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Blanco CM, de Souza HADS, Martins PDC, Almeida-Silva J, Suarez-Fontes AM, Chaves YO, Vannier-Santos MA, Pratt-Riccio LR, Daniel-Ribeiro CT, Lopes SCP, Totino PRR. Cell Death of P. vivax Blood Stages Occurs in Absence of Classical Apoptotic Events and Induces Eryptosis of Parasitized Host Cells. Pathogens 2024; 13:673. [PMID: 39204273 PMCID: PMC11357032 DOI: 10.3390/pathogens13080673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Revised: 07/28/2024] [Accepted: 08/06/2024] [Indexed: 09/03/2024] Open
Abstract
Elucidation of pathways regulating parasite cell death is believed to contribute to identification of novel therapeutic targets for protozoan diseases, and in this context, apoptosis-like cell death has been reported in different groups of protozoa, in which metacaspases seem to play a role. In the genus Plasmodium, apoptotic markers have been detected in P. falciparum and P. berghei, and no study focusing on P. vivax cell death has been reported so far. In the present study, we investigated the susceptibility of P. vivax to undergo apoptotic cell death after incubating mature trophozoites with the classical apoptosis inducer staurosporine. As assessed by flow cytometry assays, staurosporine inhibited parasite intraerythrocytic development, which was accompanied by a decrease in cell viability, evidenced by reduced plasmodial mitochondrial activity. However, typical signs of apoptosis, such as DNA fragmentation, chromatin condensation, and nuclear segregation, were not detected in the parasites induced to cell death, and no significant alteration in metacaspase gene expression (PvMCA1) was observed under cell death stimulus. Interestingly, dying parasites positively modulated cell death (eryptosis) of host erythrocytes, which was marked by externalization of phosphatidylserine and cell shrinkage. Our study shows for the time that P. vivax blood stages may not be susceptible to apoptosis-like processes, while they could trigger eryptosis of parasitized cells by undergoing cell death. Further studies are required to elucidate the cellular machinery involved in cell death of P. vivax parasites as well as in the modulation of host cell death.
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Affiliation(s)
- Carolina Moreira Blanco
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz & Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro 21040-360, Brazil; (C.M.B.); (H.A.d.S.d.S.); (P.d.C.M.); (L.R.P.-R.); (C.T.D.-R.)
| | - Hugo Amorim dos Santos de Souza
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz & Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro 21040-360, Brazil; (C.M.B.); (H.A.d.S.d.S.); (P.d.C.M.); (L.R.P.-R.); (C.T.D.-R.)
| | - Priscilla da Costa Martins
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz & Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro 21040-360, Brazil; (C.M.B.); (H.A.d.S.d.S.); (P.d.C.M.); (L.R.P.-R.); (C.T.D.-R.)
| | - Juliana Almeida-Silva
- Laboratório de Inovações em Terapia, Ensino e Bioprodutos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21040-360, Brazil; (J.A.-S.); (M.A.V.-S.)
| | - Ana Marcia Suarez-Fontes
- Laboratório de Inovações em Terapia, Ensino e Bioprodutos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21040-360, Brazil; (J.A.-S.); (M.A.V.-S.)
| | - Yury Oliveira Chaves
- Instituto Leônidas e Maria Deane, Fiocruz Amazônia, Manaus 69057-070, Brazil; (Y.O.C.); (S.C.P.L.)
| | - Marcos André Vannier-Santos
- Laboratório de Inovações em Terapia, Ensino e Bioprodutos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21040-360, Brazil; (J.A.-S.); (M.A.V.-S.)
| | - Lilian Rose Pratt-Riccio
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz & Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro 21040-360, Brazil; (C.M.B.); (H.A.d.S.d.S.); (P.d.C.M.); (L.R.P.-R.); (C.T.D.-R.)
| | - Cláudio Tadeu Daniel-Ribeiro
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz & Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro 21040-360, Brazil; (C.M.B.); (H.A.d.S.d.S.); (P.d.C.M.); (L.R.P.-R.); (C.T.D.-R.)
| | - Stefanie Costa Pinto Lopes
- Instituto Leônidas e Maria Deane, Fiocruz Amazônia, Manaus 69057-070, Brazil; (Y.O.C.); (S.C.P.L.)
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD), Manaus 69040-000, Brazil
| | - Paulo Renato Rivas Totino
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz & Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro 21040-360, Brazil; (C.M.B.); (H.A.d.S.d.S.); (P.d.C.M.); (L.R.P.-R.); (C.T.D.-R.)
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Wang D, An B, Luo H, He C, Wang Q. Roles of CgEde1 and CgMca in Development and Virulence of Colletotrichum gloeosporioides. Int J Mol Sci 2024; 25:2943. [PMID: 38474190 DOI: 10.3390/ijms25052943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 02/28/2024] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
Anthracnose, induced by Colletotrichum gloeosporioides, poses a substantial economic threat to rubber tree yields and various other tropical crops. Ede1, an endocytic scaffolding protein, plays a crucial role in endocytic site initiation and maturation in yeast. Metacaspases, sharing structural similarities with caspase family proteases, are essential for maintaining cell fitness. To enhance our understanding of the growth and virulence of C. gloeosporioides, we identified a homologue of Ede1 (CgEde1) in C. gloeosporioides. The knockout of CgEde1 led to impairments in vegetative growth, conidiation, and pathogenicity. Furthermore, we characterized a weakly interacted partner of CgEde1 and CgMca (orthologue of metacaspase). Notably, both the single mutant ΔCgMca and the double mutant ΔCgEde1/ΔCgMca exhibited severe defects in conidiation and germination. Polarity establishment and pathogenicity were also disrupted in these mutants. Moreover, a significantly insoluble protein accumulation was observed in ΔCgMca and ΔCgEde1/ΔCgMca strains. These findings elucidate the mechanism by which CgEde1 and CgMca regulates the growth and pathogenicity of C. gloeosporioides. Their regulation involves influencing conidiation, polarity establishment, and maintaining cell fitness, providing valuable insights into the intricate interplay between CgEde1 and CgMca in C. gloeosporioides.
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Affiliation(s)
- Dan Wang
- Sanya Nanfan Research Institute of Hainan University, School of Tropical Agriculture and Forestry, Hainan University, Sanya 572025, China
| | - Bang An
- Sanya Nanfan Research Institute of Hainan University, School of Tropical Agriculture and Forestry, Hainan University, Sanya 572025, China
- Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China
| | - Hongli Luo
- Sanya Nanfan Research Institute of Hainan University, School of Tropical Agriculture and Forestry, Hainan University, Sanya 572025, China
- Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China
| | - Chaozu He
- Sanya Nanfan Research Institute of Hainan University, School of Tropical Agriculture and Forestry, Hainan University, Sanya 572025, China
- Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China
| | - Qiannan Wang
- Sanya Nanfan Research Institute of Hainan University, School of Tropical Agriculture and Forestry, Hainan University, Sanya 572025, China
- Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China
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3
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Eskandari E, Negri GL, Tan S, MacAldaz ME, Ding S, Long J, Nielsen K, Spencer SE, Morin GB, Eaves CJ. Dependence of human cell survival and proliferation on the CASP3 prodomain. Cell Death Discov 2024; 10:63. [PMID: 38321033 PMCID: PMC10847432 DOI: 10.1038/s41420-024-01826-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/11/2024] [Accepted: 01/17/2024] [Indexed: 02/08/2024] Open
Abstract
Mechanisms that regulate cell survival and proliferation are important for both the development and homeostasis of normal tissue, and as well as for the emergence and expansion of malignant cell populations. Caspase-3 (CASP3) has long been recognized for its proteolytic role in orchestrating cell death-initiated pathways and related processes; however, whether CASP3 has other functions in mammalian cells that do not depend on its known catalytic activity have remained unknown. To investigate this possibility, we examined the biological and molecular consequences of reducing CASP3 levels in normal and transformed human cells using lentiviral-mediated short hairpin-based knockdown experiments in combination with approaches designed to test the potential rescue capability of different components of the CASP3 protein. The results showed that a ≥50% reduction in CASP3 levels rapidly and consistently arrested cell cycle progression and survival in all cell types tested. Mass spectrometry-based proteomic analyses and more specific flow cytometric measurements strongly implicated CASP3 as playing an essential role in regulating intracellular protein aggregate clearance. Intriguingly, the rescue experiments utilizing different forms of the CASP3 protein showed its prosurvival function and effective removal of protein aggregates did not require its well-known catalytic capability, and pinpointed the N-terminal prodomain of CASP3 as the exclusive component needed in a diversity of human cell types. These findings identify a new mechanism that regulates human cell survival and proliferation and thus expands the complexity of how these processes can be controlled. The graphical abstract illustrates the critical role of CASP3 for sustained proliferation and survival of human cells through the clearance of protein aggregates.
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Affiliation(s)
- Ebrahim Eskandari
- Terry Fox Laboratory, British Columbia Cancer Research Institute, Vancouver, BC, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Gian Luca Negri
- Canada's Michael Smith Genome Sciences Centre, BC Cancer Research Institute, University of British Columbia, Vancouver, BC, Canada
| | - Susanna Tan
- Terry Fox Laboratory, British Columbia Cancer Research Institute, Vancouver, BC, Canada
| | - Margarita E MacAldaz
- Terry Fox Laboratory, British Columbia Cancer Research Institute, Vancouver, BC, Canada
| | - Shengsen Ding
- Terry Fox Laboratory, British Columbia Cancer Research Institute, Vancouver, BC, Canada
| | - Justin Long
- Terry Fox Laboratory, British Columbia Cancer Research Institute, Vancouver, BC, Canada
| | - Karina Nielsen
- Canada's Michael Smith Genome Sciences Centre, BC Cancer Research Institute, University of British Columbia, Vancouver, BC, Canada
| | - Sandra E Spencer
- Canada's Michael Smith Genome Sciences Centre, BC Cancer Research Institute, University of British Columbia, Vancouver, BC, Canada
| | - Gregg B Morin
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
- Canada's Michael Smith Genome Sciences Centre, BC Cancer Research Institute, University of British Columbia, Vancouver, BC, Canada
| | - Connie J Eaves
- Terry Fox Laboratory, British Columbia Cancer Research Institute, Vancouver, BC, Canada.
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada.
- School of Biomedical Engineering, University of British Columbia, Vancouver, BC, Canada.
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Wang G, Wang Y, Wang K, Zhao H, Liu M, Liang W, Li D. Perillaldehyde Functions as a Potential Antifungal Agent by Triggering Metacaspase-Independent Apoptosis in Botrytis cinerea. Microbiol Spectr 2023; 11:e0052623. [PMID: 37191530 PMCID: PMC10269628 DOI: 10.1128/spectrum.00526-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 04/20/2023] [Indexed: 05/17/2023] Open
Abstract
Botrytis cinerea, the causal agent of gray mold, is an important plant pathogen causing preharvest and postharvest diseases. Due to the extensive use of commercial fungicides, fungicide-resistant strains have emerged. Natural compounds with antifungal properties are widely present in various kinds of organisms. Perillaldehyde (PA), derived from the plant species Perilla frutescens, is generally recognized as a potent antimicrobial substance and to be safe to humans and the environment. In this study, we demonstrated that PA could significantly inhibit the mycelial growth of B. cinerea and reduced its pathogenicity on tomato leaves. We also found that PA had a significant protective effect on tomato, grape, and strawberry. The antifungal mechanism of PA was investigated by measuring the reactive oxygen species (ROS) accumulation, the intracellular Ca2+ level, the mitochondrial membrane potential, DNA fragmentation, and phosphatidylserine exposure. Further analyses revealed that PA promoted protein ubiquitination and induced autophagic activities and then triggered protein degradation. When the two metacaspase genes, BcMca1 and BcMca2, were knocked out from B. cinerea, all mutants did not exhibit reduced sensitivity to PA. These findings demonstrated that PA could induce metacaspase-independent apoptosis in B. cinerea. Based on our results, we proposed that PA could be used as an effective control agent for gray mold management. IMPORTANCE Botrytis cinerea causes gray mold disease, is considered one of the most important dangerous pathogens worldwide, and leads to severe economic losses worldwide. Due to the lack of resistant varieties of B. cinerea, gray mold control has mainly relied on application of synthetic fungicides. However, long-term and extensive use of synthetic fungicides has increased fungicide resistance in B. cinerea and is harmful to humans and the environment. In this study, we found that perillaldehyde has a significant protective effect on tomato, grape, and strawberry. We further characterized the antifungal mechanism of PA on B. cinerea. Our results indicated that PA induced apoptosis that was independent of metacaspase function.
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Affiliation(s)
- Guanbo Wang
- Shandong Engineering Research Center for Environment-Friendly Agricultural Pest Management, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
| | - Yadi Wang
- Shandong Engineering Research Center for Environment-Friendly Agricultural Pest Management, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
| | - Kunchun Wang
- The Linzi Center for Agricultural and Rural Development, Zibo, China
| | - Haonan Zhao
- Shandong Engineering Research Center for Environment-Friendly Agricultural Pest Management, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
| | - Mengjie Liu
- Shandong Engineering Research Center for Environment-Friendly Agricultural Pest Management, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
| | - Wenxing Liang
- Shandong Engineering Research Center for Environment-Friendly Agricultural Pest Management, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
| | - Delong Li
- Shandong Engineering Research Center for Environment-Friendly Agricultural Pest Management, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
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Kavya N, Prasannakumar MK, Venkateshbabu G, Niranjan V, Uttarkar A, Buela Parivallal P, Banakar SN, Mahesh HB, Devanna P, Manasa KG, Shivakumara TN. Insights on Novel Effectors and Characterization of Metacaspase (RS107_6) as a Potential Cell Death-Inducing Protein in Rhizoctonia solani. Microorganisms 2023; 11:microorganisms11040920. [PMID: 37110343 PMCID: PMC10143347 DOI: 10.3390/microorganisms11040920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 03/27/2023] [Accepted: 03/29/2023] [Indexed: 04/05/2023] Open
Abstract
Effectors play an important role in host–pathogen interactions. Though an economically significant disease in rice, knowledge regarding the infection strategy of Rhizoctonia solani is obscure. In this study, we performed a genome-wide identification of the effectors in R. solani based on the characteristics of previously reported effector proteins. A total of seven novel effectors (designated as RS107_1 to RS107_7) in the disease mechanism of R. solani were identified and were predicted to be non-classically secreted proteins with functionally conserved domains. The function, reactivity, and stability of these proteins were evaluated through physiochemical characterization. The target proteins involved in the regulation of rice defense mechanisms were identified. Furthermore, the effector genes were cloned and RS107_6 (metacaspase) was heterologously expressed in Escherichia coli to obtain a purified protein of ~36.5 kDa. The MALD-TOF characterization confirmed that the protein belonged to a metacaspase of the Peptidase_C14 protein family, 906 bp in size, and encoded a polypeptide of 301 amino acids. These findings suggest that the identified effectors can potentially serve as a virulence factor and can be targeted for the management of sheath blight in rice.
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Affiliation(s)
- N. Kavya
- PathoGenomics Laboratory, Department of Plant Pathology, Gandhi Krishi Vignana Kendra (GKVK), University of Agricultural Sciences, Bangalore 560065, Karnataka, India
| | - M. K. Prasannakumar
- PathoGenomics Laboratory, Department of Plant Pathology, Gandhi Krishi Vignana Kendra (GKVK), University of Agricultural Sciences, Bangalore 560065, Karnataka, India
| | - Gopal Venkateshbabu
- PathoGenomics Laboratory, Department of Plant Pathology, Gandhi Krishi Vignana Kendra (GKVK), University of Agricultural Sciences, Bangalore 560065, Karnataka, India
| | - Vidya Niranjan
- Department of Biotechnology, RV College of Engineering, Bangalore 560059, Karnataka, India
| | - Akshay Uttarkar
- Department of Biotechnology, RV College of Engineering, Bangalore 560059, Karnataka, India
| | - P. Buela Parivallal
- PathoGenomics Laboratory, Department of Plant Pathology, Gandhi Krishi Vignana Kendra (GKVK), University of Agricultural Sciences, Bangalore 560065, Karnataka, India
| | - Sahana N. Banakar
- PathoGenomics Laboratory, Department of Plant Pathology, Gandhi Krishi Vignana Kendra (GKVK), University of Agricultural Sciences, Bangalore 560065, Karnataka, India
| | - H. B. Mahesh
- Department of Genetics and Plant Breeding, Gandhi Krishi Vignana Kendra (GKVK), University of Agricultural Sciences, Bangalore 560065, Karnataka, India
| | - Pramesh Devanna
- Rice Pathology Laboratory, All India Coordinated Rice Improvement Programme, Gangavathi, University of Agricultural Sciences, Raichur 584104, Karnataka, India
| | - K. G. Manasa
- PathoGenomics Laboratory, Department of Plant Pathology, Gandhi Krishi Vignana Kendra (GKVK), University of Agricultural Sciences, Bangalore 560065, Karnataka, India
| | - Tagginahalli N. Shivakumara
- PathoGenomics Laboratory, Department of Plant Pathology, Gandhi Krishi Vignana Kendra (GKVK), University of Agricultural Sciences, Bangalore 560065, Karnataka, India
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Mukherjee S, Bhakta K, Ghosh A, Ghosh A. Ger1 is a secreted aspartic acid protease essential for spore germination in Ustilago maydis. Yeast 2023; 40:102-116. [PMID: 36562128 DOI: 10.1002/yea.3835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 12/19/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022] Open
Abstract
Ustilago maydis expresses a number of proteases during its pathogenic lifecycle. Some of the proteases including both intracellular and extracellular ones have previously been shown to influence the virulence of the pathogen. However, any role of secreted proteases in the sporulation process of U. maydis have not been explored earlier. In this study we have investigated the biological function of one such secreted protease, Ger1 belonging to aspartic protease A1 family. An assessment of the real time expression of ger1 revealed an infection specific expression of the protein especially during late phases of infection. We also evaluated any contribution of the protein in the pathogenicity of the fungus. Our data revealed an involvement of Ger1 in the sporulation and spore germination processes of U. maydis. Ger1 also showed positive influence on the pathogenicity of the fungus and accordingly the ger1 deletion mutant exhibited reduced pathogenicity. The study also demonstrated the protease activity associated with Ger1 to be essential for its biological function. Fluorescence microscopy of maize plants infected with U. maydis cells expressing Ger1-mcherry-HA also revealed that Ger1 is efficiently secreted within maize apoplast.
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Affiliation(s)
| | - Koustav Bhakta
- Department of Biochemistry, Bose Institute, Kolkata, India
| | | | - Anupama Ghosh
- Division of Plant Biology, Bose Institute, Kolkata, India
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Garcia N, Kalicharan RE, Kinch L, Fernandez J. Regulating Death and Disease: Exploring the Roles of Metacaspases in Plants and Fungi. Int J Mol Sci 2022; 24:ijms24010312. [PMID: 36613753 PMCID: PMC9820594 DOI: 10.3390/ijms24010312] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 12/20/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022] Open
Abstract
Identified over twenty years ago and distantly related to animal caspases are a group of cysteine proteases known as metacaspases. Throughout the years, much like caspase roles in metazoans, metacaspases have been shown to be involved in regulating cellular death in non-metazoan organisms. Yet, continued research on metacaspases describes these proteins as intricate and multifunctional, displaying striking diversity on distinct biological functions. In this review, we intend to describe the recent advances in our understanding of the divergence of metacaspase functionality in plants and fungi. We will dissect the duality of metacaspase activity in the context of plant-pathogen interactions, providing a unique lens from which to characterize metacaspases in the development, immunity, and stress responses of plants, and the development and virulence of fungi. Furthermore, we explore the evolutionary trajectory of fungal metacaspases to delineate their structure and function. Bridging the gap between metacaspase roles in immunity and pathogenicity of plant-pathogen interactions can enable more effective and targeted phytopathogen control efforts to increase production of globally important food crops. Therefore, the exploitation and manipulation of metacaspases in plants or fungi represent new potential avenues for developing mitigation strategies against plant pathogens.
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Affiliation(s)
- Nalleli Garcia
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
| | - Rachel E. Kalicharan
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
| | - Lisa Kinch
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jessie Fernandez
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
- Correspondence:
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Rico-Ramírez AM, Pedro Gonçalves A, Louise Glass N. Fungal Cell Death: The Beginning of the End. Fungal Genet Biol 2022; 159:103671. [PMID: 35150840 DOI: 10.1016/j.fgb.2022.103671] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/04/2022] [Accepted: 01/29/2022] [Indexed: 11/04/2022]
Abstract
Death is an important part of an organism's existence and also marks the end of life. On a cellular level, death involves the execution of complex processes, which can be classified into different types depending on their characteristics. Despite their "simple" lifestyle, fungi carry out highly specialized and sophisticated mechanisms to regulate the way their cells die, and the pathways underlying these mechanisms are comparable with those of plants and metazoans. This review focuses on regulated cell death in fungi and discusses the evidence for the occurrence of apoptotic-like, necroptosis-like, pyroptosis-like death, and the role of the NLR proteins in fungal cell death. We also describe recent data on meiotic drive elements involved in "spore killing" and the molecular basis of allorecognition-related cell death during cell fusion of genetically dissimilar cells. Finally, we discuss how fungal regulated cell death can be relevant in developing strategies to avoid resistance and tolerance to antifungal agents.
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Affiliation(s)
- Adriana M Rico-Ramírez
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720
| | - A Pedro Gonçalves
- Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan City, 701, Taiwan
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720.
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9
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Soberanes-Gutiérrez CV, León-Ramírez C, Sánchez-Segura L, Cordero-Martínez E, Vega-Arreguín JC, Ruiz-Herrera J. Cell death in Ustilago maydis: comparison with other fungi and the effect of metformin and curcumin on its chronological lifespan. FEMS Yeast Res 2021; 20:5908381. [PMID: 32945857 DOI: 10.1093/femsyr/foaa051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Accepted: 09/14/2020] [Indexed: 12/11/2022] Open
Abstract
Ustilago maydis is a Basidiomycota fungus, in which very little is known about its mechanisms of cell survival and death. To date, only the role of metacaspase1, acetate and hydrogen peroxide as inducers of cell death has been investigated. In the present work, we analyzed the lifespan of U. maydis compared with other species like Sporisorium reilianum, Saccharomyces cerevisiae and Yarrowia lipolytica, and we observed that U. maydis has a minor lifespan. We probe the addition of low concentrations metformin and curcumin to the culture media, and we observed that both prolonged the lifespan of U. maydis, a result observed for the first time in a phytopathogen fungus. However, higher concentrations of curcumin were toxic for the cells, and interestingly induced the yeast-to-mycelium dimorphic transition. The positive effect of metformin and curcumin appears to be related to an inhibition of the mechanistic Target of Rapamycin (mTOR) pathway, increase expression of autophagy genes and reducing of reactive oxygen species. These data indicate that U. maydis may be a eukaryotic model organism to elucidate the molecular mechanism underlying apoptotic and necrosis pathways, and the lifespan increase caused by metformin and curcumin.
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Affiliation(s)
- Cinthia V Soberanes-Gutiérrez
- Laboratorio de Ciencias Agrogenómicas, de la Escuela Nacional de Estudios Superiores Unidad León, Universidad Nacional Autónoma de México, Blv. UNAM 2011, Col. Predio el Saucillo y El Potrero, Comunidad de Los Tepetates, 37684, León Gto., México.,Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Km. 9.6 Libramiento Norte Carr. Irapuato-León 36824 Irapuato Gto., México
| | - Claudia León-Ramírez
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Km. 9.6 Libramiento Norte Carr. Irapuato-León 36824 Irapuato Gto., México
| | - Lino Sánchez-Segura
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Km. 9.6 Libramiento Norte Carr. Irapuato-León 36824 Irapuato Gto., México
| | - Emmanuel Cordero-Martínez
- Laboratorio de Ciencias Agrogenómicas, de la Escuela Nacional de Estudios Superiores Unidad León, Universidad Nacional Autónoma de México, Blv. UNAM 2011, Col. Predio el Saucillo y El Potrero, Comunidad de Los Tepetates, 37684, León Gto., México
| | - Julio C Vega-Arreguín
- Laboratorio de Ciencias Agrogenómicas, de la Escuela Nacional de Estudios Superiores Unidad León, Universidad Nacional Autónoma de México, Blv. UNAM 2011, Col. Predio el Saucillo y El Potrero, Comunidad de Los Tepetates, 37684, León Gto., México
| | - José Ruiz-Herrera
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Km. 9.6 Libramiento Norte Carr. Irapuato-León 36824 Irapuato Gto., México
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10
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Graff van Creveld S, Ben-Dor S, Mizrachi A, Alcolombri U, Hopes A, Mock T, Rosenwasser S, Vardi A. Biochemical Characterization of a Novel Redox-Regulated Metacaspase in a Marine Diatom. Front Microbiol 2021; 12:688199. [PMID: 34566902 PMCID: PMC8455989 DOI: 10.3389/fmicb.2021.688199] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 08/16/2021] [Indexed: 11/24/2022] Open
Abstract
Programmed cell death (PCD) in marine microalgae was suggested to be one of the mechanisms that facilitates bloom demise, yet its molecular components in phytoplankton are unknown. Phytoplankton are completely lacking any of the canonical components of PCD, such as caspases, but possess metacaspases. Metacaspases were shown to regulate PCD in plants and some protists, but their roles in algae and other organisms are still elusive. Here, we identified and biochemically characterized a type III metacaspase from the model diatom Phaeodactylum tricornutum, termed PtMCA-IIIc. Through expression of recombinant PtMCA-IIIc in E. coli, we revealed that PtMCA-IIIc exhibits a calcium-dependent protease activity, including auto-processing and cleavage after arginine. Similar metacaspase activity was detected in P. tricornutum cell extracts. PtMCA-IIIc overexpressing cells exhibited higher metacaspase activity, while CRISPR/Cas9-mediated knockout cells had decreased metacaspase activity compared to WT cells. Site-directed mutagenesis of cysteines that were predicted to form a disulfide bond decreased recombinant PtMCA-IIIc activity, suggesting its enhancement under oxidizing conditions. One of those cysteines was oxidized, detected in redox proteomics, specifically in response to lethal concentrations of hydrogen peroxide and a diatom derived aldehyde. Phylogenetic analysis revealed that this cysteine-pair is unique and widespread among diatom type III metacaspases. The characterization of a cell death associated protein in diatoms provides insights into the evolutionary origins of PCD and its ecological significance in algal bloom dynamics.
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Affiliation(s)
- Shiri Graff van Creveld
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
- School of Oceanography, University of Washington, Seattle, WA, United States
| | - Shifra Ben-Dor
- Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Avia Mizrachi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Uria Alcolombri
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
- Department of Civil, Environmental and Geomatic Engineering, Institute for Environmental Engineering, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Amanda Hopes
- School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
| | - Thomas Mock
- School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
| | - Shilo Rosenwasser
- Robert H. Smith Faculty of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Assaf Vardi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
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11
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Soberanes-Gutiérrez CV, Pérez-Rueda E, Ruíz-Herrera J, Galán-Vásquez E. Identifying Genes Devoted to the Cell Death Process in the Gene Regulatory Network of Ustilago maydis. Front Microbiol 2021; 12:680290. [PMID: 34093501 PMCID: PMC8175908 DOI: 10.3389/fmicb.2021.680290] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 04/30/2021] [Indexed: 01/26/2023] Open
Abstract
Cell death is a process that can be divided into three morphological patterns: apoptosis, autophagy and necrosis. In fungi, cell death is induced in response to intracellular and extracellular perturbations, such as plant defense molecules, toxins and fungicides, among others. Ustilago maydis is a dimorphic fungus used as a model for pathogenic fungi of animals, including humans, and plants. Here, we reconstructed the transcriptional regulatory network of U. maydis, through homology inferences by using as templates the well-known gene regulatory networks (GRNs) of Saccharomyces cerevisiae, Aspergillus nidulans and Neurospora crassa. Based on this GRN, we identified transcription factors (TFs) as hubs and functional modules and calculated diverse topological metrics. In addition, we analyzed exhaustively the module related to cell death, with 60 TFs and 108 genes, where diverse cell proliferation, mating-type switching and meiosis, among other functions, were identified. To determine the role of some of these genes, we selected a set of 11 genes for expression analysis by qRT-PCR (sin3, rlm1, aif1, tdh3 [isoform A], tdh3 [isoform B], ald4, mca1, nuc1, tor1, ras1, and atg8) whose homologues in other fungi have been described as central in cell death. These genes were identified as downregulated at 72 h, in agreement with the beginning of the cell death process. Our results can serve as the basis for the study of transcriptional regulation, not only of the cell death process but also of all the cellular processes of U. maydis.
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Affiliation(s)
- Cinthia V. Soberanes-Gutiérrez
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Mexico
- Laboratorio de Ciencias Agrogenómicas, de la Escuela Nacional de Estudios Superiores Unidad León, Universidad Nacional Autónoma de México, León, Mexico
| | - Ernesto Pérez-Rueda
- Unidad Académica Yucatán, Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, Mérida, Mexico
| | - José Ruíz-Herrera
- Laboratorio de Ciencias Agrogenómicas, de la Escuela Nacional de Estudios Superiores Unidad León, Universidad Nacional Autónoma de México, León, Mexico
| | - Edgardo Galán-Vásquez
- Departamento de Ingeniería de Sistemas Computacionales y Automatización, Instituto de Investigación en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México - Ciudad Universitaria, Mexico City, Mexico
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12
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Role of Two Metacaspases in Development and Pathogenicity of the Rice Blast Fungus Magnaporthe oryzae. mBio 2021; 12:mBio.03471-20. [PMID: 33563831 PMCID: PMC7885106 DOI: 10.1128/mbio.03471-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Magnaporthe oryzae causes rice blast disease that threatens global food security by resulting in the severe loss of rice production every year. A tightly regulated life cycle allows M. oryzae to disarm the host plant immune system during its biotrophic stage before triggering plant cell death in its necrotrophic stage. Rice blast disease caused by Magnaporthe oryzae is a devastating disease of cultivated rice worldwide. Infections by this fungus lead to a significant reduction in rice yields and threats to food security. To gain better insight into growth and cell death in M. oryzae during infection, we characterized two predicted M. oryzae metacaspase proteins, MoMca1 and MoMca2. These proteins appear to be functionally redundant and can complement the yeast Yca1 homologue. Biochemical analysis revealed that M. oryzae metacaspases exhibited Ca2+-dependent caspase activity in vitro. Deletion of both MoMca1 and MoMca2 in M. oryzae resulted in reduced sporulation, delay in conidial germination, and attenuation of disease severity. In addition, the double ΔMomca1mca2 mutant strain showed increased radial growth in the presence of oxidative stress. Interestingly, the ΔMomca1mca2 strain showed an increased accumulation of insoluble aggregates compared to the wild-type strain during vegetative growth. Our findings suggest that MoMca1 and MoMca2 promote the clearance of insoluble aggregates in M. oryzae, demonstrating the important role these metacaspases have in fungal protein homeostasis. Furthermore, these metacaspase proteins may play additional roles, like in regulating stress responses, that would help maintain the fitness of fungal cells required for host infection.
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13
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Luan QL, Zhu YX, Ma S, Sun Y, Liu XY, Liu M, Balint-Kurti PJ, Wang GF. Maize metacaspases modulate the defense response mediated by the NLR protein Rp1-D21 likely by affecting its subcellular localization. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:151-166. [PMID: 33107667 DOI: 10.1111/tpj.15047] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 09/03/2020] [Accepted: 09/15/2020] [Indexed: 05/22/2023]
Abstract
Plants usually employ resistance (R) genes to defend against the infection of pathogens, and most R genes encode intracellular nucleotide-binding, leucine-rich repeat (NLR) proteins. The recognition between R proteins and their cognate pathogens often triggers a rapid localized cell death at the pathogen infection sites, termed the hypersensitive response (HR). Metacaspases (MCs) belong to a cysteine protease family, structurally related to metazoan caspases. MCs play crucial roles in plant immunity. However, the underlying molecular mechanism and the link between MCs and NLR-mediated HR are not clear. In this study, we systematically investigated the MC gene family in maize and identified 11 ZmMCs belonging to two types. Further functional analysis showed that the type I ZmMC1 and ZmMC2, but not the type II ZmMC9, suppress the HR-inducing activity of the autoactive NLR protein Rp1-D21 and of its N-terminal coiled-coil (CCD21 ) signaling domain when transiently expressed in Nicotiana benthamiana. ZmMC1 and ZmMC2 physically associate with CCD21 in vivo. We further showed that ZmMC1 and ZmMC2, but not ZmMC9, are predominantly localized in a punctate distribution in both N. benthamiana and maize (Zea mays) protoplasts. Furthermore, the co-expression of ZmMC1 and ZmMC2 with Rp1-D21 and CCD21 causes their re-distribution from being uniformly distributed in the nucleocytoplasm to a punctate distribution co-localizing with ZmMC1 and ZmMC2. We reveal a novel role of plant MCs in modulating the NLR-mediated defense response and derive a model to explain it.
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Affiliation(s)
- Qing-Ling Luan
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, 266237, PR China
| | - Yu-Xiu Zhu
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, 266237, PR China
| | - Shijun Ma
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, 266237, PR China
| | - Yang Sun
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, 266237, PR China
| | - Xiao-Ying Liu
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, 266237, PR China
| | - Mengjie Liu
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, 266237, PR China
| | - Peter J Balint-Kurti
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, 27695, USA
- U.S. Department of Agriculture-Agricultural Research Service, Plant Science Research Unit, Raleigh, North Carolina, 27695, USA
| | - Guan-Feng Wang
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong, 266237, PR China
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14
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Kojic M, Milisavljevic M. When disaster strikes: Reconstitution of population density by expansion of survivors. Mol Ecol 2020; 29:4757-4764. [DOI: 10.1111/mec.15680] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/03/2020] [Accepted: 09/29/2020] [Indexed: 12/20/2022]
Affiliation(s)
- Milorad Kojic
- Institute of Molecular Genetics and Genetic Engineering University of Belgrade Beograd Serbia
| | - Mira Milisavljevic
- Institute of Molecular Genetics and Genetic Engineering University of Belgrade Beograd Serbia
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15
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Mukherjee D, Gupta S, Ghosh A, Ghosh A. Ustilago maydis secreted T2 ribonucleases, Nuc1 and Nuc2 scavenge extracellular RNA. Cell Microbiol 2020; 22:e13256. [PMID: 32844528 DOI: 10.1111/cmi.13256] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 08/18/2020] [Indexed: 12/22/2022]
Abstract
Ustilago maydis genome codes for many secreted ribonucleases. The contribution of two among these belonging to the T2 family (Nuc1 and Nuc2) in the pathogen virulence, has been assessed in this study. The nuc1 and nuc2 deletion mutants showed not only reduced pathogenicity compared to the SG200 WT strain but also exhibited significant delay in the completion of the pathogenic lifecycle. Both the proteins were also tested for their nucleolytic activities towards RNA substrates from maize and yeast. This also yielded valuable insights into the ability of the ribonucleases to utilise extracellular RNA as a nutrient source. Our study therefore established a role of two T2 type secreted ribonucleases of a phytopathogen in the acquisition of nutrient for the first time. This study also provides evidence that maize apoplast contains RNA, which can be utilised as a substrate by both Nuc1 and Nuc2.
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Affiliation(s)
- Dibya Mukherjee
- Division of Plant Biology, Bose Institute Centenary Campus, Kolkata, India
| | - Sayandeep Gupta
- Department of Biochemistry, Bose Institute Centenary Campus, Kolkata, India
| | - Abhrajyoti Ghosh
- Department of Biochemistry, Bose Institute Centenary Campus, Kolkata, India
| | - Anupama Ghosh
- Division of Plant Biology, Bose Institute Centenary Campus, Kolkata, India
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16
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Mukherjee D, Mitra A, Ghosh A. Detection of Apoptosis-like Cell Death in Ustilago maydis by Annexin V-FITC Staining. Bio Protoc 2018; 8:e2948. [PMID: 34395760 DOI: 10.21769/bioprotoc.2948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 07/10/2018] [Accepted: 07/15/2018] [Indexed: 11/02/2022] Open
Abstract
Programmed cell death (PCD) guides the transition between key developmental stages in many organisms. PCD also remains an important fate for many organisms upon exposure to different stress conditions. Therefore, an insight into the progression of PCD during the execution of a biological phenomenon can yield significant details of the underlying mechanism. Apoptosis, as well as apoptosis-like programmed cell death, constitutes one of the forms of PCD in higher and lower eukaryotes respectively. Flipping of phosphatidylserine (PS) from the inner leaflet of the plasma membrane to the outer leaflet is among the different hallmarks of apoptosis/apoptosis-like PCD that marks the initiation of the said cell death event. This flipping can be detected through staining of the target cells using annexin V-FITC that binds specifically to PS. In Ustilago maydis the staining of the externally exposed PS by annexin V-FITC is difficult due to the presence of cell wall. The key to such staining, therefore, relies on the gentle removal of the cell wall without significantly altering the underlying plasma membrane architecture/topology. This protocol highlights the dependence of the PS staining on the extent of protoplastation of the stressed cells in Ustilago maydis.
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Affiliation(s)
- Dibya Mukherjee
- Division of Plant Biology, Bose Institute, Centenary Campus, Kolkata, India
| | - Aroni Mitra
- Division of Plant Biology, Bose Institute, Centenary Campus, Kolkata, India
| | - Anupama Ghosh
- Division of Plant Biology, Bose Institute, Centenary Campus, Kolkata, India
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17
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Kretschmer M, Lambie S, Croll D, Kronstad JW. Acetate provokes mitochondrial stress and cell death in Ustilago maydis. Mol Microbiol 2018; 107:488-507. [PMID: 29235175 DOI: 10.1111/mmi.13894] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 12/06/2017] [Accepted: 12/08/2017] [Indexed: 12/30/2022]
Abstract
The fungal pathogen Ustilago maydis causes disease on maize by mating to establish an infectious filamentous cell type that invades the host and induces tumours. We previously found that β-oxidation mutants were defective in virulence and did not grow on acetate. Here, we demonstrate that acetate inhibits filamentation during mating and in response to oleic acid. We therefore examined the influence of different carbon sources by comparing the transcriptomes of cells grown on acetate, oleic acid or glucose, with expression changes for the fungus during tumour formation in planta. Guided by the transcriptional profiling, we found that acetate negatively influenced resistance to stress, promoted the formation of reactive oxygen species, triggered cell death in stationary phase and impaired virulence on maize. We also found that acetate induced mitochondrial stress by interfering with mitochondrial functions. Notably, the disruption of oxygen perception or inhibition of the electron transport chain also influenced filamentation and mating. Finally, we made use of the connections between acetate and β-oxidation to test metabolic inhibitors for an influence on growth and virulence. These experiments identified diclofenac as a potential inhibitor of virulence. Overall, these findings support the possibility of targeting mitochondrial metabolic functions to control fungal pathogens.
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Affiliation(s)
- Matthias Kretschmer
- Michael Smith Laboratories, Department of Microbiology and Immunology, and Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Scott Lambie
- Michael Smith Laboratories, Department of Microbiology and Immunology, and Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Daniel Croll
- Michael Smith Laboratories, Department of Microbiology and Immunology, and Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, CH-2000 Neuchâtel, Switzerland
| | - James W Kronstad
- Michael Smith Laboratories, Department of Microbiology and Immunology, and Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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