE-1. Mutations in ve-1 or ve-2, but not in lae-1, led to shorter heights of aerial tissue, a mixture of aerial hyphae and developing macroconidia, and increased microconidiation when they were combined with mutations in the transcription factor gene fl. VE-2 and LAE-1 were detected during vegetative growth and conidiation, unlike VE-1, which was mostly observed in samples obtained from submerged vegetative hyphae. We propose that VE-1 is the limiting component of the velvet complex during conidiation and has a major role in the transcriptional regulation of conidiation. Characterization of the role of VE-1 during mycelial growth and asexual development (conidiation) by transcriptome sequencing (RNA-seq) experiments allowed the identification of a set of genes regulated by VE-1 that participate in the regulation of conidiation, most notably the transcription factor genes vib-1 and fl. We propose that VE-1 and VE-2 regulate the development of aerial tissue and the balance between macro- and microconidiation in coordination with FL and VIB-1. IMPORTANCE Most fungi disperse in nature and infect new hosts by producing vegetative spores or conidia during asexual development. This is a process that is regulated by environmental signals like light and the availability of nutrients. A protein complex, the velvet complex, participates in the integration of environmental signals to regulate conidiation. We have found that a key component of this complex in the fungus Neurospora crassa, VE-1, has a major role in the regulation of transcription during conidiation. VE-1 regulates a large number of genes, including the genes for the transcription factors FL and VIB-1. Our results will help to understand how environmental signals are integrated in the fungal cell to regulate development.
Collapse
Affiliation(s)
- Sara Cea-Sánchez
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Seville, Spain
| | | | - Gabriel Gutiérrez
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Seville, Spain
| | - N. Louise Glass
- Plant and Microbial Biology Department, University of California, Berkeley, Berkeley, California, USA
| | - David Cánovas
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Seville, Spain
| | - Luis M. Corrochano
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Seville, Spain
| |
Collapse
|
6
|
Detomasi TC, Rico Ramírez AM, Sayler RI, Gonçalves AP, Marletta MA, Glass NL. A moonlighting function of a chitin polysaccharide monooxygenase, CWR-1, in Neurospora crassa allorecognition. eLife 2022; 11:80459. [PMID: 36040303 PMCID: PMC9550227 DOI: 10.7554/elife.80459] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Organisms require the ability to differentiate themselves from organisms of different or even the same species. Allorecognition processes in filamentous fungi are essential to ensure identity of an interconnected syncytial colony to protect it from exploitation and disease. Neurospora crassa has three cell fusion checkpoints controlling formation of an interconnected mycelial network. The locus that controls the second checkpoint, which allows for cell wall dissolution and subsequent fusion between cells/hyphae, cwr (cell wall remodeling), encodes two linked genes, cwr-1 and cwr-2. Previously, it was shown that cwr-1 and cwr-2 show severe linkage disequilibrium with six different haplogroups present in N. crassa populations. Isolates from an identical cwr haplogroup show robust fusion, while somatic cell fusion between isolates of different haplogroups is significantly blocked in cell wall dissolution. The cwr-1 gene encodes a putative polysaccharide monooxygenase (PMO). Herein we confirm that CWR-1 is a C1-oxidizing chitin PMO. We show that the catalytic (PMO) domain of CWR-1 was sufficient for checkpoint function and cell fusion blockage; however, through analysis of active-site, histidine-brace mutants, the catalytic activity of CWR-1 was ruled out as a major factor for allorecognition. Swapping a portion of the PMO domain (V86 to T130) did not switch cwr haplogroup specificity, but rather cells containing this chimera exhibited a novel haplogroup specificity. Allorecognition to mediate cell fusion blockage is likely occurring through a protein-protein interaction between CWR-1 with CWR-2. These data highlight a moonlighting role in allorecognition of the CWR-1 PMO domain.
Collapse
Affiliation(s)
- Tyler C Detomasi
- Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - Adriana M Rico Ramírez
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, United States
| | - Richard I Sayler
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, United States
| | | | - Michael A Marletta
- Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, United States
| |
Collapse
|
7
|
Rico-Ramírez AM, Pedro Gonçalves A, Louise Glass N. Fungal Cell Death: The Beginning of the End. Fungal Genet Biol 2022; 159:103671. [PMID: 35150840 DOI: 10.1016/j.fgb.2022.103671] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/04/2022] [Accepted: 01/29/2022] [Indexed: 11/04/2022]
Abstract
Death is an important part of an organism's existence and also marks the end of life. On a cellular level, death involves the execution of complex processes, which can be classified into different types depending on their characteristics. Despite their "simple" lifestyle, fungi carry out highly specialized and sophisticated mechanisms to regulate the way their cells die, and the pathways underlying these mechanisms are comparable with those of plants and metazoans. This review focuses on regulated cell death in fungi and discusses the evidence for the occurrence of apoptotic-like, necroptosis-like, pyroptosis-like death, and the role of the NLR proteins in fungal cell death. We also describe recent data on meiotic drive elements involved in "spore killing" and the molecular basis of allorecognition-related cell death during cell fusion of genetically dissimilar cells. Finally, we discuss how fungal regulated cell death can be relevant in developing strategies to avoid resistance and tolerance to antifungal agents.
Collapse
Affiliation(s)
- Adriana M Rico-Ramírez
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720
| | - A Pedro Gonçalves
- Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan City, 701, Taiwan
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720.
| |
Collapse
|
8
|
Abstract
A tripartite interaction between soil fungi, soil bacteria that produce phenazines that are toxic to the fungi, and a second bacterium that sequesters and detoxifies phenazines illustrates the complexity of antagonistic and mutualistic bacterial-fungal interactions.
Collapse
Affiliation(s)
- N Louise Glass
- The Plant and Microbial Biology Department, The University of California, Berkeley, CA 94720, USA; The Environmental Genomics and Systems Biology Division, The Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Adriana M Rico-Ramírez
- The Plant and Microbial Biology Department, The University of California, Berkeley, CA 94720, USA
| |
Collapse
|
9
|
Daskalov A, Glass NL. Gasdermin and Gasdermin-Like Pore-Forming Proteins in Invertebrates, Fungi and Bacteria. J Mol Biol 2021; 434:167273. [PMID: 34599942 DOI: 10.1016/j.jmb.2021.167273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 09/22/2021] [Accepted: 09/22/2021] [Indexed: 10/20/2022]
Abstract
The gasdermin family of pore-forming proteins (PFPs) has recently emerged as key molecular players controlling immune-related cell death in mammals. Characterized mammalian gasdermins are activated through proteolytic cleavage by caspases or serine proteases, which remove an inhibitory carboxy-terminal domain, allowing the pore-formation process. Processed gasdermins form transmembrane pores permeabilizing the plasma membrane, which often results in lytic and inflammatory cell death. While the gasdermin-dependent cell death (pyroptosis) has been predominantly characterized in mammals, it now has become clear that gasdermins also control cell death in early vertebrates (teleost fish) and invertebrate animals such as corals (Cnidaria). Moreover, gasdermins and gasdermin-like proteins have been identified and characterized in taxa outside of animals, notably Fungi and Bacteria. Fungal and bacterial gasdermins share many features with mammalian gasdermins including their mode of activation through proteolysis. It has been shown that in some cases the proteolytic activation is executed by evolutionarily related proteases acting downstream of proteins resembling immune receptors controlling pyroptosis in mammals. Overall, these findings establish gasdermins and gasdermin-regulated cell death as an extremely ancient mechanism of cellular suicide and build towards an understanding of the evolution of regulated cell death in the context of immunology. Here, we review the broader gasdermin family, focusing on recent discoveries in invertebrates, fungi and bacteria.
Collapse
Affiliation(s)
- Asen Daskalov
- Institut de Biochimie et Génétique Cellulaires, University of Bordeaux, France.
| | - N Louise Glass
- The Plant and Microbial Biology Department, The University of California, Berkeley, CA 94720-3102, United States
| |
Collapse
|
10
|
Qiao L, Lan C, Capriotti L, Ah-Fong A, Nino Sanchez J, Hamby R, Heller J, Zhao H, Glass NL, Judelson HS, Mezzetti B, Niu D, Jin H. Spray-induced gene silencing for disease control is dependent on the efficiency of pathogen RNA uptake. Plant Biotechnol J 2021; 19:1756-1768. [PMID: 33774895 DOI: 10.1101/2021.02.01.429265] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/01/2021] [Accepted: 03/06/2021] [Indexed: 05/21/2023]
Abstract
Recent discoveries show that fungi can take up environmental RNA, which can then silence fungal genes through environmental RNA interference. This discovery prompted the development of Spray-Induced Gene Silencing (SIGS) for plant disease management. In this study, we aimed to determine the efficacy of SIGS across a variety of eukaryotic microbes. We first examined the efficiency of RNA uptake in multiple pathogenic and non-pathogenic fungi, and an oomycete pathogen. We observed efficient double-stranded RNA (dsRNA) uptake in the fungal plant pathogens Botrytis cinerea, Sclerotinia sclerotiorum, Rhizoctonia solani, Aspergillus niger and Verticillium dahliae, but no uptake in Colletotrichum gloeosporioides, and weak uptake in a beneficial fungus, Trichoderma virens. For the oomycete plant pathogen, Phytophthora infestans, RNA uptake was limited and varied across different cell types and developmental stages. Topical application of dsRNA targeting virulence-related genes in pathogens with high RNA uptake efficiency significantly inhibited plant disease symptoms, whereas the application of dsRNA in pathogens with low RNA uptake efficiency did not suppress infection. Our results have revealed that dsRNA uptake efficiencies vary across eukaryotic microbe species and cell types. The success of SIGS for plant disease management can largely be determined by the pathogen's RNA uptake efficiency.
Collapse
Affiliation(s)
- Lulu Qiao
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), Nanjing, China
- Department of Microbiology & Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Chi Lan
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), Nanjing, China
| | - Luca Capriotti
- Department of Microbiology & Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | - Audrey Ah-Fong
- Department of Microbiology & Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Jonatan Nino Sanchez
- Department of Microbiology & Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Rachael Hamby
- Department of Microbiology & Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Jens Heller
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
- Environmental Genomics and Systems Biology Division, The Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Hongwei Zhao
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), Nanjing, China
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
- Environmental Genomics and Systems Biology Division, The Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Howard S Judelson
- Department of Microbiology & Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Bruno Mezzetti
- Department of Microbiology & Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | - Dongdong Niu
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), Nanjing, China
- Department of Microbiology & Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Hailing Jin
- Department of Microbiology & Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
| |
Collapse
|
11
|
Qiao L, Lan C, Capriotti L, Ah‐Fong A, Nino Sanchez J, Hamby R, Heller J, Zhao H, Glass NL, Judelson HS, Mezzetti B, Niu D, Jin H. Spray-induced gene silencing for disease control is dependent on the efficiency of pathogen RNA uptake. Plant Biotechnol J 2021; 19:1756-1768. [PMID: 33774895 PMCID: PMC8428832 DOI: 10.1111/pbi.13589] [Citation(s) in RCA: 97] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/01/2021] [Accepted: 03/06/2021] [Indexed: 05/20/2023]
Abstract
Recent discoveries show that fungi can take up environmental RNA, which can then silence fungal genes through environmental RNA interference. This discovery prompted the development of Spray-Induced Gene Silencing (SIGS) for plant disease management. In this study, we aimed to determine the efficacy of SIGS across a variety of eukaryotic microbes. We first examined the efficiency of RNA uptake in multiple pathogenic and non-pathogenic fungi, and an oomycete pathogen. We observed efficient double-stranded RNA (dsRNA) uptake in the fungal plant pathogens Botrytis cinerea, Sclerotinia sclerotiorum, Rhizoctonia solani, Aspergillus niger and Verticillium dahliae, but no uptake in Colletotrichum gloeosporioides, and weak uptake in a beneficial fungus, Trichoderma virens. For the oomycete plant pathogen, Phytophthora infestans, RNA uptake was limited and varied across different cell types and developmental stages. Topical application of dsRNA targeting virulence-related genes in pathogens with high RNA uptake efficiency significantly inhibited plant disease symptoms, whereas the application of dsRNA in pathogens with low RNA uptake efficiency did not suppress infection. Our results have revealed that dsRNA uptake efficiencies vary across eukaryotic microbe species and cell types. The success of SIGS for plant disease management can largely be determined by the pathogen's RNA uptake efficiency.
Collapse
Affiliation(s)
- Lulu Qiao
- College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education)NanjingChina
- Department of Microbiology & Plant PathologyCenter for Plant Cell BiologyInstitute for Integrative Genome BiologyUniversity of CaliforniaRiversideCAUSA
| | - Chi Lan
- College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education)NanjingChina
| | - Luca Capriotti
- Department of Microbiology & Plant PathologyCenter for Plant Cell BiologyInstitute for Integrative Genome BiologyUniversity of CaliforniaRiversideCAUSA
- Department of Agricultural, Food and Environmental SciencesMarche Polytechnic UniversityAnconaItaly
| | - Audrey Ah‐Fong
- Department of Microbiology & Plant PathologyCenter for Plant Cell BiologyInstitute for Integrative Genome BiologyUniversity of CaliforniaRiversideCAUSA
| | - Jonatan Nino Sanchez
- Department of Microbiology & Plant PathologyCenter for Plant Cell BiologyInstitute for Integrative Genome BiologyUniversity of CaliforniaRiversideCAUSA
| | - Rachael Hamby
- Department of Microbiology & Plant PathologyCenter for Plant Cell BiologyInstitute for Integrative Genome BiologyUniversity of CaliforniaRiversideCAUSA
| | - Jens Heller
- Department of Plant and Microbial BiologyUniversity of CaliforniaBerkeleyCAUSA
- Environmental Genomics and Systems Biology DivisionThe Lawrence Berkeley National LaboratoryBerkeleyCAUSA
| | - Hongwei Zhao
- College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education)NanjingChina
| | - N. Louise Glass
- Department of Plant and Microbial BiologyUniversity of CaliforniaBerkeleyCAUSA
- Environmental Genomics and Systems Biology DivisionThe Lawrence Berkeley National LaboratoryBerkeleyCAUSA
| | - Howard S. Judelson
- Department of Microbiology & Plant PathologyCenter for Plant Cell BiologyInstitute for Integrative Genome BiologyUniversity of CaliforniaRiversideCAUSA
| | - Bruno Mezzetti
- Department of Microbiology & Plant PathologyCenter for Plant Cell BiologyInstitute for Integrative Genome BiologyUniversity of CaliforniaRiversideCAUSA
- Department of Agricultural, Food and Environmental SciencesMarche Polytechnic UniversityAnconaItaly
| | - Dongdong Niu
- College of Plant ProtectionNanjing Agricultural UniversityNanjingChina
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education)NanjingChina
- Department of Microbiology & Plant PathologyCenter for Plant Cell BiologyInstitute for Integrative Genome BiologyUniversity of CaliforniaRiversideCAUSA
| | - Hailing Jin
- Department of Microbiology & Plant PathologyCenter for Plant Cell BiologyInstitute for Integrative Genome BiologyUniversity of CaliforniaRiversideCAUSA
| |
Collapse
|
12
|
Huberman LB, Wu VW, Kowbel DJ, Lee J, Daum C, Grigoriev IV, O'Malley RC, Glass NL. DNA affinity purification sequencing and transcriptional profiling reveal new aspects of nitrogen regulation in a filamentous fungus. Proc Natl Acad Sci U S A 2021; 118:e2009501118. [PMID: 33753477 PMCID: PMC8020665 DOI: 10.1073/pnas.2009501118] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sensing available nutrients and efficiently utilizing them is a challenge common to all organisms. The model filamentous fungus Neurospora crassa is capable of utilizing a variety of inorganic and organic nitrogen sources. Nitrogen utilization in N. crassa is regulated by a network of pathway-specific transcription factors that activate genes necessary to utilize specific nitrogen sources in combination with nitrogen catabolite repression regulatory proteins. We identified an uncharacterized pathway-specific transcription factor, amn-1, that is required for utilization of the nonpreferred nitrogen sources proline, branched-chain amino acids, and aromatic amino acids. AMN-1 also plays a role in regulating genes involved in responding to the simple sugar mannose, suggesting an integration of nitrogen and carbon metabolism. The utilization of nonpreferred nitrogen sources, which require metabolic processing before being used as a nitrogen source, is also regulated by the nitrogen catabolite regulator NIT-2. Using RNA sequencing combined with DNA affinity purification sequencing, we performed a survey of the role of NIT-2 and the pathway-specific transcription factors NIT-4 and AMN-1 in directly regulating genes involved in nitrogen utilization. Although previous studies suggested promoter binding by both a pathway-specific transcription factor and NIT-2 may be necessary for activation of nitrogen-responsive genes, our data show that pathway-specific transcription factors regulate genes involved in the catabolism of specific nitrogen sources, while NIT-2 regulates genes involved in utilization of all nonpreferred nitrogen sources, such as nitrogen transporters. Together, these transcription factors form a nutrient sensing network that allows N. crassa cells to regulate nitrogen utilization.
Collapse
Affiliation(s)
- Lori B Huberman
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720;
- Energy Biosciences Institute, University of California, Berkeley, CA 94720
| | - Vincent W Wu
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720
- Energy Biosciences Institute, University of California, Berkeley, CA 94720
| | - David J Kowbel
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720
| | - Juna Lee
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Chris Daum
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Igor V Grigoriev
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Ronan C O'Malley
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - N Louise Glass
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720;
- Energy Biosciences Institute, University of California, Berkeley, CA 94720
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| |
Collapse
|
13
|
Abstract
Filamentous fungi typically grow as interconnected multinucleate syncytia that can be microscopic to many hectares in size. Mechanistic details and rules that govern the formation and function of these multinucleate syncytia are largely unexplored, including details on syncytial morphology and the regulatory controls of cellular and molecular processes. Recent discoveries have revealed various adaptations that enable fungal syncytia to accomplish coordinated behaviors, including cell growth, nuclear division, secretion, communication, and adaptation of the hyphal network for mixing nuclear and cytoplasmic organelles. In this review, we highlight recent studies using advanced technologies to define rules that govern organizing principles of hyphal and colony differentiation, including various aspects of nuclear and mitochondrial cooperation versus competition. We place these findings into context with previous foundational literature and present still unanswered questions on mechanistic aspects, function, and morphological diversity of fungal syncytia across the fungal kingdom.
Collapse
Affiliation(s)
- Alexander P. Mela
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA; (A.P.M.); (A.M.R.-R.)
| | - Adriana M. Rico-Ramírez
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA; (A.P.M.); (A.M.R.-R.)
| | - N. Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA; (A.P.M.); (A.M.R.-R.)
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Correspondence:
| |
Collapse
|
14
|
Gonçalves AP, Heller J, Rico-Ramírez AM, Daskalov A, Rosenfield G, Glass NL. Conflict, Competition, and Cooperation Regulate Social Interactions in Filamentous Fungi. Annu Rev Microbiol 2020; 74:693-712. [PMID: 32689913 DOI: 10.1146/annurev-micro-012420-080905] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Social cooperation impacts the development and survival of species. In higher taxa, kin recognition occurs via visual, chemical, or tactile cues that dictate cooperative versus competitive interactions. In microbes, the outcome of cooperative versus competitive interactions is conferred by identity at allorecognition loci, so-called kind recognition. In syncytial filamentous fungi, the acquisition of multicellularity is associated with somatic cell fusion within and between colonies. However, such intraspecific cooperation entails risks, as fusion can transmit deleterious genotypes or infectious components that reduce fitness, or give rise to cheaters that can exploit communal goods without contributing to their production. Allorecognition mechanisms in syncytial fungi regulate somatic cell fusion by operating precontact during chemotropic interactions, during cell adherence, and postfusion by triggering programmed cell death reactions. Alleles at fungal allorecognition loci are highly polymorphic, fall into distinct haplogroups, and show evolutionary signatures of balancing selection, similar to allorecognition loci across the tree of life.
Collapse
Affiliation(s)
- A Pedro Gonçalves
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA.,Current Affiliation: Institute of Molecular Biology, Academia Sinica, Nangang District, Taipei 115, Taiwan
| | - Jens Heller
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA.,Current Affiliation: Perfect Day, Inc., Emeryville, California 94608, USA
| | - Adriana M Rico-Ramírez
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA
| | - Asen Daskalov
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA.,Current Affiliation: Institut Européen de Chimie et Biologie, 33600 Pessac, France
| | - Gabriel Rosenfield
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA.,Current Affiliation: Department of Genetics, Stanford University School of Medicine, Stanford, California 94305, USA
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA.,Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| |
Collapse
|
15
|
Drott MT, Satterlee TR, Skerker JM, Pfannenstiel BT, Glass NL, Keller NP, Milgroom MG. The Frequency of Sex: Population Genomics Reveals Differences in Recombination and Population Structure of the Aflatoxin-Producing Fungus Aspergillus flavus. mBio 2020; 11:e00963-20. [PMID: 32665272 PMCID: PMC7360929 DOI: 10.1128/mbio.00963-20] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 06/18/2020] [Indexed: 11/20/2022] Open
Abstract
The apparent rarity of sex in many fungal species has raised questions about how much sex is needed to purge deleterious mutations and how differences in frequency of sex impact fungal evolution. We sought to determine how differences in the extent of recombination between populations of Aspergillus flavus impact the evolution of genes associated with the synthesis of aflatoxin, a notoriously potent carcinogen. We sequenced the genomes of, and quantified aflatoxin production in, 94 isolates of A. flavus sampled from seven states in eastern and central latitudinal transects of the United States. The overall population is subdivided into three genetically differentiated populations (A, B, and C) that differ greatly in their extent of recombination, diversity, and aflatoxin-producing ability. Estimates of the number of recombination events and linkage disequilibrium decay suggest relatively frequent sex only in population A. Population B is sympatric with population A but produces significantly less aflatoxin and is the only population where the inability of nonaflatoxigenic isolates to produce aflatoxin was explained by multiple gene deletions. Population expansion evident in population B suggests a recent introduction or range expansion. Population C is largely nonaflatoxigenic and restricted mainly to northern sampling locations through restricted migration and/or selection. Despite differences in the number and type of mutations in the aflatoxin gene cluster, codon optimization and site frequency differences in synonymous and nonsynonymous mutations suggest that low levels of recombination in some A. flavus populations are sufficient to purge deleterious mutations.IMPORTANCE Differences in the relative frequencies of sexual and asexual reproduction have profound implications for the accumulation of deleterious mutations (Muller's ratchet), but little is known about how these differences impact the evolution of ecologically important phenotypes. Aspergillus flavus is the main producer of aflatoxin, a notoriously potent carcinogen that often contaminates food. We investigated if differences in the levels of production of aflatoxin by A. flavus could be explained by the accumulation of deleterious mutations due to a lack of recombination. Despite differences in the extent of recombination, variation in aflatoxin production is better explained by the demography and history of specific populations and may suggest important differences in the ecological roles of aflatoxin among populations. Furthermore, the association of aflatoxin production and populations provides a means of predicting the risk of aflatoxin contamination by determining the frequencies of isolates from low- and high-production populations.
Collapse
Affiliation(s)
- Milton T Drott
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Tatum R Satterlee
- Department of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Jeffrey M Skerker
- Innovative Genomics Institute, The University of California, Berkeley, California, USA
| | | | - N Louise Glass
- Innovative Genomics Institute, The University of California, Berkeley, California, USA
- Department of Plant and Microbial Biology, The University of California, Berkeley, California, USA
- Environmental Genomics and Systems Biology, The Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Michael G Milgroom
- School of Integrative Plant Science, Plant Pathology and Plant-Microbe Biology Section, Cornell University, Ithaca, New York, USA
| |
Collapse
|
16
|
Wu VW, Thieme N, Huberman LB, Dietschmann A, Kowbel DJ, Lee J, Calhoun S, Singan VR, Lipzen A, Xiong Y, Monti R, Blow MJ, O'Malley RC, Grigoriev IV, Benz JP, Glass NL. The regulatory and transcriptional landscape associated with carbon utilization in a filamentous fungus. Proc Natl Acad Sci U S A 2020; 117:6003-6013. [PMID: 32111691 PMCID: PMC7084071 DOI: 10.1073/pnas.1915611117] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Filamentous fungi, such as Neurospora crassa, are very efficient in deconstructing plant biomass by the secretion of an arsenal of plant cell wall-degrading enzymes, by remodeling metabolism to accommodate production of secreted enzymes, and by enabling transport and intracellular utilization of plant biomass components. Although a number of enzymes and transcriptional regulators involved in plant biomass utilization have been identified, how filamentous fungi sense and integrate nutritional information encoded in the plant cell wall into a regulatory hierarchy for optimal utilization of complex carbon sources is not understood. Here, we performed transcriptional profiling of N. crassa on 40 different carbon sources, including plant biomass, to provide data on how fungi sense simple to complex carbohydrates. From these data, we identified regulatory factors in N. crassa and characterized one (PDR-2) associated with pectin utilization and one with pectin/hemicellulose utilization (ARA-1). Using in vitro DNA affinity purification sequencing (DAP-seq), we identified direct targets of transcription factors involved in regulating genes encoding plant cell wall-degrading enzymes. In particular, our data clarified the role of the transcription factor VIB-1 in the regulation of genes encoding plant cell wall-degrading enzymes and nutrient scavenging and revealed a major role of the carbon catabolite repressor CRE-1 in regulating the expression of major facilitator transporter genes. These data contribute to a more complete understanding of cross talk between transcription factors and their target genes, which are involved in regulating nutrient sensing and plant biomass utilization on a global level.
Collapse
Affiliation(s)
- Vincent W Wu
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
- Energy Biosciences Institute, University of California, Berkeley, CA 94704
| | - Nils Thieme
- Holzforschung München, Technical University of Munich School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Lori B Huberman
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
- Energy Biosciences Institute, University of California, Berkeley, CA 94704
| | - Axel Dietschmann
- Holzforschung München, Technical University of Munich School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - David J Kowbel
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
| | - Juna Lee
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Sara Calhoun
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Vasanth R Singan
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Yi Xiong
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
- Energy Biosciences Institute, University of California, Berkeley, CA 94704
| | - Remo Monti
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Matthew J Blow
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Ronan C O'Malley
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Igor V Grigoriev
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - J Philipp Benz
- Holzforschung München, Technical University of Munich School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720;
- Energy Biosciences Institute, University of California, Berkeley, CA 94704
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| |
Collapse
|
17
|
Gonçalves AP, Glass NL. Fungal social barriers: to fuse, or not to fuse, that is the question. Commun Integr Biol 2020; 13:39-42. [PMID: 32313605 PMCID: PMC7159315 DOI: 10.1080/19420889.2020.1740554] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 03/02/2020] [Accepted: 03/02/2020] [Indexed: 12/15/2022] Open
Abstract
Cell fusion takes place in all domains of life and contributes greatly to the formation of complex multicellular structures. In particular, many fungi, such as the filamentous Neurospora crassa, rely on conspecific somatic cell fusion to drive the unicellular-to-multicellular transition and formation of the interconnected mycelial syncytium. This can, however, lead to the transmission of infectious elements and deleterious genotypes that have a negative impact on the organismal fitness. Accumulating evidence obtained from natural populations suggests that N. crassa has evolved various self/non-self or allorecognition systems to avoid fusion between genetically non-identical spores or hyphae at all costs. Here we present an overview of the recent advances made in the field of fungal allorecognition, describe its genetic basis, and comment on its evolutionary meaning. These data pinpoint the multilayered complexity of the cooperative social behaviors undertaken by a model eukaryotic microbe.
Collapse
Affiliation(s)
- A Pedro Gonçalves
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.,Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| |
Collapse
|
18
|
Gonçalves AP, Chow KM, Cea-Sánchez S, Glass NL. WHI-2 Regulates Intercellular Communication via a MAP Kinase Signaling Complex. Front Microbiol 2020; 10:3162. [PMID: 32038591 PMCID: PMC6987382 DOI: 10.3389/fmicb.2019.03162] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 12/31/2019] [Indexed: 01/15/2023] Open
Abstract
The formation of the fungal mycelial network is facilitated by somatic cell fusion of germinating asexual spores (or germlings). Neurospora crassa germlings in close proximity display chemotropic growth that is dependent upon an intracellular network of mitogen-activated protein kinase (MAPK) signaling cascades. Approximately 80 genes involved in intercellular communication and fusion have been identified, including three mutants with similar morphological phenotypes: Δwhi-2, Δcsp-6, and Δamph-1. Here we show that WHI-2 localizes to the cell periphery and regulates endocytosis, mitochondrial organization, sporulation, and cell fusion. WHI-2 was required to transduce signals through a conserved MAPK pathway (NRC-1/MEK-2/MAK-2) and target transcription factors (PP-1/ADV-1). The amph-1 locus encodes a Bin/Amphiphysin/Rvs domain-containing protein and mis-expression of whi-2 compensated for the cell fusion and endocytosis deficiencies of a Δamph-1 mutant. The csp-6 locus encodes a haloacid dehalogenase phosphatase whose activity was essential for cell fusion. Although fusion-deficient with themselves, cells that lacked whi-2, csp-6, or amph-1 showed a low frequency of chemotropic interactions with wild type cells. We hypothesize that WHI-2 could be important for signal perception during chemotropic interactions via a role in endocytosis.
Collapse
Affiliation(s)
- A Pedro Gonçalves
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, United States
| | - Karen M Chow
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, United States
| | - Sara Cea-Sánchez
- Departamento de Genética, Universidad de Sevilla, Sevilla, Spain
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, United States.,Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| |
Collapse
|
19
|
Gonçalves AP, McCluskey K, Glass NL, Videira A. The Fungal Cell Death Regulator czt-1 Is Allelic to acr-3. J Fungi (Basel) 2019; 5:jof5040114. [PMID: 31817728 PMCID: PMC6958467 DOI: 10.3390/jof5040114] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/04/2019] [Accepted: 12/04/2019] [Indexed: 01/24/2023] Open
Abstract
Fungal infections have far-reaching implications that range from severe human disease to a panoply of disruptive agricultural and ecological effects, making it imperative to identify and understand the molecular pathways governing the response to antifungal compounds. In this context, CZT-1 (cell death-activated zinc cluster transcription factor) functions as a master regulator of cell death and drug susceptibility in Neurospora crassa. Here we provide evidence indicating that czt-1 is allelic to acr-3, a previously described locus that we now found to harbor a point mutation in its coding sequence. This nonsynonymous amino acid substitution in a low complexity region of CZT-1/ACR-3 caused a robust gain-of-function that led to reduced sensitivity to acriflavine and staurosporine, and increased expression of the drug efflux pump abc-3. Thus, accumulating evidence shows that CZT-1 is an important broad regulator of the cellular response to various antifungal compounds that appear to share common molecular targets.
Collapse
Affiliation(s)
- A. Pedro Gonçalves
- ICBAS-Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
- Correspondence:
| | - Kevin McCluskey
- Fungal Genetics Stock Center, Department of Plant Pathology, Kansas State University, 4024 Throckmorton Plant Sciences Center, Manhattan, KS 66506, USA
| | - N. Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - Arnaldo Videira
- ICBAS-Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
- i3S—Institute for Research and Innovation in Health, University of Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| |
Collapse
|
20
|
Daskalov A, Gladieux P, Heller J, Glass NL. Programmed Cell Death in Neurospora crassa Is Controlled by the Allorecognition Determinant rcd-1. Genetics 2019; 213:1387-1400. [PMID: 31636083 PMCID: PMC6893366 DOI: 10.1534/genetics.119.302617] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Accepted: 10/17/2019] [Indexed: 12/31/2022] Open
Abstract
Nonself recognition following cell fusion between genetically distinct individuals of the same species in filamentous fungi often results in a programmed cell death (PCD) reaction, where the heterokaryotic fusion cell is compartmentalized and rapidly killed. The allorecognition process plays a key role as a defense mechanism that restricts genome exploitation, resource plundering, and the spread of deleterious senescence plasmids and mycoviruses. Although a number of incompatibility systems have been described that function in mature hyphae, less is known about the PCD pathways in asexual spores, which represent the main infectious unit in various human and plant fungal pathogens. Here, we report the identification of regulator of cell death-1 (rcd-1), a novel allorecognition gene, controlling PCD in germinating asexual spores of Neurospora crassa; rcd-1 is one of the most polymorphic genes in the genomes of wild N. crassa isolates. The coexpression of two antagonistic rcd-1-1 and rcd-1-2 alleles was necessary and sufficient to trigger cell death in fused germlings and in hyphae. Based on analysis of wild populations of N. crassa and N. discreta, rcd-1 alleles appeared to be under balancing selection and associated with trans-species polymorphisms. We shed light on genomic rearrangements that could have led to the emergence of the incompatibility system in Neurospora and show that rcd-1 belongs to a much larger gene family in fungi. Overall, our work contributes toward a better understanding of allorecognition and PCD in an underexplored developmental stage of filamentous fungi.
Collapse
Affiliation(s)
- Asen Daskalov
- Plant and Microbial Biology Department, The University of California, Berkeley, California 94720
| | - Pierre Gladieux
- UMR BGPI, INRA, CIRAD, Montpellier SupAgro, University Montpellier, 34060, France
| | - Jens Heller
- Plant and Microbial Biology Department, The University of California, Berkeley, California 94720
- Environmental Genomics and Systems Biology Division, The Lawrence Berkeley National Laboratory, California 94720
| | - N Louise Glass
- Plant and Microbial Biology Department, The University of California, Berkeley, California 94720
- Environmental Genomics and Systems Biology Division, The Lawrence Berkeley National Laboratory, California 94720
| |
Collapse
|
21
|
Feldman D, Kowbel DJ, Cohen A, Glass NL, Hadar Y, Yarden O. Identification and manipulation of Neurospora crassa genes involved in sensitivity to furfural. Biotechnol Biofuels 2019; 12:210. [PMID: 31508149 PMCID: PMC6724289 DOI: 10.1186/s13068-019-1550-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 08/24/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Biofuels derived from lignocellulosic biomass are a viable alternative to fossil fuels required for transportation. Following plant biomass pretreatment, the furan derivative furfural is present at concentrations which are inhibitory to yeasts. Detoxification of furfural is thus important for efficient fermentation. Here, we searched for new genetic attributes in the fungus Neurospora crassa that may be linked to furfural tolerance. The fact that furfural is involved in the natural process of sexual spore germination of N. crassa and that this fungus is highly amenable to genetic manipulations makes it a rational candidate for this study. RESULTS Both hypothesis-based and unbiased (random promotor mutagenesis) approaches were performed to identify N. crassa genes associated with the response to furfural. Changes in the transcriptional profile following exposure to furfural revealed that the affected processes were, overall, similar to those observed in Saccharomyces cerevisiae. N. crassa was more tolerant (by ~ 30%) to furfural when carboxymethyl cellulose was the main carbon source as opposed to sucrose, indicative of a link between carbohydrate metabolism and furfural tolerance. We also observed increased tolerance in a Δcre-1 mutant (CRE-1 is a key transcription factor that regulates the ability of fungi to utilize non-preferred carbon sources). In addition, analysis of aldehyde dehydrogenase mutants showed that ahd-2 (NCU00378) was involved in tolerance to furfural as well as the predicted membrane transporter NCU05580 (flr-1), a homolog of FLR1 in S. cerevisiae. Further to the rational screening, an unbiased approach revealed additional genes whose inactivation conferred increased tolerance to furfural: (i) NCU02488, which affected the abundance of the non-anchored cell wall protein NCW-1 (NCU05137), and (ii) the zinc finger protein NCU01407. CONCLUSIONS We identified attributes in N. crassa associated with tolerance or degradation of furfural, using complementary research approaches. The manipulation of the genes involved in furan sensitivity can provide a means for improving the production of biofuel producing strains. Similar research approaches can be utilized in N. crassa and other filamentous fungi to identify additional attributes relevant to other furans or toxic chemicals.
Collapse
Affiliation(s)
- Daria Feldman
- Department of Plant Pathology and Microbiology, The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, 7600001 Rehovot, Israel
| | - David J. Kowbel
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720 USA
| | - Adi Cohen
- Department of Plant Pathology and Microbiology, The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, 7600001 Rehovot, Israel
| | - N. Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720 USA
- Environmental Genomics and Systems Biology Division, The Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 USA
| | - Yitzhak Hadar
- Department of Plant Pathology and Microbiology, The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, 7600001 Rehovot, Israel
| | - Oded Yarden
- Department of Plant Pathology and Microbiology, The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, 7600001 Rehovot, Israel
| |
Collapse
|
22
|
Fischer MS, Glass NL. Communicate and Fuse: How Filamentous Fungi Establish and Maintain an Interconnected Mycelial Network. Front Microbiol 2019; 10:619. [PMID: 31001214 PMCID: PMC6455062 DOI: 10.3389/fmicb.2019.00619] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 03/12/2019] [Indexed: 12/22/2022] Open
Abstract
Cell-to-cell communication and cell fusion are fundamental biological processes across the tree of life. Survival is often dependent upon being able to identify nearby individuals and respond appropriately. Communication between genetically different individuals allows for the identification of potential mating partners, symbionts, prey, or predators. In contrast, communication between genetically similar (or identical) individuals is important for mediating the development of multicellular organisms or for coordinating density-dependent behaviors (i.e., quorum sensing). This review describes the molecular and genetic mechanisms that mediate cell-to-cell communication and cell fusion between cells of Ascomycete filamentous fungi, with a focus on Neurospora crassa. Filamentous fungi exist as a multicellular, multinuclear network of hyphae, and communication-mediated cell fusion is an important aspect of colony development at each stage of the life cycle. Asexual spore germination occurs in a density-dependent manner. Germinated spores (germlings) avoid cells that are genetically different at specific loci, while chemotropically engaging with cells that share identity at these recognition loci. Germlings with genetic identity at recognition loci undergo cell fusion when in close proximity, a fitness attribute that contributes to more rapid colony establishment. Communication and cell fusion also occur between hyphae in a colony, which are important for reinforcing colony architecture and supporting the development of complex structures such as aerial hyphae and sexual reproductive structures. Over 70 genes have been identified in filamentous fungi (primarily N. crassa) that are involved in kind recognition, chemotropic interactions, and cell fusion. While the hypothetical signal(s) and receptor(s) remain to be described, a dynamic molecular signaling network that regulates cell-cell interactions has been revealed, including two conserved MAP-Kinase cascades, a conserved STRIPAK complex, transcription factors, a NOX complex involved in the generation of reactive oxygen species, cell-integrity sensors, actin, components of the secretory pathway, and several other proteins. Together these pathways facilitate the integration of extracellular signals, direct polarized growth, and initiate a transcriptional program that reinforces signaling and prepares cells for downstream processes, such as membrane merger, cell fusion and adaptation to heterokaryon formation.
Collapse
Affiliation(s)
- Monika S. Fischer
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley CA, United States
| | - N. Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley CA, United States
- Environmental Genomics and Systems Biology Division, The Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| |
Collapse
|
23
|
Riquelme M, Aime MC, Branco S, Brand A, Brown A, Glass NL, Kahmann R, Momany M, Rokas A, Trail F. The power of discussion: Support for women at the fungal Gordon Research Conference. Fungal Genet Biol 2018; 121:65-67. [PMID: 30261275 DOI: 10.1016/j.fgb.2018.09.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 09/21/2018] [Indexed: 10/28/2022]
Affiliation(s)
- Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y Educación Superior de Ensenada (CICESE), Ctra. Ensenada-Tijuana No. 3918, Ensenada, Baja California 22860, Mexico.
| | - M Catherine Aime
- Dept. Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA
| | - Sara Branco
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, 59717, USA
| | - Alexandra Brand
- MRC Centre for Medical Mycology, University of Aberdeen, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, Foresterhill, Aberdeen, Aberdeenshire AB25 2ZD, United Kingdom
| | - Alistair Brown
- Aberdeen Fungal Group, University of Aberdeen, Department of Molecular and Cell Biology, Institute of Medical Sciences, Aberdeen AB25 2ZD, UK
| | - N Louise Glass
- The Plant and Microbial Biology Department, University of California, Berkeley, CA 94720-3102, USA
| | - Regine Kahmann
- Max Planck Institute for Terrestrial Microbiology, D-35043 Marburg, Germany
| | - Michelle Momany
- Fungal Biology Group and Department of Plant Biology, University of Georgia, Athens, GA, USA
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Frances Trail
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824-1312, USA
| |
Collapse
|
24
|
Matsu-ura T, Dovzhenok AA, Coradetti ST, Subramanian KR, Meyer DR, Kwon JJ, Kim C, Salomonis N, Glass NL, Lim S, Hong CI. Synthetic Gene Network with Positive Feedback Loop Amplifies Cellulase Gene Expression in Neurospora crassa. ACS Synth Biol 2018; 7:1395-1405. [PMID: 29625007 DOI: 10.1021/acssynbio.8b00011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Second-generation or lignocellulosic biofuels are a tangible source of renewable energy, which is critical to combat climate change by reducing the carbon footprint. Filamentous fungi secrete cellulose-degrading enzymes called cellulases, which are used for production of lignocellulosic biofuels. However, inefficient production of cellulases is a major obstacle for industrial-scale production of second-generation biofuels. We used computational simulations to design and implement synthetic positive feedback loops to increase gene expression of a key transcription factor, CLR-2, that activates a large number of cellulases in a filamentous fungus, Neurospora crassa. Overexpression of CLR-2 reveals previously unappreciated roles of CLR-2 in lignocellulosic gene network, which enabled simultaneous induction of approximately 50% of 78 lignocellulosic degradation-related genes in our engineered Neurospora strains. This engineering results in dramatically increased cellulase activity due to cooperative orchestration of multiple enzymes involved in the cellulose degradation pathway. Our work provides a proof of principle in utilizing mathematical modeling and synthetic biology to improve the efficiency of cellulase synthesis for second-generation biofuel production.
Collapse
Affiliation(s)
- Toru Matsu-ura
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio 45267-0529, United States
| | - Andrey A. Dovzhenok
- Department of Mathematical Sciences, University of Cincinnati, Cincinnati, Ohio 45221-0025, United States
| | - Samuel T. Coradetti
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, United States
| | - Krithika R. Subramanian
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio 45267-0529, United States
- Department of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio 45229-3039, United States
| | - Daniel R. Meyer
- Department of Biomedical, Chemical, and Environmental Engineering, University of Cincinnati, Cincinnati, Ohio 45221-0012, United States
| | - Jaesang J. Kwon
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio 45267-0529, United States
| | - Caleb Kim
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio 45267-0529, United States
| | - Nathan Salomonis
- Department of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio 45229-3039, United States
- Division of Developmental Biology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio 45229-3039, United States
| | - N. Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, United States
| | - Sookkyung Lim
- Department of Mathematical Sciences, University of Cincinnati, Cincinnati, Ohio 45221-0025, United States
| | - Christian I. Hong
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio 45267-0529, United States
- Division of Developmental Biology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio 45229-3039, United States
| |
Collapse
|
25
|
Starr TL, Gonçalves AP, Meshgin N, Glass NL. The major cellulases CBH-1 and CBH-2 of Neurospora crassa rely on distinct ER cargo adaptors for efficient ER-exit. Mol Microbiol 2017; 107:229-248. [PMID: 29131484 DOI: 10.1111/mmi.13879] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2017] [Indexed: 12/17/2022]
Abstract
Filamentous fungi are native secretors of lignocellulolytic enzymes and are used as protein-producing factories in the industrial biotechnology sector. Despite the importance of these organisms in industry, relatively little is known about the filamentous fungal secretory pathway or how it might be manipulated for improved protein production. Here, we use Neurospora crassa as a model filamentous fungus to interrogate the requirements for trafficking of cellulase enzymes from the endoplasmic reticulum to the Golgi. We characterized the localization and interaction properties of the p24 and ERV-29 cargo adaptors, as well as their role in cellulase enzyme trafficking. We find that the two most abundantly secreted cellulases, CBH-1 and CBH-2, depend on distinct ER cargo adaptors for efficient exit from the ER. CBH-1 depends on the p24 proteins, whereas CBH-2 depends on the N. crassa homolog of yeast Erv29p. This study provides a first step in characterizing distinct trafficking pathways of lignocellulolytic enzymes in filamentous fungi.
Collapse
Affiliation(s)
- Trevor L Starr
- The Energy Biosciences Institute, The University of California, Berkeley, CA 94720, USA
| | - A Pedro Gonçalves
- The Energy Biosciences Institute, The University of California, Berkeley, CA 94720, USA.,Plant and Microbial Biology Department, The University of California, Berkeley, CA 94720, USA
| | - Neeka Meshgin
- The Energy Biosciences Institute, The University of California, Berkeley, CA 94720, USA
| | - N Louise Glass
- The Energy Biosciences Institute, The University of California, Berkeley, CA 94720, USA.,Plant and Microbial Biology Department, The University of California, Berkeley, CA 94720, USA.,Environmental Genomics and Systems Biology Division, The Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| |
Collapse
|
26
|
Feldman D, Kowbel DJ, Glass NL, Yarden O, Hadar Y. A role for small secreted proteins (SSPs) in a saprophytic fungal lifestyle: Ligninolytic enzyme regulation in Pleurotus ostreatus. Sci Rep 2017; 7:14553. [PMID: 29109463 PMCID: PMC5674062 DOI: 10.1038/s41598-017-15112-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 10/20/2017] [Indexed: 12/12/2022] Open
Abstract
Small secreted proteins (SSPs), along with lignocellulose degrading enzymes, are integral components of the secretome of Pleurotus ostreatus, a white rot fungus. In this study, we identified 3 genes (ssp1, 2 and 3) encoding proteins that are annotated as SSPs and that exhibited of ~4,500- fold expression, 24 hr following exposure to the toxic compound 5-hydroxymethylfurfural (HMF). Homologues to genes encoding these SSPs are present in the genomes of other basidiomycete fungi, however the role of SSPs is not yet understood. SSPs, aryl-alcohol oxidases (AAO) and the intracellular aryl-alcohol dehydrogenases (AAD) were also produced after exposure to other aryl-alcohols, known substrates and inducers of AAOs, and during idiophase (after the onset of secondary metabolism). A knockdown strain of ssp1 exhibited reduced production of AAO-and AAD-encoding genes after HMF exposure. Conversely, a strain overexpressing ssp1 exhibited elevated expression of genes encoding AAOs and ADD, resulting in a 3-fold increase in enzymatic activity of AAOs, as well as increased expression and protein abundance of versatile peroxidase 1, which directly degrades lignin. We propose that in addition to symbionts and pathogens, SSPs also have roles in saprophytes and function in P. ostreatus as components of the ligninolytic system.
Collapse
Affiliation(s)
- Daria Feldman
- The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, Department of Plant Pathology and Microbiology, Rehovot, 76100, Israel
| | - David J Kowbel
- University of California at Berkeley UC Berkeley, Department of Plant and Microbial Biology, 111 Koshland Hall, Berkeley, California, 94720, USA
| | - N Louise Glass
- University of California at Berkeley UC Berkeley, Department of Plant and Microbial Biology, 111 Koshland Hall, Berkeley, California, 94720, USA
| | - Oded Yarden
- The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, Department of Plant Pathology and Microbiology, Rehovot, 76100, Israel
| | - Yitzhak Hadar
- The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, Department of Plant Pathology and Microbiology, Rehovot, 76100, Israel.
| |
Collapse
|
27
|
Huberman LB, Coradetti ST, Glass NL. Network of nutrient-sensing pathways and a conserved kinase cascade integrate osmolarity and carbon sensing in Neurospora crassa. Proc Natl Acad Sci U S A 2017; 114:E8665-E8674. [PMID: 28973881 PMCID: PMC5642704 DOI: 10.1073/pnas.1707713114] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Identifying nutrients available in the environment and utilizing them in the most efficient manner is a challenge common to all organisms. The model filamentous fungus Neurospora crassa is capable of utilizing a variety of carbohydrates, from simple sugars to the complex carbohydrates found in plant cell walls. The zinc binuclear cluster transcription factor CLR-1 is necessary for utilization of cellulose, a major, recalcitrant component of the plant cell wall; however, expression of clr-1 in the absence of an inducer is not sufficient to induce cellulase gene expression. We performed a screen for unidentified actors in the cellulose-response pathway and identified a gene encoding a hypothetical protein (clr-3) that is required for repression of CLR-1 activity in the absence of an inducer. Using clr-3 mutants, we implicated the hyperosmotic-response pathway in the tunable regulation of glycosyl hydrolase production in response to changes in osmolarity. The role of the hyperosmotic-response pathway in nutrient sensing may indicate that cells use osmolarity as a proxy for the presence of free sugar in their environment. These signaling pathways form a nutrient-sensing network that allows Ncrassa cells to tightly regulate gene expression in response to environmental conditions.
Collapse
Affiliation(s)
- Lori B Huberman
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720
- Energy Biosciences Institute, University of California, Berkeley, CA 94720
| | - Samuel T Coradetti
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720
- Energy Biosciences Institute, University of California, Berkeley, CA 94720
| | - N Louise Glass
- Plant and Microbial Biology Department, University of California, Berkeley, CA 94720;
- Energy Biosciences Institute, University of California, Berkeley, CA 94720
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| |
Collapse
|
28
|
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.
Collapse
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
| |
Collapse
|
29
|
Jacobson DJ, Powell AJ, Dettman JR, Saenz GS, Barton MM, Hiltz MD, Dvorachek WH, Glass NL, Taylor JW, Natvig DO. Neurosporain temperate forests of western North America. Mycologia 2017. [DOI: 10.1080/15572536.2005.11832998] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- David J. Jacobson
- Department of Biological Sciences, Stanford University, Stanford, California 94305-5020, and Department of Plant and Microbial Biology, University of California, Berkeley, California 94720-3102
| | - Amy J. Powell
- Department of Biology, University of New Mexico, Albuquerque, New Mexico 87131
| | - Jeremy R. Dettman
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720-3102
| | - Gregory S. Saenz
- Department of Biology, University of New Mexico, Albuquerque, New Mexico 87131
| | | | - Megan D. Hiltz
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720-3102
| | | | | | - John W. Taylor
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720-3102
| | - Donald O. Natvig
- Department of Biology, University of New Mexico, Albuquerque, New Mexico 87131
| |
Collapse
|
30
|
Thieme N, Wu VW, Dietschmann A, Salamov AA, Wang M, Johnson J, Singan VR, Grigoriev IV, Glass NL, Somerville CR, Benz JP. The transcription factor PDR-1 is a multi-functional regulator and key component of pectin deconstruction and catabolism in Neurospora crassa. Biotechnol Biofuels 2017; 10:149. [PMID: 28616073 PMCID: PMC5469009 DOI: 10.1186/s13068-017-0807-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 04/29/2017] [Indexed: 05/09/2023]
Abstract
BACKGROUND Pectin is an abundant component in many fruit and vegetable wastes and could therefore be an excellent resource for biorefinery, but is currently underutilized. Fungal pectinases already play a crucial role for industrial purposes, such as for foodstuff processing. However, the regulation of pectinase gene expression is still poorly understood. For an optimal utilization of plant biomass for biorefinery and biofuel production, a detailed analysis of the underlying regulatory mechanisms is warranted. In this study, we applied the genetic resources of the filamentous ascomycete species Neurospora crassa to screen for transcription factors that play a major role in pectinase induction. RESULTS The pectin degradation regulator-1 (PDR-1) was identified through a transcription factor mutant screen in N. crassa. The Δpdr-1 mutant exhibited a severe growth defect on pectin and all tested pectin-related poly- and monosaccharides. Biochemical as well as transcriptional analyses of WT and the Δpdr-1 mutant revealed that while PDR-1-mediated gene induction was dependent on the presence of l-rhamnose, it also strongly affected the degradation of the homogalacturonan backbone. The expression of the endo-polygalacturonase gh28-1 was greatly reduced in the Δpdr-1 mutant, while the expression levels of all pectate lyase genes increased. Moreover, a pdr-1 overexpression strain displayed substantially increased pectinase production. Promoter analysis of the PDR-1 regulon allowed refinement of the putative PDR-1 DNA-binding motif. CONCLUSIONS PDR-1 is highly conserved in filamentous ascomycete fungi and is present in many pathogenic and industrially important fungi. Our data demonstrate that the function of PDR-1 in N. crassa combines features of two recently described transcription factors in Aspergillus niger (RhaR) and Botrytis cinerea (GaaR). The results presented in this study contribute to a broader understanding of how pectin degradation is orchestrated in filamentous fungi and how it could be manipulated for optimized pectinase production.
Collapse
Affiliation(s)
- Nils Thieme
- HFM, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Vincent W. Wu
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA USA
- Energy Biosciences Institute, University of California, Berkeley, Berkeley, CA USA
| | - Axel Dietschmann
- HFM, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
- Department of Infection Biology, Institute for Clinical Microbiology, Immunology and Hygiene, Universitätsklinikum Erlangen and Friedrich-Alexander Universität, Erlangen-Nuremberg, Germany
| | - Asaf A. Salamov
- US Department of Energy Joint Genome Institute (JGI), Walnut Creek, CA USA
| | - Mei Wang
- US Department of Energy Joint Genome Institute (JGI), Walnut Creek, CA USA
| | - Jenifer Johnson
- US Department of Energy Joint Genome Institute (JGI), Walnut Creek, CA USA
| | - Vasanth R. Singan
- US Department of Energy Joint Genome Institute (JGI), Walnut Creek, CA USA
| | - Igor V. Grigoriev
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA USA
- US Department of Energy Joint Genome Institute (JGI), Walnut Creek, CA USA
| | - N. Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA USA
- Energy Biosciences Institute, University of California, Berkeley, Berkeley, CA USA
- Environmental Genomics and System Biology, Lawrence Berkeley National Laboratory, Berkeley, CA USA
| | - Chris R. Somerville
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA USA
- Energy Biosciences Institute, University of California, Berkeley, Berkeley, CA USA
| | - J. Philipp Benz
- HFM, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| |
Collapse
|
31
|
Samal A, Craig JP, Coradetti ST, Benz JP, Eddy JA, Price ND, Glass NL. Network reconstruction and systems analysis of plant cell wall deconstruction by Neurospora crassa. Biotechnol Biofuels 2017; 10:225. [PMID: 28947916 PMCID: PMC5609067 DOI: 10.1186/s13068-017-0901-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/05/2017] [Indexed: 05/21/2023]
Abstract
BACKGROUND Plant biomass degradation by fungal-derived enzymes is rapidly expanding in economic importance as a clean and efficient source for biofuels. The ability to rationally engineer filamentous fungi would facilitate biotechnological applications for degradation of plant cell wall polysaccharides. However, incomplete knowledge of biomolecular networks responsible for plant cell wall deconstruction impedes experimental efforts in this direction. RESULTS To expand this knowledge base, a detailed network of reactions important for deconstruction of plant cell wall polysaccharides into simple sugars was constructed for the filamentous fungus Neurospora crassa. To reconstruct this network, information was integrated from five heterogeneous data types: functional genomics, transcriptomics, proteomics, genetics, and biochemical characterizations. The combined information was encapsulated into a feature matrix and the evidence weighted to assign annotation confidence scores for each gene within the network. Comparative analyses of RNA-seq and ChIP-seq data shed light on the regulation of the plant cell wall degradation network, leading to a novel hypothesis for degradation of the hemicellulose mannan. The transcription factor CLR-2 was subsequently experimentally shown to play a key role in the mannan degradation pathway of N. crassa. CONCLUSIONS Here we built a network that serves as a scaffold for integration of diverse experimental datasets. This approach led to the elucidation of regulatory design principles for plant cell wall deconstruction by filamentous fungi and a novel function for the transcription factor CLR-2. This expanding network will aid in efforts to rationally engineer industrially relevant hyper-production strains.
Collapse
Affiliation(s)
- Areejit Samal
- Institute for Systems Biology, Seattle, WA 98109 USA
- Energy Biosciences Institute, University of California Berkeley, Berkeley, CA 94704 USA
- The Institute of Mathematical Sciences, Homi Bhabha National Institute, Chennai, 600113 India
- The Abdus Salam International Centre for Theoretical Physics, 34151 Trieste, Italy
| | - James P. Craig
- Energy Biosciences Institute, University of California Berkeley, Berkeley, CA 94704 USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
| | - Samuel T. Coradetti
- Energy Biosciences Institute, University of California Berkeley, Berkeley, CA 94704 USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
| | - J. Philipp Benz
- Energy Biosciences Institute, University of California Berkeley, Berkeley, CA 94704 USA
- Holzforschung München, TUM School of Life Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany
| | - James A. Eddy
- Institute for Systems Biology, Seattle, WA 98109 USA
| | | | - N. Louise Glass
- Energy Biosciences Institute, University of California Berkeley, Berkeley, CA 94704 USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
| |
Collapse
|
32
|
Abstract
The herbivore gut is a fascinating ecosystem exquisitely adapted to plant biomass degradation. Within this ecosystem, anaerobic fungi invade biomass and secrete hydrolytic enzymes. In a recent study, Solomon et al. characterized three anaerobic fungi by transcriptomics, proteomics, and functional analyses to identify novel components essential for plant biomass deconstruction.
Collapse
Affiliation(s)
- N Louise Glass
- Plant and Microbial Biology Department, Energy Biosciences Institute, The University of California, Berkeley, CA 94720-3102, USA.
| |
Collapse
|
33
|
Heller J, Zhao J, Rosenfield G, Kowbel DJ, Gladieux P, Glass NL. Characterization of Greenbeard Genes Involved in Long-Distance Kind Discrimination in a Microbial Eukaryote. PLoS Biol 2016; 14:e1002431. [PMID: 27077707 PMCID: PMC4831770 DOI: 10.1371/journal.pbio.1002431] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 03/11/2016] [Indexed: 01/09/2023] Open
Abstract
Microorganisms are capable of communication and cooperation to perform social activities. Cooperation can be enforced using kind discrimination mechanisms in which individuals preferentially help or punish others, depending on genetic relatedness only at certain loci. In the filamentous fungus Neurospora crassa, genetically identical asexual spores (germlings) communicate and fuse in a highly regulated process, which is associated with fitness benefits during colony establishment. Recognition and chemotropic interactions between isogenic germlings requires oscillation of the mitogen-activated protein kinase (MAPK) signal transduction protein complex (NRC-1, MEK-2, MAK-2, and the scaffold protein HAM-5) to specialized cell fusion structures termed conidial anastomosis tubes. Using a population of 110 wild N. crassa isolates, we investigated germling fusion between genetically unrelated individuals and discovered that chemotropic interactions are regulated by kind discrimination. Distinct communication groups were identified, in which germlings within one communication group interacted at high frequency, while germlings from different communication groups avoided each other. Bulk segregant analysis followed by whole genome resequencing identified three linked genes (doc-1, doc-2, and doc-3), which were associated with communication group phenotype. Alleles at doc-1, doc-2, and doc-3 fell into five haplotypes that showed transspecies polymorphism. Swapping doc-1 and doc-2 alleles from different communication group strains was necessary and sufficient to confer communication group affiliation. During chemotropic interactions, DOC-1 oscillated with MAK-2 to the tips of conidial anastomosis tubes, while DOC-2 was statically localized to the plasma membrane. Our data indicate that doc-1, doc-2, and doc-3 function as "greenbeard" genes, involved in mediating long-distance kind recognition that involves actively searching for one's own type, resulting in cooperation between non-genealogical relatives. Our findings serve as a basis for investigations into the mechanisms associated with attraction, fusion, and kind recognition in other eukaryotic species.
Collapse
Affiliation(s)
- Jens Heller
- The Plant and Microbial Biology Department, The University of California, Berkeley, California, United States of America
| | - Jiuhai Zhao
- The Plant and Microbial Biology Department, The University of California, Berkeley, California, United States of America
| | - Gabriel Rosenfield
- The Plant and Microbial Biology Department, The University of California, Berkeley, California, United States of America
| | - David J. Kowbel
- The Plant and Microbial Biology Department, The University of California, Berkeley, California, United States of America
| | | | - N. Louise Glass
- The Plant and Microbial Biology Department, The University of California, Berkeley, California, United States of America
- * E-mail:
| |
Collapse
|
34
|
Lopez-Moya F, Kowbel D, Nueda MJ, Palma-Guerrero J, Glass NL, Lopez-Llorca LV. Neurospora crassa transcriptomics reveals oxidative stress and plasma membrane homeostasis biology genes as key targets in response to chitosan. Mol Biosyst 2016; 12:391-403. [PMID: 26694141 PMCID: PMC4729629 DOI: 10.1039/c5mb00649j] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chitosan is a natural polymer with antimicrobial activity. Chitosan causes plasma membrane permeabilization and induction of intracellular reactive oxygen species (ROS) in Neurospora crassa. We have determined the transcriptional profile of N. crassa to chitosan and identified the main gene targets involved in the cellular response to this compound. Global network analyses showed membrane, transport and oxidoreductase activity as key nodes affected by chitosan. Activation of oxidative metabolism indicates the importance of ROS and cell energy together with plasma membrane homeostasis in N. crassa response to chitosan. Deletion strain analysis of chitosan susceptibility pointed NCU03639 encoding a class 3 lipase, involved in plasma membrane repair by lipid replacement, and NCU04537 a MFS monosaccharide transporter related to assimilation of simple sugars, as main gene targets of chitosan. NCU10521, a glutathione S-transferase-4 involved in the generation of reducing power for scavenging intracellular ROS is also a determinant chitosan gene target. Ca(2+) increased tolerance to chitosan in N. crassa. Growth of NCU10610 (fig 1 domain) and SYT1 (a synaptotagmin) deletion strains was significantly increased by Ca(2+) in the presence of chitosan. Both genes play a determinant role in N. crassa membrane homeostasis. Our results are of paramount importance for developing chitosan as an antifungal.
Collapse
Affiliation(s)
- Federico Lopez-Moya
- Laboratory of Plant Pathology, Multidisciplinary Institute for Environmental Studies (MIES) Ramon Margalef, Department of Marine Sciences and Applied Biology, University of Alicante, E-03080 Alicante, Spain.
| | - David Kowbel
- Department of Plant and Microbial Biology, University of California, Berkeley CA, 94720-3120 USA.
| | - Maria José Nueda
- Statistics and Operation Research Department, University of Alicante, E-03080 Alicante, Spain.
| | - Javier Palma-Guerrero
- Department of Plant and Microbial Biology, University of California, Berkeley CA, 94720-3120 USA.
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley CA, 94720-3120 USA.
| | - Luis Vicente Lopez-Llorca
- Laboratory of Plant Pathology, Multidisciplinary Institute for Environmental Studies (MIES) Ramon Margalef, Department of Marine Sciences and Applied Biology, University of Alicante, E-03080 Alicante, Spain.
| |
Collapse
|
35
|
Zhao J, Gladieux P, Hutchison E, Bueche J, Hall C, Perraudeau F, Glass NL. Identification of Allorecognition Loci in Neurospora crassa by Genomics and Evolutionary Approaches. Mol Biol Evol 2015; 32:2417-32. [PMID: 26025978 PMCID: PMC4540973 DOI: 10.1093/molbev/msv125] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Understanding the genetic and molecular bases of the ability to distinguish self from nonself (allorecognition) and mechanisms underlying evolution of allorecognition systems is an important endeavor for understanding cases where it becomes dysfunctional, such as in autoimmune disorders. In filamentous fungi, allorecognition can result in vegetative or heterokaryon incompatibility, which is a type of programmed cell death that occurs following fusion of genetically different cells. Allorecognition is genetically controlled by het loci, with coexpression of any combination of incompatible alleles triggering vegetative incompatibility. Herein, we identified, characterized, and inferred the evolutionary history of candidate het loci in the filamentous fungus Neurospora crassa. As characterized het loci encode proteins carrying an HET domain, we annotated HET domain genes in 25 isolates from a natural population along with the N. crassa reference genome using resequencing data. Because allorecognition systems can be affected by frequency-dependent selection favoring rare alleles (i.e., balancing selection), we mined resequencing data for HET domain loci whose alleles displayed elevated levels of variability, excess of intermediate frequency alleles, and deep gene genealogies. From these analyses, 34 HET domain loci were identified as likely to be under balancing selection. Using transformation, incompatibility assays and genetic analyses, we determined that one of these candidates functioned as a het locus (het-e). The het-e locus has three divergent allelic groups that showed signatures of positive selection, intra- and intergroup recombination, and trans-species polymorphism. Our findings represent a compelling case of balancing selection functioning on multiple alleles across multiple loci potentially involved in allorecognition.
Collapse
Affiliation(s)
- Jiuhai Zhao
- Plant and Microbial Biology Department, University of California, Berkeley
| | - Pierre Gladieux
- Plant and Microbial Biology Department, University of California, Berkeley INRA, UMR BGPI, TA A54/K, Montpellier, France; CIRAD, Montpellier, France
| | - Elizabeth Hutchison
- Plant and Microbial Biology Department, University of California, Berkeley Biology Department, 1 College Circle SUNY Geneseo, Geneseo, NY
| | - Joanna Bueche
- Plant and Microbial Biology Department, University of California, Berkeley
| | - Charles Hall
- Plant and Microbial Biology Department, University of California, Berkeley
| | - Fanny Perraudeau
- Plant and Microbial Biology Department, University of California, Berkeley Ecole Polytechnique, Palaiseau, France
| | - N Louise Glass
- Plant and Microbial Biology Department, University of California, Berkeley
| |
Collapse
|
36
|
Feldman D, Kowbel DJ, Glass NL, Yarden O, Hadar Y. Detoxification of 5-hydroxymethylfurfural by the Pleurotus ostreatus lignolytic enzymes aryl alcohol oxidase and dehydrogenase. Biotechnol Biofuels 2015; 8:63. [PMID: 25897324 PMCID: PMC4403834 DOI: 10.1186/s13068-015-0244-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 03/24/2015] [Indexed: 05/09/2023]
Abstract
BACKGROUND Current large-scale pretreatment processes for lignocellulosic biomass are generally accompanied by the formation of toxic degradation products, such as 5-hydroxymethylfurfural (HMF), which inhibit cellulolytic enzymes and fermentation by ethanol-producing yeast. Overcoming these toxic effects is a key technical barrier in the biochemical conversion of plant biomass to biofuels. Pleurotus ostreatus, a white-rot fungus, can efficiently degrade lignocellulose. In this study, we analyzed the ability of P. ostreatus to tolerate and metabolize HMF and investigated relevant molecular pathways associated with these processes. RESULTS P. ostreatus was capable to metabolize and detoxify HMF 30 mM within 48 h, converting it into 2,5-bis-hydroxymethylfuran (HMF alcohol) and 2,5-furandicarboxylic acid (FDCA), which subsequently allowed the normal yeast growth in amended media. We show that two enzymes groups, which belong to the ligninolytic system, aryl-alcohol oxidases and a dehydrogenase, are involved in this process. HMF induced the transcription and production of these enzymes and was accompanied by an increase in activity levels. We also demonstrate that following the induction of these enzymes, HMF could be metabolized in vitro. CONCLUSIONS Aryl-alcohol oxidase and dehydrogenase gene family members are part of the transcriptional and subsequent translational response to HMF exposure in P. ostreatus and are involved in HMF transformation. Based on our data, we propose that these enzymatic capacities of P. ostreatus either be integrated in biomass pretreatment or the genes encoding these enzymes may function to detoxify HMF via heterologous expression in fermentation organisms, such as Saccharomyces cerevisiae.
Collapse
Affiliation(s)
- Daria Feldman
- />Department of Plant Pathology and Microbiology, The R.H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, POB 12, Rehovot, 76100 Israel
| | - David J Kowbel
- />Department of Plant and Microbial Biology, University of California at Berkeley, 111 Koshland Hall, Berkeley, California 94720 USA
| | - N Louise Glass
- />Department of Plant and Microbial Biology, University of California at Berkeley, 111 Koshland Hall, Berkeley, California 94720 USA
| | - Oded Yarden
- />Department of Plant Pathology and Microbiology, The R.H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, POB 12, Rehovot, 76100 Israel
| | - Yitzhak Hadar
- />Department of Plant Pathology and Microbiology, The R.H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, POB 12, Rehovot, 76100 Israel
| |
Collapse
|
37
|
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. Genom 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] [What about the content of this article? (0)] [Affiliation(s)] [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.
Collapse
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
| |
Collapse
|
38
|
Li X, Yu VY, Lin Y, Chomvong K, Estrela R, Park A, Liang JM, Znameroski EA, Feehan J, Kim SR, Jin YS, Glass NL, Cate JHD. Expanding xylose metabolism in yeast for plant cell wall conversion to biofuels. eLife 2015; 4. [PMID: 25647728 PMCID: PMC4338637 DOI: 10.7554/elife.05896] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 02/02/2015] [Indexed: 12/18/2022] Open
Abstract
Sustainable biofuel production from renewable biomass will require the efficient and complete use of all abundant sugars in the plant cell wall. Using the cellulolytic fungus Neurospora crassa as a model, we identified a xylodextrin transport and consumption pathway required for its growth on hemicellulose. Reconstitution of this xylodextrin utilization pathway in Saccharomyces cerevisiae revealed that fungal xylose reductases act as xylodextrin reductases, producing xylosyl-xylitol oligomers as metabolic intermediates. These xylosyl-xylitol intermediates are generated by diverse fungi and bacteria, indicating that xylodextrin reduction is widespread in nature. Xylodextrins and xylosyl-xylitol oligomers are then hydrolyzed by two hydrolases to generate intracellular xylose and xylitol. Xylodextrin consumption using a xylodextrin transporter, xylodextrin reductases and tandem intracellular hydrolases in cofermentations with sucrose and glucose greatly expands the capacity of yeast to use plant cell wall-derived sugars and has the potential to increase the efficiency of both first-generation and next-generation biofuel production. DOI:http://dx.doi.org/10.7554/eLife.05896.001 Plants can be used to make ‘biofuels’, which are more sustainable alternatives to traditional fuels made from petroleum. Unfortunately, most biofuels are currently made from simple sugars or starch extracted from parts of plants that we also use for food, such as the grains of cereal crops. Making biofuels from the parts of the plant that are not used for food—for example, the stems or leaves—would enable us to avoid a trade-off between food and fuel production. However, most of the sugars in these parts of the plant are locked away in the form of large, complex carbohydrates called cellulose and hemicellulose, which form the rigid cell wall surrounding each plant cell. Currently, the industrial processes that can be used to make biofuels from plant cell walls are expensive and use a lot of energy. They involve heating or chemically treating the plant material to release the cellulose and hemicellulose. Then, large quantities of enzymes are added to break these carbohydrates down into simple sugars that can then be converted into alcohol (a biofuel) by yeast. Fungi may be able to provide us with a better solution. Many species are able to grow on plants because they can break down cellulose and hemicellulose into simple sugars they can use for energy. If the genes involved in this process could be identified and inserted into yeast it may provide a new, cheaper method to make biofuels from plant cell walls. To address this challenge, Li et al. studied how the fungus Neurospora crassa breaks down hemicellulose. This study identified a protein that can transport molecules of xylodextrin—which is found in hemicellulose—into the cells of the fungus, and two enzymes that break down the xylodextrin to make simple sugars, using a previously unknown chemical intermediate. When Li et al. inserted the genes that make the transport protein and the enzymes into yeast, the yeast were able to use plant cell wall material to make simple sugars and convert these to alcohol. The yeast used more of the xylodextrin when they were grown with an additional source of energy, such as the sugars glucose or sucrose. Li et al.'s findings suggest that giving yeast the ability to break down hemicellulose has the potential to improve the efficiency of biofuel production. The next challenge will be to improve the process so that the yeast can convert the xylodextrin and simple sugars more rapidly. DOI:http://dx.doi.org/10.7554/eLife.05896.002
Collapse
Affiliation(s)
- Xin Li
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Vivian Yaci Yu
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Yuping Lin
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Kulika Chomvong
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, United States
| | - Raíssa Estrela
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Annsea Park
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Julie M Liang
- Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - Elizabeth A Znameroski
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Joanna Feehan
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Soo Rin Kim
- Institute for Genomic Biology, University of Illinois, Urbana, United States
| | - Yong-Su Jin
- Institute for Genomic Biology, University of Illinois, Urbana, United States
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, United States
| | - Jamie H D Cate
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| |
Collapse
|
39
|
Reilly MC, Qin L, Craig JP, Starr TL, Glass NL. Deletion of homologs of the SREBP pathway results in hyper-production of cellulases in Neurospora crassa and Trichoderma reesei. Biotechnol Biofuels 2015; 8:121. [PMID: 26288653 PMCID: PMC4539670 DOI: 10.1186/s13068-015-0297-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 07/24/2015] [Indexed: 05/05/2023]
Abstract
BACKGROUND The filamentous fungus Neurospora crassa efficiently utilizes plant biomass and is a model organism for genetic, molecular and cellular biology studies. Here, a set of 567 single-gene deletion strains was assessed for cellulolytic activity as compared to the wild-type parental strain. Mutant strains included were those carrying a deletion in: (1) genes encoding proteins homologous to those implicated in the Saccharomyces cerevisiae secretion apparatus; (2) genes that are homologous to those known to differ between the Trichoderma reesei hyper-secreting strain RUT-C30 and its ancestral wild-type strain; (3) genes encoding proteins identified in the secretome of N. crassa when cultured on plant biomass and (4) genes encoding proteins predicted to traverse the secretory pathway. RESULTS The 567 single-gene deletion collection was cultured on crystalline cellulose and a comparison of levels of secreted protein and cellulase activity relative to the wild-type strain resulted in the identification of seven hyper-production and 18 hypo-production strains. Some of these deleted genes encoded proteins that are likely to act in transcription, protein synthesis and intracellular trafficking, but many encoded fungal-specific proteins of undetermined function. Characterization of several mutants peripherally linked to protein processing or secretion showed that the hyper- or hypo-production phenotypes were primarily a response to cellulose. The altered secretome of these strains was not limited to the production of cellulolytic enzymes, yet was part of the cellulosic response driven by the cellulase transcription factor CLR-2. Mutants implicated the loss of the SREBP pathway, which has been found to regulate ergosterol biosynthesis genes in response to hypoxic conditions, resulted in a hyper-production phenotype. Deletion of two SREBP pathway components in T. reesei also conferred a hyper-production phenotype under cellulolytic conditions. CONCLUSIONS These studies demonstrate the utility of screening the publicly available N. crassa single-gene deletion strain collection for a particular phenotype. Mutants in a predicted E3 ligase and its target SREBP transcription factor played an unanticipated role in protein production under cellulolytic conditions. Furthermore, phenotypes similar to those observed in N. crassa were seen following the targeted deletion of orthologous SREBP pathway loci in T. reesei, a fungal species commonly used in industrial enzyme production.
Collapse
Affiliation(s)
- Morgann C Reilly
- />Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
- />The Energy Biosciences Institute, University of California, Berkeley, CA 94720 USA
| | - Lina Qin
- />Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
- />The Energy Biosciences Institute, University of California, Berkeley, CA 94720 USA
| | - James P Craig
- />Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
- />The Energy Biosciences Institute, University of California, Berkeley, CA 94720 USA
| | - Trevor L Starr
- />Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
- />The Energy Biosciences Institute, University of California, Berkeley, CA 94720 USA
| | - N Louise Glass
- />Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
- />The Energy Biosciences Institute, University of California, Berkeley, CA 94720 USA
| |
Collapse
|
40
|
Abstract
Investigation of the red bread mold that contaminated French bakeries nearly two centuries ago has led to a wealth of discoveries that have impacted our understanding of genetic, biochemical, and molecular mechanisms in microbes, from Mendelian genetics and the gene-enzyme relationship to circadian rhythm and plant cell wall degradation. Early Neurospora research focused on elucidating mechanisms of genetic recombination and gene action and later progressed to addressing complex biological questions of eukaryotic microbes. Here we review the evolution of the filamentous fungus Neurospora as a model microbe over the past century. We discuss the origins of Neurospora as a model microbe, the immediate scientific impacts from work in this filamentous fungus, and how the introduction of other model organisms (i.e., Escherichia coli and Saccharomyces cerevisiae) redirected the focus of Neurospora research. Neurospora has and continues to inform our understanding of a myriad of basic scientific concepts and now has the opportunity to forge into the applied biosciences and biotechnology.
Collapse
Affiliation(s)
- Christine M Roche
- Chemical and Biomolecular Engineering Department, University of California, Berkeley, California USA Energy Biosciences Institute, University of California, Berkeley, California USA
| | - Jennifer J Loros
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire USA Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire USA
| | - Kevin McCluskey
- Fungal Genetics Stock Center, Department of Plant Pathology, Kansas State University, Manhattan, Kansas USA
| | - N Louise Glass
- Energy Biosciences Institute, University of California, Berkeley, California USA Plant and Microbial Biology Department, University of California, Berkeley, California USA
| |
Collapse
|
41
|
Xue Z, Ye Q, Anson SR, Yang J, Xiao G, Kowbel D, Glass NL, Crosthwaite SK, Liu Y. Transcriptional interference by antisense RNA is required for circadian clock function. Nature 2014; 514:650-3. [PMID: 25132551 PMCID: PMC4214883 DOI: 10.1038/nature13671] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 07/10/2014] [Indexed: 01/24/2023]
Abstract
Eukaryotic circadian oscillators consist of negative feedback loops that generate endogenous rhythmicities1. Natural antisense RNAs are found in a wide range of eukaryotic organisms2-5. Nevertheless, the physiological importance and mode of action of most antisense RNAs is not clear6-9. frequency (frq) encodes a component of the Neurospora core circadian negative feedback loop which was thought to generate sustained rhythmicity10. Transcription of qrf, the long non-coding frq antisense RNA, is light induced, and its level oscillates in antiphase to frq sense RNA3. Here we show that qrf transcription is regulated by both light-dependent and -independent mechanisms. Light-dependent qrf transcription represses frq expression and regulates clock resetting. qrf expression in the dark, on the other hand, is required for circadian rhythmicity. frq transcription also inhibits qrf expression and surprisingly, drives the antiphasic rhythm of qrf transcripts. The mutual inhibition of frq and qrf transcription thus forms a double negative feedback loop that is interlocked with the core feedback loop. Genetic and mathematical modeling analyses indicate that such an arrangement is required for robust and sustained circadian rhythmicity. Moreover, our results suggest that antisense transcription inhibits sense expression by mediating chromatin modifications and premature transcription termination. Together, our results established antisense transcription as an essential feature in a circadian system and shed light on the importance and mechanism of antisense action.
Collapse
Affiliation(s)
- Zhihong Xue
- Department of Physiology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Qiaohong Ye
- Department of Physiology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Simon R Anson
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
| | - Jichen Yang
- Department of Clinical Sciences, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Guanghua Xiao
- Department of Clinical Sciences, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - David Kowbel
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA
| | | | - Yi Liu
- Department of Physiology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| |
Collapse
|
42
|
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. Microb 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] [What about the content of this article? (0)] [Affiliation(s)] [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.
Collapse
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
| |
Collapse
|
43
|
Xiong Y, Sun J, Glass NL. VIB1, a link between glucose signaling and carbon catabolite repression, is essential for plant cell wall degradation by Neurospora crassa. PLoS Genet 2014; 10:e1004500. [PMID: 25144221 PMCID: PMC4140635 DOI: 10.1371/journal.pgen.1004500] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Accepted: 05/27/2014] [Indexed: 11/18/2022] Open
Abstract
Filamentous fungi that thrive on plant biomass are the major producers of hydrolytic enzymes used to decompose lignocellulose for biofuel production. Although induction of cellulases is regulated at the transcriptional level, how filamentous fungi sense and signal carbon-limited conditions to coordinate cell metabolism and regulate cellulolytic enzyme production is not well characterized. By screening a transcription factor deletion set in the filamentous fungus Neurospora crassa for mutants unable to grow on cellulosic materials, we identified a role for the transcription factor, VIB1, as essential for cellulose utilization. VIB1 does not directly regulate hydrolytic enzyme gene expression or function in cellulosic inducer signaling/processing, but affects the expression level of an essential regulator of hydrolytic enzyme genes, CLR2. Transcriptional profiling of a Δvib-1 mutant suggests that it has an improper expression of genes functioning in metabolism and energy and a deregulation of carbon catabolite repression (CCR). By characterizing new genes, we demonstrate that the transcription factor, COL26, is critical for intracellular glucose sensing/metabolism and plays a role in CCR by negatively regulating cre-1 expression. Deletion of the major player in CCR, cre-1, or a deletion of col-26, did not rescue the growth of Δvib-1 on cellulose. However, the synergistic effect of the Δcre-1; Δcol-26 mutations circumvented the requirement of VIB1 for cellulase gene expression, enzyme secretion and cellulose deconstruction. Our findings support a function of VIB1 in repressing both glucose signaling and CCR under carbon-limited conditions, thus enabling a proper cellular response for plant biomass deconstruction and utilization.
Collapse
Affiliation(s)
- Yi Xiong
- Plant and Microbial Biology Department and The Energy Biosciences Institute, The University of California, Berkeley, Berkeley, California, United States of America
| | - Jianping Sun
- Plant and Microbial Biology Department and The Energy Biosciences Institute, The University of California, Berkeley, Berkeley, California, United States of America
| | - N. Louise Glass
- Plant and Microbial Biology Department and The Energy Biosciences Institute, The University of California, Berkeley, Berkeley, California, United States of America
| |
Collapse
|
44
|
Xiong Y, Coradetti ST, Li X, Gritsenko MA, Clauss T, Petyuk V, Camp D, Smith R, Cate JHD, Yang F, Glass NL. The proteome and phosphoproteome of Neurospora crassa in response to cellulose, sucrose and carbon starvation. Fungal Genet Biol 2014; 72:21-33. [PMID: 24881580 DOI: 10.1016/j.fgb.2014.05.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 05/16/2014] [Accepted: 05/17/2014] [Indexed: 12/15/2022]
Abstract
Improving cellulolytic enzyme production by plant biomass degrading fungi holds great potential in reducing costs associated with production of next-generation biofuels generated from lignocellulose. How fungi sense cellulosic materials and respond by secreting enzymes has mainly been examined by assessing function of transcriptional regulators and via transcriptional profiling. Here, we obtained global proteomic and phosphoproteomic profiles of the plant biomass degrading filamentous fungus Neurospora crassa grown on different carbon sources, i.e. sucrose, no carbon, and cellulose, by performing isobaric tags for relative and absolute quantification (iTRAQ)-based LC-MS/MS analyses. A comparison between proteomes and transcriptomes under identical carbon conditions suggests that extensive post-transcriptional regulation occurs in N. crassa in response to exposure to cellulosic material. Several hundred amino acid residues with differential phosphorylation levels on crystalline cellulose (Avicel) or carbon-free medium vs sucrose medium were identified, including phosphorylation sites in a major transcriptional activator for cellulase genes, CLR1, as well as a cellobionic acid transporter, CBT1. Mutation of phosphorylation sites on CLR1 did not have a major effect on transactivation of cellulase production, while mutation of phosphorylation sites in CBT1 increased its transporting capacity. Our data provides rich information at both the protein and phosphorylation levels of the early cellular responses to carbon starvation and cellulosic induction and aids in a greater understanding of the underlying post-transcriptional regulatory mechanisms in filamentous fungi.
Collapse
Affiliation(s)
- Yi Xiong
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Samuel T Coradetti
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Xin Li
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA
| | | | - Therese Clauss
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - Vlad Petyuk
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - David Camp
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - Richard Smith
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - Jamie H D Cate
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA; Department of Chemistry, University of California, Berkeley, CA, USA
| | - Feng Yang
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.
| |
Collapse
|
45
|
Roche CM, Glass NL, Blanch HW, Clark DS. Engineering the filamentous fungusNeurospora crassafor lipid production from lignocellulosic biomass. Biotechnol Bioeng 2014; 111:1097-107. [DOI: 10.1002/bit.25211] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 02/03/2014] [Accepted: 02/06/2014] [Indexed: 01/14/2023]
Affiliation(s)
- Christine M. Roche
- The Chemical and Biomolecular Engineering Department; The University of California; Berkeley California 94720
- The Energy Biosciences Institute; The University of California; Berkeley California 94720
| | - N. Louise Glass
- The Energy Biosciences Institute; The University of California; Berkeley California 94720
- The Plant and Microbial Biology Department; The University of California; Berkeley California
| | - Harvey W. Blanch
- The Chemical and Biomolecular Engineering Department; The University of California; Berkeley California 94720
- The Energy Biosciences Institute; The University of California; Berkeley California 94720
| | - Douglas S. Clark
- The Chemical and Biomolecular Engineering Department; The University of California; Berkeley California 94720
- The Energy Biosciences Institute; The University of California; Berkeley California 94720
| |
Collapse
|
46
|
Palma-Guerrero J, Leeder AC, Welch J, Glass NL. Identification and characterization of LFD1, a novel protein involved in membrane merger during cell fusion in Neurospora crassa. Mol Microbiol 2014; 92:164-82. [PMID: 24673848 DOI: 10.1111/mmi.12545] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/04/2014] [Indexed: 11/30/2022]
Abstract
Despite its essential role in development, molecular mechanisms of membrane merger during cell-cell fusion in most eukaryotic organisms remain elusive. In the filamentous fungus Neurospora crassa, cell fusion occurs during asexual spore germination, where genetically identical germlings show chemotropic interactions and cell-cell fusion. Fusion of germlings and hyphae is required for the formation of the interconnected mycelial network characteristic of filamentous fungi. Previously, a multipass membrane protein, PRM1, was characterized and acts at the step of bilayer fusion in N. crassa. Here we describe the identification and characterization of lfd-1, encoding a single pass transmembrane protein, which is also involved in membrane merger. lfd-1 was identified by a targeted analysis of a transcriptional profile of a transcription factor mutant (Δpp-1) defective in germling fusion. The Δlfd-1 mutant shows a similar, but less severe, membrane merger defect as a ΔPrm1 mutant. By genetic analyses, we show that LFD1 and PRM1 act independently, but share a redundant function. The cell fusion frequency of both Δlfd-1 and ΔPrm1 mutants was sensitive to extracellular calcium concentration and was associated with an increase in cell lysis, which was suppressed by a calcium-dependent mechanism involving a homologue to synaptotagmin.
Collapse
|
47
|
Abstract
Approximately a tenth of all described fungal species can cause diseases in plants. A common feature of this process is the necessity to pass through the plant cell wall, an important barrier against pathogen attack. To this end, fungi possess a diverse array of secreted enzymes to depolymerize the main structural polysaccharide components of the plant cell wall, i.e., cellulose, hemicellulose, and pectin. Recent advances in genomic and systems-level studies have begun to unravel this diversity and have pinpointed cell wall-degrading enzyme (CWDE) families that are specifically present or enhanced in plant-pathogenic fungi. In this review, we discuss differences between the CWDE arsenal of plant-pathogenic and non-plant-pathogenic fungi, highlight the importance of individual enzyme families for pathogenesis, illustrate the secretory pathway that transports CWDEs out of the fungal cell, and report the transcriptional regulation of expression of CWDE genes in both saprophytic and phytopathogenic fungi.
Collapse
|
48
|
Znameroski EA, Li X, Tsai JC, Galazka JM, Glass NL, Cate JHD. Evidence for transceptor function of cellodextrin transporters in Neurospora crassa. J Biol Chem 2013; 289:2610-9. [PMID: 24344125 DOI: 10.1074/jbc.m113.533273] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Neurospora crassa colonizes burnt grasslands and metabolizes both cellulose and hemicellulose from plant cell walls. When switched from a favored carbon source to cellulose, N. crassa dramatically up-regulates expression and secretion of genes encoding lignocellulolytic enzymes. However, the means by which N. crassa and other filamentous fungi sense the presence of cellulose in the environment remains unclear. Previously, we have shown that a N. crassa mutant carrying deletions of three β-glucosidase enzymes (Δ3βG) lacks β-glucosidase activity, but efficiently induces cellulase gene expression and cellulolytic activity in the presence of cellobiose as the sole carbon source. These observations indicate that cellobiose, or a modified version of cellobiose, functions as an inducer of lignocellulolytic gene expression and activity in N. crassa. Here, we show that in N. crassa, two cellodextrin transporters, CDT-1 and CDT-2, contribute to cellulose sensing. A N. crassa mutant carrying deletions for both transporters is unable to induce cellulase gene expression in response to crystalline cellulose. Furthermore, a mutant lacking genes encoding both the β-glucosidase enzymes and cellodextrin transporters (Δ3βGΔ2T) does not induce cellulase gene expression in response to cellobiose. Point mutations that severely reduce cellobiose transport by either CDT-1 or CDT-2 when expressed individually do not greatly impact cellobiose induction of cellulase gene expression. These data suggest that the N. crassa cellodextrin transporters act as "transceptors" with dual functions - cellodextrin transport and receptor signaling that results in downstream activation of cellulolytic gene expression. Similar mechanisms of transceptor activity likely occur in related ascomycetes used for industrial cellulase production.
Collapse
|
49
|
Benz JP, Chau BH, Zheng D, Bauer S, Glass NL, Somerville CR. A comparative systems analysis of polysaccharide-elicited responses in Neurospora crassa reveals carbon source-specific cellular adaptations. Mol Microbiol 2013; 91:275-99. [PMID: 24224966 DOI: 10.1111/mmi.12459] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/11/2013] [Indexed: 12/31/2022]
Abstract
Filamentous fungi are powerful producers of hydrolytic enzymes for the deconstruction of plant cell wall polysaccharides. However, the central question of how these sugars are perceived in the context of the complex cell wall matrix remains largely elusive. To address this question in a systematic fashion we performed an extensive comparative systems analysis of how the model filamentous fungus Neurospora crassa responds to the three main cell wall polysaccharides: pectin, hemicellulose and cellulose. We found the pectic response to be largely independent of the cellulolytic one with some overlap to hemicellulose, and in its extent surprisingly high, suggesting advantages for the fungus beyond being a mere carbon source. Our approach furthermore allowed us to identify carbon source-specific adaptations, such as the induction of the unfolded protein response on cellulose, and a commonly induced set of 29 genes likely involved in carbon scouting. Moreover, by hierarchical clustering we generated a coexpression matrix useful for the discovery of new components involved in polysaccharide utilization. This is exemplified by the identification of lat-1, which we demonstrate to encode for the physiologically relevant arabinose transporter in Neurospora. The analyses presented here are an important step towards understanding fungal degradation processes of complex biomass.
Collapse
Affiliation(s)
- J Philipp Benz
- Energy Biosciences Institute, University of California Berkeley, Berkeley, California, USA
| | | | | | | | | | | |
Collapse
|
50
|
Affiliation(s)
| | - Monika Schmoll
- Austrian Institute of Technology GmbH (AIT), Health and Environment, Bioresources, 3430 Tulln, Austria
| | - Jamie H.D. Cate
- Molecular and Cellular Biology Department, and
- Chemistry Department, University of California, Berkeley, California 94720;
| | | |
Collapse
|