1
|
Oliveira-Garcia E, Tamang TM, Park J, Dalby M, Martin-Urdiroz M, Rodriguez Herrero C, Vu AH, Park S, Talbot NJ, Valent B. Clathrin-mediated endocytosis facilitates the internalization of Magnaporthe oryzae effectors into rice cells. THE PLANT CELL 2023:koad094. [PMID: 36976907 DOI: 10.1093/plcell/koad094] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 03/01/2023] [Accepted: 03/02/2023] [Indexed: 06/18/2023]
Abstract
Fungi and oomycetes deliver effectors into living plant cells to suppress defenses and control plant processes needed for infection. Little is known about the mechanism by which these pathogens translocate effector proteins across the plasma membrane into the plant cytoplasm. The blast fungus Magnaporthe oryzae secretes cytoplasmic effectors into a specialized biotrophic interfacial complex (BIC) before translocation. Here we show that cytoplasmic effectors within BICs are packaged into punctate membranous effector compartments that are occasionally observed in the host cytoplasm. Live cell imaging with fluorescently labeled proteins in rice (Oryza sativa) showed that these effector puncta colocalize with the plant plasma membrane and with CLATHRIN LIGHT CHAIN 1, a component of clathrin-mediated endocytosis (CME). Inhibiting CME using virus-induced gene silencing and chemical treatments resulted in cytoplasmic effectors in swollen BICs lacking effector puncta. By contrast, fluorescent marker co-localization, gene silencing and chemical inhibitor studies failed to support a major role for clathrin-independent endocytosis in effector translocation. Effector localization patterns indicated that cytoplasmic effector translocation occurs underneath appressoria before invasive hyphal growth. Taken together, this study provides evidence that cytoplasmic effector translocation is mediated by clathrin-mediated endocytosis in BICs and suggests a role for M. oryzae effectors in co-opting plant endocytosis.
Collapse
Affiliation(s)
- Ely Oliveira-Garcia
- Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, USA
- Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA
| | - Tej Man Tamang
- Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, USA
- Department of Horticulture and Natural Resources, Kansas State University, Manhattan, KS 66506, USA
| | - Jungeun Park
- Department of Horticulture and Natural Resources, Kansas State University, Manhattan, KS 66506, USA
| | - Melinda Dalby
- Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, USA
| | | | - Clara Rodriguez Herrero
- School of Biosciences, University of Exeter, Exeter, EX4 4QD, UK
- The Sainsbury Laboratory, University of East Anglia, Norwich Research Park, Norwich NR4 7UH, UK
| | - An Hong Vu
- Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA
| | - Sunghun Park
- Department of Horticulture and Natural Resources, Kansas State University, Manhattan, KS 66506, USA
| | - Nicholas J Talbot
- The Sainsbury Laboratory, University of East Anglia, Norwich Research Park, Norwich NR4 7UH, UK
| | - Barbara Valent
- Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, USA
| |
Collapse
|
2
|
Luo S, Wang H, Wang Z, Xu W, Tian R, Zhou J. Internalization of myriocin involved in energy and affected expression of genes and proteins in the endocytosis pathway in Fusarium oxysporum f. sp. niveum. BIOTECHNOL BIOTEC EQ 2022. [DOI: 10.1080/13102818.2022.2100721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Affiliation(s)
- Shiqi Luo
- Department of Horticulture, College of Life Science and Agroforestry, Qiqihar University, Qiqihar, Heilongjiang, PR China
- Department of Biology, Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, Heilongjiang, PR China
| | - Hengxu Wang
- Department of Horticulture, College of Life Science and Agroforestry, Qiqihar University, Qiqihar, Heilongjiang, PR China
- Department of Biology, Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, Heilongjiang, PR China
| | - Zhigang Wang
- Department of Horticulture, College of Life Science and Agroforestry, Qiqihar University, Qiqihar, Heilongjiang, PR China
- Department of Biology, Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, Heilongjiang, PR China
| | - Weihui Xu
- Department of Horticulture, College of Life Science and Agroforestry, Qiqihar University, Qiqihar, Heilongjiang, PR China
- Department of Biology, Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, Heilongjiang, PR China
| | - Renmao Tian
- Department of Food Safety, Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, IL, USA
| | - Jiaxin Zhou
- Department of Horticulture, College of Life Science and Agroforestry, Qiqihar University, Qiqihar, Heilongjiang, PR China
- Department of Biology, Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, Heilongjiang, PR China
| |
Collapse
|
3
|
Lee SK, Hong WJ, Silva J, Kim EJ, Park SK, Jung KH, Kim YJ. Global Identification of ANTH Genes Involved in Rice Pollen Germination and Functional Characterization of a Key Member, OsANTH3. FRONTIERS IN PLANT SCIENCE 2021; 12:609473. [PMID: 33927731 PMCID: PMC8076639 DOI: 10.3389/fpls.2021.609473] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 03/22/2021] [Indexed: 06/02/2023]
Abstract
Pollen in angiosperms plays a critical role in double fertilization by germinating and elongating pollen tubes rapidly in one direction to deliver sperm. In this process, the secretory vesicles deliver cell wall and plasma membrane materials, and excessive materials are sequestered via endocytosis. However, endocytosis in plants is poorly understood. AP180 N-terminal homology (ANTH) domain-containing proteins function as adaptive regulators for clathrin-mediated endocytosis in eukaryotic systems. Here, we identified 17 ANTH domain-containing proteins from rice based on a genome-wide investigation. Motif and phylogenomic analyses revealed seven asparagine-proline-phenylalanine (NPF)-rich and 10 NPF-less subgroups of these proteins, as well as various clathrin-mediated endocytosis-related motifs in their C-terminals. To investigate their roles in pollen germination, we performed meta-expression analysis of all genes encoding ANTH domain-containing proteins in Oryza sativa (OsANTH genes) in anatomical samples, including pollen, and identified five mature pollen-preferred OsANTH genes. The subcellular localization of four OsANTH proteins that were preferentially expressed in mature pollen can be consistent with their role in endocytosis in the plasma membrane. Of them, OsANTH3 represented the highest expression in mature pollen. Functional characterization of OsANTH3 using T-DNA insertional knockout and gene-edited mutants revealed that a mutation in OsANTH3 decreased seed fertility by reducing the pollen germination percentage in rice. Thus, our study suggests OsANTH3-mediated endocytosis is important for rice pollen germination.
Collapse
Affiliation(s)
- Su Kyoung Lee
- Graduate School of Biotechnology, Crop Biotech Institute, Kyung Hee University, Yongin, South Korea
| | - Woo-Jong Hong
- Graduate School of Biotechnology, Crop Biotech Institute, Kyung Hee University, Yongin, South Korea
| | - Jeniffer Silva
- Graduate School of Biotechnology, Crop Biotech Institute, Kyung Hee University, Yongin, South Korea
| | - Eui-Jung Kim
- Graduate School of Biotechnology, Crop Biotech Institute, Kyung Hee University, Yongin, South Korea
| | - Soon Ki Park
- School of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Ki-Hong Jung
- Graduate School of Biotechnology, Crop Biotech Institute, Kyung Hee University, Yongin, South Korea
| | - Yu-Jin Kim
- Department of Life Science and Environmental Biochemistry, Life and Industry Convergence Research Institute, Pusan National University, Miryang, South Korea
| |
Collapse
|
4
|
Baltussen TJH, Coolen JPM, Verweij PE, Dijksterhuis J, Melchers WJG. Identifying Conserved Generic Aspergillus spp. Co-Expressed Gene Modules Associated with Germination Using Cross-Platform and Cross-Species Transcriptomics. J Fungi (Basel) 2021; 7:270. [PMID: 33916245 PMCID: PMC8067318 DOI: 10.3390/jof7040270] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/27/2021] [Accepted: 03/29/2021] [Indexed: 12/26/2022] Open
Abstract
Aspergillus spp. is an opportunistic human pathogen that may cause a spectrum of pulmonary diseases. In order to establish infection, inhaled conidia must germinate, whereby they break dormancy, start to swell, and initiate a highly polarized growth process. To identify critical biological processes during germination, we performed a cross-platform, cross-species comparative analysis of germinating A. fumigatus and A. niger conidia using transcriptional data from published RNA-Seq and Affymetrix studies. A consensus co-expression network analysis identified four gene modules associated with stages of germination. These modules showed numerous shared biological processes between A. niger and A. fumigatus during conidial germination. Specifically, the turquoise module was enriched with secondary metabolism, the black module was highly enriched with protein synthesis, the darkgreen module was enriched with protein fate, and the blue module was highly enriched with polarized growth. More specifically, enriched functional categories identified in the blue module were vesicle formation, vesicular transport, tubulin dependent transport, actin-dependent transport, exocytosis, and endocytosis. Genes important for these biological processes showed similar expression patterns in A. fumigatus and A. niger, therefore, they could be potential antifungal targets. Through cross-platform, cross-species comparative analysis, we were able to identify biologically meaningful modules shared by A. fumigatus and A. niger, which underscores the potential of this approach.
Collapse
Affiliation(s)
- Tim J. H. Baltussen
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (J.P.M.C.); (P.E.V.); (W.J.G.M.)
- Center of Expertise in Mycology Radboudumc/CWZ, 6532 SZ Nijmegen, The Netherlands
| | - Jordy P. M. Coolen
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (J.P.M.C.); (P.E.V.); (W.J.G.M.)
- Center of Expertise in Mycology Radboudumc/CWZ, 6532 SZ Nijmegen, The Netherlands
| | - Paul E. Verweij
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (J.P.M.C.); (P.E.V.); (W.J.G.M.)
- Center of Expertise in Mycology Radboudumc/CWZ, 6532 SZ Nijmegen, The Netherlands
| | - Jan Dijksterhuis
- Westerdijk Fungal Biodiversity Institute, 3584 CT Utrecht, The Netherlands
| | - Willem J. G. Melchers
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands; (J.P.M.C.); (P.E.V.); (W.J.G.M.)
- Center of Expertise in Mycology Radboudumc/CWZ, 6532 SZ Nijmegen, The Netherlands
| |
Collapse
|
5
|
Papathoti NK, Saengchan C, Daddam JR, Thongprom N, Tonpho K, Thanh TL, Buensanteai N. Plant systemic acquired resistance compound salicylic acid as a potent inhibitor against SCF (SKP1-CUL1-F-box protein) mediated complex in Fusarium oxysporum by homology modeling and molecular dynamics simulations. J Biomol Struct Dyn 2020; 40:1472-1479. [PMID: 33047664 DOI: 10.1080/07391102.2020.1828168] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Fusarium oxysporum causes significant economic losses in many crop plants by causing root rot, necrosis, and wilting symptoms. Homology and molecular dynamics studies are promising tools for the detection in F. oxysporum of the systemic resistance compound, salicylic acid, for control of the SKP1-CUL1-F-box protein complex. The structure of SKP1-CUL1-F-box subunit Skp1 from F. oxysporum is produced by Modeler 9v7 for the conduct of docking studies. The Skp1 structure is based on the yeast Cdc4/Skp1 (PDB ID: 3MKS A) crystal structure collected by the Protein data bank. Applying molecular dynamic model simulation methods to the final predicted structure and further evaluated by 3D and PROCHECK test programmers, the final model is verified to be accurate. Applying GOLD 3.0.1, SCF Complex Skp1 is used to prevent stress-tolerant operation. The SKP1-CUL1-F-box model is predicted to be stabilized and tested as a stable docking structure. The predicted model of the SCF structure has been stabilized and confirmed to be a reliable structure for docking studies. The results indicated that GLN8, LYS9, VAL10, TRP11, GLU48, ASN49 in SCF complex are important determinant residues in binding as they have strong hydrogen bonding with salicylic acid, which showed best docking results with SKP1-CUL1-F-box complex subunit Skp1 with docking score 25.25KJ/mol. Insilco studies have been used to determine the mode of action of salicylic acid for Fusarium control. Salicylic acid hinders the SKP1-CUL1-F-box complex, which is important in protein-like interactions through hydrogen bodings. Results from docking studies have shown that the best energy for SKP1-CUL1-F-box was salicylic acid.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Narendra Kumar Papathoti
- School of Crop Production Technology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Chanon Saengchan
- School of Crop Production Technology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Jayasimha Rayulu Daddam
- Department of Cardiovascular and Mitochondrial Related Disease Research Center, Hualien Tzu Chi Hospital, Hualien, Taiwan
| | - Nattaya Thongprom
- School of Crop Production Technology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Kodchaphon Tonpho
- School of Crop Production Technology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Toan Le Thanh
- Crop Protection Department, College of Agriculture, Can Tho University, Can Tho city, Vietnam
| | - Natthiya Buensanteai
- School of Crop Production Technology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| |
Collapse
|
6
|
Horvat S, Yu Y, Böjte S, Teßmer I, Lowman DW, Ma Z, Williams DL, Beilhack A, Albrecht K, Groll J. Engineering Nanogels for Drug Delivery to Pathogenic Fungi Aspergillus fumigatus by Tuning Polymer Amphiphilicity. Biomacromolecules 2020; 21:3112-3121. [PMID: 32603103 DOI: 10.1021/acs.biomac.0c00489] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Invasive aspergillosis is a serious threat to immunodeficient and critically ill patients caused mainly by the fungus Aspergillus fumigatus. Here, poly(glycidol)-based nanogels (NGs) are proposed as delivery vehicles for antifungal agents for sustained drug release. NGs are formed by simple self-assembly of random copolymers, followed by oxidative cross-linking of thiol functionalities. We investigate the impact of copolymer amphiphilicity on NG interaction with mature fungal hyphae in order to select the optimal drug delivery system for model antifungal drug amphotericin B. The results show that drug-loaded NGs decrease minimal inhibitory concentration (MIC) for around four times and slow down the fungal biofilm synthesis at concentrations lower than MIC. Our results suggest that amphiphilicity of nanoparticle's polymer matrix is an important factor in understanding the action of nanocarriers toward fungal cells and should be considered in the development of nanoparticle-based antifungal therapy.
Collapse
Affiliation(s)
- Sonja Horvat
- Department for Functional Materials in Medicine and Dentistry and Bavarian Polymer Institute, University of Würzburg, Pleicherwall 2, 97070 Würzburg, Germany
| | - Yidong Yu
- Department of Medicine II, Center for Experimental Molecular Medicine, Würzburg University Hospital, Zinklesweg 10, 97078 Würzburg, Germany
| | - Szalbolcs Böjte
- Ingrid Tessmer's Lab, Rudolf Virchow Center, University of Würzburg, 97078 Würzburg, Germany
| | - Ingrid Teßmer
- Ingrid Tessmer's Lab, Rudolf Virchow Center, University of Würzburg, 97078 Würzburg, Germany
| | - Douglas W Lowman
- Department of Surgery, Quillen College of Medicine, Center of Excellence in Inflammation, Infectious Disease and Immunity, East Tennessee State University, Johnson City, Tennessee 37614-0575, United States
| | - Zuchao Ma
- Department of Surgery, Quillen College of Medicine, Center of Excellence in Inflammation, Infectious Disease and Immunity, East Tennessee State University, Johnson City, Tennessee 37614-0575, United States
| | - David L Williams
- Department of Surgery, Quillen College of Medicine, Center of Excellence in Inflammation, Infectious Disease and Immunity, East Tennessee State University, Johnson City, Tennessee 37614-0575, United States
| | - Andreas Beilhack
- Department of Medicine II, Center for Experimental Molecular Medicine, Würzburg University Hospital, Zinklesweg 10, 97078 Würzburg, Germany
| | - Krystyna Albrecht
- Department for Functional Materials in Medicine and Dentistry and Bavarian Polymer Institute, University of Würzburg, Pleicherwall 2, 97070 Würzburg, Germany
| | - Jürgen Groll
- Department for Functional Materials in Medicine and Dentistry and Bavarian Polymer Institute, University of Würzburg, Pleicherwall 2, 97070 Würzburg, Germany
| |
Collapse
|
7
|
Han X, Chen L, Li W, Zhang L, Zhang L, Zou S, Liang Y, Yu J, Dong H. Endocytic FgEde1 regulates virulence and autophagy in Fusarium graminearum. Fungal Genet Biol 2020; 141:103400. [PMID: 32387406 DOI: 10.1016/j.fgb.2020.103400] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 03/07/2020] [Accepted: 05/01/2020] [Indexed: 12/17/2022]
Abstract
Endocytosis plays critical roles in cellular processes, including nutrient uptake and signal transduction. Ede1 is an endocytic scaffolding protein that contributes to endocytic site initiation and maturation in yeast. However, the functions of Ede1 in phytopathogenic fungi are not known. Here, we identified functions of FgEde1 (FGSG_05182) in Fusarium graminearum. Deletion of FgEde1 resulted in defects in hyphal growth, conidiation and ascospore development. The FgEde1 deletion mutant showed reduced deoxynivalenol (DON) production and virulence in wheat. Furthermore, the FgEde1 deletion mutant also exhibited increased resistance to osmotic and oxidative stress as well as cell-wall perturbing agents. Importantly, deletion of FgEde1 increased the severity of autophagy in hyphae. Taken together, these results reveal that FgEde1 is involved in hyphal growth, asexual and sexual reproduction, virulence, stress responses, and autophagy in F. graminearum.
Collapse
Affiliation(s)
- Xuelian Han
- Key Laboratory of Agricultural Microbiology, College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| | - Lei Chen
- Key Laboratory of Agricultural Microbiology, College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| | - Weidong Li
- Key Laboratory of Agricultural Microbiology, College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| | - Li Zhang
- Key Laboratory of Agricultural Microbiology, College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| | - Liyuan Zhang
- Key Laboratory of Agricultural Microbiology, College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| | - Shenshen Zou
- Key Laboratory of Agricultural Microbiology, College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| | - Yuancun Liang
- Key Laboratory of Agricultural Microbiology, College of Plant Protection, Shandong Agricultural University, Taian 271018, China.
| | - Jinfeng Yu
- Key Laboratory of Agricultural Microbiology, College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| | - Hansong Dong
- Key Laboratory of Agricultural Microbiology, College of Plant Protection, Shandong Agricultural University, Taian 271018, China
| |
Collapse
|
8
|
Abstract
Filamentous fungi grow by adding cell wall and membrane exclusively at the apex of tubular structures called hyphae. Growth was previously believed to occur only through exocytosis at the Spitzenkörper, an organised body of secretory macro- and microvesicles found only in growing hyphae. More recent work has indicated that an area deemed the sub-apical collar is enriched for endocytosis and is also required for hyphal growth. It is now generally believed that polarity of filamentous fungi is achieved through the balancing of the processes of endocytosis and exocytosis at these two areas. This review is an update on the current progress and understanding surrounding the occurrence of endocytosis and its spatial regulation as they pertain to growth and pathogenicity in filamentous fungi.
Collapse
Affiliation(s)
- Blake Commer
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, USA
| | - Brian D Shaw
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, USA
| |
Collapse
|
9
|
MrArk1, an actin-regulating kinase gene, is required for endocytosis and involved in sustaining conidiation capacity and virulence in Metarhizium robertsii. Appl Microbiol Biotechnol 2019; 103:4859-4868. [PMID: 31025075 DOI: 10.1007/s00253-019-09836-6] [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: 02/22/2019] [Revised: 03/25/2019] [Accepted: 04/07/2019] [Indexed: 01/19/2023]
Abstract
Actin-regulating kinase (Ark) plays an important role in controlling endocytosis, which has been shown to be involved in the development and virulence of several fungal pathogens. However, it remains unclear whether Ark1 is required for the development and pathogenicity of an entomopathogenic fungus. Here, MrArk1 (MAA_03415), a homologue of yeast Ark1, was characterized in the insect pathogenic fungus, Metarhizium robertsii. Disruption of MrArk1 led to defects in endocytosis and a marked reduction (58%) in conidiation capacity. The reduced conidiation level was accompanied by repression of several key conidiation-related genes, including brlA, abaA, and wetA. Additionally, the deletion mutant showed a significant decrease in its tolerance to heat shock, but not to UV-B irradiation. Bioassays demonstrated attenuated virulence for the deletion mutant against Galleria mellonella via normal cuticle infection, accompanied by suppressed appressorium formation and reduced transcript levels of several genes involved in cuticle penetration. Taken together, our results indicate that MrArk1 is involved in the heat tolerance, sporulation, and virulence of M. robertsii, and thus is an important factor for sustaining the fungal potential against insect pests.
Collapse
|
10
|
Bartnicki-Garcia S, Garduño-Rosales M, Delgado-Alvarez DL, Mouriño-Pérez RR. Experimental measurement of endocytosis in fungal hyphae. Fungal Genet Biol 2018; 118:32-36. [PMID: 30017938 DOI: 10.1016/j.fgb.2018.07.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 06/27/2018] [Accepted: 07/01/2018] [Indexed: 11/15/2022]
Abstract
The present study examines the notion that polarized exocytosis in the tips of growing hyphae creates an excess of plasma membrane and thus the need for its removal by endocytosis. To measure endocytosis experimentally, we developed a photobleaching (FRAP) procedure to count endocytic events in hyphae of Neurospora crassa carrying a fluorescent tag on the actin-binding protein fimbrin (FIM-1-GFP). Given 40 nm as the average diameter of endocytic vesicles, we calculated that about 12.5% of the plasma membrane discharged in the apex becomes endocytosed in the subapex. According to our calculations, the GFP-tagged hyphae of N. crassa, measured under the constrained conditions of confocal microscopic examination, needed about 8800 vesicles/min to extend their plasma membrane or about 9800/min, if we include predicted demands for cell wall growth and extracellular secretion. Our findings support the notion that exocytosis and endocytosis operate in tandem with the latter serving as a compensatory process to remove any excess of plasma membrane generated by the intense exocytosis in the hyphal tips. Presumably, this tandem arrangement evolved to support the hallmark features of fungi namely rapid cell extension and abundant secretion of hydrolytic enzymes.
Collapse
Affiliation(s)
- Salomon Bartnicki-Garcia
- Departamento de Microbiología, CICESE (Centro de Investigación Científica y Educación Superior de Ensenada), Mexico
| | - Marisela Garduño-Rosales
- Departamento de Microbiología, CICESE (Centro de Investigación Científica y Educación Superior de Ensenada), Mexico
| | - Diego Luis Delgado-Alvarez
- Departamento de Microbiología, CICESE (Centro de Investigación Científica y Educación Superior de Ensenada), Mexico
| | - Rosa Reyna Mouriño-Pérez
- Departamento de Microbiología, CICESE (Centro de Investigación Científica y Educación Superior de Ensenada), Mexico.
| |
Collapse
|
11
|
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.
Collapse
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
| |
Collapse
|
12
|
Abstract
Filamentous fungi are a large and ancient clade of microorganisms that occupy a broad range of ecological niches. The success of filamentous fungi is largely due to their elongate hypha, a chain of cells, separated from each other by septa. Hyphae grow by polarized exocytosis at the apex, which allows the fungus to overcome long distances and invade many substrates, including soils and host tissues. Hyphal tip growth is initiated by establishment of a growth site and the subsequent maintenance of the growth axis, with transport of growth supplies, including membranes and proteins, delivered by motors along the cytoskeleton to the hyphal apex. Among the enzymes delivered are cell wall synthases that are exocytosed for local synthesis of the extracellular cell wall. Exocytosis is opposed by endocytic uptake of soluble and membrane-bound material into the cell. The first intracellular compartment in the endocytic pathway is the early endosomes, which emerge to perform essential additional functions as spatial organizers of the hyphal cell. Individual compartments within septated hyphae can communicate with each other via septal pores, which allow passage of cytoplasm or organelles to help differentiation within the mycelium. This article introduces the reader to more detailed aspects of hyphal growth in fungi.
Collapse
|
13
|
Huang L, Zhang S, Yin Z, Liu M, Li B, Zhang H, Zheng X, Wang P, Zhang Z. MoVrp1, a putative verprolin protein, is required for asexual development and infection in the rice blast fungus Magnaporthe oryzae. Sci Rep 2017; 7:41148. [PMID: 28117435 PMCID: PMC5259722 DOI: 10.1038/srep41148] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 12/15/2016] [Indexed: 01/04/2023] Open
Abstract
Endocytosis is a crucial cellular process in eukaryotic cells which involves clathrin and/or adaptor proteins, lipid kinases, phosphatases and the actin cytoskeleton. Verprolin proteins, such as Vrp1 in Saccharomyces cerevisiae, are conserved family proteins that regulate actin binding and endocytosis. Here, we identified and characterized MoVrp1 as the yeast Vrp1 homolog in Magnaporthe oryzae. Deletion of the MoVRP1 gene resulted in defects in vegetative growth, asexual development, and infection of the host plant. The ∆Movrp1 mutants also exhibited decreased extracellular peroxidase and laccase activities and showed defects in colony pigmentation, hyphal surface hydrophobicity, cell wall integrity, autophagy, endocytosis, and secretion of avirulent effector. Our studies provided new evidences that MoVrp1 involved in actin cytoskeleton is important for growth, morphogenesis, cellular trafficking, and fungal pathogenesis.
Collapse
Affiliation(s)
- Lin Huang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.,College of Forestry and Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Shengpei Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Ziyi Yin
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Muxing Liu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Bing Li
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Haifeng Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Xiaobo Zheng
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Ping Wang
- Department of Pediatrics, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70118, USA
| | - Zhengguang Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| |
Collapse
|
14
|
El-Mounadi K, Islam KT, Hernández-Ortiz P, Read ND, Shah DM. Antifungal mechanisms of a plant defensin MtDef4 are not conserved between the ascomycete fungi Neurospora crassa and Fusarium graminearum. Mol Microbiol 2016; 100:542-59. [PMID: 26801962 DOI: 10.1111/mmi.13333] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2016] [Indexed: 12/14/2022]
Abstract
Defensins play an important role in plant defense against fungal pathogens. The plant defensin, MtDef4, inhibits growth of the ascomycete fungi, Neurospora crassa and Fusarium graminearum, at micromolar concentrations. We have reported that MtDef4 is transported into the cytoplasm of these fungi and exerts its antifungal activity on intracellular targets. Here, we have investigated whether the antifungal mechanisms of MtDef4 are conserved in these fungi. We show that N. crassa and F. graminearum respond differently to MtDef4 challenge. Membrane permeabilization is required for the antifungal activity of MtDef4 against F. graminearum but not against N. crassa. We find that MtDef4 is targeted to different subcellular compartments in each fungus. Internalization of MtDef4 in N. crassa is energy-dependent and involves endocytosis. By contrast, MtDef4 appears to translocate into F. graminearum autonomously using a partially energy-dependent pathway. MtDef4 has been shown to bind to the phospholipid phosphatidic acid (PA). We provide evidence that the plasma membrane localized phospholipase D, involved in the biosynthesis of PA, is needed for entry of this defensin in N. crassa, but not in F. graminearum. To our knowledge, this is the first example of a defensin which inhibits the growth of two ascomycete fungi via different mechanisms.
Collapse
Affiliation(s)
| | - Kazi T Islam
- Donald Danforth Plant Science Center, St Louis, MO, 63132, USA
| | - Patricia Hernández-Ortiz
- Manchester Fungal Infection Group, Institution of Inflammation and Repair, University of Manchester, Manchester, M13 9NT, UK
| | - Nick D Read
- Manchester Fungal Infection Group, Institution of Inflammation and Repair, University of Manchester, Manchester, M13 9NT, UK
| | - Dilip M Shah
- Donald Danforth Plant Science Center, St Louis, MO, 63132, USA
| |
Collapse
|
15
|
Lara-Rojas F, Bartnicki-García S, Mouriño-Pérez RR. Localization and role of MYO-1, an endocytic protein in hyphae of Neurospora crassa. Fungal Genet Biol 2016; 88:24-34. [DOI: 10.1016/j.fgb.2016.01.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Revised: 01/15/2016] [Accepted: 01/19/2016] [Indexed: 10/22/2022]
|
16
|
Qi Z, Liu M, Dong Y, Zhu Q, Li L, Li B, Yang J, Li Y, Ru Y, Zhang H, Zheng X, Wang P, Zhang Z. The syntaxin protein (MoSyn8) mediates intracellular trafficking to regulate conidiogenesis and pathogenicity of rice blast fungus. THE NEW PHYTOLOGIST 2016; 209:1655-1667. [PMID: 26522477 DOI: 10.1111/nph.13710] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 09/14/2015] [Indexed: 06/05/2023]
Abstract
Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) mediate cellular membrane fusion and intracellular vesicle trafficking in eukaryotic cells, and are critical in the growth and development of pathogenic fungi such as Magnaporthe oryzae which causes rice blast. Rice blast is thought to involve distinct SNARE-mediated transport and secretion of fungal effector proteins into the host to modulate rice immunity. We have previously characterized two SNARE proteins, secretory protein (MoSec22) and vesicle-associated membrane protein (MoVam7), as being important in cellular transport and pathogenicity. Here, we show that syntaxin 8 (MoSyn8), a Qc-SNARE protein homolog, also plays important roles in growth, conidiation, and pathogenicity. The MoSYN8 deletion mutant (∆Mosyn8) mutant exhibits defects in endocytosis and F-actin organization, appressorium turgor pressure generation, and host penetration. In addition, the ∆Mosyn8 mutant cannot elaborate biotrophic invasion of the susceptible rice host, or secrete avirulence factors Avr-Pia (corresponding to the rice resistance gene Pia) and Avrpiz-t (the cognate Avr gene for the resistance gene Piz-t) proteins. Our study of MoSyn8 advances our understanding of SNARE proteins in effector secretion which underlies the normal physiology and pathogenicity of M. oryzae, and it sheds new light on the mechanism of the blight disease caused by M. oryzae.
Collapse
Affiliation(s)
- Zhongqiang Qi
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Muxing Liu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Yanhan Dong
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Qian Zhu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Lianwei Li
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Bing Li
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Jie Yang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Ying Li
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Yanyan Ru
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Haifeng Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Xiaobo Zheng
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Ping Wang
- Department of Pediatrics, Louisiana State University Health Sciences Center, New Orleans, LA, 70118, USA
| | - Zhengguang Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| |
Collapse
|
17
|
Anderson JP, Hane JK, Stoll T, Pain N, Hastie ML, Kaur P, Hoogland C, Gorman JJ, Singh KB. Proteomic Analysis of Rhizoctonia solani Identifies Infection-specific, Redox Associated Proteins and Insight into Adaptation to Different Plant Hosts. Mol Cell Proteomics 2016; 15:1188-203. [PMID: 26811357 PMCID: PMC4824849 DOI: 10.1074/mcp.m115.054502] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Indexed: 11/22/2022] Open
Abstract
Rhizoctonia solani is an important root infecting pathogen of a range of food staples worldwide including wheat, rice, maize, soybean, potato and others. Conventional resistance breeding strategies are hindered by the absence of tractable genetic resistance in any crop host. Understanding the biology and pathogenicity mechanisms of this fungus is important for addressing these disease issues, however, little is known about how R. solani causes disease. This study capitalizes on recent genomic studies by applying mass spectrometry based proteomics to identify soluble, membrane-bound and culture filtrate proteins produced under wheat infection and vegetative growth conditions. Many of the proteins found in the culture filtrate had predicted functions relating to modification of the plant cell wall, a major activity required for pathogenesis on the plant host, including a number found only under infection conditions. Other infection related proteins included a high proportion of proteins with redox associated functions and many novel proteins without functional classification. The majority of infection only proteins tested were confirmed to show transcript up-regulation during infection including a thaumatin which increased susceptibility to R. solani when expressed in Nicotiana benthamiana. In addition, analysis of expression during infection of different plant hosts highlighted how the infection strategy of this broad host range pathogen can be adapted to the particular host being encountered. Data are available via ProteomeXchange with identifier PXD002806.
Collapse
Affiliation(s)
- Jonathan P Anderson
- From the ‡CSIRO Agriculture, Floreat, Western Australia; §The University of Western Australia Institute of Agriculture, Crawley, Western Australia
| | - James K Hane
- From the ‡CSIRO Agriculture, Floreat, Western Australia
| | - Thomas Stoll
- ¶QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Nicholas Pain
- From the ‡CSIRO Agriculture, Floreat, Western Australia
| | - Marcus L Hastie
- ¶QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
| | | | | | - Jeffrey J Gorman
- ¶QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Karam B Singh
- From the ‡CSIRO Agriculture, Floreat, Western Australia; §The University of Western Australia Institute of Agriculture, Crawley, Western Australia;
| |
Collapse
|
18
|
Liu XH, Chen SM, Gao HM, Ning GA, Shi HB, Wang Y, Dong B, Qi YY, Zhang DM, Lu GD, Wang ZH, Zhou J, Lin FC. The small GTPase MoYpt7 is required for membrane fusion in autophagy and pathogenicity ofMagnaporthe oryzae. Environ Microbiol 2015; 17:4495-510. [DOI: 10.1111/1462-2920.12903] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Revised: 05/07/2015] [Accepted: 05/10/2015] [Indexed: 12/31/2022]
Affiliation(s)
- Xiao-Hong Liu
- State Key Laboratory for Rice Biology; Biotechnology Institute; Zhejiang University; Hangzhou 310058 China
| | - Si-Miao Chen
- College of Life Sciences; Fujian Agriculture and Forestry University; Fuzhou Fujian 350002 China
| | - Hui-Min Gao
- State Key Laboratory of Soil and Sustainable Agriculture; Institute of Soil Science; Chinese Academy Sciences; Nanjing 210008 China
| | - Guo-Ao Ning
- State Key Laboratory for Rice Biology; Biotechnology Institute; Zhejiang University; Hangzhou 310058 China
| | - Huan-Bin Shi
- State Key Laboratory for Rice Biology; Biotechnology Institute; Zhejiang University; Hangzhou 310058 China
| | - Yao Wang
- State Key Laboratory for Rice Biology; Biotechnology Institute; Zhejiang University; Hangzhou 310058 China
| | - Bo Dong
- Institute of Virology and Biotechnology; Zhejiang Academy of Agricultural Science; Hangzhou 310058 China
| | - Yao-Yao Qi
- Key Laboratory of Biopesticides and Chemical Biology; Ministry of Education; Fujian Agriculture and Forestry University; Fuzhou Fujian 350002 China
| | - Dong-Mei Zhang
- Key Laboratory of Biopesticides and Chemical Biology; Ministry of Education; Fujian Agriculture and Forestry University; Fuzhou Fujian 350002 China
| | - Guo-Dong Lu
- Key Laboratory of Biopesticides and Chemical Biology; Ministry of Education; Fujian Agriculture and Forestry University; Fuzhou Fujian 350002 China
| | - Zong-Hua Wang
- College of Life Sciences; Fujian Agriculture and Forestry University; Fuzhou Fujian 350002 China
- Key Laboratory of Biopesticides and Chemical Biology; Ministry of Education; Fujian Agriculture and Forestry University; Fuzhou Fujian 350002 China
| | - Jie Zhou
- College of Life Sciences; Fujian Agriculture and Forestry University; Fuzhou Fujian 350002 China
| | - Fu-Cheng Lin
- State Key Laboratory for Rice Biology; Biotechnology Institute; Zhejiang University; Hangzhou 310058 China
- China Tobacco Gene Research Center; Zhengzhou Tobacco Institute of CNTC; Zhengzhou 450001 China
| |
Collapse
|
19
|
|
20
|
Qi Y, Marlin MC, Liang Z, Berry WL, Janknecht R, Zhou J, Wang Z, Lu G, Li G. Distinct biochemical and functional properties of two Rab5 homologs from the rice blast fungus Magnaporthe oryzae. J Biol Chem 2014; 289:28299-309. [PMID: 25164815 DOI: 10.1074/jbc.m114.591503] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Rab5 is a key regulator of early endocytosis by promoting early endosomal fusion and motility. In this study, we have unexpectedly found distinct properties of the two Rab5 homologs (MoRab5A and MoRab5B) from Magnaporthe oryzae, a pathogenic fungus in plants whose infection causes rice blast disease. Like mammalian Rab5, MoRab5A and MoRab5B can bind to several Rab5 effectors in a GTP-dependent manner, including EEA1, Rabenosyn-5, and Rabaptin-5. However, MoRab5A shows distinct binding characteristics in the sense that both the wild-type and the GTP hydrolysis-defective constitutively active mutant bind the effectors equally well in GST pull-down assays, suggesting that MoRab5A is defective in GTP hydrolysis and mostly in the GTP-bound conformation in the cell. Indeed, GTP hydrolysis assays indicate that MoRab5A GTPase activity is dramatically lower than MoRab5B and human Rab5 and is insensitive to RabGAP5 stimulation. We have further identified a Pro residue in the switch I region largely responsible for the distinct MoRab5A properties by characterization of MoRab5A and MoRab5B chimeras and mutagenesis. The differences between MoRab5A and MoRab5B extend to their functions in the cell. Although they both target to early endosomes, only MoRab5B closely resembles human Rab5 in promoting early endosome fusion and stimulating fluid phase endocytosis. In contrast, MoRab5A correlates with another related early endosomal Rab, Rab22, in terms of the presence of the switch I Pro residue and the blocked GTPase activity. Our data thus identify MoRab5B as the Rab5 ortholog and suggest that MoRab5A specializes to perform a non-redundant function in endosomal sorting.
Collapse
Affiliation(s)
- Yaoyao Qi
- From the Key Laboratory of Biopesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China, and Departments of Biochemistry and Molecular Biology
| | | | - Zhimin Liang
- Departments of Biochemistry and Molecular Biology
| | | | - Ralf Janknecht
- Cell Biology, and Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| | - Jie Zhou
- From the Key Laboratory of Biopesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China, and
| | - Zonghua Wang
- From the Key Laboratory of Biopesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China, and
| | - Guodong Lu
- From the Key Laboratory of Biopesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China, and
| | - Guangpu Li
- Departments of Biochemistry and Molecular Biology, Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
| |
Collapse
|
21
|
Steinberg G. Endocytosis and early endosome motility in filamentous fungi. Curr Opin Microbiol 2014; 20:10-8. [PMID: 24835422 PMCID: PMC4148197 DOI: 10.1016/j.mib.2014.04.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Accepted: 04/21/2014] [Indexed: 10/25/2022]
Abstract
Hyphal growth of filamentous fungi requires microtubule-based long-distance motility of early endosomes. Since the discovery of this process in Ustilago maydis, our understanding of its molecular basis and biological function has greatly advanced. Studies in U. maydis and Aspergillus nidulans reveal a complex interplay of the motor proteins kinesin-3 and dynein, which co-operate to support bi-directional motion of early endosomes. Genetic screening has shed light on the molecular mechanisms underpinning motor regulation, revealing Hook protein as general motor adapters on early endosomes. Recently, fascinating insight into unexpected roles for endosome motility has emerged. This includes septin filament formation and cellular distribution of the machinery for protein translation.
Collapse
Affiliation(s)
- Gero Steinberg
- Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK.
| |
Collapse
|
22
|
Fayeulle A, Veignie E, Slomianny C, Dewailly E, Munch JC, Rafin C. Energy-dependent uptake of benzo[a]pyrene and its cytoskeleton-dependent intracellular transport by the telluric fungus Fusarium solani. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:3515-3523. [PMID: 24271730 DOI: 10.1007/s11356-013-2324-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 11/04/2013] [Indexed: 06/02/2023]
Abstract
In screening indigenous soil filamentous fungi for polycyclic aromatic hydrocarbons (PAHs) degradation, an isolate of the Fusarium solani was found to incorporate benzo[a]pyrene (BaP) into fungal hyphae before degradation and mineralization. The mechanisms involved in BaP uptake and intracellular transport remain unresolved. To address this, the incorporation of two PAHs, BaP, and phenanthrene (PHE) were studied in this fungus. The fungus incorporated more BaP into cells than PHE, despite the 400-fold higher aqueous solubility of PHE compared with BaP, indicating that PAH incorporation is not based on a simple diffusion mechanism. To identify the mechanism of BaP incorporation and transport, microscopic studies were undertaken with the fluorescence probes Congo Red, BODIPY®493/503, and FM®4-64, targeting different cell compartments respectively fungal cell walls, lipids, and endocytosis. The metabolic inhibitor sodium azide at 100 mM totally blocked BaP incorporation into fungal cells indicating an energy-requirement for PAH uptake into the mycelium. Cytochalasins also inhibited BaP uptake by the fungus and probably its intracellular transport into fungal hyphae. The perfect co-localization of BaP and BODIPY reveals that lipid bodies constitute the intracellular storage sites of BaP in F. solani. Our results demonstrate an energy-dependent uptake of BaP and its cytoskeleton-dependent intracellular transport by F. solani.
Collapse
Affiliation(s)
- Antoine Fayeulle
- Unité de Chimie Environnementale et Interactions sur le Vivant UCEIV EA 4492, ULCO, Dunkerque, 59140, France
| | | | | | | | | | | |
Collapse
|
23
|
Miguel-Rojas C, Hera C. Proteomic identification of potential target proteins regulated by the SCF(F) (bp1) -mediated proteolysis pathway in Fusarium oxysporum. MOLECULAR PLANT PATHOLOGY 2013; 14:934-945. [PMID: 23855991 PMCID: PMC6638928 DOI: 10.1111/mpp.12060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
F-box proteins function in the recruitment of proteins for SCF ubiquitination and proteasome degradation. Here, we studied the role of Fbp1, a nonessential F-box protein of the tomato pathogen Fusarium oxysporum f. sp. lycopersici. The Δfbp1 mutant showed a significant delay in the production of wilt symptoms on tomato plants and was impaired in invasive growth on cellophane membranes and on living plant tissue. To search for target proteins recruited by Fbp1, a combination of sodium dodecylsulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrix-assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) was used to compare proteins in mycelia of the wild-type and Δfbp1 mutant. The proteomic approach identified 41 proteins differing significantly in abundance between the two strains, 17 of which were more abundant in the Δfbp1 mutant, suggesting a possible regulation by proteasome degradation. Interestingly, several of the identified proteins were related to vesicle trafficking. Microscopic analysis revealed an impairment of the Δfbp1 strain in directional growth and in the structure of the Spitzenkörper, suggesting a role of Fbp1 in hyphal orientation. Our results indicate that Fbp1 regulates protein turnover and pathogenicity in F. oxysporum.
Collapse
Affiliation(s)
- Cristina Miguel-Rojas
- Departamento de Genética, Facultad de Ciencias, Universidad de Córdoba, 14071, Córdoba, Spain; Campus de Excelencia Internacional Agroalimentario, ceiA3, 14071, Córdoba, Spain
| | | |
Collapse
|
24
|
Chen G, Liu X, Zhang L, Cao H, Lu J, Lin F. Involvement of MoVMA11, a Putative Vacuolar ATPase c' Subunit, in Vacuolar Acidification and Infection-Related Morphogenesis of Magnaporthe oryzae. PLoS One 2013; 8:e67804. [PMID: 23826342 PMCID: PMC3694887 DOI: 10.1371/journal.pone.0067804] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 05/27/2013] [Indexed: 11/18/2022] Open
Abstract
Many functions of vacuole depend on the activity of vacuolar ATPase which is essential to maintain an acidic lumen and create the driving forces for massive fluxes of ions and metabolites through vacuolar membrane. In filamentous fungus Magnaportheoryzae, subcellular colocalization and quinacrine staining suggested that the V1V0 domains of V-ATPase were fully assembled and the vacuoles were kept acidic during infection-related developments. Targeted gene disruption of MoVMA11 gene, encoding the putative c' subunit of V-ATPase, impaired vacuolar acidification and mimicked the phenotypes of yeast V-ATPase mutants in the poor colony morphology, abolished asexual and sexual reproductions, selective carbon source utilization, and increased calcium and heavy metals sensitivities, however, not in the typical pH conditional lethality. Strikingly, aerial hyphae of the MoVMA11 null mutant intertwined with each other to form extremely thick filamentous structures. The results also implicated that MoVMA11 was involved in cell wall integrity and appressorium formation. Abundant non-melanized swollen structures and rare, small appressoria without penetration ability were produced at the hyphal tips of the ΔMovma11 mutant on onion epidermal cells. Finally, the MoVMA11 null mutant lost pathogenicity on both intact and wounded host leaves. Overall, our data indicated that MoVMA11, like other fungal VMA genes, is associated with numerous cellular functions and highlighted that V-ATPase is essential for infection-related morphogenesis and pathogenesis in M. oryzae.
Collapse
Affiliation(s)
- Guoqing Chen
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, China
| | - Xiaohong Liu
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, China
| | - Lilin Zhang
- College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Huijuan Cao
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, China
| | - Jianping Lu
- College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Fucheng Lin
- State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, China
- China Tobacco Gene Research Center, Zhengzhou Tobacco Institute of CNTC, Zhengzhou, China
| |
Collapse
|
25
|
Wang J, Du Y, Zhang H, Zhou C, Qi Z, Zheng X, Wang P, Zhang Z. The actin-regulating kinase homologue MoArk1 plays a pleiotropic function in Magnaporthe oryzae. MOLECULAR PLANT PATHOLOGY 2013; 14:470-82. [PMID: 23384308 PMCID: PMC3642230 DOI: 10.1111/mpp.12020] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Endocytosis is an essential cellular process in eukaryotic cells that involves concordant functions of clathrin and adaptor proteins, various protein and lipid kinases, phosphatases and the actin cytoskeleton. In Saccharomyces cerevisiae, Ark1p is a member of the serine/threonine protein kinase (SPK) family that affects profoundly the organization of the cortical actin cytoskeleton. To study the function of MoArk1, an Ark1p homologue identified in Magnaporthe oryzae, we disrupted the MoARK1 gene and characterized the ΔMoark1 mutant strain. The ΔMoark1 mutant exhibited various defects ranging from mycelial growth and conidial formation to appressorium-mediated host infection. The ΔMoark1 mutant also exhibited decreased appressorium turgor pressure and attenuated virulence on rice and barley. In addition, the ΔMoark1 mutant displayed defects in endocytosis and formation of the Spitzenkörper, and was hyposensitive to exogenous oxidative stress. Moreover, a MoArk1-green fluorescent protein (MoArk1-GFP) fusion protein showed an actin-like localization pattern by localizing to the apical regions of hyphae. This pattern of localization appeared to be regulated by the N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins MoSec22 and MoVam7. Finally, detailed analysis revealed that the proline-rich region within the MoArk1 serine/threonine kinase (S_TKc) domain was critical for endocytosis, subcellular localization and pathogenicity. These results collectively suggest that MoArk1 exhibits conserved functions in endocytosis and actin cytoskeleton organization, which may underlie growth, cell wall integrity and virulence of the fungus.
Collapse
Affiliation(s)
- Jiamei Wang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Giraldo MC, Dagdas YF, Gupta YK, Mentlak TA, Yi M, Martinez-Rocha AL, Saitoh H, Terauchi R, Talbot NJ, Valent B. Two distinct secretion systems facilitate tissue invasion by the rice blast fungus Magnaporthe oryzae. Nat Commun 2013; 4:1996. [PMID: 23774898 PMCID: PMC3709508 DOI: 10.1038/ncomms2996] [Citation(s) in RCA: 256] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 05/09/2013] [Indexed: 12/30/2022] Open
Abstract
To cause plant diseases, pathogenic micro-organisms secrete effector proteins into host tissue to suppress immunity and support pathogen growth. Bacterial pathogens have evolved several distinct secretion systems to target effector proteins, but whether fungi, which cause the major diseases of most crop species, also require different secretory mechanisms is not known. Here we report that the rice blast fungus Magnaporthe oryzae possesses two distinct secretion systems to target effectors during plant infection. Cytoplasmic effectors, which are delivered into host cells, preferentially accumulate in the biotrophic interfacial complex, a novel plant membrane-rich structure associated with invasive hyphae. We show that the biotrophic interfacial complex is associated with a novel form of secretion involving exocyst components and the Sso1 t-SNARE. By contrast, effectors that are secreted from invasive hyphae into the extracellular compartment follow the conventional secretory pathway. We conclude that the blast fungus has evolved distinct secretion systems to facilitate tissue invasion.
Collapse
Affiliation(s)
- Martha C. Giraldo
- Department of Plant Pathology, Kansas State University, Manhattan, Kansas 66506, USA
- These authors contributed equally to this work
| | - Yasin F. Dagdas
- School of Biosciences, University of Exeter, Exeter, EX4 4QD, UK
- These authors contributed equally to this work
| | - Yogesh K. Gupta
- School of Biosciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Thomas A. Mentlak
- School of Biosciences, University of Exeter, Exeter, EX4 4QD, UK
- Present address: Cambridge Consultants Ltd, Cambridge, CB4 0DW, UK
| | - Mihwa Yi
- Department of Plant Pathology, Kansas State University, Manhattan, Kansas 66506, USA
| | - Ana Lilia Martinez-Rocha
- School of Biosciences, University of Exeter, Exeter, EX4 4QD, UK
- Present address: Department of Molecular Phytopathology and Genetics, University of Hamburg, Biozentrum Klein Flottbek, D-22609 Hamburg, Germany
| | - Hiromasa Saitoh
- Iwate Biotechnology Research Center, Kitakami, Iwate 024-0003, Japan
| | - Ryohei Terauchi
- Iwate Biotechnology Research Center, Kitakami, Iwate 024-0003, Japan
| | | | - Barbara Valent
- Department of Plant Pathology, Kansas State University, Manhattan, Kansas 66506, USA
| |
Collapse
|
27
|
Muñoz A, Marcos JF, Read ND. Concentration-dependent mechanisms of cell penetration and killing by the de novo designed antifungal hexapeptide PAF26. Mol Microbiol 2012; 85:89-106. [DOI: 10.1111/j.1365-2958.2012.08091.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
28
|
Echauri-Espinosa RO, Callejas-Negrete OA, Roberson RW, Bartnicki-García S, Mouriño-Pérez RR. Coronin is a component of the endocytic collar of hyphae of Neurospora crassa and is necessary for normal growth and morphogenesis. PLoS One 2012; 7:e38237. [PMID: 22693603 PMCID: PMC3365027 DOI: 10.1371/journal.pone.0038237] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 05/01/2012] [Indexed: 01/02/2023] Open
Abstract
Coronin plays a major role in the organization and dynamics of actin in yeast. To investigate the role of coronin in a filamentous fungus (Neurospora crassa), we examined its subcellular localization using fluorescent proteins and the phenotypic consequences of coronin gene (crn-1) deletion in hyphal morphogenesis, Spitzenkörper behavior and endocytosis. Coronin-GFP was localized in patches, forming a subapical collar near the hyphal apex; significantly, it was absent from the apex. The subapical patches of coronin colocalized with fimbrin, Arp2/3 complex, and actin, altogether comprising the endocytic collar. Deletion of crn-1 resulted in reduced hyphal growth rates, distorted hyphal morphology, uneven wall thickness, and delayed establishment of polarity during germination; it also affected growth directionality and increased branching. The Spitzenkörper of Δcrn-1 mutant was unstable; it appeared and disappeared intermittently giving rise to periods of hyphoid-like and isotropic growth respectively. Uptake of FM4-64 in Δcrn-1 mutant indicated a partial disruption in endocytosis. These observations underscore coronin as an important component of F-actin remodeling in N. crassa. Although coronin is not essential in this fungus, its deletion influenced negatively the operation of the actin cytoskeleton involved in the orderly deployment of the apical growth apparatus, thus preventing normal hyphal growth and morphogenesis.
Collapse
Affiliation(s)
- Ramon O. Echauri-Espinosa
- Departamento de Microbiología, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Baja California, México
| | - Olga A. Callejas-Negrete
- Departamento de Microbiología, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Baja California, México
| | - Robert W. Roberson
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Salomon Bartnicki-García
- Departamento de Microbiología, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Baja California, México
| | - Rosa R. Mouriño-Pérez
- Departamento de Microbiología, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Baja California, México
- * E-mail:
| |
Collapse
|
29
|
Inoue K, Tsurumi T, Ishii H, Park P, Ikeda K. Cytological evaluation of the effect of azoxystrobin and alternative oxidase inhibitors in Botrytis cinerea. FEMS Microbiol Lett 2011; 326:83-90. [PMID: 22092932 DOI: 10.1111/j.1574-6968.2011.02438.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 10/09/2011] [Accepted: 10/10/2011] [Indexed: 11/29/2022] Open
Abstract
Azoxystrobin (AZ), a strobilurin-derived fungicide, is known to inhibit mitochondrial respiration in fungi by blocking the electron transport chain in the inner mitochondrial membrane. Germination was strongly inhibited when Botrytis cinerea spore suspension was treated with AZ and the alternative oxidase (AOX) inhibitors, salicylhydroxamic acid (SHAM) and n-propyl gallate. However, chemical death indicators trypan blue and propidium iodide showed that those spores were still alive. When the spore suspension in the AZ and SHAM solution was replaced with distilled water, the germination rate almost recovered, at least during the first 2 days of incubation with AZ and SHAM solution. No morphological alteration was detected in the cells treated with AZ and SHAM, especially in mitochondria, using transmission electron microscopy. Therefore, simultaneous application of AZ and AOX inhibitors has a fungistatic, rather than a fungicidal, action.
Collapse
Affiliation(s)
- Kanako Inoue
- Stress Cytology Laboratory, Graduate School of Agriculture, Kobe University, Kobe, Japan
| | | | | | | | | |
Collapse
|
30
|
Shaw BD, Chung DW, Wang CL, Quintanilla LA, Upadhyay S. A role for endocytic recycling in hyphal growth. Fungal Biol 2011; 115:541-6. [PMID: 21640317 DOI: 10.1016/j.funbio.2011.02.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Accepted: 02/10/2011] [Indexed: 11/24/2022]
Abstract
Actin plays multiple complex roles in cell growth and cell shape. Recently it was demonstrated that actin patches, which represent sites of endocytosis, are present in a sub-apical collar at growing tips of hyphae and germ tubes of filamentous fungi. It is now clear that this zone of endocytosis is necessary for filamentous growth to proceed. In this review evidence for the role of these endocytic sites in hyphal growth is examined. One possibility if that the role of the sub-apical collar is associated with endocytic recycling of polarized material at the hyphal tip. The 'Apical Recycling Model' accounts for this role and predicts the need for a balance between endocytosis and exocytosis at the hyphal tip to control growth and cell shape. Other cell differentiation events, including appressorium formation and Aspergillus conidiophore development may also be explained by this model.
Collapse
Affiliation(s)
- Brian D Shaw
- Program for the Biology of Filamentous Fungi, Department of Plant Pathology and Microbiology, 2132 TAMU, Texas A&M University, College Station, TX 2132, USA.
| | | | | | | | | |
Collapse
|
31
|
Dou X, Wang Q, Qi Z, Song W, Wang W, Guo M, Zhang H, Zhang Z, Wang P, Zheng X. MoVam7, a conserved SNARE involved in vacuole assembly, is required for growth, endocytosis, ROS accumulation, and pathogenesis of Magnaporthe oryzae. PLoS One 2011; 6:e16439. [PMID: 21283626 PMCID: PMC3025985 DOI: 10.1371/journal.pone.0016439] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2010] [Accepted: 12/16/2010] [Indexed: 11/18/2022] Open
Abstract
Soluble NSF attachment protein receptor (SNARE) proteins play a central role in membrane fusion and vesicle transport of eukaryotic organisms including fungi. We previously identified MoSce22 as a homolog of Saccharomyces cerevisiae SNARE protein Sec22 to be involved in growth, stress resistance, and pathogenicity of Magnaporthe oryzae. Here, we provide evidences that MoVam7, an ortholog of S. cerevisiae SNARE protein Vam7, exerts conserved functions in vacuolar morphogenesis and functions in pathogenicity of M. oryzae. Staining with neutral red and FM4-64 revealed the presence of abnormal fragmented vacuoles and an absence of the Spitzenkörper body in the ΔMovam7 mutant. The ΔMovam7 mutant also exhibited reduced vegetative growth, poor conidiation, and failure to produce the infection structure appressorium. Additionally, treatments with cell wall perturbing agents indicated weakened cell walls and altered distributions of the cell wall component chitin. Furthermore, the ΔMovam7 mutant showed a reduced accumulation of reactive oxygen species (ROS) in the hyphal apex and failed to cause diseases on the rice plant. In summary, our studies indicate that MoVam7, like MoSec22, is a component of the SNARE complex whose functions in vacuole assembly also underlies the growth, conidiation, appressorium formation, and pathogenicity of M. oryzae. Further studies of MoVam7, MoSec22, and additional members of the SNARE complex are likely to reveal critical mechanisms in vacuole formation and membrane trafficking that is linked to fungal pathogenicity.
Collapse
Affiliation(s)
- Xianying Dou
- Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, and Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Qi Wang
- Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, and Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Zhongqiang Qi
- Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, and Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Wenwen Song
- Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, and Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Wei Wang
- Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, and Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Min Guo
- Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, and Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Haifeng Zhang
- Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, and Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Zhengguang Zhang
- Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, and Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- * E-mail:
| | - Ping Wang
- Department of Pediatrics and Research Institute for Children, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States of America
| | - Xiaobo Zheng
- Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, and Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| |
Collapse
|
32
|
Saitoh H, Fujisawa S, Ito A, Mitsuoka C, Berberich T, Tosa Y, Asakura M, Takano Y, Terauchi R. SPM1âencoding a vacuole-localized protease is required for infection-related autophagy of the rice blast fungusMagnaporthe oryzae. FEMS Microbiol Lett 2009; 300:115-21. [DOI: 10.1111/j.1574-6968.2009.01769.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
33
|
Lewis MW, Robalino IV, Keyhani NO. Uptake of the fluorescent probe FM4-64 by hyphae and haemolymph-derived in vivo hyphal bodies of the entomopathogenic fungus Beauveria bassiana. Microbiology (Reading) 2009; 155:3110-3120. [DOI: 10.1099/mic.0.029165-0] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The entomopathogenic fungus Beauveria bassiana is under intensive study as a pest biological control agent. B. bassiana produces several distinct single-cell types that include aerial conidia, in vitro blastospores and submerged conidia. Under appropriate nutrient conditions these cells can elaborate germ tubes that form hyphae, which in turn lead to the formation of a fungal mycelium. In addition, B. bassiana displays a dimorphic transition, producing in vivo specific yeast-like hyphal bodies during growth in the arthropod haemolymph. The amphiphilic styryl dye FM4-64 was used to investigate internalization and morphological features of in vitro and in vivo insect haemolymph-derived B. bassiana cells. In vitro blastospores and submerged conidia displayed a punctate pattern of internal labelling, whereas aerial conidia failed to internalize the dye under the conditions tested. FM4-64 was also taken up into both apical and subapical compartments of living hyphae in a time-dependent manner, with clearly observable vesicle labelling. Internalization, where occurring, was reversibly disrupted by lowering the temperature of the assay or by treatment with azide/fluoride and latrunculin A. Treatment with cytochalasin D and monensin also caused abnormal vesicle trafficking, although some staining of vesicles was noted. Fungal cells derived from infected Heliothis virescens haemolymph (in vivo cells) actively internalized FM4-64. The in vivo blastospores or hyphal bodies displayed bright membrane and internal vesicle staining, although diffuse staining of internal structures was also visible. These results suggest active uptake by different developmental stages of B. bassiana, including haemolymph-derived cells that can evade the insect immune system.
Collapse
Affiliation(s)
- Michael W. Lewis
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611, USA
| | - Ines V. Robalino
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611, USA
| | - Nemat O. Keyhani
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611, USA
| |
Collapse
|
34
|
Palma-Guerrero J, Huang IC, Jansson HB, Salinas J, Lopez-Llorca L, Read N. Chitosan permeabilizes the plasma membrane and kills cells of Neurospora crassa in an energy dependent manner. Fungal Genet Biol 2009; 46:585-94. [DOI: 10.1016/j.fgb.2009.02.010] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2009] [Accepted: 02/26/2009] [Indexed: 11/28/2022]
|
35
|
Van Leeuwen MR, Golovina EA, Dijksterhuis J. The polyene antimycotics nystatin and filipin disrupt the plasma membrane, whereas natamycin inhibits endocytosis in germinating conidia of Penicillium discolor. J Appl Microbiol 2009; 106:1908-18. [PMID: 19228256 DOI: 10.1111/j.1365-2672.2009.04165.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
AIMS To investigate the differences in membrane permeability and the effect on endocytosis of the polyene antimycotics nystatin, filipin and natamycin on germinating fungal conidia. METHODS AND RESULTS The model system was Penicillium discolor, a food spoilage fungus. Filipin resulted in permeabilization of germinating conidia for the fluorescent probes TOTO-1 and FM4-64, but not for ferricyanide ions. Nystatin caused influx of all these compounds while natamycin did not. Untreated germinating conidia internalize the endocytic marker FM4-64. Pretreatment of germinating conidia with natamycin showed a dose and time dependent inhibition of endocytosis as judged by the lack of formation of early endosomal compartments. CONCLUSIONS The results obtained from this study indicated that, unlike nystatin and filipin, natamycin is unable to permeabilize germinating conidia, but interferes with endocytosis in a dose and time dependent manner. SIGNIFICANCE AND IMPACT OF THE STUDY Natamycin acts via a different mode of action than other polyene antimycotics. These results offer useful information for new strategies to prevent fungal spoilage on food products and infection on agricultural crops. For laboratory use, natamycin can be used as a specific inhibitor of early endocytosis in fungal cells.
Collapse
Affiliation(s)
- M R Van Leeuwen
- Applied and Industrial Mycology, CBS/Fungal Biodiversity Centre, Utrecht, The Netherlands
| | | | | |
Collapse
|
36
|
Upadhyay S, Shaw BD. The role of actin, fimbrin and endocytosis in growth of hyphae in Aspergillus nidulans. Mol Microbiol 2008; 68:690-705. [PMID: 18331474 DOI: 10.1111/j.1365-2958.2008.06178.x] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Filamentous fungi are ideal systems to study the process of polarized growth, as their life cycle is dominated by hyphal growth exclusively at the cell apex. The actin cytoskeleton plays an important role in this growth. Until now, there have been no tools to visualize actin or the actin-binding protein fimbrin in live cells of a filamentous fungus. We investigated the roles of actin (ActA) and fimbrin (FimA) in hyphal growth in Aspergillus nidulans. We examined the localization of ActA::GFP and FimA::GFP in live cells, and each displayed a similar localization pattern. In actively growing hyphae, cortical ActA::GFP and FimA::GFP patches were highly mobile throughout the hypha and were concentrated near hyphal apices. A patch-depleted zone occupied the apical 0.5 microm of growing hypha. Both FimA::GFP and Act::GFP also localize transiently to septa. Movement and later localization of both was compromised after cytochalasin treatment. Disruption of fimA resulted in delayed polarity establishment during conidium germination, abnormal hyphal growth and endocytosis defects in apolar cells. Endocytosis was severely impaired in apolar fimA disruption cells. Our data support a novel apical recycling model which indicates a critical role for actin patch-mediated endocytosis to maintain polarized growth at the apex.
Collapse
Affiliation(s)
- Srijana Upadhyay
- Program for the Biology of Filamentous Fungi, Department of Plant Pathology and Microbiology, Texas A&M University, 2132 TAMU, College Station, TX 77843, USA
| | | |
Collapse
|
37
|
Lisboa S, Scherer GEF, Quader H. Localized endocytosis in tobacco pollen tubes: visualisation and dynamics of membrane retrieval by a fluorescent phospholipid. PLANT CELL REPORTS 2008; 27:21-8. [PMID: 17786450 DOI: 10.1007/s00299-007-0437-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2007] [Revised: 08/02/2007] [Accepted: 08/08/2007] [Indexed: 05/17/2023]
Abstract
Two modes of endocytosis are known to occur in eucaryotic cells: fluid phase and receptor-mediated endocytosis. Fluid-phase endocytosis in plant cells resembles the retrieval of excess plasma membrane material previously incorporated by exocytosis. Pollen tubes need to carry out strong membrane retrieval due to their fast polar tip growth. Plasma membrane labelling of pollen tubes, grown in suspension, was achieved by the incorporation of a fluorescently modified phospholipid, 1,2-bis-(4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-undecanoyl)-sn-glycero-3-phosphocholine (20 microM) and measured with a confocal laser-scanning microscope. Time course experiments revealed a highly localised and relatively fast plasma membrane retrieval below the tip within the first 5 min after phospholipid application. The retrieved fluorescent plasma membrane was quickly re-integrated into parts of the endomembrane pool and then redistributed to the pollen tube base and very tip of the apex, with the exception of the cortical endoplasmic reticulum (ER) and the mitochondria even after 1-h incubation period. Low temperature (10 degrees C) and the actin filament depolymerizing cytochalasin D (2 microM) completely abolished plasma membrane retrieval, whereas the microtubule destabilizing herbicide oryzalin (1 microM) had no effect. Our results provide strong support for a highly localised endocytotic pathway in tobacco pollen tubes. Passive uptake of bis-Bodipy FL C(11)-phosphocholine by mere penetration can be excluded. It is a valuable alternative to the styryl dyes often used in endocytotic studies, and may also be used to follow lipid turnover because membrane flow of labelled membranes occurs apparently not in a default manner as ascertained by its fast distribution.
Collapse
Affiliation(s)
- S Lisboa
- Biozentrum Klein Flottbek, University of Hamburg, Ohnhorst-Str. 18, 22609, Hamburg, Germany
| | | | | |
Collapse
|
38
|
Palma-Guerrero J, Jansson HB, Salinas J, Lopez-Llorca LV. Effect of chitosan on hyphal growth and spore germination of plant pathogenic and biocontrol fungi. J Appl Microbiol 2007; 104:541-53. [PMID: 17927761 DOI: 10.1111/j.1365-2672.2007.03567.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To investigate the toxic effect of chitosan on important root pathogenic and biocontrol fungi (nematophagous, entomopathogenic and mycoparasitic). METHODS AND RESULTS We have used standard bioassays to investigate the effect of chitosan on colony growth and developed bioassays to test spore germination. The results showed that the root pathogenic and mycoparasitic fungi tested were more sensitive to chitosan than nematophagous and entomopathogenic fungi. Chitosanases (and perhaps related enzymes) are involved in the resistance to chitosan. Two fungi, one sensitive to chitosan, Fusarium oxysporum f. sp. radicis-lycopersici, and one less sensitive, Pochonia chlamydosporia, were selected for ultrastructural investigations. Transmission electron microscopy revealed differences in the ultrastructural alterations caused by chitosan in the spores of the plant pathogenic fungus and in those of the nematophagous fungus. Confocal laser microscopy showed that Rhodamine-labelled chitosan enters rapidly into conidia of both fungi, in an energy-dependent process. CONCLUSIONS Nematophagous and entomopathogenic fungi are rather resistant to the toxic effect of chitosan. Resistance of nematophagous and entomopathogenic fungi to chitosan could be associated with their high extracellular chitosanolytic activity. Furthermore, ultrastructural damage is much more severe in the chitosan sensitive fungus. SIGNIFICANCE AND IMPACT OF THE STUDY The results of this paper suggest that biocontrol fungi tested could be combined with chitosan for biological control of plant pathogens and pests.
Collapse
Affiliation(s)
- J Palma-Guerrero
- Laboratory of Plant Pathology, Multidisciplinary Institute for Environmental Studies (MIES) Ramón Margalef, Department of Marine Sciences and Applied Biology, University of Alicante, Alicante, Spain
| | | | | | | |
Collapse
|
39
|
Endocytosis in the shiitake mushroom Lentinula edodes and involvement of GTPase LeRAB7. EUKARYOTIC CELL 2007; 6:2406-18. [PMID: 17921351 DOI: 10.1128/ec.00222-07] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Endocytosis is the process by which substrates enter a cell without passing through the plasma membrane but rather invaginate the cell membrane and form intracellular vesicles. Rab7 regulates endocytic trafficking between early and late endosomes and between late endosomes and lysosomes. LeRab7 in Lentinula edodes is strongly homologous to Rab7 in Homo sapiens. Receptors for activated C kinase-1 (LeRACK1) and Rab5 GTPase (LeRAB5) were isolated as interacting partners of LeRab7, and the interactions were confirmed by in vivo and in vitro protein interaction assays. The three genes showed differential expression in the various developmental stages of the mushroom. In situ hybridization showed that the three transcripts were localized in regions of active growth, such as the outer region of trama cells, and the subhymenium of the hymenophore of mature fruiting bodies and the prehymenophore of young fruiting bodies. The existence of endocytosis in the mycelium and hymenophores was confirmed by the internalization of FM4-64. LeRAB7 was partially colocalized with the AM4-64 and was located in the late endocytic pathway. This is the first report of the presence of endocytosis in homobasidiomycetes. LeRAB7, LeRAB5, and LeRACK1 may contribute to the growth of L. edodes and cell differentiation in hymenophores.
Collapse
|
40
|
Thompson SEM, Callow JA, Callow ME, Wheeler GL, Taylor AR, Brownlee C. Membrane recycling and calcium dynamics during settlement and adhesion of zoospores of the green alga Ulva linza. PLANT, CELL & ENVIRONMENT 2007; 30:733-44. [PMID: 17470149 DOI: 10.1111/j.1365-3040.2007.01661.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Recruitment of individuals of the marine alga Ulva linza on to a suitable habitat involves the settlement of motile zoospores on to a substratum during which a preformed adhesive is secreted by vesicular exocytosis. The fluorescent styryl dye FM 1-43 and fluorescent Ca(2+) indicators were used to follow membrane cycling and changes in cytosolic Ca(2+) ([Ca(2+)](cyt)) associated with settlement. When swimming zoospores were exposed continuously to FM 1-43, the plasma membrane was preferentially labelled. During settlement, FM 1-43-labelled plasma membrane was rapidly internalized reflecting high membrane turnover. The internalized membrane was focused into a discrete region indicating targeting of membrane to an endosome-like compartment. Acetoxymethyl (AM)-ester derivatives were found to be unsuitable for monitoring [Ca(2+)](cyt) because the dyes were rapidly sequestered from the cytoplasm into sub-cellular compartments. [Ca(2+)](cyt) was, however, reliably measured using dextran-conjugated calcium indicators delivered into cells using a biolistic technique. Cells loaded with Oregon Green BAPTA-1 dextran (Invitrogen, Paisley, UK) showed diffuse cytosolic loading and reliably responded to imposed changes in [Ca(2+)](cyt). During settlement, zoospores exhibited both localized and diffuse increases in [Ca(2+)](cyt) implying a role for [Ca(2+)](cyt) in exocytosis of the adhesive.
Collapse
Affiliation(s)
- S E M Thompson
- School of Biosciences, The University of Birmingham, Birmingham, and Marine Biological Association, The Laboratory, Citadel Hill, Plymouth, UK
| | | | | | | | | | | |
Collapse
|
41
|
Kankanala P, Czymmek K, Valent B. Roles for rice membrane dynamics and plasmodesmata during biotrophic invasion by the blast fungus. THE PLANT CELL 2007; 19:706-24. [PMID: 17322409 PMCID: PMC1867340 DOI: 10.1105/tpc.106.046300] [Citation(s) in RCA: 381] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Revised: 01/05/2007] [Accepted: 01/30/2007] [Indexed: 05/14/2023]
Abstract
Rice blast disease is caused by the hemibiotrophic fungus Magnaporthe oryzae, which invades living plant cells using intracellular invasive hyphae (IH) that grow from one cell to the next. The cellular and molecular processes by which this occurs are not understood. We applied live-cell imaging to characterize the spatial and temporal development of IH and plant responses inside successively invaded rice (Oryza sativa) cells. Loading experiments with the endocytotic tracker FM4-64 showed dynamic plant membranes around IH. IH were sealed in a plant membrane, termed the extra-invasive hyphal membrane (EIHM), which showed multiple connections to peripheral rice cell membranes. The IH switched between pseudohyphal and filamentous growth. Successive cell invasions were biotrophic, although each invaded cell appeared to have lost viability when the fungus moved into adjacent cells. EIHM formed distinct membrane caps at the tips of IH that initially grew in neighboring cells. Time-lapse imaging showed IH scanning plant cell walls before crossing, and transmission electron microscopy showed IH preferentially contacting or crossing cell walls at pit fields. This and additional evidence strongly suggest that IH co-opt plasmodesmata for cell-to-cell movement. Analysis of biotrophic blast invasion will significantly contribute to our understanding of normal plant processes and allow the characterization of secreted fungal effectors that affect these processes.
Collapse
Affiliation(s)
- Prasanna Kankanala
- Department of Plant Pathology, Kansas State University, Manhattan, Kansas 66506, USA
| | | | | |
Collapse
|
42
|
Xu JR, Zhao X, Dean RA. From genes to genomes: a new paradigm for studying fungal pathogenesis in Magnaporthe oryzae. ADVANCES IN GENETICS 2007; 57:175-218. [PMID: 17352905 DOI: 10.1016/s0065-2660(06)57005-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Magnaporthe oryzae is the most destructive fungal pathogen of rice worldwide and because of its amenability to classical and molecular genetic manipulation, availability of a genome sequence, and other resources it has emerged as a leading model system to study host-pathogen interactions. This chapter reviews recent progress toward elucidation of the molecular basis of infection-related morphogenesis, host penetration, invasive growth, and host-pathogen interactions. Related information on genome analysis and genomic studies of plant infection processes is summarized under specific topics where appropriate. Particular emphasis is placed on the role of MAP kinase and cAMP signal transduction pathways and unique features in the genome such as repetitive sequences and expanded gene families. Emerging developments in functional genome analysis through large-scale insertional mutagenesis and gene expression profiling are detailed. The chapter concludes with new prospects in the area of systems biology, such as protein expression profiling, and highlighting remaining crucial information needed to fully appreciate host-pathogen interactions.
Collapse
Affiliation(s)
- Jin-Rong Xu
- Department of Botany and Plant Pathology, Purdue University West Lafayette, Indiana 47907, USA
| | | | | |
Collapse
|
43
|
Fuchs U, Hause G, Schuchardt I, Steinberg G. Endocytosis is essential for pathogenic development in the corn smut fungus Ustilago maydis. THE PLANT CELL 2006; 18:2066-81. [PMID: 16798890 PMCID: PMC1533974 DOI: 10.1105/tpc.105.039388] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2005] [Revised: 05/11/2006] [Accepted: 05/23/2006] [Indexed: 05/10/2023]
Abstract
It is well established that polarized exocytosis is essential for fungal virulence. By contrast, the contribution of endocytosis is unknown. We made use of a temperature-sensitive mutant in the endosomal target soluble N-ethylmaleimide-sensitive factor attachment protein receptor Yup1 and demonstrate that endocytosis in Ustilago maydis is essential for the initial steps of pathogenic development, including pheromone perception and cell-cell fusion. Furthermore, spore formation and germination were drastically reduced, whereas colonization of the plant was only slightly inhibited. The function of endocytosis in the recognition of mating pheromone through the G protein-coupled pheromone receptor Pra1 was analyzed in greater detail. Biologically active Pra1-green fluorescent protein localizes to the plasma membrane and is constitutively endocytosed. Yup1(ts) mutants that are blocked in the fusion of endocytic transport vesicles with early endosomes are impaired in pheromone perception and conjugation hyphae formation. This is attributable to an accumulation of Pra1-carrying endocytic vesicles in the cytoplasm and the depletion of the receptor from the membrane. Consistently, strong Pra1 expression rescues the signaling defects in endocytosis mutants, but subsequent cell fusion is still impaired. Thus, we conclude that endocytosis is essential for recognition of the partner at the beginning of the pathogenic program but has additional roles in mating as well as spore formation and germination.
Collapse
Affiliation(s)
- Uta Fuchs
- Max-Planck-Institut für Terrestrische Mikrobiologie, D-35043 Marburg, Germany
| | | | | | | |
Collapse
|
44
|
Barbosa AC, do Carmo AE, Graf L, Tomaz R, de Souza CF, Mendes J, Randi MAF, Buchi D, Schadeck RJG. Morphology and lipid body and vacuole dynamics during secondary conidia formation in Colletotrichum acutatum: laser scanning confocal analysis. Can J Microbiol 2006; 52:117-24. [PMID: 16541147 DOI: 10.1139/w05-104] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Colletotrichum acutatum may develop one or more secondary conidia after conidial germination and before mycelial growth. Secondary conidia formation and germination were influenced by conidia concentration. Concentrations greater than 1x105 conidia/mL were associated with germination decrease and with secondary conidia emergence. Secondary conidia can form either alone or simultaneously with germ tubes and appressoria. Confocal analysis showed numerous lipid bodies stored inside ungerminated conidia, which diminished during germ tube and appressoria formation, with or without secondary conidia formation. They were also reduced during secondary conidia formation alone. While there was a decrease inside germinated conidia, lipid bodies appeared inside secondary conidia since the initial stages. Intense vacuolization inside primary germinated conidia occurred at the same time as the decrease in lipid bodies, which were internalized and digested by vacuoles. During these events, small acidic vesicles inside secondary conidia were formed. Considering that the conidia were maintained in distilled water, with no exogenous nutrients, it is clear that ungerminated conidia contain enough stored lipids to form germ tubes, appressoria, and the additional secondary conidia replete with lipid reserves. These results suggested a very complex and well-balanced regulation that makes possible the catabolic and anabolic pathways of these lipid bodies.
Collapse
|
45
|
Peñalva MA. Tracing the endocytic pathway of Aspergillus nidulans with FM4-64. Fungal Genet Biol 2005; 42:963-75. [PMID: 16291501 DOI: 10.1016/j.fgb.2005.09.004] [Citation(s) in RCA: 170] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2005] [Revised: 09/11/2005] [Accepted: 09/15/2005] [Indexed: 10/25/2022]
Abstract
Simple procedures using FM4-64 to follow membrane internalization and transport to the vacuolar system and endomembranes in Aspergillus nidulans are described. FM4-64 internalization is energy, temperature and F-actin dependent, strongly suggesting that it occurs by endocytosis. The dye sequentially labels: (i) cortical punctuate organelles whose motility resembles that of yeast actin patches; (ii) approximately 0.7 microm circular, hollow structures representing mature endosome/vacuole; and (iii) intermediate and large (2-3 microm in diameter) size vacuoles whose lumen is strongly labeled with 5-(and-6)-carboxy-2',7'-dichlorofluorescein diacetate (CDCFDA). These large vacuoles possibly correspond to the final stage of one branch of the endocytic pathway. In addition, FM4-64 labels strongly the mitochondrial network and weakly the nuclear membrane. A class of cytoplasmic punctuate organelles which become fluorescent very shortly after dye loading and that can move in either apical or basal direction at an average rate of 2-3 microm s(-1) is also described. This work provides a useful framework for the phenotypic characterization of A. nidulans mutants affected in endocytosis.
Collapse
Affiliation(s)
- Miguel A Peñalva
- Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, Madrid 28040, Spain.
| |
Collapse
|
46
|
Fuchs U, Steinberg G. Endocytosis in the plant-pathogenic fungus Ustilago maydis. PROTOPLASMA 2005; 226:75-80. [PMID: 16231103 DOI: 10.1007/s00709-005-0109-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Accepted: 03/30/2005] [Indexed: 05/04/2023]
Abstract
Filamentous fungi are an important group of tip-growing organisms, which include numerous plant pathogens such as Magnaporthe grisea and Ustilago maydis. Despite their ecological and economical relevance, we are just beginning to unravel the importance of endocytosis in filamentous fungi. Most evidence for endocytosis in filamentous fungi is based on the use of endocytic tracer dyes that are taken up into the cell and delivered to the vacuole. Moreover, genomewide screening for candidate genes in Neurospora crassa and U. maydis confirmed the presence of most components of the endocytic machinery, indicating that endocytosis participates in filamentous growth. Indeed, it was shown that in U. maydis early endosomes cluster at sites of growth, where they support morphogenesis and polar growth, most likely via endosome-based membrane recycling. In humans, such recycling processes to the plasma membrane involve small GTPases such as Rab4. A homologue of this protein is encoded in the genome of U. maydis but is absent from the yeast Saccharomyces cerevisiae, suggesting that Rab4-mediated recycling is important for filamentous growth. Furthermore, human Rab4 regulates traffic of early endosomes along microtubules, and a similar microtubule-based transport is described for U. maydis. These observations suggest that Rab4-like GTPases might regulate endosome- and microtubule-based recycling during tip growth of filamentous fungi.
Collapse
Affiliation(s)
- U Fuchs
- Max-Planck-Institut für terrestrische Mikrobiologie, Marburg, Federal Republic of Germany
| | | |
Collapse
|
47
|
Chitarra GS, Breeuwer P, Rombouts FM, Abee T, Dijksterhuis J. Differentiation inside multicelled macroconidia of Fusarium culmorum during early germination. Fungal Genet Biol 2005; 42:694-703. [PMID: 15914044 DOI: 10.1016/j.fgb.2005.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2003] [Revised: 07/21/2004] [Accepted: 04/01/2005] [Indexed: 11/28/2022]
Abstract
Multicelled conidia are formed by many fungal species, but germination of these spores is scarcely studied. Here, the germination and the effects of antimicrobials on multicompartment macroconidia of Fusarium culmorum were investigated. Germ-tube formation was mostly from apical compartments. The intracellular pH (pH(in)) of the different individual cells of the macroconidia was monitored during germination. The pH(in) varied among different compartments and during different stages of germination. The internal pH was lowest in ungerminated cells and rose during germ-tube formation and was highest in new germ tubes. Antifungal compounds affect the pH(in) and differentiation of the conidia. The pH(in) inside the macroconidial compartments was lowered very fast in the presence of nystatin (1 and 4 microg/ml). At sublethal doses (0.3 microg/ml), the apical compartments were preferentially targeted showing lower pH(in) values. The reduced germination capacity of apical compartments under these conditions was compensated by an increased germination capacity of middle compartments.
Collapse
Affiliation(s)
- Gilma S Chitarra
- Laboratory of Food Microbiology,Wageningen University, Biotechnion, P.O. Box 8129, 6703 HD, Wageningen, The Netherlands
| | | | | | | | | |
Collapse
|
48
|
Czymmek K. Exploring Fungal Activity with Confocal and Multiphoton Microscopy. Mycology 2005. [DOI: 10.1201/9781420027891.ch15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|
49
|
Oberparleiter C, Kaiserer L, Haas H, Ladurner P, Andratsch M, Marx F. Active internalization of the Penicillium chrysogenum antifungal protein PAF in sensitive aspergilli. Antimicrob Agents Chemother 2004; 47:3598-601. [PMID: 14576124 PMCID: PMC253792 DOI: 10.1128/aac.47.11.3598-3601.2003] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Penicillium chrysogenum antifungal protein PAF inhibits the growth of various filamentous fungi. In this study, PAF was found to localize to the cytoplasm of sensitive aspergilli by indirect immunofluorescence staining. The internalization process required active metabolism and ATP and was prevented by latrunculin B, suggesting an endocytotic mechanism.
Collapse
|
50
|
Hickey PC, Swift SR, Roca M, Read ND. Live-cell Imaging of Filamentous Fungi Using Vital Fluorescent Dyes and Confocal Microscopy. METHODS IN MICROBIOLOGY 2004. [DOI: 10.1016/s0580-9517(04)34003-1] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
|