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Ornelas-Llamas MM, Pérez-Mozqueda LL, Callejas-Negrete OA, Castro-Longoria E. RHO-3 plays a significant role in hyphal extension rate, conidiation, and the integrity of the Spitzenkörper in Neurospora crassa. Fungal Genet Biol 2024; 171:103873. [PMID: 38266703 DOI: 10.1016/j.fgb.2024.103873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 01/19/2024] [Accepted: 01/20/2024] [Indexed: 01/26/2024]
Abstract
The Rho family of monomeric GTPases act as signaling proteins to establish and maintain cell polarity and other essential cellular processes. Rho3 is a GTPase of the Rho family that is exclusive of fungi that regulate cell polarity in yeast. However, studies have yet to explore its function in filamentous fungi. In this work, we investigated the role of RHO-3 in the model organism Neurospora crassa. Confocal microscopy analysis revealed that RHO-3 localizes in the outer region of the Spitzenkörper (Spk), in the plasma membrane from region II to the beginning of region III, and in the septa of mature hyphae. The phenotypic effect of the rho-3 deletion was analyzed. The results revealed that the rho-3 null strain showed severe defects in growth rate, aerial hyphae length, and conidia production. The organization of the Spk is also affected in the absence of RHO-3. Co-expression analysis of GFP-RHO-3 with glucan synthase 1 (GS-1-mChFP) and chitin synthase 1 (CHS-1-mChFP) revealed that RHO-3 localizes in the external region of the Spk in the macrovesicles zone. In summary, our results suggest that RHO-3 is not essential for the polarized growth of hyphae but plays a significant role in hyphal extension rate, conidiation, sexual reproduction and the integrity of the Spk, possibly regulating the delivery of macrovesicles to the apical dome.
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Affiliation(s)
- Martha M Ornelas-Llamas
- Department of Microbiology, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California, Mexico
| | - Luis L Pérez-Mozqueda
- Department of Microbiology, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California, Mexico; Center for Wine and Vine Studies (CEVIT), Technical and Higher Education Center (CETYS), Ensenada, Baja California, Mexico
| | - Olga A Callejas-Negrete
- Department of Microbiology, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California, Mexico
| | - Ernestina Castro-Longoria
- Department of Microbiology, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California, Mexico.
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2
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Chen Y, Liu J, Kang S, Wei D, Fan Y, Xiang M, Liu X. A palisade-shaped membrane reservoir is required for rapid ring cell inflation in Drechslerella dactyloides. Nat Commun 2023; 14:7376. [PMID: 37968349 PMCID: PMC10651832 DOI: 10.1038/s41467-023-43235-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 11/03/2023] [Indexed: 11/17/2023] Open
Abstract
Fusion of individual vesicles carrying membrane-building materials with the plasma membrane (PM) enables gradual cell expansion and shape change. Constricting ring (CR) cells of carnivorous fungi triple in size within 0.1-1 s to capture passing nematodes. Here, we investigated how a carnivorous fungus, Drechslerella dactyloides, executes rapid and irreversible PM expansion during CR inflation. During CR maturation, vesicles carrying membrane-building materials accumulate and fuse, forming a structure named the Palisade-shaped Membrane-building Structure (PMS) around the rumen side of ring cells. After CR inflation, the PMS disappears, with partially inflated cells displaying wavy PM and fully inflated cells exhibiting smooth PM, suggesting that the PMS serves as the reservoir for membrane-building materials to enable rapid and extensive PM expansion. The DdSnc1, a v-SNARE protein, accumulates at the inner side of ring cells and is necessary for PMS formation and CR inflation. This study elucidates the unique cellular mechanisms underpinning rapid CR inflation.
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Affiliation(s)
- Yue Chen
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, Frontiers Science Center for Cell Responses, College of Life Science, Nankai University, Tianjin, 300071, China
| | - Jia Liu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, Frontiers Science Center for Cell Responses, College of Life Science, Nankai University, Tianjin, 300071, China
| | - Seogchan Kang
- Department of Plant Pathology & Environmental Microbiology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Dongsheng Wei
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, Frontiers Science Center for Cell Responses, College of Life Science, Nankai University, Tianjin, 300071, China
| | - Yani Fan
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Meichun Xiang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Xingzhong Liu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, Frontiers Science Center for Cell Responses, College of Life Science, Nankai University, Tianjin, 300071, China.
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
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3
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Bauer I, Sarikaya Bayram Ö, Bayram Ö. The use of immunoaffinity purification approaches coupled with LC-MS/MS offers a powerful strategy to identify protein complexes in filamentous fungi. Essays Biochem 2023; 67:877-892. [PMID: 37681641 DOI: 10.1042/ebc20220253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/23/2023] [Accepted: 08/25/2023] [Indexed: 09/09/2023]
Abstract
Fungi are a diverse group of organisms that can be both beneficial and harmful to mankind. They have advantages such as producing food processing enzymes and antibiotics, but they can also be pathogens and produce mycotoxins that contaminate food. Over the past two decades, there have been significant advancements in methods for studying fungal molecular biology. These advancements have led to important discoveries in fungal development, physiology, pathogenicity, biotechnology, and natural product research. Protein complexes and protein-protein interactions (PPIs) play crucial roles in fungal biology. Various methods, including yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC), are used to investigate PPIs. However, affinity-based PPI methods like co-immunoprecipitation (Co-IP) are highly preferred because they represent the natural conditions of PPIs. In recent years, the integration of liquid chromatography coupled with mass spectrometry (LC-MS/MS) has been used to analyse Co-IPs, leading to the discovery of important protein complexes in filamentous fungi. In this review, we discuss the tandem affinity purification (TAP) method and single affinity purification methods such as GFP, HA, FLAG, and MYC tag purifications. These techniques are used to identify PPIs and protein complexes in filamentous fungi. Additionally, we compare the efficiency, time requirements, and material usage of Sepharose™ and magnetic-based purification systems. Overall, the advancements in fungal molecular biology techniques have provided valuable insights into the complex interactions and functions of proteins in fungi. The methods discussed in this review offer powerful tools for studying fungal biology and will contribute to further discoveries in this field.
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Affiliation(s)
- Ingo Bauer
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | | | - Özgür Bayram
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
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4
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Panstruga R, Antonin W, Lichius A. Looking outside the box: a comparative cross-kingdom view on the cell biology of the three major lineages of eukaryotic multicellular life. Cell Mol Life Sci 2023; 80:198. [PMID: 37418047 PMCID: PMC10329083 DOI: 10.1007/s00018-023-04843-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 06/16/2023] [Accepted: 06/17/2023] [Indexed: 07/08/2023]
Abstract
Many cell biological facts that can be found in dedicated scientific textbooks are based on findings originally made in humans and/or other mammals, including respective tissue culture systems. They are often presented as if they were universally valid, neglecting that many aspects differ-in part considerably-between the three major kingdoms of multicellular eukaryotic life, comprising animals, plants and fungi. Here, we provide a comparative cross-kingdom view on the basic cell biology across these lineages, highlighting in particular essential differences in cellular structures and processes between phyla. We focus on key dissimilarities in cellular organization, e.g. regarding cell size and shape, the composition of the extracellular matrix, the types of cell-cell junctions, the presence of specific membrane-bound organelles and the organization of the cytoskeleton. We further highlight essential disparities in important cellular processes such as signal transduction, intracellular transport, cell cycle regulation, apoptosis and cytokinesis. Our comprehensive cross-kingdom comparison emphasizes overlaps but also marked differences between the major lineages of the three kingdoms and, thus, adds to a more holistic view of multicellular eukaryotic cell biology.
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Affiliation(s)
- Ralph Panstruga
- Unit of Plant Molecular Cell Biology, Institute for Biology I, RWTH Aachen University, Worringerweg 1, 52056, Aachen, Germany.
| | - Wolfram Antonin
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, 52074, Aachen, Germany
| | - Alexander Lichius
- inncellys GmbH, Dorfstrasse 20/3, 6082, Patsch, Austria
- Department of Microbiology, University of Innsbruck, Technikerstrasse 25, 6020, Innsbruck, Austria
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Alder-Rangel A, Bailão AM, Herrera-Estrella A, Rangel AEA, Gácser A, Gasch AP, Campos CBL, Peters C, Camelim F, Verde F, Gadd GM, Braus G, Eisermann I, Quinn J, Latgé JP, Aguirre J, Bennett JW, Heitman J, Nosanchuk JD, Partida-Martínez LP, Bassilana M, Acheampong MA, Riquelme M, Feldbrügge M, Keller NP, Keyhani NO, Gunde-Cimerman N, Nascimento R, Arkowitz RA, Mouriño-Pérez RR, Naz SA, Avery SV, Basso TO, Terpitz U, Lin X, Rangel DEN. The IV International Symposium on Fungal Stress and the XIII International Fungal Biology Conference. Fungal Biol 2023; 127:1157-1179. [PMID: 37495306 DOI: 10.1016/j.funbio.2023.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 04/24/2023] [Indexed: 07/28/2023]
Abstract
For the first time, the International Symposium on Fungal Stress was joined by the XIII International Fungal Biology Conference. The International Symposium on Fungal Stress (ISFUS), always held in Brazil, is now in its fourth edition, as an event of recognized quality in the international community of mycological research. The event held in São José dos Campos, SP, Brazil, in September 2022, featured 33 renowned speakers from 12 countries, including: Austria, Brazil, France, Germany, Ghana, Hungary, México, Pakistan, Spain, Slovenia, USA, and UK. In addition to the scientific contribution of the event in bringing together national and international researchers and their work in a strategic area, it helps maintain and strengthen international cooperation for scientific development in Brazil.
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Affiliation(s)
| | - Alexandre Melo Bailão
- Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Alfredo Herrera-Estrella
- Unidad de Genómica Avanzada-Langebio, Centro de Investigación y de Estudios Avanzados Del IPN, Irapuato, Guanajuato, Mexico
| | | | - Attila Gácser
- HCEMM-USZ Fungal Pathogens Research Group, Department of Microbiology, University of Szeged, Szeged, Hungary
| | - Audrey P Gasch
- Center for Genomic Science Innovation, University of Wisconsin Madison, Madison, WI, USA
| | - Claudia B L Campos
- Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo, São José Dos Campos, SP, Brazil
| | - Christina Peters
- Deutsche Forschungsgemeinschaft (DFG), Office Latin America, São Paulo, SP, Brazil
| | - Francine Camelim
- German Academic Exchange Service (DAAD), DWIH, Sao Paulo, SP, Brazil
| | - Fulvia Verde
- Department of Molecular and Cellular Pharmacology, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Geoffrey Michael Gadd
- Geomicrobiology Group, School of Life Sciences, University of Dundee, Dundee, Scotland, UK
| | - Gerhard Braus
- Institute for Microbiology and Genetics, Department of Molecular Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Goettingen, Goettingen, Germany
| | - Iris Eisermann
- The Sainsbury Laboratory, University of East Anglia, Norwich, England, UK
| | - Janet Quinn
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, England, UK
| | - Jean-Paul Latgé
- Institute of Molecular Biology and Biotechnology FORTH and School of Medicine, University of Crete Heraklion, Greece
| | - Jesus Aguirre
- Departamento de Biología Celular y Del Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autonoma de México, Mexico City, Mexico
| | - Joan W Bennett
- Department of Plant Biology, Rutgers, State University of New Jersey, New Brunswick, NJ, USA
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
| | - Joshua D Nosanchuk
- Departments of Medicine and Microbiology and Immunology, Albert Einstein College of Medicine, The Bronx, NY, USA
| | | | - Martine Bassilana
- Institute of Biology Valrose, University Côte D'Azur, CNRS, INSERM, Nice, France
| | | | - Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Mexico
| | - Michael Feldbrügge
- Institute of Microbiology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Nancy P Keller
- Department of Medical Microbiology, Department of Plant Pathology, University of Wisconsin, Madison, WI, USA
| | - Nemat O Keyhani
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, USA
| | - Nina Gunde-Cimerman
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Raquel Nascimento
- Deutsche Forschungsgemeinschaft (DFG), Office Latin America, São Paulo, SP, Brazil
| | - Robert A Arkowitz
- Institute of Biology Valrose, University Côte D'Azur, CNRS, INSERM, Nice, France
| | - Rosa Reyna Mouriño-Pérez
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Mexico
| | - Sehar Afshan Naz
- Lab of Applied Microbiology and Clinical Mycology, Department of Microbiology, Federal Urdu University of Arts, Science and Technology, Gulshan Iqbal, Karachi, Pakistan
| | - Simon V Avery
- School of Life and Environmental Sciences, University of Nottingham, Nottingham, England, UK
| | - Thiago Olitta Basso
- Department of Chemical Engineering, Escola Politécnica, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Ulrich Terpitz
- Department of Biotechnology and Biophysics, Theodor-Boveri-Institute, Biocenter, Julius-Maximilians-Universität Würzburg, Wuerzburg, Germany
| | - Xiaorong Lin
- Department of Microbiology, University of Georgia, Athens, GA, USA
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6
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Eisermann I, Garduño‐Rosales M, Talbot NJ. The emerging role of septins in fungal pathogenesis. Cytoskeleton (Hoboken) 2023; 80:242-253. [PMID: 37265147 PMCID: PMC10952683 DOI: 10.1002/cm.21765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 05/13/2023] [Accepted: 05/16/2023] [Indexed: 06/03/2023]
Abstract
Fungal pathogens undergo specific morphogenetic transitions in order to breach the outer surfaces of plants and invade the underlying host tissue. The ability to change cell shape and switch between non-polarised and polarised growth habits is therefore critical to the lifestyle of plant pathogens. Infection-related development involves remodelling of the cytoskeleton, plasma membrane and cell wall at specific points during fungal pathogenesis. Septin GTPases are components of the cytoskeleton that play pivotal roles in actin remodelling, micron-scale plasma membrane curvature sensing and cell polarity. Septin assemblages, such as rings, collars and gauzes, are known to have important roles in cell shape changes and are implicated in formation of specialised infection structures to enter plant cells. Here, we review and compare the reported functions of septins of plant pathogenic fungi, with a special focus on invasive growth. Finally, we discuss septins as potential targets for broad-spectrum antifungal plant protection strategies.
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Affiliation(s)
- Iris Eisermann
- The Sainsbury LaboratoryUniversity of East AngliaNorwichUK
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Medina-Castellanos E, Salgado-Bautista DA, Martínez-Andrade JM, Cadena-Nava RD, Riquelme M. Nanosized extracellular vesicles released by Neurospora crassa hyphae. Fungal Genet Biol 2023; 165:103778. [PMID: 36690295 DOI: 10.1016/j.fgb.2023.103778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 01/13/2023] [Accepted: 01/17/2023] [Indexed: 01/22/2023]
Abstract
Extracellular vesicles (EVs) are nanosized structures containing proteins, lipids, and nucleic acids, released by living cells to the surrounding medium. EVs participate in diverse processes, such as intercellular communication, virulence, and disease. In pathogenic fungi, EVs carry enzymes that allow them to invade the host or undergo environmental adaptation successfully. In Neurospora crassa, a non-pathogenic filamentous fungus widely used as a model organism, the vesicle-dependent secretory mechanisms that lead to polarized growth are well studied. In contrast, biosynthesis of EVs in this fungus has been practically unexplored. In the present work, we analyzed N. crassa culture's supernatant for the presence of EVs by dynamic light scattering (DLS), transmission electron microscopy (TEM) and proteomic analysis. We identified spherical membranous structures, with a predominant subpopulation averaging a hydrodynamic diameter (dh) of 68 nm and a particle diameter (dp) of 38 nm. EV samples stained with osmium tetroxide vapors were better resolved than those stained with uranyl acetate. Mass spectrometry analysis identified 252 proteins, including enzymes involved in carbohydrate metabolic processes, oxidative stress response, cell wall organization/remodeling, and circadian clock-regulated proteins. Some of these proteins have been previously reported in exosomes from human cells or in EVs of other fungi. In view of the results, it is suggested a putative role for EVs in cell wall biosynthesis and vegetative development in N. crassa.
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Affiliation(s)
- Elizabeth Medina-Castellanos
- Department of Microbiology, Centro de Investigación Científica y Educación Superior de Ensenada (CICESE), Ensenada, Mexico
| | - Daniel A Salgado-Bautista
- Department of Microbiology, Centro de Investigación Científica y Educación Superior de Ensenada (CICESE), Ensenada, Mexico
| | - Juan M Martínez-Andrade
- Department of Microbiology, Centro de Investigación Científica y Educación Superior de Ensenada (CICESE), Ensenada, Mexico
| | - Ruben Dario Cadena-Nava
- Department of Bionanotechnology, Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Ensenada, Mexico
| | - Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y Educación Superior de Ensenada (CICESE), Ensenada, Mexico.
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Pinar M, Alonso A, de los Ríos V, Bravo-Plaza I, de la Gandara Á, Galindo A, Arias-Palomo E, Peñalva MÁ. The type V myosin-containing complex HUM is a RAB11 effector powering movement of secretory vesicles. iScience 2022; 25:104514. [PMID: 35754728 PMCID: PMC9213775 DOI: 10.1016/j.isci.2022.104514] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/28/2022] [Accepted: 05/26/2022] [Indexed: 01/01/2023] Open
Abstract
In the apex-directed RAB11 exocytic pathway of Aspergillus nidulans, kinesin-1/KinA conveys secretory vesicles (SVs) to the hyphal tip, where they are transferred to the type V myosin MyoE. MyoE concentrates SVs at an apical store located underneath the PM resembling the presynaptic active zone. A rod-shaped RAB11 effector, UDS1, and the intrinsically disordered and coiled-coil HMSV associate with MyoE in a stable HUM (HMSV-UDS1-MyoE) complex recruited by RAB11 to SVs through an interaction network involving RAB11 and HUM components, with the MyoE globular tail domain (GTD) binding both HMSV and RAB11-GTP and RAB11-GTP binding both the MyoE-GTD and UDS1. UDS1 bridges RAB11-GTP to HMSV, an avid interactor of the MyoE-GTD. The interaction between the UDS1-HMSV sub-complex and RAB11-GTP can be reconstituted in vitro. Ablating UDS1 or HMSV impairs actomyosin-mediated transport of SVs to the apex, resulting in spreading of RAB11 SVs across the apical dome as KinA/microtubule-dependent transport gains prominence.
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Affiliation(s)
- Mario Pinar
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Ana Alonso
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Vivian de los Ríos
- Proteomics Facility, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Ignacio Bravo-Plaza
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Álvaro de la Gandara
- Department of Chemical and Structural Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Antonio Galindo
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Francis Crick Avenue, CB2 0QH Cambridge, UK
| | - Ernesto Arias-Palomo
- Department of Chemical and Structural Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Miguel Á. Peñalva
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
- Corresponding author
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Spindle Dynamics during Meiotic Development of the Fungus Podospora anserina Requires the Endoplasmic Reticulum-Shaping Protein RTN1. mBio 2021; 12:e0161521. [PMID: 34607459 PMCID: PMC8546617 DOI: 10.1128/mbio.01615-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The endoplasmic reticulum (ER) is an elaborate organelle composed of distinct structural and functional domains. ER structure and dynamics involve membrane-shaping proteins of the reticulon and Yop1/DP1 families, which promote membrane curvature and regulate ER shaping and remodeling. Here, we analyzed the function of the reticulon (RTN1) and Yop1 proteins (YOP1 and YOP2) of the model fungus Podospora anserina and their contribution to sexual development. We found that RTN1 and YOP2 localize to the peripheral ER and are enriched in the dynamic apical ER domains of the polarized growing hyphal region. We discovered that the formation of these domains is diminished in the absence of RTN1 or YOP2 and abolished in the absence of YOP1 and that hyphal growth is moderately reduced when YOP1 is deleted in combination with RTN1 and/or YOP2. In addition, we found that RTN1 associates with the Spitzenkörper. Moreover, RTN1 localization is regulated during meiotic development, where it accumulates at the apex of growing asci (meiocytes) during their differentiation and at their middle region during the subsequent meiotic progression. Furthermore, we discovered that loss of RTN1 affects ascospore (meiotic spore) formation, in a process that does not involve YOP1 or YOP2. Finally, we show that the defects in ascospore formation of rtn1 mutants are associated with defective nuclear segregation and spindle dynamics throughout meiotic development. Our results show that sexual development in P. anserina involves a developmental remodeling of the ER that implicates the reticulon RTN1, which is required for meiotic nucleus segregation.
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Abstract
In a number of elongated cells, such as fungal hyphae, a vesicle cluster is observed at the growing tip. This cluster, called a Spitzenkörper, has been suggested to act as a vesicle supply center, yet analysis of its function is challenging, as a majority of components identified thus far are essential for growth. Here, we probe the function of the Spitzenkörper in the human fungal pathogen Candida albicans, using genetics and synthetic physical interactions (SPI). We show that the C. albicans Spitzenkörper is comprised principally of secretory vesicles. Mutant strains lacking the Spitzenkörper component myosin light chain 1 (Mlc1) or having a SPI between Mlc1 and either another Spitzenkörper component, the Rab GTPase Sec4, or prenylated green fluorescent protein (GFP), are viable and still exhibit a Spitzenkörper during filamentous growth. Strikingly, all of these mutants formed filaments with increased diameters and extension rates, indicating that Mlc1 negatively regulates myosin V, Myo2, activity. The results of our quantitative studies reveal a strong correlation between filament diameter and extension rate, which is consistent with the vesicle supply center model for fungal tip growth. Together, our results indicate that the Spitzenkörper protein Mlc1 is important for growth robustness and reveal a critical link between filament morphology and extension rate. IMPORTANCE Hyphal tip growth is critical in a range of fungal pathogens, in particular for invasion into animal and plant tissues. In Candida albicans, as in many filamentous fungi, a cluster of vesicles, called a Spitzenkörper, is observed at the tip of growing hyphae that is thought to function as a vesicle supply center. A central prediction of the vesicle supply center model is that the filament diameter is proportional to the extension rate. Here, we show that mutants lacking the Spitzenkörper component myosin light chain 1 (Mlc1) or having synthetic physical interactions between Mlc1 and either another Spitzenkörper component or prenylated GFP, are defective in filamentous growth regulation, exhibiting a range of growth rates and sizes, with a strong correlation between diameter and extension rate. These results suggest that the Spitzenkörper is important for growth robustness and reveal a critical link between filament morphology and extension rate.
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Tsuji K, Kitade Y, Sumita T, Tanaka C. An exocyst component, Sec5, is essential for ascospore formation in Bipolaris maydis. MYCOSCIENCE 2021; 62:289-296. [PMID: 37089464 PMCID: PMC9721515 DOI: 10.47371/mycosci.2021.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 05/03/2021] [Accepted: 05/07/2021] [Indexed: 11/16/2022]
Abstract
In this study, we identified Sec5 in Bipolaris maydis, a homologue of Sec5 in Saccharomyces cerevisiae and a possible exocyst component of the fungus. To examine how Sec5 affects the life cycle of B. maydis, we generated null mutant strains of the gene (Δsec5). The Δsec5 strains showed a strong reduction in hyphal growth and a slight reduction in pathogenicity. In sexual reproduction, they possessed the ability to develop pseudothecia. However, all ascospores were aborted in any of the asci obtained from crosses between Δsec5 and the wild-type. Our cytological study revealed that the abortion was caused by impairments of the post-meiotic stages in ascospore development, where ascospore delimitation and young spore elongation occur.
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Affiliation(s)
- Kenya Tsuji
- Graduate School of Agriculture, Kyoto University
| | - Yuki Kitade
- Graduate School of Agriculture, Kyoto University
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The Exocyst Regulates Hydrolytic Enzyme Secretion at Hyphal Tips and Septa in the Banana Fusarium Wilt Fungus Fusarium odoratissimum. Appl Environ Microbiol 2021; 87:e0308820. [PMID: 34132587 DOI: 10.1128/aem.03088-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Hyphal polarized growth in filamentous fungi requires tip-directed secretion, while additional evidence suggests that fungal exocytosis for the hydrolytic enzyme secretion can occur at other sites in hyphae, including the septum. In this study, we analyzed the role of the exocyst complex involved in the secretion in the banana wilt fungal pathogen Fusarium odoratissimum. All eight exocyst components in F. odoratissimum not only localized to the tips ahead of the Spitzenkörper in growing hyphae but also localized to the outer edges of septa in mature hyphae. To further analyze the exocyst in F. odoratissimum, we attempted single gene deletion for all the genes encoding the eight exocyst components and only succeeded in constructing the gene deletion mutants for exo70 and sec5; we suspect that the other 6 exocyst components are encoded by essential genes. Deletion of exo70 or sec5 led to defects in vegetative growth, conidiation, and pathogenicity in F. odoratissimum. Notably, the deletion of exo70 resulted in decreased activities for endoglucosidase, filter paper enzymes, and amylase, while the loss of sec5 only led to a slight reduction in amylase activity. Septum-localized α-amylase (AmyB) was identified as the marker for septum-directed secretion, and we found that Exo70 is essential for the localization of AmyB to septa. Meanwhile the loss of Sec5 did not affect AmyB localization to septa but led to a higher accumulation of AmyB in cytoplasm. This suggested that while Exo70 and Sec5 both take part in the septum-directed secretion, the two play different roles in this process. IMPORTANCE The exocyst complex is a multisubunit tethering complex (MTC) for secretory vesicles at the plasma membrane and contains eight subunits, Sec3, Sec5, Sec6, Sec8, Sec10, Sec15, Exo70, and Exo84. While the exocyst complex is well defined in eukaryotes from yeast (Saccharomyces cerevisiae) to humans, the exocyst components in filamentous fungi show different localization patterns in the apical tips of hyphae, which suggests that filamentous fungi have evolved divergent strategies to regulate endomembrane trafficking. In this study, we demonstrated that the exocyst components in Fusarium odoratissimum are localized not only to the tips of growing hyphae but also to the outer edge of the septa in mature hyphae, suggesting that the exocyst complex plays a role in the regulation of septum-directed protein secretion in F. odoratissimum. We further found that Exo70 and Sec5 are required for the septum-directed secretion of α-amylase in F. odoratissimum but with different influences.
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Something old, something new: challenges and developments in Aspergillus niger biotechnology. Essays Biochem 2021; 65:213-224. [PMID: 33955461 PMCID: PMC8314004 DOI: 10.1042/ebc20200139] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/17/2021] [Accepted: 03/19/2021] [Indexed: 12/12/2022]
Abstract
The filamentous ascomycete fungus Aspergillus niger is a prolific secretor of organic acids, proteins, enzymes and secondary metabolites. Throughout the last century, biotechnologists have developed A. niger into a multipurpose cell factory with a product portfolio worth billions of dollars each year. Recent technological advances, from genome editing to other molecular and omics tools, promise to revolutionize our understanding of A. niger biology, ultimately to increase efficiency of existing industrial applications or even to make entirely new products. However, various challenges to this biotechnological vision, many several decades old, still limit applications of this fungus. These include an inability to tightly control A. niger growth for optimal productivity, and a lack of high-throughput cultivation conditions for mutant screening. In this mini-review, we summarize the current state-of-the-art for A. niger biotechnology with special focus on organic acids (citric acid, malic acid, gluconic acid and itaconic acid), secreted proteins and secondary metabolites, and discuss how new technological developments can be applied to comprehensively address a variety of old and persistent challenges.
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14
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Turning Inside Out: Filamentous Fungal Secretion and Its Applications in Biotechnology, Agriculture, and the Clinic. J Fungi (Basel) 2021; 7:jof7070535. [PMID: 34356914 PMCID: PMC8307877 DOI: 10.3390/jof7070535] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/14/2021] [Accepted: 06/25/2021] [Indexed: 12/15/2022] Open
Abstract
Filamentous fungi are found in virtually every marine and terrestrial habitat. Vital to this success is their ability to secrete a diverse range of molecules, including hydrolytic enzymes, organic acids, and small molecular weight natural products. Industrial biotechnologists have successfully harnessed and re-engineered the secretory capacity of dozens of filamentous fungal species to make a diverse portfolio of useful molecules. The study of fungal secretion outside fermenters, e.g., during host infection or in mixed microbial communities, has also led to the development of novel and emerging technological breakthroughs, ranging from ultra-sensitive biosensors of fungal disease to the efficient bioremediation of polluted environments. In this review, we consider filamentous fungal secretion across multiple disciplinary boundaries (e.g., white, green, and red biotechnology) and product classes (protein, organic acid, and secondary metabolite). We summarize the mechanistic understanding for how various molecules are secreted and present numerous applications for extracellular products. Additionally, we discuss how the control of secretory pathways and the polar growth of filamentous hyphae can be utilized in diverse settings, including industrial biotechnology, agriculture, and the clinic.
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15
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Zamith-Miranda D, Peres da Silva R, Couvillion SP, Bredeweg EL, Burnet MC, Coelho C, Camacho E, Nimrichter L, Puccia R, Almeida IC, Casadevall A, Rodrigues ML, Alves LR, Nosanchuk JD, Nakayasu ES. Omics Approaches for Understanding Biogenesis, Composition and Functions of Fungal Extracellular Vesicles. Front Genet 2021; 12:648524. [PMID: 34012462 PMCID: PMC8126698 DOI: 10.3389/fgene.2021.648524] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 04/06/2021] [Indexed: 12/13/2022] Open
Abstract
Extracellular vesicles (EVs) are lipid bilayer structures released by organisms from all kingdoms of life. The diverse biogenesis pathways of EVs result in a wide variety of physical properties and functions across different organisms. Fungal EVs were first described in 2007 and different omics approaches have been fundamental to understand their composition, biogenesis, and function. In this review, we discuss the role of omics in elucidating fungal EVs biology. Transcriptomics, proteomics, metabolomics, and lipidomics have each enabled the molecular characterization of fungal EVs, providing evidence that these structures serve a wide array of functions, ranging from key carriers of cell wall biosynthetic machinery to virulence factors. Omics in combination with genetic approaches have been instrumental in determining both biogenesis and cargo loading into EVs. We also discuss how omics technologies are being employed to elucidate the role of EVs in antifungal resistance, disease biomarkers, and their potential use as vaccines. Finally, we review recent advances in analytical technology and multi-omic integration tools, which will help to address key knowledge gaps in EVs biology and translate basic research information into urgently needed clinical applications such as diagnostics, and immuno- and chemotherapies to fungal infections.
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Affiliation(s)
- Daniel Zamith-Miranda
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
| | | | - Sneha P. Couvillion
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Erin L. Bredeweg
- Environmental and Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Meagan C. Burnet
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Carolina Coelho
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Emma Camacho
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Leonardo Nimrichter
- Laboratório de Glicobiologia de Eucariotos, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rosana Puccia
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina-Universidade Federal de São Paulo, São Paulo, Brazil
| | - Igor C. Almeida
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Marcio L. Rodrigues
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas-FIOCRUZ PR, Curitiba, Brazil
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lysangela R. Alves
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas-FIOCRUZ PR, Curitiba, Brazil
| | - Joshua D. Nosanchuk
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Ernesto S. Nakayasu
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, United States
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16
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Brejšková L, Hála M, Rawat A, Soukupová H, Cvrčková F, Charlot F, Nogué F, Haluška S, Žárský V. SEC6 exocyst subunit contributes to multiple steps of growth and development of Physcomitrella (Physcomitrium patens). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:831-843. [PMID: 33599020 DOI: 10.1111/tpj.15205] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 12/18/2020] [Accepted: 01/08/2021] [Indexed: 06/12/2023]
Abstract
Spatially directed cell division and expansion is important for plant growth and morphogenesis and relies on cooperation between the cytoskeleton and the secretory pathway. The phylogenetically conserved octameric complex exocyst mediates exocytotic vesicle tethering at the plasma membrane. Unlike other exocyst subunits of land plants, the core exocyst subunit SEC6 exists as a single paralog in Physcomitrium patens and Arabidopsis thaliana genomes. Arabidopsis SEC6 (AtSEC6) loss-of-function (LOF) mutation causes male gametophytic lethality. Our attempts to inactivate the P. patens SEC6 gene, PpSEC6, using targeted gene replacement produced two independent partial LOF ('weak allele') mutants via perturbation of the PpSEC6 gene locus. These mutants exhibited the same pleiotropic developmental defects: protonema with dominant chloronema stage; diminished caulonemal filament elongation rate; and failure in post-initiation gametophore development. Mutant gametophore buds, mostly initiated from chloronema cells, exhibited disordered cell file organization and cross-wall perforations, resulting in arrested development at the eight- to 10-cell stage. Complementation of both sec6 moss mutant lines by both PpSEC6 and AtSEC6 cDNA rescued gametophore development, including sexual organ differentiation. However, regular sporophyte formation and viable spore production were recovered only by the expression of PpSEC6, whereas the AtSEC6 complementants were only rarely fertile, indicating moss-specific SEC6 functions.
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Affiliation(s)
- Lucie Brejšková
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, Prague 6, 165 02, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic
| | - Michal Hála
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, Prague 6, 165 02, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic
| | - Anamika Rawat
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, Prague 6, 165 02, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic
| | - Hana Soukupová
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, Prague 6, 165 02, Czech Republic
| | - Fatima Cvrčková
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic
| | - Florence Charlot
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, 78000, France
| | - Fabien Nogué
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, 78000, France
| | - Samuel Haluška
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, Prague 6, 165 02, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic
| | - Viktor Žárský
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 263, Prague 6, 165 02, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic
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17
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Pinar M, Peñalva MA. The fungal RABOME: RAB GTPases acting in the endocytic and exocytic pathways of Aspergillus nidulans (with excursions to other filamentous fungi). Mol Microbiol 2021; 116:53-70. [PMID: 33724562 DOI: 10.1111/mmi.14716] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/04/2021] [Accepted: 03/11/2021] [Indexed: 10/21/2022]
Abstract
RAB GTPases are major determinants of membrane identity that have been exploited as highly specific reporters to study intracellular traffic in vivo. A score of fungal papers have considered individual RABs, but systematic, integrated studies on the localization and physiological role of these regulators and their effectors have been performed only with Aspergillus nidulans. These studies have influenced the intracellular trafficking field beyond fungal specialists, leading to findings such as the maturation of trans-Golgi (TGN) cisternae into post-Golgi RAB11 secretory vesicles, the concept that these RAB11 secretory carriers are loaded with three molecular nanomotors, the understanding of the role of endocytic recycling mediated by RAB6 and RAB11 in determining the hyphal mode of life, the discovery that early endosome maturation and the ESCRT pathway are essential, the identification of specific adaptors of dynein-dynactin to RAB5 endosomes, the exquisite dependence that autophagy displays on RAB1 activity, the role of TRAPPII as a GEF for RAB11, or the conclusion that the RAB1-to-RAB11 transition is not mediated by TRAPP maturation. A remarkable finding was that the A. nidulans Spitzenkörper contains four RABs: RAB11, Sec4, RAB6, and RAB1. How these RABs cooperate during exocytosis represents an as yet outstanding question.
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Affiliation(s)
- Mario Pinar
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
| | - Miguel A Peñalva
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
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18
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Abstract
Tip-growing fungal cells maintain cell polarity at the apical regions and elongate by de novo synthesis of the cell wall. Cell polarity and tip growth rate affect mycelial morphology. Tip-growing fungal cells maintain cell polarity at the apical regions and elongate by de novo synthesis of the cell wall. Cell polarity and tip growth rate affect mycelial morphology. However, it remains unclear how both features act cooperatively to determine cell shape. Here, we investigated this relationship by analyzing hyphal tip growth of filamentous fungi growing inside extremely narrow 1 μm-width channels of microfluidic devices. Since the channels are much narrower than the diameter of hyphae, any hypha growing through the channel must adapt its morphology. Live-cell imaging analyses revealed that hyphae of some species continued growing through the channels, whereas hyphae of other species often ceased growing when passing through the channels, or had lost apical polarity after emerging from the other end of the channel. Fluorescence live-cell imaging analyses of the Spitzenkörper, a collection of secretory vesicles and polarity-related proteins at the hyphal tip, in Neurospora crassa indicates that hyphal tip growth requires a very delicate balance of ordered exocytosis to maintain polarity in spatially confined environments. We analyzed the mycelial growth of seven fungal species from different lineages, including phytopathogenic fungi. This comparative approach revealed that the growth defects induced by the channels were not correlated with their taxonomic classification or with the width of hyphae, but, rather, correlated with the hyphal elongation rate. This report indicates a trade-off between morphological plasticity and velocity in mycelial growth and serves to help understand fungal invasive growth into substrates or plant/animal cells, with direct impact on fungal biotechnology, ecology, and pathogenicity.
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19
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Xie Y, Miao Y. Polarisome assembly mediates actin remodeling during polarized yeast and fungal growth. J Cell Sci 2021; 134:134/1/jcs247916. [PMID: 33419950 DOI: 10.1242/jcs.247916] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Dynamic assembly and remodeling of actin is critical for many cellular processes during development and stress adaptation. In filamentous fungi and budding yeast, actin cables align in a polarized manner along the mother-to-daughter cell axis, and are essential for the establishment and maintenance of polarity; moreover, they rapidly remodel in response to environmental cues to achieve an optimal system response. A formin at the tip region within a macromolecular complex, called the polarisome, is responsible for driving actin cable polymerization during polarity establishment. This polarisome undergoes dynamic assembly through spatial and temporally regulated interactions between its components. Understanding this process is important to comprehend the tuneable activities of the formin-centered nucleation core, which are regulated through divergent molecular interactions and assembly modes within the polarisome. In this Review, we focus on how intrinsically disordered regions (IDRs) orchestrate the condensation of the polarisome components and the dynamic assembly of the complex. In addition, we address how these components are dynamically distributed in and out of the assembly zone, thereby regulating polarized growth. We also discuss the potential mechanical feedback mechanisms by which the force-induced actin polymerization at the tip of the budding yeast regulates the assembly and function of the polarisome.
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Affiliation(s)
- Ying Xie
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Yansong Miao
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
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20
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Vangalis V, Papaioannou IA, Markakis EA, Knop M, Typas MA. Hex1, the Major Component of Woronin Bodies, Is Required for Normal Development, Pathogenicity, and Stress Response in the Plant Pathogenic Fungus Verticillium dahliae. J Fungi (Basel) 2020; 6:jof6040344. [PMID: 33297524 PMCID: PMC7762394 DOI: 10.3390/jof6040344] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 11/27/2020] [Accepted: 12/03/2020] [Indexed: 12/31/2022] Open
Abstract
Woronin bodies are membrane-bound organelles of filamentous ascomycetes that mediate hyphal compartmentalization by plugging septal pores upon hyphal damage. Their major component is the peroxisomal protein Hex1, which has also been implicated in additional cellular processes in fungi. Here, we analyzed the Hex1 homolog of Verticillium dahliae, an important asexual plant pathogen, and we report its pleiotropic involvement in fungal growth, physiology, stress response, and pathogenicity. Alternative splicing of the Vdhex1 gene can lead to the production of two Hex1 isoforms, which are structurally similar to their Neurospora crassa homolog. We show that VdHex1 is targeted to the septum, consistently with its demonstrated function in sealing hyphal compartments to prevent excessive cytoplasmic bleeding upon injury. Furthermore, our investigation provides direct evidence for significant contributions of Hex1 in growth and morphogenesis, as well as in asexual reproduction capacity. We discovered that Hex1 is required both for normal responses to osmotic stress and factors that affect the cell wall and plasma-membrane integrity, and for normal resistance to oxidative stress and reactive oxygen species (ROS) homeostasis. The Vdhex1 mutant exhibited diminished ability to colonize and cause disease on eggplant. Overall, we show that Hex1 has fundamentally important multifaceted roles in the biology of V. dahliae.
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Affiliation(s)
- Vasileios Vangalis
- Department of Genetics & Biotechnology, Faculty of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece;
| | - Ioannis A. Papaioannou
- Center for Molecular Biology, Heidelberg University (ZMBH), 69120 Heidelberg, Germany; (I.A.P.); (M.K.)
| | - Emmanouil A. Markakis
- Laboratory of Mycology, Department of Viticulture, Vegetable Crops, Floriculture and Plant Protection, Institute of Olive Tree, Subtropical Crops and Viticulture, N.A.G.R.E.F., Hellenic Agricultural Organization—DEMETER, 71307 Heraklion, Crete, Greece;
| | - Michael Knop
- Center for Molecular Biology, Heidelberg University (ZMBH), 69120 Heidelberg, Germany; (I.A.P.); (M.K.)
- German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Milton A. Typas
- Department of Genetics & Biotechnology, Faculty of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece;
- Correspondence:
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21
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Ma Z, Chen Z, Wang W, Wang K, Zhu T. Exocyst subunit BcSec3 regulates growth, development and pathogenicity in Botrytis cinerea. J Biosci 2020. [DOI: 10.1007/s12038-020-00097-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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22
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Peñalva MA, Moscoso‐Romero E, Hernández‐González M. Tracking exocytosis of aGPI‐anchored protein inAspergillus nidulans. Traffic 2020; 21:675-688. [DOI: 10.1111/tra.12761] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/04/2020] [Accepted: 09/07/2020] [Indexed: 12/26/2022]
Affiliation(s)
- Miguel A. Peñalva
- Department of Cellular and Molecular Biology Centro de Investigaciones Biológicas CSIC Madrid Spain
| | - Esteban Moscoso‐Romero
- Department of Cellular and Molecular Biology Centro de Investigaciones Biológicas CSIC Madrid Spain
- Morphogenesis and Cell Polarity Unit Instituto de Biología Funcional y Genómica CSIC‐Universidad de Salamanca Salamanca Spain
| | - Miguel Hernández‐González
- Department of Cellular and Molecular Biology Centro de Investigaciones Biológicas CSIC Madrid Spain
- The Francis Crick Institute London UK
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23
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Roberson RW. Subcellular structure and behaviour in fungal hyphae. J Microsc 2020; 280:75-85. [PMID: 32700404 DOI: 10.1111/jmi.12945] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/13/2020] [Accepted: 07/20/2020] [Indexed: 12/15/2022]
Abstract
This work briefly surveys the diversity of selected subcellular characteristics in hyphal tip cells of the fungal kingdom (Mycota). Hyphae are filamentous cells that grow by tip extension. It is a highly polarised mechanism that requires a robust secretory system for the delivery of materials (e.g. membrane, proteins, cell wall materials) to sites of cell growth. These events result it the self-assembly of a Spitzenkörper (Spk), found most often in the Basidiomycota, Ascomycota, and Blastocladiomycota, or an apical vesicle crescent (AVC), present in the most Mucoromycota and Zoopagomycota. The Spk is a complex apical body composed of secretory vesicles, cytoskeletal elements, and signaling proteins. The AVC appears less complex, though little is known of its composition other than secretory vesicles. Both bodies influence hyphal growth and morphogenesis. Other factors such as cytoskeletal functions, endocytosis, cytoplasmic flow, and turgor pressure are also important in sustaining hyphal growth. Clarifying subcellular structures, functions, and behaviours through bioimagining analysis are providing a better understanding of the cell biology and phylogenetic relationships of fungi. LAY DESCRIPTION: Fungi are most familiar to the public as yeast, molds, and mushrooms. They are eukaryotic organisms that inhabit diverse ecological niches around the world and are critical to the health of ecosystems performing roles in decomposition of organic matter and nutrient recycling (Heath, 1990). Fungi are heterotrophs, unlike plants, and comprise the most successful and diverse phyla of eukaryotic microbes, interacting with all other forms of life in associations that range from beneficial (e.g., mycorrhizae) to antagonistic (e.g., pathogens). Some fungi can be parasitic or pathogenic on plants (e.g., Cryphonectria parasitica, Magnaporthe grisea), insects (e.g., Beauveria bassiana, Cordyceps sp.), invertebrates (e.g., Drechslerella anchonia), vertebrates (e.g., Coccidioides immitis, Candia albicans) and other fungi (e.g., Trichoderma viride, Ampelomyces quisqualis). The majority of fungi, however, are saprophytes, obtaining nutrition through the brake down of non-living organic matter.
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Affiliation(s)
- R W Roberson
- School of Life Sciences, Arizona State University, Tempe, Arizona, U.S.A
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24
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Spitzenkörper assembly mechanisms reveal conserved features of fungal and metazoan polarity scaffolds. Nat Commun 2020; 11:2830. [PMID: 32503980 PMCID: PMC7275032 DOI: 10.1038/s41467-020-16712-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 05/14/2020] [Indexed: 02/08/2023] Open
Abstract
The Spitzenkörper (SPK) constitutes a collection of secretory vesicles and polarity-related proteins intimately associated with polarized growth of fungal hyphae. Many SPK-localized proteins are known, but their assembly and dynamics remain poorly understood. Here, we identify protein-protein interaction cascades leading to assembly of two SPK scaffolds and recruitment of diverse effectors in Neurospora crassa. Both scaffolds are transported to the SPK by the myosin V motor (MYO-5), with the coiled-coil protein SPZ-1 acting as cargo adaptor. Neither scaffold appears to be required for accumulation of SPK secretory vesicles. One scaffold consists of Leashin-2 (LAH-2), which is required for SPK localization of the signalling kinase COT-1 and the glycolysis enzyme GPI-1. The other scaffold comprises a complex of Janus-1 (JNS-1) and the polarisome protein SPA-2. Via its Spa homology domain (SHD), SPA-2 recruits a calponin domain-containing F-actin effector (CCP-1). The SHD NMR structure reveals a conserved surface groove required for effector binding. Similarities between SPA-2/JNS-1 and the metazoan GIT/PIX complex identify foundational features of the cell polarity apparatus that predate the fungal-metazoan divergence. The Spitzenkörper (SPK) is a polarized accumulation of proteins and secretory vesicles associated with tip growth of fungal hyphae. Here, Zheng et al. study SPK assembly and dynamics, identify SPK protein scaffolds and associated proteins, and reveal similarities with other scaffolds from metazoans.
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25
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de Jong TG, Hulshof J, Prokert G. Modelling fungal hypha tip growth via viscous sheet approximation. J Theor Biol 2020; 492:110189. [PMID: 32035095 DOI: 10.1016/j.jtbi.2020.110189] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 01/03/2020] [Accepted: 02/04/2020] [Indexed: 02/03/2023]
Abstract
In this paper we present a new model for single-celled, non-branching hypha tip growth. The growth mechanism of hypha cells consists of transport of cell wall building material to the cell wall and subsequent incorporation of this material in the wall as it arrives. To model the transport of cell wall building material to the cell wall we follow Bartnicki-Garcia and Gierz in assuming that the cell wall building material is transported in straight lines by an isotropic point source. To model the dynamics of the cell wall, including its growth by new material, we use the approach of Campàs and Mahadevan, which assumes that the cell wall is a thin viscous sheet sustained by a pressure difference. Furthermore, we include a novel equation which models the hardening of the cell wall as it ages. We validate the new model by comparing it to experimental data.
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Affiliation(s)
- T G de Jong
- Media Analytics and Computing laboratory, School of Information Science and Engineering, Xiamen University, Xiamen 361005, China
| | - J Hulshof
- Department of Mathematics, Faculty of Sciences VU University Amsterdam, De Boelelaan 1105, HV Amsterdam 1081, the Netherlands.
| | - G Prokert
- Center for Analysis, Scientific Computing and Applications (CASA), TU Eindhoven, P.O Box 513, Eindhoven, the Netherlands.
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26
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Ganesan SJ, Feyder MJ, Chemmama IE, Fang F, Rout MP, Chait BT, Shi Y, Munson M, Sali A. Integrative structure and function of the yeast exocyst complex. Protein Sci 2020; 29:1486-1501. [PMID: 32239688 DOI: 10.1002/pro.3863] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/25/2020] [Accepted: 03/27/2020] [Indexed: 12/13/2022]
Abstract
Exocyst is an evolutionarily conserved hetero-octameric tethering complex that plays a variety of roles in membrane trafficking, including exocytosis, endocytosis, autophagy, cell polarization, cytokinesis, pathogen invasion, and metastasis. Exocyst serves as a platform for interactions between the Rab, Rho, and Ral small GTPases, SNARE proteins, and Sec1/Munc18 regulators that coordinate spatial and temporal fidelity of membrane fusion. However, its mechanism is poorly described at the molecular level. Here, we determine the molecular architecture of the yeast exocyst complex by an integrative approach, based on a 3D density map from negative-stain electron microscopy (EM) at ~16 Å resolution, 434 disuccinimidyl suberate and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride cross-links from chemical-crosslinking mass spectrometry, and partial atomic models of the eight subunits. The integrative structure is validated by a previously determined cryo-EM structure, cross-links, and distances from in vivo fluorescence microscopy. Our subunit configuration is consistent with the cryo-EM structure, except for Sec5. While not observed in the cryo-EM map, the integrative model localizes the N-terminal half of Sec3 near the Sec6 subunit. Limited proteolysis experiments suggest that the conformation of Exo70 is dynamic, which may have functional implications for SNARE and membrane interactions. This study illustrates how integrative modeling based on varied low-resolution structural data can inform biologically relevant hypotheses, even in the absence of high-resolution data.
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Affiliation(s)
- Sai J Ganesan
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
| | - Michael J Feyder
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Ilan E Chemmama
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
| | - Fei Fang
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, New York, USA
| | - Brian T Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, New York, USA
| | - Yi Shi
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Mary Munson
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
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27
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Li FGM, Liu W, Bai Y, Tao T, Wang Y, Zhang J, Luo H, Yao B, Huang H, Su X, Su X. RNAi-Mediated Gene Silencing of Trcot1 Induces a Hyperbranching Phenotype in Trichoderma reesei. J Microbiol Biotechnol 2020; 30:206-215. [PMID: 31752060 PMCID: PMC9728278 DOI: 10.4014/jmb.1909.09050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Trichoderma reesei is the major filamentous fungus used to produce cellulase and there is huge interest in promoting its ability to produce higher titers of cellulase. Among the many factors affecting cellulase production in T. reesei, the mycelial phenotype is important but seldom studied. Herein, a close homolog of the Neurospora crassa COT1 kinase was discovered in T. reesei and designated TrCOT1, which is of 83.3% amino acid sequence identity. Functional disruption of Trcot1 in T. reesei by RNAi-mediated gene silencing resulted in retarded sporulation on potato dextrose agar and dwarfed colonies on minimal medium agar plates containing glucose, xylan, lactose, xylose, or glycerol as the sole carbon source. The representative mutant strain, SUS2/Trcot1i, also displayed reduced mycelia accumulation but hyperbranching in the MM glucose liquid medium, with hyphal growth unit length values decreased to 73.0 µm/tip compared to 239.8 µm/tip for the parent strain SUS2. The hyperbranching phenotype led to slightly but significantly increased cellulase secretion from 24 to 72 h in a batch culture. However, the cellulase production per unit of mycelial biomass was much more profoundly improved from 24 to 96 h.
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Affiliation(s)
- Fei Gao Mengzhu Li
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 0008, P.R. China,College of Biological Sciences, China Agricultural University, Beijing 100193, P.R, China
| | - Weiquan Liu
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 0008, P.R. China
| | - Yingguo Bai
- College of Biological Sciences, China Agricultural University, Beijing 100193, P.R, China
| | - Tu Tao
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 0008, P.R. China
| | - Yuan Wang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 0008, P.R. China
| | - Jie Zhang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 0008, P.R. China
| | - Huiying Luo
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 0008, P.R. China
| | - Bin Yao
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 0008, P.R. China
| | - Huoqing Huang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 0008, P.R. China,Corresponding authors H.H. Phone: +86-10-82106065 E-mail:
| | - Xiaoyun Su
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 0008, P.R. China,X.S. Phone: +86-10-82106094 E-mail:
| | - Xiaoyun Su
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, P.R. China
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28
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Callejas-Negrete OA, Castro-Longoria E. The role of GYP-3 in cellular morphogenesis of Neurospora crassa: Analyzing its relationship with the polarisome. Fungal Genet Biol 2019; 128:49-59. [DOI: 10.1016/j.fgb.2019.04.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 04/03/2019] [Accepted: 04/03/2019] [Indexed: 12/18/2022]
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29
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Cairns TC, Zheng X, Zheng P, Sun J, Meyer V. Moulding the mould: understanding and reprogramming filamentous fungal growth and morphogenesis for next generation cell factories. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:77. [PMID: 30988699 PMCID: PMC6446404 DOI: 10.1186/s13068-019-1400-4] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 03/09/2019] [Indexed: 05/21/2023]
Abstract
Filamentous fungi are harnessed as cell factories for the production of a diverse range of organic acids, proteins, and secondary metabolites. Growth and morphology have critical implications for product titres in both submerged and solid-state fermentations. Recent advances in systems-level understanding of the filamentous lifestyle and development of sophisticated synthetic biological tools for controlled manipulation of fungal genomes now allow rational strain development programs based on data-driven decision making. In this review, we focus on Aspergillus spp. and other industrially utilised fungi to summarise recent insights into the multifaceted and dynamic relationship between filamentous growth and product titres from genetic, metabolic, modelling, subcellular, macromorphological and process engineering perspectives. Current progress and knowledge gaps with regard to mechanistic understanding of product secretion and export from the fungal cell are discussed. We highlight possible strategies for unlocking lead genes for rational strain optimizations based on omics data, and discuss how targeted genetic manipulation of these candidates can be used to optimise fungal morphology for improved performance. Additionally, fungal signalling cascades are introduced as critical processes that can be genetically targeted to control growth and morphology during biotechnological applications. Finally, we review progress in the field of synthetic biology towards chassis cells and minimal genomes, which will eventually enable highly programmable filamentous growth and diversified production capabilities. Ultimately, these advances will not only expand the fungal biotechnology portfolio but will also significantly contribute to a sustainable bio-economy.
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Affiliation(s)
- Timothy C. Cairns
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 People’s Republic of China
| | - Xiaomei Zheng
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 People’s Republic of China
| | - Ping Zheng
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 People’s Republic of China
| | - Jibin Sun
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
- Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 People’s Republic of China
| | - Vera Meyer
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
- Department of Applied and Molecular Microbiology, Institute of Biotechnology, Technische Universität Berlin, 13355 Berlin, Germany
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30
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Sun X, Su X. Harnessing the knowledge of protein secretion for enhanced protein production in filamentous fungi. World J Microbiol Biotechnol 2019; 35:54. [PMID: 30900052 DOI: 10.1007/s11274-019-2630-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 03/08/2019] [Indexed: 12/19/2022]
Abstract
Filamentous fungi are important microorganisms used in industrial production of proteins and enzymes. Among these organisms, Trichoderma reesei, Aspergilli, and more recently Myceliophthora thermophile are the most widely used and promising ones which have powerful protein secretion capability. In recent years, there have been tremendous achievements in understanding the molecular mechanisms of the secretory pathways in filamentous fungi. The acquired pieces of knowledge can be harnessed to enhance protein production in filamentous fungi with assistance of state-of-the-art genetic engineering techniques.
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Affiliation(s)
- Xianhua Sun
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 South Zhongguancun Street, Beijing, 100081, China
| | - Xiaoyun Su
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 South Zhongguancun Street, Beijing, 100081, China.
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31
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Verdín J, Sánchez-León E, Rico-Ramírez AM, Martínez-Núñez L, Fajardo-Somera RA, Riquelme M. Off the wall: The rhyme and reason of Neurospora crassa hyphal morphogenesis. ACTA ACUST UNITED AC 2019; 5:100020. [PMID: 32743136 PMCID: PMC7389182 DOI: 10.1016/j.tcsw.2019.100020] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 02/07/2019] [Accepted: 02/10/2019] [Indexed: 12/11/2022]
Abstract
Chitin and β-1,3-glucan synthases are transported separately in chitosomes and macrovesicles. Chitin synthases occupy the core of the SPK; β-1,3-glucan synthases the outer layer. CHS-4 arrival to the SPK and septa is CSE-7 dependent. Rabs YPT-1 and YPT-31 localization at the SPK mimics that of chitosomes and macrovesicles. The exocyst acts as a tether between the SPK outer layer vesicles and the apical PM.
The fungal cell wall building processes are the ultimate determinants of hyphal shape. In Neurospora crassa the main cell wall components, β-1,3-glucan and chitin, are synthesized by enzymes conveyed by specialized vesicles to the hyphal tip. These vesicles follow different secretory routes, which are delicately coordinated by cargo-specific Rab GTPases until their accumulation at the Spitzenkörper. From there, the exocyst mediates the docking of secretory vesicles to the plasma membrane, where they ultimately get fused. Although significant progress has been done on the cellular mechanisms that carry cell wall synthesizing enzymes from the endoplasmic reticulum to hyphal tips, a lot of information is still missing. Here, the current knowledge on N. crassa cell wall composition and biosynthesis is presented with an emphasis on the underlying molecular and cellular secretory processes.
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Key Words
- BGT, β-1,3-glucan transferases
- CHS, chitin synthase
- CLSM, confocal laser scanning microscopy
- CWI, cell wall integrity
- CWP, cell wall proteins
- Cell wall
- ER, endoplasmic reticulum
- FRAP, fluorescence recovery after photobleaching
- GEF, guanine nucleotide exchange factor
- GFP, green fluorescent protein
- GH, glycosyl hydrolases
- GPI, glycosylphosphatidylinositol
- GSC, β-1,3-glucan synthase complex
- MMD, myosin-like motor domain
- MS, mass spectrometry
- MT, microtubule
- NEC, network of elongated cisternae
- PM, plasma membrane
- SPK, Spitzenkörper
- Spitzenkörper
- TIRFM, total internal reflection fluorescence microscopy
- TM, transmembrane
- Tip growth
- Vesicles
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Affiliation(s)
- Jorge Verdín
- Industrial Biotechnology, CIATEJ-Jalisco State Scientific Research and Technology Assistance Center, Mexico National Council for Science and Technology, Zapopan, Jalisco, Mexico
| | - Eddy Sánchez-León
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
| | - Adriana M Rico-Ramírez
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, CICESE Ensenada, Baja California, Mexico
| | - Leonora Martínez-Núñez
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Rosa A Fajardo-Somera
- Karlsruhe Institute of Technology (KIT) South Campus, Institute for Applied Biosciences, Department of Microbiology, Karlsruhe, Germany
| | - Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, CICESE Ensenada, Baja California, Mexico
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32
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Takeshita N. Control of Actin and Calcium for Chitin Synthase Delivery to the Hyphal Tip of Aspergillus. Curr Top Microbiol Immunol 2019; 425:113-129. [PMID: 31974757 DOI: 10.1007/82_2019_193] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Filamentous fungi are covered by a cell wall consisting mainly of chitin and glucan. The synthesis of chitin, a β-1,4-linked homopolymer of N-acetylglucosamine, is essential for hyphal morphogenesis. Fungal chitin synthases are integral membrane proteins that have been classified into seven classes. ChsB, a class III chitin synthase, is known to play a key role in hyphal tip growth and has been used here as a model to understand the cell biology of cell wall biosynthesis in Aspergillus nidulans. Chitin synthases are transported on secretory vesicles to the plasma membrane for new cell wall synthesis. Super-resolution localization imaging as a powerful biophysical approach indicated dynamics of the Spitzenkörper where spatiotemporally regulated exocytosis and cell extension, whereas high-speed pulse-chase imaging has revealed ChsB transport mechanism mediated by kinesin-1 and myosin-5. In addition, live imaging analysis showed correlations among intracellular Ca2+ levels, actin assembly, and exocytosis in growing hyphal tips. This suggests that pulsed Ca2+ influxes coordinate the temporal control of actin assembly and exocytosis, which results in stepwise cell extension. It is getting clear that turgor pressure and cell wall pressure are involved in the activation of Ca2+ channels for Ca2+ oscillation and cell extension. Here the cell wall synthesis and tip growth meet again.
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Affiliation(s)
- Norio Takeshita
- Microbiology Research Center for Sustainability (MiCS), Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan.
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33
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Lepore DM, Martínez-Núñez L, Munson M. Exposing the Elusive Exocyst Structure. Trends Biochem Sci 2018; 43:714-725. [PMID: 30055895 PMCID: PMC6108956 DOI: 10.1016/j.tibs.2018.06.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Revised: 06/18/2018] [Accepted: 06/29/2018] [Indexed: 11/18/2022]
Abstract
A major challenge for a molecular understanding of membrane trafficking has been the elucidation of high-resolution structures of large, multisubunit tethering complexes that spatially and temporally control intracellular membrane fusion. Exocyst is a large hetero-octameric protein complex proposed to tether secretory vesicles at the plasma membrane to provide quality control of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE)-mediated membrane fusion. Breakthroughs in methodologies, including sample preparation, biochemical characterization, fluorescence microscopy, and single-particle cryoelectron microscopy, are providing critical insights into the structure and function of the exocyst. These studies now pose more questions than answers for understanding fundamental functional mechanisms, and they open wide the door for future studies to elucidate interactions with protein and membrane partners, potential conformational changes, and molecular insights into tethering reactions.
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Affiliation(s)
- Dante M Lepore
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA
| | - Leonora Martínez-Núñez
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA
| | - Mary Munson
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA.
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Riquelme M, Aguirre J, Bartnicki-García S, Braus GH, Feldbrügge M, Fleig U, Hansberg W, Herrera-Estrella A, Kämper J, Kück U, Mouriño-Pérez RR, Takeshita N, Fischer R. Fungal Morphogenesis, from the Polarized Growth of Hyphae to Complex Reproduction and Infection Structures. Microbiol Mol Biol Rev 2018; 82:e00068-17. [PMID: 29643171 PMCID: PMC5968459 DOI: 10.1128/mmbr.00068-17] [Citation(s) in RCA: 183] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Filamentous fungi constitute a large group of eukaryotic microorganisms that grow by forming simple tube-like hyphae that are capable of differentiating into more-complex morphological structures and distinct cell types. Hyphae form filamentous networks by extending at their tips while branching in subapical regions. Rapid tip elongation requires massive membrane insertion and extension of the rigid chitin-containing cell wall. This process is sustained by a continuous flow of secretory vesicles that depends on the coordinated action of the microtubule and actin cytoskeletons and the corresponding motors and associated proteins. Vesicles transport cell wall-synthesizing enzymes and accumulate in a special structure, the Spitzenkörper, before traveling further and fusing with the tip membrane. The place of vesicle fusion and growth direction are enabled and defined by the position of the Spitzenkörper, the so-called cell end markers, and other proteins involved in the exocytic process. Also important for tip extension is membrane recycling by endocytosis via early endosomes, which function as multipurpose transport vehicles for mRNA, septins, ribosomes, and peroxisomes. Cell integrity, hyphal branching, and morphogenesis are all processes that are largely dependent on vesicle and cytoskeleton dynamics. When hyphae differentiate structures for asexual or sexual reproduction or to mediate interspecies interactions, the hyphal basic cellular machinery may be reprogrammed through the synthesis of new proteins and/or the modification of protein activity. Although some transcriptional networks involved in such reprogramming of hyphae are well studied in several model filamentous fungi, clear connections between these networks and known determinants of hyphal morphogenesis are yet to be established.
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Affiliation(s)
- Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Jesús Aguirre
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Salomon Bartnicki-García
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics and Goettingen Center for Molecular Biosciences (GZMB), University of Goettingen, Goettingen, Germany
| | - Michael Feldbrügge
- Institute for Microbiology, Heinrich Heine University Düsseldorf, Cluster of Excellence on Plant Sciences, Düsseldorf, Germany
| | - Ursula Fleig
- Institute for Functional Genomics of Microorganisms, Heinrich Heine University Düsseldorf, Cluster of Excellence on Plant Sciences, Düsseldorf, Germany
| | - Wilhelm Hansberg
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Alfredo Herrera-Estrella
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, Mexico
| | - Jörg Kämper
- Karlsruhe Institute of Technology-South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | - Ulrich Kück
- Ruhr University Bochum, Lehrstuhl für Allgemeine und Molekulare Botanik, Bochum, Germany
| | - Rosa R Mouriño-Pérez
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Norio Takeshita
- University of Tsukuba, Faculty of Life and Environmental Sciences, Tsukuba, Japan
| | - Reinhard Fischer
- Karlsruhe Institute of Technology-South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
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35
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Fiedler MRM, Cairns TC, Koch O, Kubisch C, Meyer V. Conditional Expression of the Small GTPase ArfA Impacts Secretion, Morphology, Growth, and Actin Ring Position in Aspergillus niger. Front Microbiol 2018; 9:878. [PMID: 29867795 PMCID: PMC5952172 DOI: 10.3389/fmicb.2018.00878] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 04/16/2018] [Indexed: 12/26/2022] Open
Abstract
In filamentous fungi, growth and protein secretion occurs predominantly at the tip of long, thread like cells termed hyphae. This requires coordinated regulation of multiple processes, including vesicle trafficking, exocytosis, and endocytosis, which are facilitated by a complex cytoskeletal apparatus. In this study, functional analyses of the small GTPase ArfA from Aspergillus niger demonstrate that this protein functionally complements the Saccharomyces cerevisiae ARF1/2, and that this protein is essential for A. niger. Loss-of-function and gain-of-function analyses demonstrate that titration of arfA expression impacts hyphal growth rate, hyphal tip morphology, and protein secretion. Moreover, localization of the endocytic machinery, visualized via fluorescent tagging of the actin ring, was found to be abnormal in ArfA under- and overexpressed conditions. Finally, we provide evidence that the major secreted protein GlaA localizes at septal junctions, indicating that secretion in A. niger may occur at these loci, and that this process is likely impacted by arfA expression levels. Taken together, our results demonstrate that ArfA fulfills multiple functions in the secretory pathway of A. niger.
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Affiliation(s)
- Markus R M Fiedler
- Department of Applied and Molecular Microbiology, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Timothy C Cairns
- Department of Applied and Molecular Microbiology, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Oliver Koch
- Department of Applied and Molecular Microbiology, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Christin Kubisch
- Department of Applied and Molecular Microbiology, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Vera Meyer
- Department of Applied and Molecular Microbiology, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
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36
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Hernández-González M, Bravo-Plaza I, Pinar M, de los Ríos V, Arst HN, Peñalva MA. Endocytic recycling via the TGN underlies the polarized hyphal mode of life. PLoS Genet 2018; 14:e1007291. [PMID: 29608571 PMCID: PMC5880334 DOI: 10.1371/journal.pgen.1007291] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 03/06/2018] [Indexed: 12/13/2022] Open
Abstract
Intracellular traffic in Aspergillus nidulans hyphae must cope with the challenges that the high rates of apical extension (1μm/min) and the long intracellular distances (>100 μm) impose. Understanding the ways in which the hyphal tip cell coordinates traffic to meet these challenges is of basic importance, but is also of considerable applied interest, as fungal invasiveness of animals and plants depends critically upon maintaining these high rates of growth. Rapid apical extension requires localization of cell-wall-modifying enzymes to hyphal tips. By combining genetic blocks in different trafficking steps with multidimensional epifluorescence microscopy and quantitative image analyses we demonstrate that polarization of the essential chitin-synthase ChsB occurs by indirect endocytic recycling, involving delivery/exocytosis to apices followed by internalization by the sub-apical endocytic collar of actin patches and subsequent trafficking to TGN cisternae, where it accumulates for ~1 min before being re-delivered to the apex by a RAB11/TRAPPII-dependent pathway. Accordingly, ChsB is stranded at the TGN by Sec7 inactivation but re-polarizes to the apical dome if the block is bypassed by a mutation in geaAgea1 that restores growth in the absence of Sec7. That polarization is independent of RAB5, that ChsB predominates at apex-proximal cisternae, and that upon dynein impairment ChsB is stalled at the tips in an aggregated endosome indicate that endocytosed ChsB traffics to the TGN via sorting endosomes functionally located upstream of the RAB5 domain and that this step requires dynein-mediated basipetal transport. It also requires RAB6 and its effector GARP (Vps51/Vps52/Vps53/Vps54), whose composition we determined by MS/MS following affinity chromatography purification. Ablation of any GARP component diverts ChsB to vacuoles and impairs growth and morphology markedly, emphasizing the important physiological role played by this pathway that, we propose, is central to the hyphal mode of growth. Filamentous fungi form long tubular cells, called hyphae, which grow rapidly by apical extension, enabling these sessile organisms to explore substrates and facilitating tissue invasion in the case of pathogenic species. Because the shape of the hyphae is determined by an external cell wall, hyphal growth requires that cell-wall sculpting enzymes polarize to the tips. Endocytosis is essential for hyphal growth, and it was suspected that this results from its participation in a recycling pathway that takes up cell-wall enzymes from the plasma membrane and re-delivers them to the apex. Here we track the trafficking of a chitin synthase (a cell-wall modifying enzyme) to demonstrate that it is polarized by endocytic recycling. This chitin synthase is delivered by exocytosis to the apex, but diffuses away until being captured by a subapical collar of actin patches (sites of endocytosis) from where it reaches a sorting endosome before undergoing transport to the nearest trans-Golgi cisternae and incorporating into secretory vesicles that re-deliver the enzyme to the apex. Because impairing transit across this pathway compromises apical extension markedly and results in severe morphological defects, the pathway could be manipulated to prevent fungal pathogenicity of plants and humans, an enormous burden on human welfare.
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Affiliation(s)
- Miguel Hernández-González
- Department of Cellular and Molecular Biology and Intradepartmental WhiteBiotech Unit, Centro de Investigaciones Biológicas del Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, Madrid, Spain
| | - Ignacio Bravo-Plaza
- Department of Cellular and Molecular Biology and Intradepartmental WhiteBiotech Unit, Centro de Investigaciones Biológicas del Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, Madrid, Spain
| | - Mario Pinar
- Department of Cellular and Molecular Biology and Intradepartmental WhiteBiotech Unit, Centro de Investigaciones Biológicas del Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, Madrid, Spain
| | - Vivian de los Ríos
- Proteomics Facility, Centro de Investigaciones Biológicas del Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, Madrid, Spain
| | - Herbert N. Arst
- Section of Microbiology, Imperial College London, Flowers Building, Armstrong Road, London, United Kingdom
| | - Miguel A. Peñalva
- Department of Cellular and Molecular Biology and Intradepartmental WhiteBiotech Unit, Centro de Investigaciones Biológicas del Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, Madrid, Spain
- * E-mail:
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Rico-Ramírez AM, Roberson RW, Riquelme M. Imaging the secretory compartments involved in the intracellular traffic of CHS-4, a class IV chitin synthase, in Neurospora crassa. Fungal Genet Biol 2018; 117:30-42. [PMID: 29601947 DOI: 10.1016/j.fgb.2018.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 03/25/2018] [Accepted: 03/26/2018] [Indexed: 12/16/2022]
Abstract
In Neurospora crassa hyphae the localization of all seven chitin synthases (CHSs) at the Spitzenkörper (SPK) and at developing septa has been well analyzed. Hitherto, the mechanisms of CHSs traffic and sorting from synthesis to delivery sites remain largely unexplored. In Saccharomyces cerevisiae exit of Chs3p from the endoplasmic reticulum (ER) requires chaperone Chs7p. Here, we analyzed the role of CSE-7, N. crassa Chs7p orthologue, in the biogenesis of CHS-4 (orthologue of Chs3p). In a N. crassa Δcse-7 mutant, CHS-4-GFP no longer accumulated at the SPK and septa. Instead, fluorescence was retained in hyphal subapical regions in an extensive network of elongated cisternae (NEC) referred to previously as tubular vacuoles. In a complemented strain expressing a copy of cse-7 the localization of CHS-4-GFP at the SPK and septa was restored, providing evidence that CSE-7 is necessary for the localization of CHS-4 at hyphal tips and septa. CSE-7 was revealed at delimited regions of the ER at the immediacies of nuclei, at the NEC, and remarkably also at septa and the SPK. The organization of the NEC was dependent on the cytoskeleton. SEC-63, an extensively used ER marker, and NCA-1, a SERCA-type ATPase previously localized at the nuclear envelope, were used as markers to discern the nature of the membranes containing CSE-7. Both SEC-63 and NCA-1 were found at the nuclear envelope, but also at regions of the NEC. However, at the NEC only NCA-1 co-localized extensively with CSE-7. Observations by transmission electron microscopy revealed abundant rough ER sheets and distinct electron translucent smooth flattened cisternae, which could correspond collectively to the NEC, thorough the subapical cytoplasm. This study identifies CSE-7 as the putative ER receptor for its cognate cargo, the polytopic membrane protein CHS-4, and elucidates the complexity of the ER system in filamentous fungi.
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Affiliation(s)
- Adriana M Rico-Ramírez
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, BC 22860, Mexico
| | | | - Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, BC 22860, Mexico.
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Jung EM, Kothe E, Raudaskoski M. The making of a mushroom: Mitosis, nuclear migration and the actin network. Fungal Genet Biol 2018; 111:85-91. [DOI: 10.1016/j.fgb.2017.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 11/07/2017] [Accepted: 11/08/2017] [Indexed: 10/18/2022]
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van Gisbergen PAC, Wu SZ, Chang M, Pattavina KA, Bartlett ME, Bezanilla M. An ancient Sec10-formin fusion provides insights into actin-mediated regulation of exocytosis. J Cell Biol 2018; 217:945-957. [PMID: 29374070 PMCID: PMC5839782 DOI: 10.1083/jcb.201705084] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 12/21/2017] [Accepted: 01/08/2018] [Indexed: 11/22/2022] Open
Abstract
Interactions between actin nucleators and the exocyst in yeast and mammals control membrane remodeling. van Gisbergen et al. now describe For1F, a fusion of an exocyst subunit (Sec10) and an actin nucleation factor (formin), retained in the moss lineage for more than 170 million years, which provides unique insight into the regulation of exocytosis by actin. Exocytosis, facilitated by the exocyst, is fundamentally important for remodeling cell walls and membranes. Here, we analyzed For1F, a novel gene that encodes a fusion of an exocyst subunit (Sec10) and an actin nucleation factor (formin). We showed that the fusion occurred early in moss evolution and has been retained for more than 170 million years. In Physcomitrella patens, For1F is essential, and the expressed protein is a fusion of Sec10 and formin. Reduction of For1F or actin filaments inhibits exocytosis, and For1F dynamically associates with Sec6, another exocyst subunit, in an actin-dependent manner. Complementation experiments demonstrate that constitutive expression of either half of the gene or the paralogous Sec10b rescues loss of For1F, suggesting that fusion of the two domains is not essential, consistent with findings in yeast, where formin and the exocyst are linked noncovalently. Although not essential, the fusion may have had selective advantages and provides a unique opportunity to probe actin regulation of exocytosis.
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Affiliation(s)
| | - Shu-Zon Wu
- Biological Sciences Department, Dartmouth College, Hanover, NH
| | - Mingqin Chang
- Biological Sciences Department, Dartmouth College, Hanover, NH.,Plant Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA
| | - Kelli A Pattavina
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA
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Connolly LR, Erlendson AA, Fargo CM, Jackson KK, Pelker MMG, Mazzola JW, Geisler MS, Freitag M. Application of the Cre/lox System to Construct Auxotrophic Markers for Quantitative Genetic Analyses in Fusarium graminearum. Methods Mol Biol 2018; 1848:235-263. [PMID: 30182239 DOI: 10.1007/978-1-4939-8724-5_16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The bacteriophage P1 Cre/lox system has been utilized in diverse fungi for marker recycling and exchange, generation of targeted chromosome translocations, and targeted deletion of interstitial chromosome segments. Here we show the application of this tool in the wheat and maize pathogen, Fusarium graminearum. We explored three different ways to introduce Cre into strains with floxed genes, namely transformation with an episomal or integrative plasmid (pLC28), fusion of protoplasts of strains carrying floxed genes with strains expressing Cre by forcing heterokaryons, and crosses between strains with floxed genes and strains expressing Cre to isolate progeny in which the target genes had been deleted during the cross. We used this system for the construction of strains bearing auxotrophic markers that were generated by gene replacement with positively selectable markers followed by Cre-mediated marker excision. In addition, updated protocols for transformation and crosses for F. graminearum are provided. In combination, strains and tools developed here add to the arsenal of methods that can be used to carry out molecular genetics with F. graminearum.
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Affiliation(s)
- Lanelle R Connolly
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, USA
| | - Allyson A Erlendson
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, USA
| | - Corinne M Fargo
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, USA
| | - Kendra K Jackson
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, USA
| | - Morgan M G Pelker
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, USA
| | - Jacob W Mazzola
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, USA
| | - Mark S Geisler
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, USA
| | - Michael Freitag
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, USA.
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41
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Oscillatory fungal cell growth. Fungal Genet Biol 2017; 110:10-14. [PMID: 29229585 DOI: 10.1016/j.fgb.2017.12.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 11/26/2017] [Accepted: 12/06/2017] [Indexed: 12/20/2022]
Abstract
Cells are dynamic systems, the state of which undergoes constant alteration that results in morphological changes and movement. Many dynamic cellular processes that appear continuous are driven by underlying mechanisms that oscillate with distinct periods. For example eukaryotic cells do not grow continuously, but rather by pulsed extension of the periphery. Stepwise cell extension at the hyphal tips of several filamentous fungi was discovered 20 years ago, but only a few molecular details of the mechanism have been clarified since then. A recent study has provided evidence for correlations among intracellular Ca2+ levels, actin assembly, exocytosis and cell extension in growing hyphal tips. This suggests that pulsed Ca2+ influxes coordinate the temporal control of actin assembly and exocytosis, which results in stepwise cell extension. The coordinated oscillation of these machineries are likely to be ubiquitous among all eukaryotes. Indeed, intracellular Ca2+ levels and/or actin polymerization oscillate in mammalian and plant cells. This review summarizes the mechanisms of oscillation in several systems.
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Abstract
Filamentous fungi are a large and ancient clade of microorganisms that occupy a broad range of ecological niches. The success of filamentous fungi is largely due to their elongate hypha, a chain of cells, separated from each other by septa. Hyphae grow by polarized exocytosis at the apex, which allows the fungus to overcome long distances and invade many substrates, including soils and host tissues. Hyphal tip growth is initiated by establishment of a growth site and the subsequent maintenance of the growth axis, with transport of growth supplies, including membranes and proteins, delivered by motors along the cytoskeleton to the hyphal apex. Among the enzymes delivered are cell wall synthases that are exocytosed for local synthesis of the extracellular cell wall. Exocytosis is opposed by endocytic uptake of soluble and membrane-bound material into the cell. The first intracellular compartment in the endocytic pathway is the early endosomes, which emerge to perform essential additional functions as spatial organizers of the hyphal cell. Individual compartments within septated hyphae can communicate with each other via septal pores, which allow passage of cytoplasm or organelles to help differentiation within the mycelium. This article introduces the reader to more detailed aspects of hyphal growth in fungi.
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Abstract
Filamentous fungi have proven to be a better-suited model system than unicellular yeasts in analyses of cellular processes such as polarized growth, exocytosis, endocytosis, and cytoskeleton-based organelle traffic. For example, the filamentous fungus
Neurospora crassa develops a variety of cellular forms. Studying the molecular basis of these forms has led to a better, yet incipient, understanding of polarized growth. Polarity factors as well as Rho GTPases, septins, and a localized delivery of vesicles are the central elements described so far that participate in the shift from isotropic to polarized growth. The growth of the cell wall by apical biosynthesis and remodeling of polysaccharide components is a key process in hyphal morphogenesis. The coordinated action of motor proteins and Rab GTPases mediates the vesicular journey along the hyphae toward the apex, where the exocyst mediates vesicle fusion with the plasma membrane. Cytoplasmic microtubules and actin microfilaments serve as tracks for the transport of vesicular carriers as well as organelles in the tubular cell, contributing to polarization. In addition to exocytosis, endocytosis is required to set and maintain the apical polarity of the cell. Here, we summarize some of the most recent breakthroughs in hyphal morphogenesis and apical growth in
N. crassa and the emerging questions that we believe should be addressed.
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Affiliation(s)
- Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Baja California, 22860, Mexico
| | - Leonora Martínez-Núñez
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Baja California, 22860, Mexico
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Schultzhaus Z, Johnson TB, Shaw BD. Clathrin localization and dynamics in Aspergillus nidulans. Mol Microbiol 2016; 103:299-318. [PMID: 27741567 DOI: 10.1111/mmi.13557] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/10/2016] [Indexed: 12/15/2022]
Abstract
Cell growth necessitates extensive membrane remodeling events including vesicle fusion or fission, processes that are regulated by coat proteins. The hyphal cells of filamentous fungi concentrate both exocytosis and endocytosis at the apex. This investigation focuses on clathrin in Aspergillus nidulans, with the aim of understanding its role in membrane remodeling in growing hyphae. We examined clathrin heavy chain (ClaH-GFP) which localized to three distinct subcellular structures: late Golgi (trans-Golgi equivalents of filamentous fungi), which are concentrated just behind the hyphal tip but are intermittently present throughout all hyphal cells; the region of concentrated endocytosis just behind the hyphal apex (the "endocytic collar"); and small, rapidly moving puncta that were seen trafficking long distances in nearly all hyphal compartments. ClaH localized to distinct domains on late Golgi, and these clathrin "hubs" dispersed in synchrony after the late Golgi marker PHOSBP . Although clathrin was essential for growth, ClaH did not colocalize well with the endocytic patch marker fimbrin. Tests of FM4-64 internalization and repression of ClaH corroborated the observation that clathrin does not play an important role in endocytosis in A. nidulans. A minor portion of ClaH puncta exhibited bidirectional movement, likely along microtubules, but were generally distinct from early endosomes.
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Affiliation(s)
- Z Schultzhaus
- Department of Plant Pathology and Microbiology, Texas A&M University, 2132 TAMU, College Station, TX, 77845, USA
| | - T B Johnson
- Department of Plant Pathology and Microbiology, Texas A&M University, 2132 TAMU, College Station, TX, 77845, USA
| | - B D Shaw
- Department of Plant Pathology and Microbiology, Texas A&M University, 2132 TAMU, College Station, TX, 77845, USA
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Johansen J, Alfaro G, Beh CT. Polarized Exocytosis Induces Compensatory Endocytosis by Sec4p-Regulated Cortical Actin Polymerization. PLoS Biol 2016; 14:e1002534. [PMID: 27526190 PMCID: PMC4985162 DOI: 10.1371/journal.pbio.1002534] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 07/21/2016] [Indexed: 11/18/2022] Open
Abstract
Polarized growth is maintained by both polarized exocytosis, which transports membrane components to specific locations on the cell cortex, and endocytosis, which retrieves these components before they can diffuse away. Despite functional links between these two transport pathways, they are generally considered to be separate events. Using live cell imaging, in vivo and in vitro protein binding assays, and in vitro pyrene-actin polymerization assays, we show that the yeast Rab GTPase Sec4p couples polarized exocytosis with cortical actin polymerization, which induces endocytosis. After polarized exocytosis to the plasma membrane, Sec4p binds Las17/Bee1p (yeast Wiskott-Aldrich Syndrome protein [WASp]) in a complex with Sla1p and Sla2p during actin patch assembly. Mutations that inactivate Sec4p, or its guanine nucleotide exchange factor (GEF) Sec2p, inhibit actin patch formation, whereas the activating sec4-Q79L mutation accelerates patch assembly. In vitro assays of Arp2/3-dependent actin polymerization established that GTPγS-Sec4p overrides Sla1p inhibition of Las17p-dependent actin nucleation. These results support a model in which Sec4p relocates along the plasma membrane from polarized sites of exocytic vesicle fusion to nascent sites of endocytosis. Activated Sec4p then promotes actin polymerization and triggers compensatory endocytosis, which controls surface expansion and kinetically refines cell polarization.
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Affiliation(s)
- Jesper Johansen
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Gabriel Alfaro
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Christopher T. Beh
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
- Centre for Cell Biology, Development, and Disease, Simon Fraser University, Burnaby, British Columbia, Canada
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46
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Lin C, Schuster M, Guimaraes SC, Ashwin P, Schrader M, Metz J, Hacker C, Gurr SJ, Steinberg G. Active diffusion and microtubule-based transport oppose myosin forces to position organelles in cells. Nat Commun 2016; 7:11814. [PMID: 27251117 PMCID: PMC4895713 DOI: 10.1038/ncomms11814] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 05/03/2016] [Indexed: 11/26/2022] Open
Abstract
Even distribution of peroxisomes (POs) and lipid droplets (LDs) is critical to their role in lipid and reactive oxygen species homeostasis. How even distribution is achieved remains elusive, but diffusive motion and directed motility may play a role. Here we show that in the fungus Ustilago maydis ∼95% of POs and LDs undergo diffusive motions. These movements require ATP and involve bidirectional early endosome motility, indicating that microtubule-associated membrane trafficking enhances diffusion of organelles. When early endosome transport is abolished, POs and LDs drift slowly towards the growing cell end. This pole-ward drift is facilitated by anterograde delivery of secretory cargo to the cell tip by myosin-5. Modelling reveals that microtubule-based directed transport and active diffusion support distribution, mobility and mixing of POs. In mammalian COS-7 cells, microtubules and F-actin also counteract each other to distribute POs. This highlights the importance of opposing cytoskeletal forces in organelle positioning in eukaryotes. The mechanisms underlying the positioning of eukaryotic organelles remain elusive. Here Lin et al. use imaging and a mathematical model to show that microtubule-based transport and active diffusion and actin-based polar drift act together to facilitate even distribution of peroxisomes in filamentous fungi.
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Affiliation(s)
- Congping Lin
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK.,Mathematics, University of Exeter, North Park Road, Exeter EX4 4QF, UK
| | - Martin Schuster
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | | | - Peter Ashwin
- Mathematics, University of Exeter, North Park Road, Exeter EX4 4QF, UK
| | - Michael Schrader
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Jeremy Metz
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Christian Hacker
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Sarah Jane Gurr
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Gero Steinberg
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
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Bergs A, Ishitsuka Y, Evangelinos M, Nienhaus GU, Takeshita N. Dynamics of Actin Cables in Polarized Growth of the Filamentous Fungus Aspergillus nidulans. Front Microbiol 2016; 7:682. [PMID: 27242709 PMCID: PMC4860496 DOI: 10.3389/fmicb.2016.00682] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 04/26/2016] [Indexed: 12/20/2022] Open
Abstract
Highly polarized growth of filamentous fungi requires a continuous supply of proteins and lipids to the hyphal tip. This transport is managed by vesicle trafficking via the actin and microtubule cytoskeletons and their associated motor proteins. Particularly, actin cables originating from the hyphal tip are essential for hyphal growth. Although, specific marker proteins have been developed to visualize actin cables in filamentous fungi, the exact organization and dynamics of actin cables has remained elusive. Here, we observed actin cables using tropomyosin (TpmA) and Lifeact fused to fluorescent proteins in living Aspergillus nidulans hyphae and studied the dynamics and regulation. GFP tagged TpmA visualized dynamic actin cables formed from the hyphal tip with cycles of elongation and shrinkage. The elongation and shrinkage rates of actin cables were similar and approximately 0.6 μm/s. Comparison of actin markers revealed that high concentrations of Lifeact reduced actin dynamics. Simultaneous visualization of actin cables and microtubules suggests temporally and spatially coordinated polymerization and depolymerization between the two cytoskeletons. Our results provide new insights into the molecular mechanism of ordered polarized growth regulated by actin cables and microtubules.
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Affiliation(s)
- Anna Bergs
- Department of Microbiology, Institute for Applied Bioscience, Karlsruhe Institute of Technology Karlsruhe, Germany
| | - Yuji Ishitsuka
- Institute of Applied Physics, Karlsruhe Institute of Technology Karlsruhe, Germany
| | - Minoas Evangelinos
- Department of Microbiology, Institute for Applied Bioscience, Karlsruhe Institute of TechnologyKarlsruhe, Germany; Faculty of Biology, University of AthensAthens, Greece
| | - G U Nienhaus
- Institute of Applied Physics, Karlsruhe Institute of TechnologyKarlsruhe, Germany; Institute of Toxicology and Genetics, Karlsruhe Institute of TechnologyEggenstein-Leopoldshafen, Germany; Institute of Nanotechnology, Karlsruhe Institute of TechnologyEggenstein-Leopoldshafen, Germany; Department of Physics, University of Illinois at Urbana-ChampaignUrbana-Champaign, IL, USA
| | - Norio Takeshita
- Department of Microbiology, Institute for Applied Bioscience, Karlsruhe Institute of TechnologyKarlsruhe, Germany; Faculty of Life and Environmental Sciences, University of TsukubaTsukuba, Japan
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48
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Abstract
Filamentous fungi are extremely polarized organisms, exhibiting continuous growth at their hyphal tips. The hyphal form is related to their pathogenicity in animals and plants, and their high secretion ability for biotechnology. Polarized growth requires a sequential supply of proteins and lipids to the hyphal tip. This transport is managed by vesicle trafficking via the actin and microtubule cytoskeleton. Therefore, the arrangement of the cytoskeleton is a crucial step to establish and maintain the cell polarity. This review summarizes recent findings unraveling the mechanism of polarized growth with special emphasis on the role of actin and microtubule cytoskeleton and polarity marker proteins. Rapid insertions of membranes via highly active exocytosis at hyphal tips could quickly dilute the accumulated polarity marker proteins. Recent findings by a super-resolution microscopy indicate that filamentous fungal cells maintain their polarity at the tips by repeating transient assembly and disassembly of polarity sites.
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Affiliation(s)
- Norio Takeshita
- a Department of Microbiology , Institute for Applied Bioscience, Karlsruhe Institute of Technology (KIT) , Karlsruhe , Germany.,b Faculty of Life and Environmental Sciences , University of Tsukuba , Tsukuba , Japan
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49
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Martin-Urdiroz M, Deeks MJ, Horton CG, Dawe HR, Jourdain I. The Exocyst Complex in Health and Disease. Front Cell Dev Biol 2016; 4:24. [PMID: 27148529 PMCID: PMC4828438 DOI: 10.3389/fcell.2016.00024] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 03/11/2016] [Indexed: 01/23/2023] Open
Abstract
Exocytosis involves the fusion of intracellular secretory vesicles with the plasma membrane, thereby delivering integral membrane proteins to the cell surface and releasing material into the extracellular space. Importantly, exocytosis also provides a source of lipid moieties for membrane extension. The tethering of the secretory vesicle before docking and fusion with the plasma membrane is mediated by the exocyst complex, an evolutionary conserved octameric complex of proteins. Recent findings indicate that the exocyst complex also takes part in other intra-cellular processes besides secretion. These various functions seem to converge toward defining a direction of membrane growth in a range of systems from fungi to plants and from neurons to cilia. In this review we summarize the current knowledge of exocyst function in cell polarity, signaling and cell-cell communication and discuss implications for plant and animal health and disease.
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Affiliation(s)
| | - Michael J Deeks
- Biosciences, College of Life and Environmental Sciences, University of Exeter Exeter, UK
| | - Connor G Horton
- Biosciences, College of Life and Environmental Sciences, University of Exeter Exeter, UK
| | - Helen R Dawe
- Biosciences, College of Life and Environmental Sciences, University of Exeter Exeter, UK
| | - Isabelle Jourdain
- Biosciences, College of Life and Environmental Sciences, University of Exeter Exeter, UK
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50
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Guo M, Kilaru S, Schuster M, Latz M, Steinberg G. Fluorescent markers for the Spitzenkörper and exocytosis in Zymoseptoria tritici. Fungal Genet Biol 2016; 79:158-65. [PMID: 26092802 PMCID: PMC4502456 DOI: 10.1016/j.fgb.2015.04.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 04/10/2015] [Accepted: 04/13/2015] [Indexed: 11/25/2022]
Abstract
We establish Z. tritici polarity markers ZtSec4, ZtMlc1, ZtRab11, ZtExo70 and ZtSpa2. All markers localize correctly, labeling the Spitzenkörper and sites of polar exocytosis. We provide 5 carboxin-resistance conveying vectors for integration of all markers into the sdi1 locus. We provide 5 hygromycin B-resistance conveying vectors for random integration of all markers.
Fungal hyphae are highly polarized cells that invade their substrate by tip growth. In plant pathogenic fungi, hyphal growth is essential for host invasion. This makes polarity factors and secretion regulators potential new targets for novel fungicides. Polarization requires delivery of secretory vesicles to the apical Spitzenkörper, followed by polarized exocytosis at the expanding cell tip. Here, we introduce fluorescent markers to visualize the apical Spitzenkörper and the apical site of exocytosis in hyphae of the wheat pathogen Zymoseptoria tritici. We fused green fluorescent protein to the small GTPase ZtSec4, the myosin light chain ZtMlc1 and the small GTPase ZtRab11 and co-localize the fusion proteins with the dye FM4-64 in the hyphal apex, suggesting that the markers label the hyphal Spitzenkörper in Z. tritici. In addition, we localize GFP-fusions to the exocyst protein ZtExo70, the polarisome protein ZtSpa2. Consistent with results in the ascomycete Neurospora crassa, these markers did localize near the plasma membrane at the hyphal tip and only partially co-localize with FM4-64. Thus, these fluorescent markers are useful molecular tools that allow phenotypic analysis of mutants in Z. tritici. These tools will help develop new avenues of research in our quest to control STB infection in wheat.
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Affiliation(s)
- M Guo
- School of Biosciences, University of Exeter, Exeter EX4 4QD, UK
| | - S Kilaru
- School of Biosciences, University of Exeter, Exeter EX4 4QD, UK
| | - M Schuster
- School of Biosciences, University of Exeter, Exeter EX4 4QD, UK
| | - M Latz
- School of Biosciences, University of Exeter, Exeter EX4 4QD, UK
| | - G Steinberg
- School of Biosciences, University of Exeter, Exeter EX4 4QD, UK.
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