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Chen X, Moran Torres JP, Jan Vonk P, Damen JMA, Reiding KR, Dijksterhuis J, Lugones LG, Wösten HAB. The pleiotropic phenotype of FlbA of Aspergillus niger is explained in part by the activity of seven of its downstream-regulated transcription factors. Fungal Genet Biol 2024; 172:103894. [PMID: 38657897 DOI: 10.1016/j.fgb.2024.103894] [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: 03/03/2024] [Revised: 04/03/2024] [Accepted: 04/22/2024] [Indexed: 04/26/2024]
Abstract
Inactivation of flbA in Aspergillus niger results in thinner cell walls, increased cell lysis, abolished sporulation, and an increased secretome complexity. A total of 36 transcription factor (TF) genes are differentially expressed in ΔflbA. Here, seven of these genes (abaA, aslA, aslB, azf1, htfA, nosA, and srbA) were inactivated. Inactivation of each of these genes affected sporulation and, with the exception of abaA, cell wall integrity and protein secretion. The impact on secretion was strongest in the case of ΔaslA and ΔaslB that showed increased pepsin, cellulase, and amylase activity. Biomass was reduced of agar cultures of ΔabaA, ΔaslA, ΔnosA, and ΔsrbA, while biomass was higher in liquid shaken cultures of ΔaslA and ΔaslB. The ΔaslA and ΔhtfA strains showed increased resistance to H2O2, while ΔaslB was more sensitive to this reactive oxygen species. Together, inactivation of the seven TF genes impacted biomass formation, sporulation, protein secretion, and stress resistance, and thereby these genes explain at least part of the pleiotropic phenotype of ΔflbA of A. niger.
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Affiliation(s)
- Xiaoyi Chen
- Microbiology, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
| | - Juan P Moran Torres
- Microbiology, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
| | - Peter Jan Vonk
- Microbiology, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
| | - J Mirjam A Damen
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
| | - Karli R Reiding
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
| | - Jan Dijksterhuis
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands.
| | - Luis G Lugones
- Microbiology, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
| | - Han A B Wösten
- Microbiology, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
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2
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Rogers AM, Egan MJ. Septum-associated microtubule organizing centers within conidia support infectious development by the blast fungus Magnaporthe oryzae. Fungal Genet Biol 2023; 165:103768. [PMID: 36596442 DOI: 10.1016/j.fgb.2022.103768] [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: 09/19/2022] [Revised: 12/16/2022] [Accepted: 12/22/2022] [Indexed: 01/01/2023]
Abstract
Cytoplasmic microtubule arrays play important and diverse roles within fungal cells, including serving as molecular highways for motor-driven organelle motility. While the dynamic plus ends of cytoplasmic microtubules are free to explore the cytoplasm through their stochastic growth and shrinkage, their minus ends are nucleated at discrete organizing centers, composed of large multi-subunit protein complexes. The location and composition of these microtubule organizing centers varies depending on genus, cell type, and in some instances cell-cycle stage. Despite their obvious importance, our understanding of the nature, diversity, and regulation of microtubule organizing centers in fungi remains incomplete. Here, using three-color fluorescence microscopy based live-cell imaging, we investigate the organization and dynamic behavior of the microtubule cytoskeleton within infection-related cell types of the filamentous fungus,Magnaporthe oryzae, a highly destructive pathogen of rice and wheat. We provide data to support the idea that cytoplasmic microtubules are nucleated at septa, rather than at nuclear spindle pole bodies, within the three-celled blast conidium, and provide new insight into remodeling of the microtubule cytoskeleton during nuclear division and inheritance. Lastly, we provide a more complete picture of the architecture and subcellular organization of the prototypical blast appressorium, a specialized pressure-generating cell type used to invade host tissue. Taken together, our study provides new insight into microtubule nucleation, organization, and dynamics in specialized and differentiated fungal cell types.
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Affiliation(s)
- Audra Mae Rogers
- Department of Entomology and Plant Pathology, University of Arkansas, Fayetteville, AR 72701, USA
| | - Martin John Egan
- Department of Entomology and Plant Pathology, University of Arkansas, Fayetteville, AR 72701, USA.
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3
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Rajasenan S, Osmani AH, Osmani SA. Modulation of sensitivity to gaseous signaling by sterol-regulatory hypoxic transcription factors in Aspergillus nidulans biofilm cells. Fungal Genet Biol 2022; 163:103739. [PMID: 36089227 DOI: 10.1016/j.fgb.2022.103739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 08/15/2022] [Accepted: 09/05/2022] [Indexed: 01/06/2023]
Abstract
Fungal biofilm founder cells experience self-generated hypoxia leading to dramatic changes in their cell biology. For example, during Aspergillus nidulans biofilm formation microtubule (MT) disassembly is triggered causing dispersal of EB1 from MT tips. This process is dependent on SrbA, a sterol regulatory element-binding transcription factor required for adaptation to hypoxia. We show that SrbA, an ER resident protein prior to activation, is proteolytically activated during early stages of biofilm formation and that, like SrbA itself, its activating proteases are also required for normal biofilm MT disassembly. In addition to SrbA, the AtrR transcription factor is also found to be required to modulate cellular responses to gaseous signaling during biofilm development. Using co-cultures, we further show that cells lacking srbA or atrR are capable of responding to biofilm generated gaseous microenvironments but are actually more sensitive to this signal than wild type cells. SrbA is a regulator of ergosterol biosynthetic genes and we find that the levels of seven GFP-tagged Erg proteins differentially accumulate during biofilm formation with various dependencies on SrbA for their accumulation. This uncovers a complex pattern of regulation with biofilm accumulation of only some Erg proteins being dependent on SrbA with others accumulating to higher levels in its absence. Because different membrane sterols are known to influence cell permeability to gaseous molecules, including oxygen, we propose that differential regulation of ergosterol biosynthetic proteins by SrbA potentially calibrates the cell's responsiveness to gaseous signaling which in turn modifies the cell biology of developing biofilm cells.
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Affiliation(s)
- Shobhana Rajasenan
- Ohio State University, Department of Molecular Genetics, 105 Biological Sciences Building, 484 West 12th Avenue, Columbus, OH 43210, United States
| | - Aysha H Osmani
- Ohio State University, Department of Molecular Genetics, 105 Biological Sciences Building, 484 West 12th Avenue, Columbus, OH 43210, United States
| | - Stephen A Osmani
- Ohio State University, Department of Molecular Genetics, 105 Biological Sciences Building, 484 West 12th Avenue, Columbus, OH 43210, United States.
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4
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Macabrey D, Longchamp A, MacArthur MR, Lambelet M, Urfer S, Deglise S, Allagnat F. Sodium thiosulfate acts as a hydrogen sulfide mimetic to prevent intimal hyperplasia via inhibition of tubulin polymerisation. EBioMedicine 2022; 78:103954. [PMID: 35334307 PMCID: PMC8941337 DOI: 10.1016/j.ebiom.2022.103954] [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: 08/09/2021] [Revised: 03/08/2022] [Accepted: 03/08/2022] [Indexed: 11/06/2022] Open
Abstract
Background Intimal hyperplasia (IH) remains a major limitation in the long-term success of any type of revascularisation. IH is due to vascular smooth muscle cell (VSMC) dedifferentiation, proliferation and migration. The gasotransmitter Hydrogen Sulfide (H2S), mainly produced in blood vessels by the enzyme cystathionine- γ-lyase (CSE), inhibits IH in pre-clinical models. However, there is currently no H2S donor available to treat patients. Here we used sodium thiosulfate (STS), a clinically-approved source of sulfur, to limit IH. Methods Low density lipoprotein receptor deleted (LDLR−/−), WT or Cse-deleted (Cse−/−) male mice randomly treated with 4 g/L STS in the water bottle were submitted to focal carotid artery stenosis to induce IH. Human vein segments were maintained in culture for 7 days to induce IH. Further in vitro studies were conducted in primary human vascular smooth muscle cells (VSMCs). Findings STS inhibited IH in WT mice, as well as in LDLR−/− and Cse−/− mice, and in human vein segments. STS inhibited cell proliferation in the carotid artery wall and in human vein segments. STS increased polysulfides in vivo and protein persulfidation in vitro, which correlated with microtubule depolymerisation, cell cycle arrest and reduced VSMC migration and proliferation. Interpretation STS, a drug used for the treatment of cyanide poisoning and calciphylaxis, protects against IH in a mouse model of arterial restenosis and in human vein segments. STS acts as an H2S donor to limit VSMC migration and proliferation via microtubule depolymerisation. Funding This work was supported by the Swiss National Science Foundation (grant FN-310030_176158 to FA and SD and PZ00P3-185927 to AL); the Novartis Foundation to FA; and the Union des Sociétés Suisses des Maladies Vasculaires to SD, and the Fondation pour la recherche en chirurgie vasculaire et thoracique.
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Corrêa-Almeida C, Borba-Santos LP, Rollin-Pinheiro R, Barreto-Bergter E, Rozental S, Kurtenbach E. Characterization of Aspergillus nidulans Biofilm Formation and Structure and Their Inhibition by Pea Defensin Psd2. Front Mol Biosci 2022; 9:795255. [PMID: 35155575 PMCID: PMC8830917 DOI: 10.3389/fmolb.2022.795255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 01/11/2022] [Indexed: 11/13/2022] Open
Abstract
Approximately four million people contract fungal infections every year in Brazil, primarily caused by Aspergillus spp. The ability of these fungi to form biofilms in tissues and medical devices complicates treatment and contributes to high rates of morbidity and mortality in immunocompromised patients. Psd2 is a pea defensin of 5.4 kDa that possesses good antifungal activity against planktonic cells of representative pathogenic fungi. Its function depends on interactions with membrane and cell wall lipid components such as glucosylceramide and ergosterol. In the present study, we characterized Aspergillus nidulans biofilm formation and determined the effect of Psd2 on A. nidulans biofilms. After 4 hours, A. nidulans conidia adhered to polystyrene surfaces and formed a robust extracellular matrix-producing biofilm at 24 h, increasing thickness until 48 h Psd2 inhibited A. nidulans biofilm formation in a dose-dependent manner. Most notably, at 10 μM Psd2 inhibited 50% of biofilm viability and biomass and 40% of extracellular matrix production. Psd2 significantly decreased the colonized surface area by the biofilm and changed its level of organization, causing a shortening of length and diameter of hyphae and inhibition of conidiophore formation. This activity against A. nidulans biofilm suggests a potential use of Psd2 as a prototype to design new antifungal agents to prevent biofilm formation by A. nidulans and related species.
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Affiliation(s)
- Caroline Corrêa-Almeida
- Laboratório de Biologia Molecular e Bioquímica de Proteínas, Programa de Biologia Molecular e Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brasil
| | - Luana P. Borba-Santos
- Laboratório de Biologia Celular de Fungos, Programa de Parasitologia e Biologia Celular, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brasil
| | - Rodrigo Rollin-Pinheiro
- Laboratório de Química Biológica de Microrganismos, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brasil
| | - Eliana Barreto-Bergter
- Laboratório de Química Biológica de Microrganismos, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brasil
| | - Sonia Rozental
- Laboratório de Biologia Celular de Fungos, Programa de Parasitologia e Biologia Celular, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brasil
| | - Eleonora Kurtenbach
- Laboratório de Biologia Molecular e Bioquímica de Proteínas, Programa de Biologia Molecular e Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brasil
- *Correspondence: Eleonora Kurtenbach,
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Morelli KA, Kerkaert JD, Cramer RA. Aspergillus fumigatus biofilms: Toward understanding how growth as a multicellular network increases antifungal resistance and disease progression. PLoS Pathog 2021; 17:e1009794. [PMID: 34437655 PMCID: PMC8389518 DOI: 10.1371/journal.ppat.1009794] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Aspergillus fumigatus is a saprophytic, filamentous fungus found in soils and compost and the causative agent of several pulmonary diseases in humans, birds, and other mammals. A. fumigatus and other filamentous fungi grow as networks of filamentous hyphae that have characteristics of a classic microbial biofilm. These characteristics include production of an extracellular matrix (ECM), surface adhesion, multicellularity, and increased antimicrobial drug resistance. A. fumigatus biofilm growth occurs in vivo at sites of infection, highlighting the importance of defining mechanisms underlying biofilm development and associated emergent properties. We propose that there are 3 distinct phases in the development of A. fumigatus biofilms: biofilm initiation, immature biofilm, and mature biofilm. These stages are defined both temporally and by unique genetic and structural changes over the course of development. Here, we review known mechanisms within each of these stages that contribute to biofilm structure, ECM production, and increased resistance to contemporary antifungal drugs. We highlight gaps in our understanding of biofilm development and function that when addressed are expected to aid in the development of novel antifungal therapies capable of killing filamentous fungal biofilms.
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Affiliation(s)
- Kaesi A. Morelli
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Joshua D. Kerkaert
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Robert A. Cramer
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
- * E-mail:
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7
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Lingo DE, Shukla N, Osmani AH, Osmani SA. Aspergillus nidulans biofilm formation modifies cellular architecture and enables light-activated autophagy. Mol Biol Cell 2021; 32:1181-1192. [PMID: 33826367 PMCID: PMC8351559 DOI: 10.1091/mbc.e20-11-0734] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
After growing on surfaces, including those of medical and industrial importance, fungal biofilms self-generate internal microenvironments. We previously reported that gaseous microenvironments around founder Aspergillus nidulans cells change during biofilm formation causing microtubules to disassemble under control of the hypoxic transcription factor SrbA. Here we investigate if biofilm formation might also promote changes to structures involved in exocytosis and endocytosis. During biofilm formation, the endoplasmic reticulum (ER) remained intact but ER exit sites and the Golgi apparatus were modified as were endocytic actin patches. The biofilm-driven changes required the SrbA hypoxic transcription factor and could be triggered by nitric oxide, further implicating gaseous regulation of biofilm cellular architecture. By tracking green fluorescent protein (GFP)-Atg8 dynamics, biofilm founder cells were also observed to undergo autophagy. Most notably, biofilm cells that had undergone autophagy were triggered into further autophagy by spinning disk confocal light. Our findings indicate that fungal biofilm formation modifies the secretory and endocytic apparatus and show that biofilm cells can also undergo autophagy that is reactivated by light. The findings provide new insights into the changes occurring in fungal biofilm cell biology that potentially impact their unique characteristics, including antifungal drug resistance.
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Affiliation(s)
- Dale E Lingo
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
| | - Nandini Shukla
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210.,The Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210
| | - Aysha H Osmani
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
| | - Stephen A Osmani
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
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8
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Kowalski CH, Morelli KA, Schultz D, Nadell CD, Cramer RA. Fungal biofilm architecture produces hypoxic microenvironments that drive antifungal resistance. Proc Natl Acad Sci U S A 2020; 117:22473-22483. [PMID: 32848055 PMCID: PMC7486789 DOI: 10.1073/pnas.2003700117] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Human fungal infections may fail to respond to contemporary antifungal therapies in vivo despite in vitro fungal isolate drug susceptibility. Such a discrepancy between in vitro antimicrobial susceptibility and in vivo treatment outcomes is partially explained by microbes adopting a drug-resistant biofilm mode of growth during infection. The filamentous fungal pathogen Aspergillus fumigatus forms biofilms in vivo, and during biofilm growth it has reduced susceptibility to all three classes of contemporary antifungal drugs. Specific features of filamentous fungal biofilms that drive antifungal drug resistance remain largely unknown. In this study, we applied a fluorescence microscopy approach coupled with transcriptional bioreporters to define spatial and temporal oxygen gradients and single-cell metabolic activity within A. fumigatus biofilms. Oxygen gradients inevitably arise during A. fumigatus biofilm maturation and are both critical for, and the result of, A. fumigatus late-stage biofilm architecture. We observe that these self-induced hypoxic microenvironments not only contribute to filamentous fungal biofilm maturation but also drive resistance to antifungal treatment. Decreasing oxygen levels toward the base of A. fumigatus biofilms increases antifungal drug resistance. Our results define a previously unknown mechanistic link between filamentous fungal biofilm physiology and contemporary antifungal drug resistance. Moreover, we demonstrate that drug resistance mediated by dynamic oxygen gradients, found in many bacterial biofilms, also extends to the fungal kingdom. The conservation of hypoxic drug-resistant niches in bacterial and fungal biofilms is thus a promising target for improving antimicrobial therapy efficacy.
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Affiliation(s)
- Caitlin H Kowalski
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - Kaesi A Morelli
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - Daniel Schultz
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - Carey D Nadell
- Department of Biological Sciences, Dartmouth College, Hanover, NH 03755
| | - Robert A Cramer
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755;
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Ahumada-Rudolph R, Novoa V, Becerra J. Morphological response to salinity, temperature, and pH changes by marine fungus Epicoccum nigrum. ENVIRONMENTAL MONITORING AND ASSESSMENT 2018; 191:35. [PMID: 30593600 DOI: 10.1007/s10661-018-7166-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Accepted: 12/17/2018] [Indexed: 06/09/2023]
Abstract
Epicoccum nigrum (strain LQRA39-P) was isolated from sediments collected in Chilean Patagonian fjords using microscopy and molecular techniques. We analyzed adaptive responses of cell wall morphology to salinity, temperature, and pH in order to explain the ability of E. nigrum to co-inhabit both marine and freshwater environments. For this purpose, E. nigrum was cultured in a series of media with variations in salinity (freshwater and seawater), pH (acidic, neutral, and basic), and temperature (5 to 25 °C). Changes were observed through transmission electron microscopy. A direct correlation between increased salinity and cell wall thickening (> 0.2 μm) was observed, along with a significant relationship between pH and the presence of extracellular polymeric substances (EPS) on the outside of the cell wall. The observed morphological changes could confirm that an ubiquitous fungus such as E. nigrum requires adaptive responses to co-inhabit freshwater, marine, and terrestrial substrates.
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Affiliation(s)
- Ramón Ahumada-Rudolph
- Laboratorio de Bioprocesos y Biotratamientos, Departamento de Ingeniería en Maderas, Universidad del Bío-Bío, Collao 1202, PO Box 5-C, Concepción, Chile
| | - Vanessa Novoa
- Department of Geography, School of Architecture, Urbanism and Geography, Universidad de Concepción, Víctor Lamas 1290, PO Box 160-C, Concepción, Chile.
| | - José Becerra
- Laboratorio de Química de Productos Naturales, Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Víctor Lamas 1290, PO Box 160-C, Concepción, Chile
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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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11
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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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