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Pu X, Lin A, Wang C, Jibril SM, Yang X, Yang K, Li C, Wang Y. MoHG1 Regulates Fungal Development and Virulence in Magnaporthe oryzae. J Fungi (Basel) 2024; 10:663. [PMID: 39330422 PMCID: PMC11433375 DOI: 10.3390/jof10090663] [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: 08/17/2024] [Revised: 09/18/2024] [Accepted: 09/18/2024] [Indexed: 09/28/2024] Open
Abstract
Magnaporthe oryzae causes rice blast disease, which threatens global rice production. The interaction between M. oryzae and rice is regarded as a classic model for studying the relationship between the pathogen and the host. In this study, we found a gene, MoHG1, regulating fungal development and virulence in M. oryzae. The ∆Mohg1 mutants showed more sensitivity to cell wall integrity stressors and their cell wall is more easily degraded by enzymes. Moreover, a decreased content of chitin but higher contents of arabinose, sorbitol, lactose, rhamnose, and xylitol were found in the ∆Mohg1 mutant. Combined with transcriptomic results, many genes in MAPK and sugar metabolism pathways are significantly regulated in the ∆Mohg1 mutant. A hexokinase gene, MGG_00623 was downregulated in ∆Mohg1, according to transcriptome results. We overexpressed MGG_00623 in a ∆Mohg1 mutant. The results showed that fungal growth and chitin contents in MGG_00623-overexpressing strains were restored significantly compared to the ∆Mohg1 mutant. Furthermore, MoHG1 could interact with MGG_00623 directly through the yeast two-hybrid and BiFC. Overall, these results suggest that MoHG1 coordinating with hexokinase regulates fungal development and virulence by affecting chitin contents and cell wall integrity in M. oryzae, which provides a reference for studying the functions of MoHG1-like genes.
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Affiliation(s)
- Xin Pu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Transboundary Pests, Yunnan Agricultural University, Kunming 650201, China
| | - Aijia Lin
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Transboundary Pests, Yunnan Agricultural University, Kunming 650201, China
| | - Chun Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Transboundary Pests, Yunnan Agricultural University, Kunming 650201, China
| | - Sauban Musa Jibril
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Transboundary Pests, Yunnan Agricultural University, Kunming 650201, China
| | - Xinyun Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Transboundary Pests, Yunnan Agricultural University, Kunming 650201, China
| | - Kexin Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Transboundary Pests, Yunnan Agricultural University, Kunming 650201, China
| | - Chengyun Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Transboundary Pests, Yunnan Agricultural University, Kunming 650201, China
| | - Yi Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Transboundary Pests, Yunnan Agricultural University, Kunming 650201, China
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Lu K, Chen R, Yang Y, Xu H, Jiang J, Li L. Involvement of the Cell Wall-Integrity Pathway in Signal Recognition, Cell-Wall Biosynthesis, and Virulence in Magnaporthe oryzae. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2023; 36:608-622. [PMID: 37140471 DOI: 10.1094/mpmi-11-22-0231-cr] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The fungal cell wall is the first layer exposed to the external environment. The cell wall has key roles in regulating cell functions, such as cellular stability, permeability, and protection against stress. Understanding the structure of the cell wall and the mechanism of its biogenesis is important for the study of fungi. Highly conserved in fungi, including Magnaporthe oryzae, the cell wall-integrity (CWI) pathway is the primary signaling cascade regulating cell-wall structure and function. The CWI pathway has been demonstrated to correlate with pathogenicity in many phytopathogenic fungi. In the synthesis of the cell wall, the CWI pathway cooperates with multiple signaling pathways to regulate cell morphogenesis and secondary metabolism. Many questions have arisen regarding the cooperation of different signaling pathways with the CWI pathway in regulating cell-wall synthesis and pathogenicity. In this review, we summarized the latest advances in the M. oryzae CWI pathway and cell-wall structure. We discussed the CWI pathway components and their involvement in different aspects, such as virulence factors, the possibility of the pathway as a target for antifungal therapies, and crosstalk with other signaling pathways. This information will aid in better understanding the universal functions of the CWI pathway in regulating cell-wall synthesis and pathogenicity in M. oryzae. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Kailun Lu
- School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China
| | - Rangrang Chen
- School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China
| | - Yi Yang
- School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China
| | - Hui Xu
- School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China
| | - Jihong Jiang
- School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China
| | - Lianwei Li
- School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
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Fu R, Wang J, Chen C, Liu Y, Zhao L, Lu D. Transcriptomic and Metabolomic Analyses Provide Insights into the Pathogenic Mechanism of the Rice False Smut Pathogen Ustilaginoidea virens. Int J Mol Sci 2023; 24:10805. [PMID: 37445981 DOI: 10.3390/ijms241310805] [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: 05/25/2023] [Revised: 06/18/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023] Open
Abstract
Rice false smut, caused by the fungal pathogen Ustilaginoidea virens, is a worldwide rice fungal disease. However, the molecular mechanism of the pathogenicity of the fungus U. virens remains unclear. To understand the molecular mechanism of pathogenesis of the fungus U. virens, we performed an integrated analysis of the transcriptome and metabolome of strongly (S) and weakly (W) virulent strains both before and after the infection of panicles. A total of 7932 differential expressed genes (DEGs) were identified using transcriptome analysis. Gene ontology (GO) and metabolic pathway enrichment analysis indicated that amino acid metabolism, autophagy-yeast, MAPK signaling pathway-yeast, and starch and sucrose metabolism were closely related to the pathogenicity of U. virens. Genes related to pathogenicity were significantly upregulated in the strongly virulent strain, and were ATG, MAPK, STE, TPS, and NTH genes. However, genes involved in the negative regulation of pathogenesis were significantly downregulated and contained TOR kinase, TORC1, and autophagy-related protein genes. Metabolome analysis identified 698 differentially accumulated metabolites (DAMs), including 13 categories of organic acids and derivatives, lipids and lipid-like molecules, organoheterocyclic compounds. The significantly enriched pathways of DAMs mainly included amino acids and carbohydrates, and they accumulated after infection by the S strain. To understand the relevance of DEGs and DAMs in the pathogenicity of U. virens, transcriptomic and metabolomic data were integrated and analyzed. These results further confirmed that the pathogenesis of U. virens was regulated by DEGs and DAMs related to these four pathways, involving arginine and proline metabolism, lysine biosynthesis, alanine, aspartate and glutamate metabolism, and starch and sugar metabolism. Therefore, we speculate that the pathogenicity of U. virens is closely related to the accumulation of amino acids and carbohydrates, and to the changes in the expression of related genes.
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Affiliation(s)
- Rongtao Fu
- Institute of Plant Protection, Sichuan Academy of Agricultural Science, 20# Jingjusi Road, Chengdu 610066, China
- Key Laboratory of Integrated Pest Management on Crops in Southwest, Ministry of Agriculture, Chengdu 610066, China
| | - Jian Wang
- Institute of Plant Protection, Sichuan Academy of Agricultural Science, 20# Jingjusi Road, Chengdu 610066, China
- Key Laboratory of Integrated Pest Management on Crops in Southwest, Ministry of Agriculture, Chengdu 610066, China
| | - Cheng Chen
- Institute of Plant Protection, Sichuan Academy of Agricultural Science, 20# Jingjusi Road, Chengdu 610066, China
- Key Laboratory of Integrated Pest Management on Crops in Southwest, Ministry of Agriculture, Chengdu 610066, China
| | - Yao Liu
- Environment-Friendly Crop Germplasm Innovation and Genetic Improvement Key Laboratory of Sichuan Province, Crop Research Institute, Sichuan Academy of Agricultural Science, Chengdu 610066, China
| | - Liyu Zhao
- Institute of Plant Protection, Sichuan Academy of Agricultural Science, 20# Jingjusi Road, Chengdu 610066, China
| | - Daihua Lu
- Institute of Plant Protection, Sichuan Academy of Agricultural Science, 20# Jingjusi Road, Chengdu 610066, China
- Key Laboratory of Integrated Pest Management on Crops in Southwest, Ministry of Agriculture, Chengdu 610066, China
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Abah F, Kuang Y, Biregeya J, Abubakar YS, Ye Z, Wang Z. Mitogen-Activated Protein Kinases SvPmk1 and SvMps1 Are Critical for Abiotic Stress Resistance, Development and Pathogenesis of Sclerotiophoma versabilis. J Fungi (Basel) 2023; 9:455. [PMID: 37108909 PMCID: PMC10142639 DOI: 10.3390/jof9040455] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 03/31/2023] [Accepted: 04/04/2023] [Indexed: 04/29/2023] Open
Abstract
Mitogen-activated protein kinase (MAPK) signaling pathways are evolutionarily conserved in eukaryotes and modulate responses to both internal and external stimuli. Pmk1 and Mps MAPK pathways regulate stress tolerance, vegetative growth and cell wall integrity in Saccharomyces cerevisiae and Pyricularia oryzae. Here, we deployed genetic and cell biology strategies to investigate the roles of the orthologs of Pmk1 and Mps1 in Sclerotiophoma versabilis (herein referred to as SvPmk1 and SvMps1, respectively). Our results showed that SvPmk1 and SvMps1 are involved in hyphal development, asexual reproduction and pathogenesis in S. versabilis. We found that ∆Svpmk1 and ∆Svmps1 mutants have significantly reduced vegetative growths on PDA supplemented with osmotic stress-inducing agents, compared to the wild type, with ∆Svpmps1 being hypersensitive to hydrogen peroxide. The two mutants failed to produce pycnidia and have reduced pathogenicity on Pseudostellaria heterophylla. Unlike SvPmk1, SvMps1 was found to be indispensable for the fungal cell wall integrity. Confocal microscopic analyses revealed that SvPmk1 and SvMps1 are ubiquitously expressed in the cytosol and nucleus. Taken together, we demonstrate here that SvPmk1 and SvMps1 play critical roles in the stress resistance, development and pathogenesis of S. versabilis.
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Affiliation(s)
- Felix Abah
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, College of Life Sciences & College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yunbo Kuang
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, College of Life Sciences & College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- The Engineering Technology Research Center of Characteristic Medicinal Plants of Fujian, College of Life Sciences, Ningde Normal University, Ningde 352100, China
| | - Jules Biregeya
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, College of Life Sciences & College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yakubu Saddeeq Abubakar
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, College of Life Sciences & College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zuyun Ye
- The Engineering Technology Research Center of Characteristic Medicinal Plants of Fujian, College of Life Sciences, Ningde Normal University, Ningde 352100, China
| | - Zonghua Wang
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, College of Life Sciences & College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Fujian Provincial Key Laboratory on Conservation and Sustainable Utilization of Marine Biodiversity, Fuzhou Institute of Oceanography, Minjiang University, Fuzhou 350108, China
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Appressoria-Small but Incredibly Powerful Structures in Plant-Pathogen Interactions. Int J Mol Sci 2023; 24:ijms24032141. [PMID: 36768468 PMCID: PMC9917257 DOI: 10.3390/ijms24032141] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/16/2023] [Accepted: 01/18/2023] [Indexed: 01/25/2023] Open
Abstract
Plant-pathogenic fungi are responsible for many of the most severe crop diseases in the world and remain very challenging to control. Improving current protection strategies or designating new measures based on an overall understanding of molecular host-pathogen interaction mechanisms could be helpful for disease management. The attachment and penetration of the plant surface are the most important events among diverse plant-fungi interactions. Fungi evolved as small but incredibly powerful infection structure appressoria to facilitate attachment and penetration. Appressoria are indispensable for many diseases, such as rusts, powdery mildews, and blast diseases, as well as devastating oomycete diseases. Investigation into the formation of plant-pathogen appressoria contributes to improving the understanding of the molecular mechanisms of plant-pathogen interactions. Fungal host attachment is a vital step of fungal pathogenesis. Here, we review recent advances in the molecular mechanisms regulating the formation of appressoria. Additionally, some biocontrol agents were revealed to act on appressorium. The regulation of fungal adhesion during the infective process by acting on appressoria formation is expected to prevent the occurrence of crop disease caused by some pathogenic fungi.
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Biregeya J, Anjago WM, Pan S, Zhang R, Yang Z, Chen M, Felix A, Xu H, Lin Y, Nkurikiyimfura O, Abubakar YS, Wang Z, Tang W. Type 2C Protein Phosphatases MoPtc5 and MoPtc7 Are Crucial for Multiple Stress Tolerance, Conidiogenesis and Pathogenesis of Magnaporthe oryzae. J Fungi (Basel) 2022; 9:jof9010001. [PMID: 36675822 PMCID: PMC9863299 DOI: 10.3390/jof9010001] [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: 10/31/2022] [Revised: 12/12/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
Protein kinases and phosphatases catalyze the phosphorylation and dephosphorylation of their protein substrates, respectively, and these are important mechanisms in cellular signal transduction. The rice blast fungus Magnaporthe oryzae possesses 6 protein phosphatases of type 2C class, including MoPtc1, 2, 5, 6, 7 and 8. However, only very little is known about the roles of these phosphatases in filamentous fungi. Here in, we deployed genetics and molecular biology techniques to identify, characterize and establish the roles of MoPtc5 and MoPtc7 in M. oryzae development and pathogenicity. We found that during pathogen-host interaction, MoPTC7 is differentially expressed. Double deletion of MoPTC7 and MoPTC5 suppressed the fungal vegetative growth, altered its cell wall integrity and reduced its virulence. The two genes were found indispensable for stress tolerance in the phytopathogen. We also demonstrated that disruption of any of the two genes highly affected appressorium turgor generation and Mps1 and Osm1 phosphorylation levels. Lastly, we demonstrated that both MoPtc5 and MoPtc7 are localized to mitochondria of different cellular compartments in the blast fungus. Taken together, our study revealed synergistic coordination of M. oryzae development and pathogenesis by the type 2C protein phosphatases.
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Affiliation(s)
- Jules Biregeya
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Fujian Universities Key Laboratory for Plant-Microbe Interaction, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Wilfred M. Anjago
- Fujian Universities Key Laboratory for Plant-Microbe Interaction, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shu Pan
- Fujian Universities Key Laboratory for Plant-Microbe Interaction, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Ruina Zhang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zifeng Yang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Meilian Chen
- Fuzhou Institute of Oceanography, Minjiang University, Fuzhou 350108, China
| | - Abah Felix
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Huxiao Xu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yaqi Lin
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Oswald Nkurikiyimfura
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yakubu Saddeeq Abubakar
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Fujian Universities Key Laboratory for Plant-Microbe Interaction, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Department of Biochemistry, Ahmadu Bello University, Zaria 810103, Nigeria
| | - Zonghua Wang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Fujian Universities Key Laboratory for Plant-Microbe Interaction, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Fuzhou Institute of Oceanography, Minjiang University, Fuzhou 350108, China
- Correspondence: (Z.W.); (W.T.)
| | - Wei Tang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Fujian Universities Key Laboratory for Plant-Microbe Interaction, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Correspondence: (Z.W.); (W.T.)
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Glutamine Synthetase Contributes to the Regulation of Growth, Conidiation, Sclerotia Development, and Resistance to Oxidative Stress in the Fungus Aspergillus flavus. Toxins (Basel) 2022; 14:toxins14120822. [PMID: 36548719 PMCID: PMC9785230 DOI: 10.3390/toxins14120822] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/12/2022] [Accepted: 11/21/2022] [Indexed: 11/27/2022] Open
Abstract
The basic biological function of glutamine synthetase (Gs) is to catalyze the conversion of ammonium and glutamate to glutamine. This synthetase also performs other biological functions. However, the roles of Gs in fungi, especially in filamentous fungi, are not fully understood. Here, we found that conditional disruption of glutamine synthetase (AflGsA) gene expression in Aspergillus flavus by using a xylose promoter leads to a complete glutamine deficiency. Supplementation of glutamine could restore the nutritional deficiency caused by AflGsA expression deficiency. Additionally, by using the xylose promoter for the downregulation of AflgsA expression, we found that AflGsA regulates spore and sclerotic development by regulating the transcriptional levels of sporulation genes abaA and brlA and the sclerotic generation genes nsdC and nsdD, respectively. In addition, AflGsA was found to maintain the balance of reactive oxygen species (ROS) and to aid in resisting oxidative stress. AflGsA is also involved in the regulation of light signals through the production of glutamine. The results also showed that the recombinant AflGsA had glutamine synthetase activity in vitro and required the assistance of metal ions. The inhibitor molecule L-α-aminoadipic acid suppressed the activity of rAflGsA in vitro and disrupted the morphogenesis of spores, sclerotia, and colonies in A. flavus. These results provide a mechanistic link between nutrition metabolism and glutamine synthetase in A. flavus and suggest a strategy for the prevention of fungal infection.
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Co CM, Mulgaonkar A, Zhou N, Harris S, Öz OK, Tang L, Sun X. PET Imaging of Active Invasive Fungal Infections with d-[5- 11C]-Glutamine. ACS Infect Dis 2022; 8:1663-1673. [PMID: 35869564 DOI: 10.1021/acsinfecdis.2c00249] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The increasing prevalence and severity of invasive fungal infections (IFIs), especially in immunocompromised populations, has amplified the need for rapid diagnosis of fungal pathogens. Radiotracers derived from d-amino acids (DAAs) show promise as bacterial-specific positron emission tomography (PET) imaging agents due to their preferential consumption by bacteria and largely nonutilization by hosts. Unlike mammals, fungi can utilize external DAAs including d-glutamine for their growth by rapidly upregulating DAA oxidases. Additionally, glutamine is essential for fungal nitrogen assimilation, survival, and virulence. We previously validated d-[5-11C]-glutamine (d-[5-11C]-Gln) as an efficient radiotracer targeting live bacterial soft-tissue infections. Here, we further expanded this investigation to evaluate its translational potential for PET imaging of IFIs in immunocompetent mouse models subcutaneously (SubQ) and intramuscularly (IM) infected with Candida albicans (C. albicans), using its l-isomer counterpart (l-[5-11C]-Gln) as a control. Comparative studies between pathogens showed significantly (p < 0.05) higher uptake in fungi (C. albicans and C. tropicalis) versus tested bacterial species for d-[5-11C]-Gln, suggesting that it could potentially serve as a more sensitive radiotracer for detection of fungal infections. Additionally, comparative PET imaging studies in immunocompetent infected mice demonstrated significantly higher infection-to-background ratios for d- versus l-[5-11C]-Gln in both SubQ (ratio = 1.97, p = 0.043) and IM (ratio = 1.97, p = 0.028) infections. Fungal infection imaging specificity was confirmed with no significant difference observed between localized inflammation sites versus untreated muscle background (heat-killed injection site/untreated muscle: ∼1.1). Taken together, this work demonstrates the translational potential of d-[5-11C]-Gln for noninvasive PET imaging of IFIs.
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Affiliation(s)
- Cynthia M Co
- Department of Bioengineering, University of Texas at Arlington, Arlington, Texas 76019, United States
| | - Aditi Mulgaonkar
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Ning Zhou
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Shelby Harris
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Orhan K Öz
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Liping Tang
- Department of Bioengineering, University of Texas at Arlington, Arlington, Texas 76019, United States
| | - Xiankai Sun
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
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Batool W, Liu C, Fan X, Zhang P, Hu Y, Wei Y, Zhang SH. AGC/AKT Protein Kinase SCH9 Is Critical to Pathogenic Development and Overwintering Survival in Magnaporthe oryzae. J Fungi (Basel) 2022; 8:jof8080810. [PMID: 36012798 PMCID: PMC9410157 DOI: 10.3390/jof8080810] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 07/25/2022] [Accepted: 07/27/2022] [Indexed: 02/06/2023] Open
Abstract
Primary inoculum that survives overwintering is one of the key factors that determine the outbreak of plant disease. Pathogenic resting structures, such as chlamydospores, are an ideal inoculum for plant disease. Puzzlingly, Magnaporthe oryzae, a devastating fungal pathogen responsible for blast disease in rice, hardly form any morphologically changed resting structures, and we hypothesize that M. oryzae mainly relies on its physiological alteration to survive overwintering or other harsh environments. However, little progress on research into regulatory genes that facilitate the overwintering of rice blast pathogens has been made so far. Serine threonine protein kinase AGC/AKT, MoSch9, plays an important role in the spore-mediated pathogenesis of M. oryzae. Building on this finding, we discovered that in genetic and biological terms, MoSch9 plays a critical role in conidiophore stalk formation, hyphal-mediated pathogenesis, cold stress tolerance, and overwintering survival of M. oryzae. We discovered that the formation of conidiophore stalks and disease propagation using spores was severely compromised in the mutant strains, whereas hyphal-mediated pathogenesis and the root infection capability of M. oryzae were completely eradicated due to MoSch9 deleted mutants’ inability to form an appressorium-like structure. Most importantly, the functional and transcriptomic study of wild-type and MoSch9 mutant strains showed that MoSch9 plays a regulatory role in cold stress tolerance of M. oryzae through the transcription regulation of secondary metabolite synthesis, ATP hydrolyzing, and cell wall integrity proteins during osmotic stress and cold temperatures. From these results, we conclude that MoSch9 is essential for fungal infection-related morphogenesis and overwintering of M. oryzae.
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Zhang P, Fang Z, Song Y, Wang S, Bao L, Liu M, Dang Y, Wei Y, Zhang SH. Aspartate Transaminase AST2 Involved in Sporulation and Necrotrophic Pathogenesis in the Hemibiotrophs Magnaporthe oryzae and Colletotrichum graminicola. Front Microbiol 2022; 13:864866. [PMID: 35479642 PMCID: PMC9037547 DOI: 10.3389/fmicb.2022.864866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 02/10/2022] [Indexed: 11/23/2022] Open
Abstract
Aspartate family includes five additional amino acids other than aspartate, among which most except aspartate have been reported for their action in pathogenesis by amino acid biosynthesis. However, how aspartate, the initial substrate of this family metabolic pathway, is involved in pathogenesis remains unknown. Here, we focused on aspartate transaminase (AST) that catalyzes transamination reaction between glutamate-aspartate in Magnaporthe oryzae. Three MoAST genes were bioinformatically analyzed, of which MoAST2 was uniquely upregulated when invasive hyphae switched to necrotrophic pathogenesis. MoAST2 deletion (ΔMoast2) caused a drastic reduction in conidiogenesis and appressorium formation. Particularly, ΔMoast2 was observed to be proliferated at the biotrophic phase but inhibited at the necrotrophic stage, and with invisible symptoms detected, suggesting a critical role in necrotrophic phase. Glutamate family restored the ΔMoast2 defects but aspartate family did not, inferring that transamination occurs from aspartate to glutamine. MoAST2 is cytosolic and possessed H2O2 stress tolerance. In parallel, Colletotrichum graminicola AST2, CgAST2 was proven to be a player in necrotrophic anthracnose development. Therefore, conserved AST2 is qualified to be a drug target for disease control.
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Affiliation(s)
- Penghui Zhang
- College of Plant Sciences, Jilin University, Changchun, China
| | - Zhenyu Fang
- College of Plant Sciences, Jilin University, Changchun, China
| | - Yanyue Song
- College of Plant Sciences, Jilin University, Changchun, China
| | - Shaowei Wang
- College of Plant Sciences, Jilin University, Changchun, China
| | - Lina Bao
- College of Plant Sciences, Jilin University, Changchun, China
| | - Mingyu Liu
- College of Plant Sciences, Jilin University, Changchun, China
| | - Yuejia Dang
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Yi Wei
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Shi-Hong Zhang
- College of Plant Sciences, Jilin University, Changchun, China.,College of Plant Protection, Shenyang Agricultural University, Shenyang, China
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