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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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Bittner E, Stehlik T, Freitag J. Sharing the wealth: The versatility of proteins targeted to peroxisomes and other organelles. Front Cell Dev Biol 2022; 10:934331. [PMID: 36225313 PMCID: PMC9549241 DOI: 10.3389/fcell.2022.934331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 07/27/2022] [Indexed: 11/13/2022] Open
Abstract
Peroxisomes are eukaryotic organelles with critical functions in cellular energy and lipid metabolism. Depending on the organism, cell type, and developmental stage, they are involved in numerous other metabolic and regulatory pathways. Many peroxisomal functions require factors also relevant to other cellular compartments. Here, we review proteins shared by peroxisomes and at least one different site within the cell. We discuss the mechanisms to achieve dual targeting, their regulation, and functional consequences. Characterization of dual targeting is fundamental to understand how peroxisomes are integrated into the metabolic and regulatory circuits of eukaryotic cells.
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Ramírez-Cota R, Espino-Vazquez AN, Carolina Rodriguez-Vega T, Evelyn Macias-Díaz R, Alicia Callejas-Negrete O, Freitag M, Fischer R, Roberson RW, Mouriño-Pérez RR. The cytoplasmic microtubule array in Neurospora crassa depends on microtubule-organizing centers at spindle pole bodies and microtubule +end-depending pseudo-MTOCs at septa. Fungal Genet Biol 2022; 162:103729. [DOI: 10.1016/j.fgb.2022.103729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 07/22/2022] [Accepted: 07/25/2022] [Indexed: 11/16/2022]
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4
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Barata-Antunes C, Talaia G, Broutzakis G, Ribas D, De Beule P, Casal M, Stefan CJ, Diallinas G, Paiva S. Interactions of cytosolic tails in the Jen1 carboxylate transporter are critical for trafficking and transport activity. J Cell Sci 2022; 135:275079. [PMID: 35437607 DOI: 10.1242/jcs.260059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 04/05/2022] [Indexed: 12/26/2022] Open
Abstract
Plasma membrane (PM) transporters of the major facilitator superfamily (MFS) are essential for cell metabolism, growth and response to stress or drugs. In Saccharomyces cerevisiae, Jen1 is a monocarboxylate/H+ symporter that provides a model to dissect the molecular details underlying cellular expression, transport mechanism and turnover of MFS transporters. Here, we present evidence revealing novel roles of the cytosolic N- and C-termini of Jen1 in its biogenesis, PM stability and transport activity, using functional analyses of Jen1 truncations and chimeric constructs with UapA, an endocytosis-insensitive transporter of Aspergillus nidulans. Our results show that both N- and C-termini are critical for Jen1 trafficking to the PM, transport activity and endocytosis. Importantly, we provide evidence that Jen1 N- and C-termini undergo transport-dependent dynamic intramolecular interactions, which affect the transport activity and turnover of Jen1. Our results support an emerging concept where the cytoplasmic termini of PM transporters control transporter cell surface stability and function through flexible intramolecular interactions with each other. These findings might be extended to other MFS members to understand conserved and evolving mechanisms underlying transporter structure-function relationships. This article has an associated First Person interview with the first authors of the paper.
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Affiliation(s)
- Cláudia Barata-Antunes
- Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, 4710-057, Braga, Portugal.,Institute of Science and Innovation for Bio-Sustainability (IB-S), University of Minho, 4710-057, Braga, Portugal
| | - Gabriel Talaia
- Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, 4710-057, Braga, Portugal.,Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA
| | - George Broutzakis
- Department of Biology, National and Kapodistrian University of Athens, Panepistimiopolis 15784, Athens, Greece
| | - David Ribas
- Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, 4710-057, Braga, Portugal
| | - Pieter De Beule
- International Iberian Nanotechnology Laboratory, Avenida Mestre José Veiga s/n, Braga, Portugal
| | - Margarida Casal
- Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, 4710-057, Braga, Portugal.,Institute of Science and Innovation for Bio-Sustainability (IB-S), University of Minho, 4710-057, Braga, Portugal
| | - Christopher J Stefan
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - George Diallinas
- Department of Biology, National and Kapodistrian University of Athens, Panepistimiopolis 15784, Athens, Greece.,Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, 70013, Heraklion, Greece
| | - Sandra Paiva
- Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, 4710-057, Braga, Portugal.,Institute of Science and Innovation for Bio-Sustainability (IB-S), University of Minho, 4710-057, Braga, Portugal
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5
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Wernet V, Wäckerle J, Fischer R. The STRIPAK component SipC is involved in morphology and cell-fate determination in the nematode-trapping fungus Duddingtonia flagrans. Genetics 2022; 220:iyab153. [PMID: 34849851 PMCID: PMC8733638 DOI: 10.1093/genetics/iyab153] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 08/20/2021] [Indexed: 11/29/2022] Open
Abstract
The striatin-interacting phosphatase and kinase (STRIPAK) complex is a highly conserved eukaryotic signaling hub involved in the regulation of many cellular processes. In filamentous fungi, STRIPAK controls multicellular development, hyphal fusion, septation, and pathogenicity. In this study, we analyzed the role of the STRIPAK complex in the nematode-trapping fungus Duddingtonia flagrans which forms three-dimensional, adhesive trapping networks to capture Caenorhabditis elegans. Trap networks consist of several hyphal loops which are morphologically and functionally different from vegetative hyphae. We show that lack of the STRIPAK component SipC (STRIP1/2/HAM-2/PRO22) results in incomplete loop formation and column-like trap structures with elongated compartments. The misshapen or incomplete traps lost their trap identity and continued growth as vegetative hyphae. The same effect was observed in the presence of the actin cytoskeleton drug cytochalasin A. These results could suggest a link between actin and STRIPAK complex functions.
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Affiliation(s)
- Valentin Wernet
- Department of Microbiology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT)—South Campus, D-76131 Karlsruhe, Germany
| | - Jan Wäckerle
- Department of Microbiology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT)—South Campus, D-76131 Karlsruhe, Germany
| | - Reinhard Fischer
- Department of Microbiology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT)—South Campus, D-76131 Karlsruhe, Germany
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6
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Gao X, Herrero S, Wernet V, Erhardt S, Valerius O, Braus GH, Fischer R. The role of Aspergillus nidulans polo-like kinase PlkA in microtubule-organizing center control. J Cell Sci 2021; 134:271867. [PMID: 34328180 DOI: 10.1242/jcs.256537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 07/19/2021] [Indexed: 11/20/2022] Open
Abstract
Centrosomes are important microtubule-organizing centers (MTOC) in animal cells. In addition, non-centrosomal MTOCs (ncMTOCs) have been described in many cell types. The functional analogs of centrosomes in fungi are the spindle pole bodies (SPBs). In Aspergillus nidulans, additional MTOCs have been discovered at septa (sMTOC). Although the core components are conserved in both MTOCs, their composition and organization are different and dynamic. Here, we show that the polo-like kinase PlkA binds the γ-tubulin ring complex (γ-TuRC) receptor protein ApsB and contributes to targeting ApsB to both MTOCs. PlkA coordinates the activities of the SPB outer plaque and the sMTOC. PlkA kinase activity was required for astral MT formation involving ApsB recruitment. PlkA also interacted with the γ-TuRC inner plaque receptor protein PcpA. Mitosis was delayed without PlkA, and the PlkA protein was required for proper mitotic spindle morphology, although this function was independent of its catalytic activity. Our results suggest that the polo-like kinase is a regulator of MTOC activities and acts as a scaffolding unit through interaction with γ-TuRC receptors.
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Affiliation(s)
- Xiaolei Gao
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Saturnino Herrero
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Valentin Wernet
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Sylvia Erhardt
- Karlsruhe Institute of Technology (KIT) - South Campus, Zoological Institute, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Oliver Valerius
- University of Göttingen, Dept. of Microbiology, Justus-von-Liebig-Weg 11 37077 Göttingen, Germany
| | - Gerhard H Braus
- University of Göttingen, Dept. of Microbiology, Justus-von-Liebig-Weg 11 37077 Göttingen, Germany
| | - Reinhard Fischer
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
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7
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Gao X, Fischer R, Takeshita N. Application of PALM Superresolution Microscopy to the Analysis of Microtubule-Organizing Centers (MTOCs) in Aspergillus nidulans. Methods Mol Biol 2021; 2329:277-289. [PMID: 34085230 DOI: 10.1007/978-1-0716-1538-6_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Photoactivated localization microscopy (PALM), one of the super resolution microscopy methods improving the resolution limit to 20 nm, allows the detection of single molecules in complex protein structures in living cells. Microtubule-organizing centres (MTOCs) are large, multisubunit protein complexes, required for microtubule polymerization. The prominent MTOC in higher eukaryotes is the centrosome, and its functional ortholog in fungi is the spindle-pole body (SPB). There is ample evidence that besides centrosomes other MTOCs are important in eukaryotic cells. The filamentous ascomycetous fungus Aspergillus nidulans is a model organism, with hyphae consisting of multinucleate compartments separated by septa. In A. nidulans, besides the SPBs, a second type of MTOCs was discovered at septa (called septal MTOCs, sMTOC). All the MTOC components appear as big dots at SPBs and sMTOCs when tagged with a fluorescent protein and observed with conventional fluorescence microscopy due to the diffraction barrier. In this chapter, we describe the application of PALM in quantifying the numbers of individual proteins at both MTOC sites in A. nidulans and provide evidence that the composition of MTOCs is highly dynamic and dramatically changes during the cell cycle.
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Affiliation(s)
- Xiaolei Gao
- Department of Microbiology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Reinhard Fischer
- Department of Microbiology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Norio Takeshita
- Microbiology Research Center for Sustainability (MiCS), Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan.
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8
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Gao X, Schmid M, Zhang Y, Fukuda S, Takeshita N, Fischer R. The spindle pole body of Aspergillus nidulans is asymmetrical and contains changing numbers of γ-tubulin complexes. J Cell Sci 2019; 132:jcs.234799. [PMID: 31740532 DOI: 10.1242/jcs.234799] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 10/28/2019] [Indexed: 12/14/2022] Open
Abstract
Centrosomes are important microtubule-organizing centers (MTOCs) in animal cells. In addition, non-centrosomal MTOCs (ncMTOCs) are found in many cell types. Their composition and structure are only poorly understood. Here, we analyzed nuclear MTOCs (spindle-pole bodies, SPBs) and septal MTOCs in Aspergillus nidulans They both contain γ-tubulin along with members of the family of γ-tubulin complex proteins (GCPs). Our data suggest that SPBs consist of γ-tubulin small complexes (γ-TuSCs) at the outer plaque, and larger γ-tubulin ring complexes (γ-TuRC) at the inner plaque. We show that the MztA protein, an ortholog of the human MOZART protein (also known as MZT1), interacted with the inner plaque receptor PcpA (the homolog of fission yeast Pcp1) at SPBs, while no interaction nor colocalization was detected between MztA and the outer plaque receptor ApsB (fission yeast Mto1). Septal MTOCs consist of γ-TuRCs including MztA but are anchored through AspB and Spa18 (fission yeast Mto2). MztA is not essential for viability, although abnormal spindles were observed frequently in cells lacking MztA. Quantitative PALM imaging revealed unexpected dynamics of the protein composition of SPBs, with changing numbers of γ-tubulin complexes over time during interphase and constant numbers during mitosis.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Xiaolei Gao
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Marjorie Schmid
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Ying Zhang
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Sayumi Fukuda
- Tsukuba University, Faculty of Life and Environmental Sciences, Tsukuba 305-8572, Japan
| | - Norio Takeshita
- Tsukuba University, Faculty of Life and Environmental Sciences, Tsukuba 305-8572, Japan
| | - Reinhard Fischer
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
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9
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Qiu R, Zhang J, Xiang X. LIS1 regulates cargo-adapter-mediated activation of dynein by overcoming its autoinhibition in vivo. J Cell Biol 2019; 218:3630-3646. [PMID: 31562232 PMCID: PMC6829669 DOI: 10.1083/jcb.201905178] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 08/08/2019] [Accepted: 08/29/2019] [Indexed: 02/08/2023] Open
Abstract
Deficiency of the LIS1 protein causes lissencephaly, a brain developmental disorder. Although LIS1 binds the microtubule motor cytoplasmic dynein and has been linked to dynein function in many experimental systems, its mechanism of action remains unclear. Here, we revealed its function in cargo-adapter-mediated dynein activation in the model organism Aspergillus nidulans Specifically, we found that overexpressed cargo adapter HookA (Hook in A. nidulans) missing its cargo-binding domain (ΔC-HookA) causes dynein and its regulator dynactin to relocate from the microtubule plus ends to the minus ends, and this relocation requires LIS1 and its binding protein, NudE. Astonishingly, the requirement for LIS1 or NudE can be bypassed to a significant extent by mutations that prohibit dynein from forming an autoinhibited conformation in which the motor domains of the dynein dimer are held close together. Our results suggest a novel mechanism of LIS1 action that promotes the switch of dynein from the autoinhibited state to an open state to facilitate dynein activation.
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Affiliation(s)
- Rongde Qiu
- Department of Biochemistry and Molecular Biology, the Uniformed Services University F. Edward Hébert School of Medicine, Bethesda, MD
| | - Jun Zhang
- Department of Biochemistry and Molecular Biology, the Uniformed Services University F. Edward Hébert School of Medicine, Bethesda, MD
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, the Uniformed Services University F. Edward Hébert School of Medicine, Bethesda, MD
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Zhao X, Yang X, Lu Z, Wang H, He Z, Zhou G, Luo Z, Zhang Y. MADS-box transcription factor Mcm1 controls cell cycle, fungal development, cell integrity and virulence in the filamentous insect pathogenic fungus Beauveria bassiana. Environ Microbiol 2019; 21:3392-3416. [PMID: 30972885 DOI: 10.1111/1462-2920.14629] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 04/09/2019] [Indexed: 12/15/2022]
Abstract
MADS-box transcription factor Mcm1 plays crucial roles in regulating mating processes and pathogenesis in some fungi. However, its roles are varied in fungal species, and its function remains unclear in entomopathogenic fungi. Here, Mcm1 orthologue, Bbmcm1, was characterized in a filamentous entomopathogenic fungus, Beauveria bassiana. Disruption of Bbmcm1 resulted in a distinct reduction in growth with abnormal conidiogenesis, and a significant decrease in conidial viability with abnormal germination. ΔBbmcm1 displayed impaired cell integrity, with distorted cell wall structure and altered cell wall component. Abnormal cell cycle was detected in ΔBbmcm1 with longer G2 /M phase but shorter G1 /G0 and S phases in unicellular blastospores, and sparser septa in multicellular hyphae, which might be responsible for defects in development and differentiation due to the regulation of cell cycle-involved genes, as well as the corresponding cellular events-associated genes. Dramatically decreased virulence was examined in ΔBbmcm1, with impaired ability to escape haemocyte encapsulation, which was consistent with markedly reduced cuticle-degrading enzyme production by repressing their coding genes, and downregulated fungal effector protein-coding genes, suggesting a novel role of Mcm1 in interaction with host insect. These data indicate that Mcm1 is a crucial regulator of development, cell integrity, cell cycle and virulence in insect fungal pathogens.
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Affiliation(s)
- Xin Zhao
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Xingju Yang
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Zhuoyue Lu
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Huifang Wang
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Zhangjiang He
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Guangyan Zhou
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Zhibing Luo
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Yongjun Zhang
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
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11
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Lee YRJ, Liu B. Microtubule nucleation for the assembly of acentrosomal microtubule arrays in plant cells. THE NEW PHYTOLOGIST 2019; 222:1705-1718. [PMID: 30681146 DOI: 10.1111/nph.15705] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 01/07/2019] [Indexed: 05/15/2023]
Abstract
Contents Summary I. Introduction II. MT arrays in plant cells III. γ-Tubulin and MT nucleation IV. MT nucleation sites or flexible MTOCs in plant cells V. MT-dependent MT nucleation VI. Generating new MTs for spindle assembly VII. Generation of MTs for phragmoplast expansion during cytokinesis VIII. MT generation for the cortical MT array IX. MT nucleation: looking forward Acknowledgements References SUMMARY: Cytoskeletal microtubules (MTs) have a multitude of functions including intracellular distribution of molecules and organelles, cell morphogenesis, as well as segregation of the genetic material and separation of the cytoplasm during cell division among eukaryotic organisms. In response to internal and external cues, eukaryotic cells remodel their MT network in a regulated manner in order to assemble physiologically important arrays for cell growth, cell proliferation, or for cells to cope with biotic or abiotic stresses. Nucleation of new MTs is a critical step for MT remodeling. Although many key factors contributing to MT nucleation and organization are well conserved in different kingdoms, the centrosome, representing the most prominent microtubule organizing centers (MTOCs), disappeared during plant evolution as angiosperms lack the structure. Instead, flexible MTOCs may emerge on the plasma membrane, the nuclear envelope, and even organelles depending on types of cells and organisms and/or physiological conditions. MT-dependent MT nucleation is particularly noticeable in plant cells because it accounts for the primary source of MT generation for assembling spindle, phragmoplast, and cortical arrays when the γ-tubulin ring complex is anchored and activated by the augmin complex. It is intriguing what proteins are associated with plant-specific MTOCs and how plant cells activate or inactivate MT nucleation activities in spatiotemporally regulated manners.
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Affiliation(s)
- Yuh-Ru Julie Lee
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
| | - Bo Liu
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
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12
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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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13
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Jiang P, Zheng S, Lu L. Mitotic-Spindle Organizing Protein MztA Mediates Septation Signaling by Suppressing the Regulatory Subunit of Protein Phosphatase 2A-ParA in Aspergillus nidulans. Front Microbiol 2018; 9:988. [PMID: 29774021 PMCID: PMC5951981 DOI: 10.3389/fmicb.2018.00988] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 04/27/2018] [Indexed: 12/20/2022] Open
Abstract
The proper timing and positioning of cytokinesis/septation is crucial for hyphal growth and conidiation in Aspergillus nidulans. The septation initiation network (SIN) components are a conserved spindle pole body (SPB) localized signaling cascade and the terminal kinase complex SidB-MobA, which must localize on the SPB in this pathway to trigger septation/cytokinesis. The regulatory subunit of phosphatase PP2A-ParA has been identified to be a negative regulator capable of inactivating the SIN. However, little is known about how ParA regulates the SIN pathway and whether ParA regulates the septum formation process through affecting the SPB-localized SIN proteins. In this study, through RNA-Seq and genetic approaches, we identified a new positive septation regulator, a putative mitotic-spindle organizing protein and a yeast Mzt1 homolog MztA, which acts antagonistically toward PP2A-ParA to coordinately regulate the SPB-localized SIN proteins SidB-MobA during septation. These findings imply that regulators, phosphatase PP2A-ParA and MztA counteract the septation function probably through balancing the polymerization and depolymerization of microtubules at the SPB.
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Affiliation(s)
- Ping Jiang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Shujun Zheng
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Ling Lu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
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14
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Xiang X. Nuclear movement in fungi. Semin Cell Dev Biol 2017; 82:3-16. [PMID: 29241689 DOI: 10.1016/j.semcdb.2017.10.024] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 10/17/2017] [Accepted: 10/23/2017] [Indexed: 12/22/2022]
Abstract
Nuclear movement within a cell occurs in a variety of eukaryotic organisms including yeasts and filamentous fungi. Fungal molecular genetic studies identified the minus-end-directed microtubule motor cytoplasmic dynein as a critical protein for nuclear movement or orientation of the mitotic spindle contained in the nucleus. Studies in the budding yeast first indicated that dynein anchored at the cortex via its anchoring protein Num1 exerts pulling force on an astral microtubule to orient the anaphase spindle across the mother-daughter axis before nuclear division. Prior to anaphase, myosin V interacts with the plus end of an astral microtubule via Kar9-Bim1/EB1 and pulls the plus end along the actin cables to move the nucleus/spindle close to the bud neck. In addition, pushing or pulling forces generated from cortex-linked polymerization or depolymerization of microtubules drive nuclear movements in yeasts and possibly also in filamentous fungi. In filamentous fungi, multiple nuclei within a hyphal segment undergo dynein-dependent back-and-forth movements and their positioning is also influenced by cytoplasmic streaming toward the hyphal tip. In addition, nuclear movement occurs at various stages of fungal development and fungal infection of plant tissues. This review discusses our current understanding on the mechanisms of nuclear movement in fungal organisms, the importance of nuclear positioning and the regulatory strategies that ensure the proper positioning of nucleus/spindle.
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Affiliation(s)
- Xin Xiang
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences - F. Edward Hébert School of Medicine, Bethesda, MD, USA.
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15
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Zhang Y, Gao X, Manck R, Schmid M, Osmani AH, Osmani SA, Takeshita N, Fischer R. Microtubule-organizing centers of Aspergillus nidulans
are anchored at septa by a disordered protein. Mol Microbiol 2017; 106:285-303. [DOI: 10.1111/mmi.13763] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/03/2017] [Indexed: 01/21/2023]
Affiliation(s)
- Ying Zhang
- Department of Microbiology, Institute for Applied Biosciences; Karlsruhe Institute of Technology (KIT) - South Campus, Fritz-Haber-Weg 4; Karlsruhe D-76131 Germany
| | - Xiaolei Gao
- Department of Microbiology, Institute for Applied Biosciences; Karlsruhe Institute of Technology (KIT) - South Campus, Fritz-Haber-Weg 4; Karlsruhe D-76131 Germany
| | - Raphael Manck
- Department of Microbiology, Institute for Applied Biosciences; Karlsruhe Institute of Technology (KIT) - South Campus, Fritz-Haber-Weg 4; Karlsruhe D-76131 Germany
| | - Marjorie Schmid
- Department of Microbiology, Institute for Applied Biosciences; Karlsruhe Institute of Technology (KIT) - South Campus, Fritz-Haber-Weg 4; Karlsruhe D-76131 Germany
| | - Aysha H. Osmani
- Department of Molecular Genetics; Ohio State University, 105 Biological Sciences Building, 484 W 12th Ave; Columbus OH 43210 USA
| | - Stephen A. Osmani
- Department of Molecular Genetics; Ohio State University, 105 Biological Sciences Building, 484 W 12th Ave; Columbus OH 43210 USA
| | - Norio Takeshita
- Department of Microbiology, Institute for Applied Biosciences; Karlsruhe Institute of Technology (KIT) - South Campus, Fritz-Haber-Weg 4; Karlsruhe D-76131 Germany
- School of Life and Environmental Sciences; University of Tsukuba; Ten-Nou-Dai Tsukuba 305-8572 Japan
| | - Reinhard Fischer
- Department of Microbiology, Institute for Applied Biosciences; Karlsruhe Institute of Technology (KIT) - South Campus, Fritz-Haber-Weg 4; Karlsruhe D-76131 Germany
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16
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Salogiannis J, Reck-Peterson SL. Hitchhiking: A Non-Canonical Mode of Microtubule-Based Transport. Trends Cell Biol 2016; 27:141-150. [PMID: 27665063 DOI: 10.1016/j.tcb.2016.09.005] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 08/29/2016] [Accepted: 09/02/2016] [Indexed: 01/01/2023]
Abstract
The long-range movement of organelles, vesicles, and macromolecular complexes by microtubule-based transport is crucial for cell growth and survival. The canonical view of intracellular transport is that each cargo directly recruits molecular motors via cargo-specific adaptor molecules. Recently, a new paradigm called 'hitchhiking' has emerged: some cargos can achieve motility by interacting with other cargos that have already recruited molecular motors. In this way, cargos are co-transported together and their movements are directly coupled. Cargo hitchhiking was discovered in fungi. However, the observation that organelle dynamics are coupled in mammalian cells suggests that this paradigm may be evolutionarily conserved. We review here the data for hitchhiking and discuss the biological significance of this non-canonical mode of microtubule-based transport.
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Affiliation(s)
- John Salogiannis
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093, USA; Section of Cell and Developmental Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA; Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Samara L Reck-Peterson
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093, USA; Section of Cell and Developmental Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA; Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
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17
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Lyon AS, Morin G, Moritz M, Yabut KCB, Vojnar T, Zelter A, Muller E, Davis TN, Agard DA. Higher-order oligomerization of Spc110p drives γ-tubulin ring complex assembly. Mol Biol Cell 2016; 27:2245-58. [PMID: 27226487 PMCID: PMC4945142 DOI: 10.1091/mbc.e16-02-0072] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 05/19/2016] [Indexed: 02/01/2023] Open
Abstract
Assembly of the microtubule-nucleating γ-tubulin ring complex (γTuRC) requires higher-order oligomerization of Spc110p, which connects γTuRC to the yeast spindle pole body (SPB). Because Spc110p is highly concentrated at the SPB, spatial regulation of microtubule nucleation is thus achieved by exclusive assembly of γTuRCs proximal to the SPB. The microtubule (MT) cytoskeleton plays important roles in many cellular processes. In vivo, MT nucleation is controlled by the γ-tubulin ring complex (γTuRC), a 2.1-MDa complex composed of γ-tubulin small complex (γTuSC) subunits. The mechanisms underlying the assembly of γTuRC are largely unknown. In yeast, the conserved protein Spc110p both stimulates the assembly of the γTuRC and anchors the γTuRC to the spindle pole body. Using a quantitative in vitro FRET assay, we show that γTuRC assembly is critically dependent on the oligomerization state of Spc110p, with higher-order oligomers dramatically enhancing the stability of assembled γTuRCs. Our in vitro findings were confirmed with a novel in vivo γTuSC recruitment assay. We conclude that precise spatial control over MT nucleation is achieved by coupling localization and higher-order oligomerization of the receptor for γTuRC.
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Affiliation(s)
- Andrew S Lyon
- Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94158
| | - Geneviève Morin
- Department of Biochemistry, University of Washington, Seattle, WA 98195
| | - Michelle Moritz
- Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94158
| | | | - Tamira Vojnar
- Department of Biochemistry, University of Washington, Seattle, WA 98195
| | - Alex Zelter
- Department of Biochemistry, University of Washington, Seattle, WA 98195
| | - Eric Muller
- Department of Biochemistry, University of Washington, Seattle, WA 98195
| | - Trisha N Davis
- Department of Biochemistry, University of Washington, Seattle, WA 98195
| | - David A Agard
- Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94158
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18
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How peroxisomes partition between cells. A story of yeast, mammals and filamentous fungi. Curr Opin Cell Biol 2016; 41:73-80. [PMID: 27128775 DOI: 10.1016/j.ceb.2016.04.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 04/07/2016] [Accepted: 04/11/2016] [Indexed: 11/21/2022]
Abstract
Eukaryotic cells are subcompartmentalized into discrete, membrane-enclosed organelles. These organelles must be preserved in cells over many generations to maintain the selective advantages afforded by compartmentalization. Cells use complex molecular mechanisms of organelle inheritance to achieve high accuracy in the sharing of organelles between daughter cells. Here we focus on how a multi-copy organelle, the peroxisome, is partitioned in yeast, mammalian cells, and filamentous fungi, which differ in their mode of cell division. Cells achieve equidistribution of their peroxisomes through organelle transport and retention processes that act coordinately, although the strategies employed vary considerably by organism. Nevertheless, we propose that mechanisms common across species apply to the partitioning of all membrane-enclosed organelles.
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19
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Zhang Y, Teichert I, Kück U, Fischer R. Laser capture microdissection to identify septum-associated proteins in Aspergillus nidulans. Mycologia 2016; 108:528-32. [PMID: 26951366 DOI: 10.3852/15-218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 01/28/2016] [Indexed: 02/01/2023]
Abstract
To spatially resolve genetic differences at the cellular level, the laser-capture microdissection technique was developed. With this method cells can be cut from tissues with a laser beam and analyzed for DNA, RNA or protein composition. Here we adapted the technique to isolate septal microtubule-organizing center (MTOC)-associated proteins in Aspergillus nidulans About 3000 septa were collected and subjected to peptide fingerprinting by mass-spectrometric analysis. We identified the microtubule polymerase AlpA and found it interacts with ApsB specifically at sMTOCs, suggesting that AlpA might be involved in the assembly or the functioning of this protein complex.
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Affiliation(s)
- Ying Zhang
- Karlsruhe Institute of Technology (KIT) South Campus, Institute for Applied Biosciences Dept. of Microbiology, Hertzstrasse 16, D-76187 Karlsruhe, Germany
| | - Ines Teichert
- Ruhr Universität, Lehrstuhl für Allgemeine und Molekulare Botanik, Universitätsstraße 150, D-44780, Bochum, Germany
| | - Ulrich Kück
- Ruhr Universität, Lehrstuhl für Allgemeine und Molekulare Botanik, Universitätsstraße 150, D-44780, Bochum, Germany
| | - Reinhard Fischer
- Karlsruhe Institute of Technology (KIT) South Campus, Institute for Applied Biosciences Dept. of Microbiology, Hertzstrasse 16, D-76187 Karlsruhe, Germany
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20
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Egan MJ, McClintock MA, Hollyer IHL, Elliott HL, Reck-Peterson SL. Cytoplasmic dynein is required for the spatial organization of protein aggregates in filamentous fungi. Cell Rep 2016; 11:201-9. [PMID: 25865884 DOI: 10.1016/j.celrep.2015.03.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 02/10/2015] [Accepted: 03/11/2015] [Indexed: 01/01/2023] Open
Abstract
Eukaryotes have evolved multiple strategies for maintaining cellular protein homeostasis. One such mechanism involves neutralization of deleterious protein aggregates via their defined spatial segregation. Here, using the molecular disaggregase Hsp104 as a marker for protein aggregation, we describe the spatial and temporal dynamics of protein aggregates in the filamentous fungus Aspergillus nidulans. Filamentous fungi, such as A. nidulans, are a diverse group of species of major health and economic importance and also serve as model systems for studying highly polarized eukaryotic cells. We find that microtubules promote the formation of Hsp104-positive aggregates, which coalesce into discrete subcellular structures in a process dependent on the microtubule-based motor cytoplasmic dynein. Finally, we find that impaired clearance of these inclusions negatively impacts retrograde trafficking of endosomes, a conventional dynein cargo, indicating that microtubule-based transport can be overwhelmed by chronic cellular stress.
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21
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Gallmetzer A, Silvestrini L, Schinko T, Gesslbauer B, Hortschansky P, Dattenböck C, Muro-Pastor MI, Kungl A, Brakhage AA, Scazzocchio C, Strauss J. Reversible Oxidation of a Conserved Methionine in the Nuclear Export Sequence Determines Subcellular Distribution and Activity of the Fungal Nitrate Regulator NirA. PLoS Genet 2015; 11:e1005297. [PMID: 26132230 PMCID: PMC4488483 DOI: 10.1371/journal.pgen.1005297] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 05/25/2015] [Indexed: 01/02/2023] Open
Abstract
The assimilation of nitrate, a most important soil nitrogen source, is tightly regulated in microorganisms and plants. In Aspergillus nidulans, during the transcriptional activation process of nitrate assimilatory genes, the interaction between the pathway-specific transcription factor NirA and the exportin KapK/CRM1 is disrupted, and this leads to rapid nuclear accumulation and transcriptional activity of NirA. In this work by mass spectrometry, we found that in the absence of nitrate, when NirA is inactive and predominantly cytosolic, methionine 169 in the nuclear export sequence (NES) is oxidized to methionine sulfoxide (Metox169). This oxidation depends on FmoB, a flavin-containing monooxygenase which in vitro uses methionine and cysteine, but not glutathione, as oxidation substrates. The function of FmoB cannot be replaced by alternative Fmo proteins present in A. nidulans. Exposure of A. nidulans cells to nitrate led to rapid reduction of NirA-Metox169 to Met169; this reduction being independent from thioredoxin and classical methionine sulfoxide reductases. Replacement of Met169 by isoleucine, a sterically similar but not oxidizable residue, led to partial loss of NirA activity and insensitivity to FmoB-mediated nuclear export. In contrast, replacement of Met169 by alanine transformed the protein into a permanently nuclear and active transcription factor. Co-immunoprecipitation analysis of NirA-KapK interactions and subcellular localization studies of NirA mutants lacking different parts of the protein provided evidence that Met169 oxidation leads to a change in NirA conformation. Based on these results we propose that in the presence of nitrate the activation domain is exposed, but the NES is masked by a central portion of the protein (termed nitrate responsive domain, NiRD), thus restricting active NirA molecules to the nucleus. In the absence of nitrate, Met169 in the NES is oxidized by an FmoB-dependent process leading to loss of protection by the NiRD, NES exposure, and relocation of the inactive NirA to the cytosol.
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Affiliation(s)
- Andreas Gallmetzer
- Fungal Genetics and Genomics Unit, Department of Applied Genetics and Cell Biology, BOKU—University of Natural Resources and Life Science, Vienna, Vienna, Austria
| | - Lucia Silvestrini
- Fungal Genetics and Genomics Unit, Department of Applied Genetics and Cell Biology, BOKU—University of Natural Resources and Life Science, Vienna, Vienna, Austria
| | - Thorsten Schinko
- Fungal Genetics and Genomics Unit, Department of Applied Genetics and Cell Biology, BOKU—University of Natural Resources and Life Science, Vienna, Vienna, Austria
| | - Bernd Gesslbauer
- Institute of Pharmaceutical Sciences, Karl-Franzens-University Graz, Graz, Austria
| | - Peter Hortschansky
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoll Institute, Jena, Germany
- Department of Microbiology and Molecular Biology, Friedrich Schiller University Jena, Jena, Germany
| | - Christoph Dattenböck
- Fungal Genetics and Genomics Unit, Department of Applied Genetics and Cell Biology, BOKU—University of Natural Resources and Life Science, Vienna, Vienna, Austria
- Health and Environment Department, Austrian Institute of Technology GmbH—AIT, University and Research Center Tulln, Tulln an der Donau, Austria
| | | | - Andreas Kungl
- Institute of Pharmaceutical Sciences, Karl-Franzens-University Graz, Graz, Austria
| | - Axel A. Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoll Institute, Jena, Germany
- Department of Microbiology and Molecular Biology, Friedrich Schiller University Jena, Jena, Germany
| | - Claudio Scazzocchio
- Department of Microbiology, Imperial College, London, United Kingdom, and Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Orsay, France
| | - Joseph Strauss
- Fungal Genetics and Genomics Unit, Department of Applied Genetics and Cell Biology, BOKU—University of Natural Resources and Life Science, Vienna, Vienna, Austria
- Health and Environment Department, Austrian Institute of Technology GmbH—AIT, University and Research Center Tulln, Tulln an der Donau, Austria
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22
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Targeting of γ-tubulin complexes to microtubule organizing centers: conservation and divergence. Trends Cell Biol 2015; 25:296-307. [DOI: 10.1016/j.tcb.2014.12.002] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 11/25/2014] [Accepted: 12/01/2014] [Indexed: 11/29/2022]
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23
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Nakaoka Y, Kimura A, Tani T, Goshima G. Cytoplasmic nucleation and atypical branching nucleation generate endoplasmic microtubules in Physcomitrella patens. THE PLANT CELL 2015; 27:228-42. [PMID: 25616870 PMCID: PMC4330588 DOI: 10.1105/tpc.114.134817] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 12/28/2014] [Accepted: 01/08/2015] [Indexed: 05/19/2023]
Abstract
The mechanism underlying microtubule (MT) generation in plants has been primarily studied using the cortical MT array, in which fixed-angled branching nucleation and katanin-dependent MT severing predominate. However, little is known about MT generation in the endoplasm. Here, we explored the mechanism of endoplasmic MT generation in protonemal cells of Physcomitrella patens. We developed an assay that utilizes flow cell and oblique illumination fluorescence microscopy, which allowed visualization and quantification of individual MT dynamics. MT severing was infrequently observed, and disruption of katanin did not severely affect MT generation. Branching nucleation was observed, but it showed markedly variable branch angles and was occasionally accompanied by the transport of nucleated MTs. Cytoplasmic nucleation at seemingly random locations was most frequently observed and predominated when depolymerized MTs were regrown. The MT nucleator γ-tubulin was detected at the majority of the nucleation sites, at which a single MT was generated in random directions. When γ-tubulin was knocked down, MT generation was significantly delayed in the regrowth assay. However, nucleation occurred at a normal frequency in steady state, suggesting the presence of a γ-tubulin-independent backup mechanism. Thus, endoplasmic MTs in this cell type are generated in a less ordered manner, showing a broader spectrum of nucleation mechanisms in plants.
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Affiliation(s)
- Yuki Nakaoka
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan Marine Biological Laboratory, Woods Hole, Massachusetts 02543
| | - Akatsuki Kimura
- Marine Biological Laboratory, Woods Hole, Massachusetts 02543 National Institute of Genetics, Mishima 411-8540, Japan
| | - Tomomi Tani
- Marine Biological Laboratory, Woods Hole, Massachusetts 02543
| | - Gohta Goshima
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan Marine Biological Laboratory, Woods Hole, Massachusetts 02543
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24
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Pöhlmann J, Risse C, Seidel C, Pohlmann T, Jakopec V, Walla E, Ramrath P, Takeshita N, Baumann S, Feldbrügge M, Fischer R, Fleig U. The Vip1 inositol polyphosphate kinase family regulates polarized growth and modulates the microtubule cytoskeleton in fungi. PLoS Genet 2014; 10:e1004586. [PMID: 25254656 PMCID: PMC4177672 DOI: 10.1371/journal.pgen.1004586] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 07/08/2014] [Indexed: 11/19/2022] Open
Abstract
Microtubules (MTs) are pivotal for numerous eukaryotic processes ranging from cellular morphogenesis, chromosome segregation to intracellular transport. Execution of these tasks requires intricate regulation of MT dynamics. Here, we identify a new regulator of the Schizosaccharomyces pombe MT cytoskeleton: Asp1, a member of the highly conserved Vip1 inositol polyphosphate kinase family. Inositol pyrophosphates generated by Asp1 modulate MT dynamic parameters independent of the central +TIP EB1 and in a dose-dependent and cellular-context-dependent manner. Importantly, our analysis of the in vitro kinase activities of various S. pombe Asp1 variants demonstrated that the C-terminal phosphatase-like domain of the dual domain Vip1 protein negatively affects the inositol pyrophosphate output of the N-terminal kinase domain. These data suggest that the former domain has phosphatase activity. Remarkably, Vip1 regulation of the MT cytoskeleton is a conserved feature, as Vip1-like proteins of the filamentous ascomycete Aspergillus nidulans and the distantly related pathogenic basidiomycete Ustilago maydis also affect the MT cytoskeleton in these organisms. Consistent with the role of interphase MTs in growth zone selection/maintenance, all 3 fungal systems show aspects of aberrant cell morphogenesis. Thus, for the first time we have identified a conserved biological process for inositol pyrophosphates.
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Affiliation(s)
- Jennifer Pöhlmann
- Lehrstuhl für funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Carmen Risse
- Lehrstuhl für funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Constanze Seidel
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Karlsruhe, Germany
| | - Thomas Pohlmann
- Institut für Mikrobiologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Visnja Jakopec
- Lehrstuhl für funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Eva Walla
- Lehrstuhl für funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Pascal Ramrath
- Lehrstuhl für funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Norio Takeshita
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Karlsruhe, Germany
- University of Tsukuba, Faculty of Life and Environmental Sciences, Ibaraki, Tsukuba, Japan
| | - Sebastian Baumann
- Institut für Mikrobiologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Michael Feldbrügge
- Institut für Mikrobiologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Reinhard Fischer
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Karlsruhe, Germany
| | - Ursula Fleig
- Lehrstuhl für funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
- * E-mail:
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Improvement of Aspergillus nidulans penicillin production by targeting AcvA to peroxisomes. Metab Eng 2014; 25:131-9. [DOI: 10.1016/j.ymben.2014.07.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 07/03/2014] [Accepted: 07/09/2014] [Indexed: 11/21/2022]
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Lin TC, Neuner A, Schlosser YT, Scharf AND, Weber L, Schiebel E. Cell-cycle dependent phosphorylation of yeast pericentrin regulates γ-TuSC-mediated microtubule nucleation. eLife 2014; 3:e02208. [PMID: 24842996 PMCID: PMC4034690 DOI: 10.7554/elife.02208] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Budding yeast Spc110, a member of γ-tubulin complex receptor family (γ-TuCR), recruits γ-tubulin complexes to microtubule (MT) organizing centers (MTOCs). Biochemical studies suggest that Spc110 facilitates higher-order γ-tubulin complex assembly (Kollman et al., 2010). Nevertheless the molecular basis for this activity and the regulation are unclear. Here we show that Spc110 phosphorylated by Mps1 and Cdk1 activates γ-TuSC oligomerization and MT nucleation in a cell cycle dependent manner. Interaction between the N-terminus of the γ-TuSC subunit Spc98 and Spc110 is important for this activity. Besides the conserved CM1 motif in γ-TuCRs (Sawin et al., 2004), a second motif that we named Spc110/Pcp1 motif (SPM) is also important for MT nucleation. The activating Mps1 and Cdk1 sites lie between SPM and CM1 motifs. Most organisms have both SPM-CM1 (Spc110/Pcp1/PCNT) and CM1-only (Spc72/Mto1/Cnn/CDK5RAP2/myomegalin) types of γ-TuCRs. The two types of γ-TuCRs contain distinct but conserved C-terminal MTOC targeting domains. DOI:http://dx.doi.org/10.7554/eLife.02208.001 Microtubules are hollow structures made of proteins that have a central role in cell division and a variety of other important processes within cells. For a cell to divide successfully, the chromosomes containing the genetic information of the cell must be duplicated and then separated so that one copy of each chromosome ends up in each daughter cell. To separate the chromosomes, microtubules extend out from two structures called spindle pole bodies, which are found at either end of the cell, and pull one copy of each chromosome to opposite sides of the cell. Although the individual proteins that make up a microtubule can self-assemble into tubes, this occurs very slowly, so cells employ other molecules to speed up this process. In yeast cells, a protein called gamma-tubulin is recruited to the spindle pole body by the protein Spc110, where it combines with two other proteins to form a complex called the gamma-tubulin small complex. Several of these complexes then join together to form a ring, which probably acts as the platform that microtubules grow from. Recent observations suggested that Spc110 may help to construct this ring, but without revealing how. Now, Lin et al. reveal that Spc110 can regulate microtubule formation by controlling how several gamma-tubulin small complexes bind together, and have identified the exact section of Spc110 that interacts with the complexes. However, the Spc110 must become active before it can perform this role, and it is only activated during certain stages of cell division, through phosphorylation. The structures in Spc110 that bind to the gamma-tubulin small complex in yeast are also found in gamma-tubulin binding receptor proteins in human cells. The work of Lin et al. demonstrates that proteins that are assumed to have passive roles within cells, such as Spc110, often play more active roles instead. DOI:http://dx.doi.org/10.7554/eLife.02208.002
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Affiliation(s)
- Tien-Chen Lin
- Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany The Hartmut Hoffmann-Berling International Graduate School, University of Heidelberg, Heidelberg, Germany
| | - Annett Neuner
- Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
| | - Yvonne T Schlosser
- Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
| | - Annette N D Scharf
- Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
| | - Lisa Weber
- Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
| | - Elmar Schiebel
- Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Heidelberg, Germany
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Zheng Z, Gao T, Hou Y, Zhou M. Involvement of the anucleate primary sterigmata protein FgApsB in vegetative differentiation, asexual development, nuclear migration, and virulence in Fusarium graminearum. FEMS Microbiol Lett 2013; 349:88-98. [PMID: 24117691 DOI: 10.1111/1574-6968.12297] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 08/11/2013] [Accepted: 09/27/2013] [Indexed: 11/30/2022] Open
Abstract
The protein ApsB has been shown to play critical roles in the migration and positioning of nuclei and in the development of conidiophores in Aspergillus nidulans. The functions of ApsB in Fusarium graminearum, a causal agent of Fusarium head blight in China, are largely unknown. In this study, we used the blastp program at the Broad Institute to identify FgApsB, an F. graminearum homolog of A. nidulansApsB. The functions of FgApsB were evaluated by constructing a deletion mutant of FgApsB, designated ΔFgApsB-28. Conidiation and mycelial growth rate are reduced in ΔFgApsB-28. The hyphae of ΔFgApsB-28 are thinner than those of the wild type and have a different branching angle. ΔFgApsB-28 exhibited reduced aerial hyphae formation, but increased production of rubrofusarin. Whereas nuclei are evenly distributed in germ tubes and hyphae of the wild type, they are clustered and irregularly distributed in ΔFgApsB-28. The mutant exhibited increased resistance to cell wall-damaging agents, but reduced virulence on flowering wheat heads, which is consistent with its reduced production of the toxin deoxynivalenol. All of the defects in ΔFgApsB-28 were restored by genetic complementation with the parental FgApsB gene. Taken together, the results indicate that FgApsB is important for vegetative differentiation, asexual development, nuclear migration, and virulence in F. graminearum.
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Affiliation(s)
- Zhitian Zheng
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
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28
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Peraza-Reyes L, Berteaux-Lecellier V. Peroxisomes and sexual development in fungi. Front Physiol 2013; 4:244. [PMID: 24046747 PMCID: PMC3764329 DOI: 10.3389/fphys.2013.00244] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Accepted: 08/19/2013] [Indexed: 11/13/2022] Open
Abstract
Peroxisomes are versatile and dynamic organelles that are essential for the development of most eukaryotic organisms. In fungi, many developmental processes, such as sexual development, require the activity of peroxisomes. Sexual reproduction in fungi involves the formation of meiotic-derived sexual spores, often takes place inside multicellular fruiting bodies and requires precise coordination between the differentiation of multiple cell types and the progression of karyogamy and meiosis. Different peroxisomal functions contribute to the orchestration of this complex developmental process. Peroxisomes are required to sustain the formation of fruiting bodies and the maturation and germination of sexual spores. They facilitate the mobilization of reserve compounds via fatty acid β-oxidation and the glyoxylate cycle, allowing the generation of energy and biosynthetic precursors. Additionally, peroxisomes are implicated in the progression of meiotic development. During meiotic development in Podospora anserina, there is a precise modulation of peroxisome assembly and dynamics. This modulation includes changes in peroxisome size, number and localization, and involves a differential activity of the protein-machinery that drives the import of proteins into peroxisomes. Furthermore, karyogamy, entry into meiosis and sorting of meiotic-derived nuclei into sexual spores all require the activity of peroxisomes. These processes rely on different peroxisomal functions and likely depend on different pathways for peroxisome assembly. Indeed, emerging studies support the existence of distinct import channels for peroxisomal proteins that contribute to different developmental stages.
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Affiliation(s)
- Leonardo Peraza-Reyes
- CNRS, Institut de Génétique et Microbiologie, University Paris-Sud, UMR8621 Orsay, France
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Maruyama JI, Kitamoto K. Expanding functional repertoires of fungal peroxisomes: contribution to growth and survival processes. Front Physiol 2013; 4:177. [PMID: 23882222 PMCID: PMC3713238 DOI: 10.3389/fphys.2013.00177] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 06/23/2013] [Indexed: 11/14/2022] Open
Abstract
It has long been regarded that the primary function of fungal peroxisomes is limited to the β-oxidation of fatty acids, as mutants lacking peroxisomal function fail to grow in minimal medium containing fatty acids as the sole carbon source. However, studies in filamentous fungi have revealed that peroxisomes have diverse functional repertoires. This review describes the essential roles of peroxisomes in the growth and survival processes of filamentous fungi. One such survival mechanism involves the Woronin body, a Pezizomycotina-specific organelle that plugs the septal pore upon hyphal lysis to prevent excessive cytoplasmic loss. A number of reports have demonstrated that Woronin bodies are derived from peroxisomes. Specifically, the Woronin body protein Hex1 is targeted to peroxisomes by peroxisomal targeting sequence 1 (PTS1) and forms a self-assembled structure that buds from peroxisomes to form the Woronin body. Peroxisomal deficiency reduces the ability of filamentous fungi to prevent excessive cytoplasmic loss upon hyphal lysis, indicating that peroxisomes contribute to the survival of these multicellular organisms. Peroxisomes were also recently found to play a vital role in the biosynthesis of biotin, which is an essential cofactor for various carboxylation and decarboxylation reactions. In biotin-prototrophic fungi, peroxisome-deficient mutants exhibit growth defects when grown on glucose as a carbon source due to biotin auxotrophy. The biotin biosynthetic enzyme BioF (7-keto-8-aminopelargonic acid synthase) contains a PTS1 motif that is required for both peroxisomal targeting and biotin biosynthesis. In plants, the BioF protein contains a conserved PTS1 motif and is also localized in peroxisomes. These findings indicate that the involvement of peroxisomes in biotin biosynthesis is evolutionarily conserved between fungi and plants, and that peroxisomes play a key role in fungal growth.
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Roubin R, Acquaviva C, Chevrier V, Sedjaï F, Zyss D, Birnbaum D, Rosnet O. Myomegalin is necessary for the formation of centrosomal and Golgi-derived microtubules. Biol Open 2012; 2:238-50. [PMID: 23430395 PMCID: PMC3575658 DOI: 10.1242/bio.20123392] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 11/21/2012] [Indexed: 11/20/2022] Open
Abstract
The generation of cellular microtubules is initiated at specific sites such as the centrosome and the Golgi apparatus that contain nucleation complexes rich in γ-tubulin. The microtubule growing plus-ends are stabilized by plus-end tracking proteins (+TIPs), mainly EB1 and associated proteins. Myomegalin was identified as a centrosome/Golgi protein associated with cyclic nucleotide phosphodiesterase. We show here that Myomegalin exists as several isoforms. We characterize two of them. One isoform, CM-MMG, harbors a conserved domain (CM1), recently described as a nucleation activator, and is related to a family of γ-tubulin binding proteins, which includes Drosophila centrosomin. It localizes at the centrosome and at the cis-Golgi in an AKAP450-dependent manner. It recruits γ-tubulin nucleating complexes and promotes microtubule nucleation. The second isoform, EB-MMG, is devoid of CM1 domain and has a unique N-terminus with potential EB1-binding sites. It localizes at the cis-Golgi and can localize to microtubule plus-ends. EB-MMG binds EB1 and affects its loading on microtubules and microtubule growth. Depletion of Myomegalin by small interfering RNA delays microtubule growth from the centrosome and Golgi apparatus, and decreases directional migration of RPE1 cells. In conclusion, the Myomegalin gene encodes different isoforms that regulate microtubules. At least two of these have different roles, demonstrating a previously unknown mechanism to control microtubules in vertebrate cells.
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Affiliation(s)
- Régine Roubin
- Centre de Recherche en Cancérologie de Marseille , INSERM UMR1068, F-13009 Marseille , France ; Institut Paoli-Calmettes , F-13009 Marseille , France ; CNRS U7258, F-13009 Marseille , France ; Aix-Marseille Université , F-13007 Marseille , France
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Jedd G, Pieuchot L. Multiple modes for gatekeeping at fungal cell-to-cell channels. Mol Microbiol 2012; 86:1291-4. [PMID: 23127137 DOI: 10.1111/mmi.12074] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2012] [Indexed: 12/23/2022]
Abstract
Cell-to-cell channels appear to be indispensable for successful multicellular organization and arose independently in animals, plants and fungi. Most of the fungi obtain nutrients from the environment by growing in an exploratory and invasive manner, and this ability depends on multicellular filaments known as hyphae. These cells grow by tip extension and can be divided into compartments by cell walls that typically retain a central pore that allows intercellular transport and cooperation. In the major clade of filamentous Ascomycota, integrity of this coenocytic organization is maintained by Woronin body organelles, which function as emergency patches of septal pores. In this issue of Molecular Microbiology, Bleichrodt and co-workers show that Woronin bodies can also form tight reversible associations with the pore and further link this to variation in levels of compartmental gene expression. These data define an additional modality of Woronin body-dependent gatekeeping. This commentary focuses on the implications of this work and the potential role of different modes of pore gating in controlling the growth and development of fungal tissues.
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Affiliation(s)
- Gregory Jedd
- Temasek Life Sciences Laboratory and Department of Biological Sciences, National University of Singapore, Singapore.
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Egan MJ, McClintock MA, Reck-Peterson SL. Microtubule-based transport in filamentous fungi. Curr Opin Microbiol 2012; 15:637-45. [PMID: 23127389 DOI: 10.1016/j.mib.2012.10.003] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 10/04/2012] [Accepted: 10/07/2012] [Indexed: 01/29/2023]
Abstract
Defects in microtubule-based transport are implicated in many neuropathologies. The filamentous fungi Aspergillus nidulans and Ustilago maydis are valuable models for studying transport owing to their yeast-like genetic and biochemical tractability and metazoan-like dependence on microtubule-based transport for cellular trafficking. In these organisms the role of microtubules in nuclear positioning is well studied, but recent work has expanded the range of cargos to include endosomes, messenger RNA, secretory vesicles, peroxisomes, and nuclear pore complexes, reflecting the diversity of metazoan systems. Furthermore, similarities in transport mechanisms exist between filamentous fungi and metazoan neurons, demonstrating the suitability of A. nidulans and U. maydis for studying the molecular basis of transport-related neuropathologies such as lissencephaly, motor neuron disease, and Perry syndrome.
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Affiliation(s)
- Martin J Egan
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, United States
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Evidence that two Pcl-like cyclins control Cdk9 activity during cell differentiation in Aspergillus nidulans asexual development. EUKARYOTIC CELL 2012; 12:23-36. [PMID: 23104571 DOI: 10.1128/ec.00181-12] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cyclin-dependent protein kinases (CDKs) are usually involved in cell cycle regulation. However, Cdk9 is an exception and promotes RNA synthesis through phosphorylation of the carboxy-terminal domain (CTD) of the largest subunit of RNA polymerase II (RNAPII). The CTD is comprised of repeating heptapeptides, in which serine residues at positions 2, 5, and 7 are of crucial importance. Ser5 phosphorylation causes transcription initiation and promoter escape. However, RNAPII pauses 20 to 50 bp downstream from the transcription start site, until Cdk9 phosphorylates Ser2. This event relieves the checkpoint and promotes the processivity of elongation. Here we present evidence that in the filamentous fungus Aspergillus nidulans, a Cdk9 homologue, PtkA, serves specific functions in conidiophore development. It was previously shown that PtkA interacts with two cyclins, PclA and the T cyclin PchA. Using yeast two-hybrid screens, we identified a third cyclin, PclB, and a kinase, PipA(Bud32). Both proteins were expressed in hyphae and in conidiophores, but interaction between each protein and PtkA was restricted to the conidiophores. Deletion of pchA caused a severe growth defect, and deletion of pipA was lethal, suggesting basic functions in PtkA-dependent gene transcription. In contrast, deletion of pclB in combination with deletion of pclA essentially caused a block in spore formation. We present evidence that the phosphorylation status of the CTD of RNA polymerase II in the conidiophore changes upon deletion of pclA or pclB. Our results suggest that tissue-specific modulation of Cdk9 activity by PclA and PclB is required for proper differentiation.
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A pericentrin-related protein homolog in Aspergillus nidulans plays important roles in nucleus positioning and cell polarity by affecting microtubule organization. EUKARYOTIC CELL 2012; 11:1520-30. [PMID: 23087372 DOI: 10.1128/ec.00203-12] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Pericentrin is a large coiled-coil protein in mammalian centrosomes that serves as a multifunctional scaffold for anchoring numerous proteins. Recent studies have linked numerous human disorders with mutated or elevated levels of pericentrin, suggesting unrecognized contributions of pericentrin-related proteins to the development of these disorders. In this study, we characterized AnPcpA, a putative homolog of pericentrin-related protein in the model filamentous fungus Aspergillus nidulans, and found that it is essential for conidial germination and hyphal development. Compared to the hyphal apex localization pattern of calmodulin (CaM), which has been identified as an interactive partner of the pericentrin homolog, GFP-AnPcpA fluorescence dots are associated mainly with nuclei, while the accumulation of CaM at the hyphal apex depends on the function of AnPcpA. In addition, the depletion of AnPcpA by an inducible alcA promoter repression results in severe growth defects and abnormal nuclear segregation. Most interestingly, in mature hyphal cells, knockdown of pericentrin was able to significantly induce changes in cell shape and cytoskeletal remodeling; it resulted in some enlarged compartments with condensed nuclei and anucleate small compartments as well. Moreover, defects in AnPcpA significantly disrupted the microtubule organization and nucleation, suggesting that AnPcpA may affect nucleus positioning by influencing microtubule organization.
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Pieuchot L, Jedd G. Peroxisome Assembly and Functional Diversity in Eukaryotic Microorganisms. Annu Rev Microbiol 2012; 66:237-63. [DOI: 10.1146/annurev-micro-092611-150126] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Laurent Pieuchot
- Temasek Life Sciences Laboratory and Department of Biological Sciences, National University of Singapore, 117604 Singapore; ,
| | - Gregory Jedd
- Temasek Life Sciences Laboratory and Department of Biological Sciences, National University of Singapore, 117604 Singapore; ,
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Zhang J, Tan K, Wu X, Chen G, Sun J, Reck-Peterson SL, Hammer JA, Xiang X. Aspergillus myosin-V supports polarized growth in the absence of microtubule-based transport. PLoS One 2011; 6:e28575. [PMID: 22194856 PMCID: PMC3237463 DOI: 10.1371/journal.pone.0028575] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Accepted: 11/10/2011] [Indexed: 12/23/2022] Open
Abstract
In the filamentous fungus Aspergillus nidulans, both microtubules and actin filaments are important for polarized growth at the hyphal tip. Less clear is how different microtubule-based and actin-based motors work together to support this growth. Here we examined the role of myosin-V (MYOV) in hyphal growth. MYOV-depleted cells form elongated hyphae, but the rate of hyphal elongation is significantly reduced. In addition, although wild type cells without microtubules still undergo polarized growth, microtubule disassembly abolishes polarized growth in MYOV-depleted cells. Thus, MYOV is essential for polarized growth in the absence of microtubules. Moreover, while a triple kinesin null mutant lacking kinesin-1 (KINA) and two kinesin-3s (UNCA and UNCB) undergoes hyphal elongation and forms a colony, depleting MYOV in this triple mutant results in lethality due to a severe defect in polarized growth. These results argue that MYOV, through its ability to transport secretory cargo, can support a significant amount of polarized hyphal tip growth in the absence of any microtubule-based transport. Finally, our genetic analyses also indicate that KINA (kinesin-1) rather than UNCA (kinesin-3) is the major kinesin motor that supports polarized growth in the absence of MYOV.
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Affiliation(s)
- Jun Zhang
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, F. Edward Hébert School of Medicine, Bethesda, Maryland, United States of America
| | - Kaeling Tan
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Xufeng Wu
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Guifang Chen
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, F. Edward Hébert School of Medicine, Bethesda, Maryland, United States of America
| | - Jinjin Sun
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- River Hill High School, Clarksville, Maryland, United States of America
| | - Samara L. Reck-Peterson
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - John A. Hammer
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail: (JH); (XX)
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, F. Edward Hébert School of Medicine, Bethesda, Maryland, United States of America
- * E-mail: (JH); (XX)
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Peraza-Reyes L, Arnaise S, Zickler D, Coppin E, Debuchy R, Berteaux-Lecellier V. The importomer peroxins are differentially required for peroxisome assembly and meiotic development in Podospora anserina: insights into a new peroxisome import pathway. Mol Microbiol 2011; 82:365-77. [PMID: 21895788 DOI: 10.1111/j.1365-2958.2011.07816.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Peroxisome biogenesis relies on two known peroxisome matrix protein import pathways that are mediated by the receptors PEX5 and PEX7. These pathways converge at the importomer, a peroxisome-membrane complex that is required for protein translocation into peroxisomes and consists of docking and RING-finger subcomplexes. In the fungus Podospora anserina, the RING-finger peroxins are crucial for meiocyte formation, while PEX5, PEX7 or the docking peroxin PEX14 are not. Here we show that PEX14 and the PEX14-related protein PEX14/17 are differentially involved in peroxisome import during development. PEX14/17 activity does not compensate for loss of PEX14 function, and elimination of both proteins has no effect on meiocyte differentiation. In contrast, the docking peroxin PEX13, and the peroxins implicated in peroxisome membrane biogenesis PEX3 and PEX19, are required for meiocyte formation. Remarkably, the PTS2 coreceptor PEX20 is also essential for meiocyte differentiation and this function does not require PEX5 or PEX7. This finding suggests that PEX20 can mediate the import receptor activity of specific peroxisome matrix proteins. Our results suggest a new pathway for peroxisome import, which relies on PEX20 as import receptor and which seems critically required for specific developmental processes, like meiocyte differentiation in P. anserina.
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Affiliation(s)
- Leonardo Peraza-Reyes
- Institut de Génétique et Microbiologie, Univ. Paris-Sud, UMR8621, F-91405 Orsay, France.
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38
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Bartoszewska M, Opaliński L, Veenhuis M, van der Klei IJ. The significance of peroxisomes in secondary metabolite biosynthesis in filamentous fungi. Biotechnol Lett 2011; 33:1921-31. [PMID: 21660569 PMCID: PMC3173629 DOI: 10.1007/s10529-011-0664-y] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 05/24/2011] [Indexed: 01/08/2023]
Abstract
Peroxisomes are ubiquitous organelles characterized by a protein-rich matrix surrounded by a single membrane. In filamentous fungi, peroxisomes are crucial for the primary metabolism of several unusual carbon sources used for growth (e.g. fatty acids), but increasing evidence is presented that emphasize the crucial role of these organelles in the formation of a variety of secondary metabolites. In filamentous fungi, peroxisomes also play a role in development and differentiation whereas specialized peroxisomes, the Woronin bodies, play a structural role in plugging septal pores. The biogenesis of peroxisomes in filamentous fungi involves the function of conserved PEX genes, as well as genes that are unique for these organisms. Peroxisomes are also subject to autophagic degradation, a process that involves ATG genes. The interplay between organelle biogenesis and degradation may serve a quality control function, thereby allowing a continuous rejuvenation of the organelle population in the cells.
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Affiliation(s)
- Magdalena Bartoszewska
- Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Kluyver Centre for Genomics of Industrial Fermentation, P.O. Box 11103, 9700 CC Groningen, The Netherlands
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Lichius A, Berepiki A, Read ND. Form follows function – The versatile fungal cytoskeleton. Fungal Biol 2011; 115:518-40. [DOI: 10.1016/j.funbio.2011.02.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 02/15/2011] [Accepted: 02/17/2011] [Indexed: 12/11/2022]
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On the role of microtubules, cell end markers, and septal microtubule organizing centres on site selection for polar growth in Aspergillus nidulans. Fungal Biol 2011; 115:506-17. [PMID: 21640315 DOI: 10.1016/j.funbio.2011.02.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Revised: 02/04/2011] [Accepted: 02/09/2011] [Indexed: 02/01/2023]
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Architecture and development of the Neurospora crassa hypha – a model cell for polarized growth. Fungal Biol 2011; 115:446-74. [PMID: 21640311 DOI: 10.1016/j.funbio.2011.02.008] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Revised: 02/08/2011] [Accepted: 02/09/2011] [Indexed: 11/20/2022]
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Differential localization patterns of septins during growth of the human fungal pathogen Aspergillus fumigatus reveal novel functions. Biochem Biophys Res Commun 2011; 405:238-43. [PMID: 21219860 DOI: 10.1016/j.bbrc.2011.01.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 01/05/2011] [Indexed: 11/20/2022]
Abstract
Septins, a conserved family of GTPases, are heteropolymeric filament-forming proteins that associate with the cell membrane and cytoskeleton and serve essential functions in cell division and morphogenesis. Their roles in fungal cell wall chitin deposition, septation, cytokinesis, and sporulation have been well established and they have recently been implicated in tissue invasion and virulence in Candida albicans. Septins have never been investigated in the human pathogenic fungus, Aspergillus fumigatus, which is a leading cause of death in immunocompromised patients. Here we localize all the five septins (AspA-E) from A. fumigatus for the first time, and show that each of the five septins exhibit varied patterns of distribution. Interestingly AspE, which is unique to filamentous fungi, and AspD, belonging to the CDC10 class of septins, localized prominently to tubular structures which were dependent on actin and microtubule networks. Localization of AspD and AspE has never been reported in filamentous fungi. Taken together these results suggest that septins in A. fumigatus might have unique functions in morphogenesis and pathogenicity.
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Jedd G. Fungal evo-devo: organelles and multicellular complexity. Trends Cell Biol 2010; 21:12-9. [PMID: 20888233 DOI: 10.1016/j.tcb.2010.09.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Revised: 08/31/2010] [Accepted: 09/01/2010] [Indexed: 10/19/2022]
Abstract
Peroxisome-derived Woronin bodies of the Ascomycota phyla, and the endoplasmic reticulum (ER)-derived septal pore cap (SPC) of the Basidiomycota, are both fungal organelles that prevent cytoplasmic bleeding when multicellular hyphal filaments are wounded. Analysis of Woronin body constituent proteins suggests that these organelles evolved in part through gene duplication and co-opting of non-essential genes for new functions, indicating that new organelles can arise through typical evolutionary mechanisms. Interestingly, clades possessing the Woronin body and SPC also produce the largest and most complex multicellular fungal reproductive structures. Certain Woronin body and SPC mutants have defects in growth and development, suggesting functions beyond cellular wound healing. I argue that studying these specialized systems will help to reveal the basis for fungal diversity and provide general principles for co-evolution of organelles and multicellular complexity.
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Affiliation(s)
- Gregory Jedd
- Temasek Life Sciences Laboratory and Department of Biological Sciences, The National University of Singapore, Singapore 117604.
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Seiler S, Justa-Schuch D. Conserved components, but distinct mechanisms for the placement and assembly of the cell division machinery in unicellular and filamentous ascomycetes. Mol Microbiol 2010; 78:1058-76. [PMID: 21091496 DOI: 10.1111/j.1365-2958.2010.07392.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cytokinesis is essential for cell proliferation, yet its molecular description is challenging, because >100 conserved proteins must be spatially and temporally co-ordinated. Despite the high importance of a tight co-ordination of cytokinesis with chromosome and organelle segregation, the mechanism for determining the cell division plane is one of the least conserved aspects of cytokinesis in eukaryotic cells. Budding and fission yeast have developed fundamentally distinct mechanisms to ensure proper nuclear segregation. The extent to which these pathways are conserved in multicellular fungi remains unknown. Recent progress indicates common components, but different mechanisms that are required for proper selection of the septation site in the different groups of Ascomycota. Cortical cues are used in yeast- and filament-forming species of the Saccharomycotina clade that are established at the incipient bud site or the hyphal tip respectively. In contrast, septum formation in the filament-forming Pezizomycotina species Aspergillus nidulans and Neurospora crassa seems more closely related to the fission yeast programme in that they may combine mitotic signals with a cell end-based marker system and Rho GTPase signalling. Thus, significant differences in the use and connection of conserved signalling modules become apparent that reflect the phylogenetic relationship of the analysed models.
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Affiliation(s)
- Stephan Seiler
- Institut für Mikrobiologie und Genetik, Universität Göttingen, Grisebachstr. 8, D-37077 Göttingen, Germany.
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