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Lu Z, Zhu Q, Bai Y, Zhao X, Wang H, Peng X, Luo Z, Zhang Y. A fungal pathogen secretes a cell wall-associated β-N-acetylhexosaminidase that is co-expressed with chitinases to contribute to infection of insects. PEST MANAGEMENT SCIENCE 2024; 80:4699-4713. [PMID: 38771009 DOI: 10.1002/ps.8185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 04/23/2024] [Accepted: 05/07/2024] [Indexed: 05/22/2024]
Abstract
BACKGROUND β-N-acetylhexosaminidases (HEXs) are widely distributed in fungi and involved in cell wall chitin metabolism and utilization of chitin-containing substrates. However, details of the fungal pathogens-derived HEXs in the interaction with their hosts remain limited. RESULTS An insect nutrients-induced β-N-acetylhexosaminidase, BbHex1, was identified from the entomopathogenic fungus Beauveria bassiana, which was involved in cell wall modification and degradation of insect cuticle. BbHex1 was localized to cell wall and secreted, and displayed enzyme activity to degrade the chitinase-hydrolyzed product (GlcNAc)2. Disruption of BbHex1 resulted in a significant decrease in the level of cell wall chitin in the presence of insect nutrients and during infection of insects, with impaired ability to penetrate insect cuticle, accompanying downregulated cell wall metabolism-involved and cuticle-degrading chitinase genes. However, the opposite phenotypes were examined in the gene overexpression strain. Distinctly altered cell wall structures caused by BbHex1 mutation and overexpression led to the easy activation and evasion (respectively) of insect immune response during fungal infection. As a result, BbHex1 contributed to fungal virulence. Bioinformatics analysis revealed that promoters of some co-expressed chitinase genes with the BbHex1 promoter shared conserved transcription factors Skn7, Msn2 and Ste12, and CreA-binding motifs, implying co-regulation of those genes with BbHex1. CONCLUSION These data support a mechanism that the fungal pathogen specifically expresses BbHex1, which is co-expressed with chitinases to modify cell wall for evasion of insect immune recognition and to degrade insect cuticle, and contributes to the fungal virulence against insects. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Zhuoyue Lu
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People's Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Beibei Culture Collection of Chongqing Agricultural Microbiology, Chongqing, People's Republic of China
| | - Qiankuan Zhu
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People's Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Beibei Culture Collection of Chongqing Agricultural Microbiology, Chongqing, People's Republic of China
| | - Yuting Bai
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People's Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Beibei Culture Collection of Chongqing Agricultural Microbiology, Chongqing, People's Republic of China
| | - Xin Zhao
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People's Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Beibei Culture Collection of Chongqing Agricultural Microbiology, Chongqing, People's Republic of China
| | - Huifang Wang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People's Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Beibei Culture Collection of Chongqing Agricultural Microbiology, Chongqing, People's Republic of China
| | - Xinxin Peng
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People's Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Beibei Culture Collection of Chongqing Agricultural Microbiology, Chongqing, People's Republic of China
| | - Zhibing Luo
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People's Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Beibei Culture Collection of Chongqing Agricultural Microbiology, Chongqing, People's Republic of China
| | - Yongjun Zhang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People's Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Beibei Culture Collection of Chongqing Agricultural Microbiology, Chongqing, People's Republic of China
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Deng J, Huang S, Kan Y, Song Y, Zhao X, Li N, Yao X, Luo Z, Zhang Y. A transcription factor-mediated regulatory network controls fungal pathogen colonization of insect body cavities. mBio 2024; 15:e0350423. [PMID: 38747587 PMCID: PMC11237471 DOI: 10.1128/mbio.03504-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 04/15/2024] [Indexed: 06/04/2024] Open
Abstract
Successful host tissue colonization is crucial for fungal pathogens to cause mycosis and complete the infection cycle, in which fungal cells undergo a series of morphological transition-included cellular events to combat with hosts. However, many transcription factors (TFs) and their mediated networks regulating fungal pathogen colonization of host tissue are not well characterized. Here, a TF (BbHCR1)-mediated regulatory network was identified in an insect pathogenic fungus, Beauveria bassiana, that controlled insect hemocoel colonization. BbHCR1 was highly expressed in fungal cells after reaching insect hemocoel and controlled the yeast (in vivo blastospores)-to-hyphal morphological switch, evasion of immune defense response, and fungal virulence. Comparative analysis of RNA sequencing and chromatin immunoprecipitation sequencing identified a core set of BbHCR1 target genes during hemocoel colonization, in which abaA and brlA were targeted to limit the rapid switch from blastospores to hyphae and fungal virulence. Two targets encoding hypothetical proteins, HP1 and HP2, were activated and repressed by BbHCR1, respectively, which acted as a virulence factor and repressor, respectively, suggesting that BbHCR1 activated virulence factors but repressed virulence repressors during the colonization of insect hemocoel. BbHCR1 tuned the expression of two dominant hemocoel colonization-involved metabolite biosynthetic gene clusters, which linked its regulatory role in evasion of immune response. Those functions of BbHCR1 were found to be collaboratively regulated by Fus3- and Hog1-MAP kinases via phosphorylation. These findings have drawn a regulatory network in which Fus3- and Hog1-MAP kinases phosphorylate BbHCR1, which in turn controls the colonization of insect body cavities by regulating fungal morphological transition and virulence-implicated genes.IMPORTANCEFungal pathogens adopt a series of tactics for successful colonization in host tissues, which include morphological transition and the generation of toxic and immunosuppressive molecules. However, many transcription factors (TFs) and their linked pathways that regulate tissue colonization are not well characterized. Here, we identified a TF (BbHCR1)-mediated regulatory network that controls the insect fungal pathogen, Beauveria bassiana, colonization of insect hemocoel. During these processes, BbHCR1 targeted the fungal central development pathway for the control of yeast (blastospores)-to-hyphae morphological transition, activated virulence factors, repressed virulence repressors, and tuned the expression of two dominant hemocoel colonization-involved immunosuppressive and immunostimulatory metabolite biosynthetic gene clusters. The BbHCR1 regulatory function was governed by Fus3- and Hog1-MAP kinases. These findings led to a new regulatory network composed of Fus3- and Hog1-MAP kinases and BbHCR1 that control insect body cavity colonization by regulating fungal morphological transition and virulence-implicated genes.
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Affiliation(s)
- Juan Deng
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- Beibei Culture Collection of Chongqing Agricultural Microbiology, Southwest University, Chongqing, China
| | - Shuaishuai Huang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- Beibei Culture Collection of Chongqing Agricultural Microbiology, Southwest University, Chongqing, China
- Ministry of Education Key Laboratory of Biodiversity and Eco-Environmental Protection of the Qinghai-Tibetan Plateau, School of Ecology and Environment, Tibet University, Tibet, China
| | - Yanze Kan
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- Beibei Culture Collection of Chongqing Agricultural Microbiology, Southwest University, Chongqing, China
| | - Yue Song
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- Beibei Culture Collection of Chongqing Agricultural Microbiology, Southwest University, Chongqing, China
| | - Xin Zhao
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- Beibei Culture Collection of Chongqing Agricultural Microbiology, Southwest University, Chongqing, China
| | - Ning Li
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- Beibei Culture Collection of Chongqing Agricultural Microbiology, Southwest University, Chongqing, China
| | - Xuewen Yao
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- Beibei Culture Collection of Chongqing Agricultural Microbiology, Southwest University, Chongqing, China
| | - Zhibing Luo
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- Beibei Culture Collection of Chongqing Agricultural Microbiology, Southwest University, Chongqing, China
| | - Yongjun Zhang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- Beibei Culture Collection of Chongqing Agricultural Microbiology, Southwest University, Chongqing, China
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Li F, Zhang J, Zhong H, Yu K, Chen J. Comprehensive Insights into the Remarkable Function and Regulatory Mechanism of FluG during Asexual Development in Beauveria bassiana. Int J Mol Sci 2024; 25:6261. [PMID: 38892450 PMCID: PMC11173134 DOI: 10.3390/ijms25116261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 05/24/2024] [Accepted: 05/31/2024] [Indexed: 06/21/2024] Open
Abstract
Asexual development is the main propagation and transmission mode of Beauveria bassiana and the basis of its pathogenicity. The regulation mechanism of conidiation and the key gene resources for utilization are key links to improving the conidia yield and quality of Beauveria bassiana. Their clarification may promote the industrialization of fungal pesticides. Here, we compared the regulation of morphology, resistance to external stress, virulence, and nutrient utilization capacity between the upstream developmental regulatory gene fluG and the key genes brlA, abaA, and wetA in the central growth and development pathway. The results showed that the ΔbrlA and ΔabaA mutants completely lost the capacity to conidiate and that the ΔwetA mutant had seriously reduced conidiation capacity. Although the deletion of fluG did not reduce the conidiation ability as much as deletions of brlA, abaA, and wetA, it significantly reduced the fungal response to external stress, virulence, and nutrient utilization, while the deletion of the three other genes had little effect. Via transcriptome analysis and screening the yeast nuclear system library, we found that the differentially expressed genes in the ΔfluG mutants were concentrated in the signaling pathways of ABC transporters, propionate metabolism, tryptophan metabolism, DNA replication, mismatch repair, and fatty acid metabolism. FluG directly acted on 40 proteins that were involved in various signaling pathways such as metabolism, oxidative stress, and cell homeostasis. The analysis indicated that the regulatory function of fluG was mainly involved in DNA replication, cell homeostasis, fungal growth and metabolism, and the response to external stress. Our results revealed the biological function of fluG in asexual development and the responses to several environmental stresses as well as its influence on the asexual development regulatory network in B. bassiana.
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Affiliation(s)
| | - Juefeng Zhang
- Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (F.L.); (H.Z.); (K.Y.)
| | | | | | - Jianming Chen
- Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (F.L.); (H.Z.); (K.Y.)
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Peng YJ, Zhang H, Wang G, Feng MG, Ying SH. MARVEL family proteins contribute to vegetative growth, development, and virulence of the insect fungal pathogen Beauveria bassiana. J Invertebr Pathol 2024; 203:108076. [PMID: 38382734 DOI: 10.1016/j.jip.2024.108076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 02/07/2024] [Accepted: 02/18/2024] [Indexed: 02/23/2024]
Abstract
Beauveria bassiana is one of the most extensively studied entomopathogenic fungi (EPF) and is widely used as a biocontrol agent against various insect pests. Proteins containing the MARVEL domain are conserved in eukaryotes, typically with four transmembrane structures. In this study, we identified the five MARVEL domain proteins in B. bassiana. Five MARVEL domain proteins were localized to cytomembrane and vacuoles in B. bassiana, but had different roles in maintaining the lipid-droplet homeostasis. These proteins were required for fungal virulence, but differentially contributed to fungal utilization of nutrients, stress tolerance, and development under aerial and submerged conditions. Notably, BbMARVEL2 was essential for conidial surface morphology. Additionally, these five MARVEL domain proteins contributed to fungal interaction with the host immune defense. This study provides new mechanistic insights into the life cycle of B. bassiana as a biocontrol agent.
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Affiliation(s)
- Yue-Jin Peng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China; College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
| | - Hao Zhang
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Guang Wang
- College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
| | - Ming-Guang Feng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Sheng-Hua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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5
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Cai Q, Tian L, Xie JT, Jiang DH. Two sirtuin proteins, Hst3 and Hst4, modulate asexual development, stress tolerance, and virulence by affecting global gene expression in Beauveria bassiana. Microbiol Spectr 2024; 12:e0313723. [PMID: 38193686 PMCID: PMC10846017 DOI: 10.1128/spectrum.03137-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 12/01/2023] [Indexed: 01/10/2024] Open
Abstract
Beauveria bassiana is a widely used entomopathogenic fungus in insect biological control applications. In this study, we investigated the role of two sirtuin homologs, BbHst3 and BbHst4, in the biological activities and pathogenicity of B. bassiana. Our results showed that deletion of BbHst3 and/or BbHst4 led to impaired sporulation, reduced (~50%) conidial production, and decreased tolerance to various stresses, including osmotic, oxidative, and cell wall-disturbing agents. Moreover, BbHst4 plays dominant roles in histone H3-K56 acetylation and DNA damage response, while BbHst3 is more responsible for maintaining cell wall integrity. Transcriptomic analyses revealed significant changes (>1,500 differentially expressed genes) in gene expression patterns in the mutant strains, particularly in genes related to secondary metabolism, detoxification, and transporters. Furthermore, the ΔBbHst3, ΔBbHst4, and ΔBbHst3ΔBbHst4 strains exhibited reduced virulence in insect bioassays, with decreased (~20%) abilities to kill insect hosts through topical application and intra-hemocoel injection. These findings highlight the crucial role of BbHst3 and BbHst4 in sporulation, DNA damage repair, cell wall integrity, and fungal infection in B. bassiana. Our study provides new insights into the regulatory mechanisms underlying the biological activities and pathogenicity of B. bassiana and emphasizes the potential of targeting sirtuins for improving the efficacy of fungal biocontrol agents.IMPORTANCESirtuins, as a class of histone deacetylases, have been shown to play important roles in various cellular processes in fungi, including asexual development, stress response, and pathogenicity. By investigating the functions of BbHst3 and BbHst4, we have uncovered their critical contributions to important phenotypes in Beauveria bassiana. Deletion of these sirtuin homologs led to reduced conidial yield, increased sensitivity to osmotic and oxidative stresses, impaired DNA damage repair processes, and decreased fungal virulence. Transcriptomic analyses showed differential expression of numerous genes involved in secondary metabolism, detoxification, transporters, and virulence-related factors, potentially uncovering new targets for manipulation and optimization of fungal biocontrol agents. Our study also emphasizes the significance of sirtuins as key regulators in fungal biology and highlights their potential as promising targets for the development of novel antifungal strategies.
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Affiliation(s)
- Qing Cai
- College of Plant Science and Technology, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Li Tian
- Department of Bioengineering, Shandong Provincial Key Laboratory of Microbial Engineering, Qilu University of Technology, Jinan, Shandong, China
| | - Jia-Tao Xie
- College of Plant Science and Technology, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Dao-Hong Jiang
- College of Plant Science and Technology, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, China
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Du Y, Li J, Chen S, Xia Y, Jin K. Pathogenicity analysis and comparative genomics reveal the different infection strategies between the generalist Metarhizium anisopliae and the specialist Metarhizium acridum. PEST MANAGEMENT SCIENCE 2024; 80:820-836. [PMID: 37794279 DOI: 10.1002/ps.7812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 08/28/2023] [Accepted: 09/30/2023] [Indexed: 10/06/2023]
Abstract
BACKGROUND The fungal genera Metarhizium contain many important multiple species that are used as biocontrol agents and as model organisms for exploring insect-fungal interactions. Metarhizium spp. exhibit different traits of pathogenicity, suggesting that the pathogenesis can be quite distinctive. However, the underlying differences in their pathogenesis remain poorly understood. RESULTS Pathogenicity analysis showed that Metarhizium anisopliae (strain CQMa421) displayed higher virulence against oriental migratory locusts, Locusta migratoria manilensis (Meyen), than the acridid-specific specie Metarhizium acridum (strain CQMa102). Relative to M. acridum, M. anisopliae possessed a higher conidial hydrophobicity, increased ability to penetrate the host, accelerated growth under hypoxia and enhanced ability for the utilization of different carbon sources. Different distributions of carbohydrate epitopes at cell wall surface of M. anisopliae might also contribute to successful evasion of host immune defenses. Comparative genomics showed that M. anisopliae has 98 more virulence-related secreted proteins (133) than M. acridum (35), which can be functionally classified as hydrolases, virulence effectors, cell wall degradation and stress tolerance-related proteins, and helpful to the cuticle penetration and host internal environment adaption. In addition, differences in genomic clusters specifically related to secondary metabolites, including the clusters of Indole-NRPS hybrid, T1PKS-NRPS like hybrid, Betalactone, Fungal-Ripp and NRPS-Terpene hybrid, may lead to differences in core virulence-related secondary metabolite genes in M. acridum (18) and M. anisopliae (36). CONCLUSION The comparative study provided new insights into the different infection strategies between M. anisopliae and M. acridum, and further facilitate the identification of virulence-related genes for the improvement of mycoinsecticides. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Yanru Du
- School of Life Sciences, Chongqing University, Chongqing, P. R. China
- Chongqing Engineering Research Center for Fungal Insecticide, Chongqing, P. R. China
- Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing, P. R. China
| | - Jun Li
- School of Life Sciences, Chongqing University, Chongqing, P. R. China
- Chongqing Engineering Research Center for Fungal Insecticide, Chongqing, P. R. China
- Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing, P. R. China
| | - Shaopeng Chen
- Tobacco Leaf Branch of Chongqing Tobacco Company of China Tobacco Corporation, Chongqing, P. R. China
| | - Yuxian Xia
- School of Life Sciences, Chongqing University, Chongqing, P. R. China
- Chongqing Engineering Research Center for Fungal Insecticide, Chongqing, P. R. China
- Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing, P. R. China
| | - Kai Jin
- School of Life Sciences, Chongqing University, Chongqing, P. R. China
- Chongqing Engineering Research Center for Fungal Insecticide, Chongqing, P. R. China
- Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing, P. R. China
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Ma M, Luo J, Li C, Eleftherianos I, Zhang W, Xu L. A life-and-death struggle: interaction of insects with entomopathogenic fungi across various infection stages. Front Immunol 2024; 14:1329843. [PMID: 38259477 PMCID: PMC10800808 DOI: 10.3389/fimmu.2023.1329843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 12/15/2023] [Indexed: 01/24/2024] Open
Abstract
Insects constitute approximately 75% of the world's recognized fauna, with the majority of species considered as pests. Entomopathogenic fungi (EPF) are parasitic microorganisms capable of efficiently infecting insects, rendering them potent biopesticides. In response to infections, insects have evolved diverse defense mechanisms, prompting EPF to develop a variety of strategies to overcome or circumvent host defenses. While the interaction mechanisms between EPF and insects is well established, recent findings underscore that their interplay is more intricate than previously thought, especially evident across different stages of EPF infection. This review primarily focuses on the interplay between EPF and the insect defense strategies, centered around three infection stages: (1) Early infection stage: involving the pre-contact detection and avoidance behavior of EPF in insects, along with the induction of behavioral responses upon contact with the host cuticle; (2) Penetration and intra-hemolymph growth stage: involving the initiation of intricate cellular and humoral immune functions in insects, while symbiotic microbes can further contribute to host resistance; (3) Host insect's death stage: involving the ultimate confrontation between pathogens and insects. Infected insects strive to separate themselves from the healthy population, while pathogens rely on the infected insects to spread to new hosts. Also, we discuss a novel pest management strategy underlying the cooperation between EPF infection and disturbing the insect immune system. By enhancing our understanding of the intricate interplay between EPF and the insect, this review provides novel perspectives for EPF-mediated pest management and developing effective fungal insecticides.
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Affiliation(s)
- Meiqi Ma
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Jing Luo
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Chong Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Ioannis Eleftherianos
- Infection and Innate Immunity Laboratory, Department of Biological Sciences, Institute for Biomedical Sciences, The George Washington University, Washington, DC, United States
| | - Wei Zhang
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering (Ministry of Education), Guizhou University, Guiyang, China
| | - Letian Xu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
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Lei JH, Sun TF, Feng MG, Ying SH. Functional insights of three RING-finger peroxins in the life cycle of the insect pathogenic fungus Beauveria bassiana. Curr Genet 2023; 69:267-276. [PMID: 37910177 DOI: 10.1007/s00294-023-01275-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 10/22/2023] [Accepted: 10/24/2023] [Indexed: 11/03/2023]
Abstract
Peroxisomes play important roles in fungal physiological processes. The RING-finger complex consists of peroxins Pex2, Pex10, and Pex12 and is essential for recycling of receptors responsible for peroxisomal targeting of matrix proteins. In this study, these three peroxins were functionally characterized in the entomopathogenic fungus Beauveria bassiana (Bb). These three peroxins are associated with peroxisomes, in which BbPex2 interacted with BbPex10 and BbPex12. Ablation of these peroxins did not completely block the peroxisome biogenesis, but abolish peroxisomal targeting of matrix proteins via both PTS1 and PTS2 pathways. Three disruptants displayed different phenotypic defects in growth on nutrients and under stress conditions, but have similar defects in acetyl-CoA biosynthesis, development, and virulence. Strikingly, BbPex10 played a less important role in fungal growth on tested nutrients than other two peroxins; whereas, BbPex2 performed a less important contribution to fungal growth under stresses. This investigation reinforces the peroxisomal roles in the lifecycle of entomopathogenic fungi and highlights the unequal functions of different peroxins in peroxisomal biology.
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Affiliation(s)
- Jia-Hui Lei
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Ting-Fei Sun
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Ming-Guang Feng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Sheng-Hua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
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9
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Ding JL, Wei K, Feng MG, Ying SH. Homologs of bacterial heat-labile enterotoxin subunit A contribute to development, stress response, and virulence in filamentous entomopathogenic fungus Beauveria bassiana. Front Immunol 2023; 14:1264560. [PMID: 37809075 PMCID: PMC10556748 DOI: 10.3389/fimmu.2023.1264560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 09/04/2023] [Indexed: 10/10/2023] Open
Abstract
Introduction Enterotoxigenic bacteria commonly excrete heat-labile enterotoxins (LT) as virulence factors that consist of one subunit A (LTA) and five B subunits (LTB). In fungi, there are a large number of genes encoding the homologs of LTA, but their biological roles remain largely unknown. Methods In this study, we identified 14 enterotoxin_A domain proteins in filamentous fungus B. bassiana in which five proteins were functionally characterized. Results Five proteins displayed diverse sub-cellular localizations but perform convergent functions in stress response, development, and virulence. The loss of five LTA genes resulted in significant reduction in conidial production, blastospore formation, and the increased sensitivity to oxidative and cell wall -perturbing stresses. The virulence of five disruptants was notably weakened as indicated by topical and intrahemocoel injection assays. Notably, the loss of these five proteins led to the significant changes in the carbohydrate profiles of cellular surface, which induced the enhanced host immune reactions of encapsulation and melanization. Discussion Thus, LTA proteins contribute to the fungus-host interaction via maintaining the carbohydrate profiles of cellular surface. This study expands our understanding of the enterotoxin_A domain proteins in fungal physiology and deepens mechanisms involved in the lifestyle of fungal insect pathogens.
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Affiliation(s)
| | | | | | - Sheng-Hua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
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10
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Peng Y, Wen S, Wang G, Zhang X, Di T, Du G, Chen B, Zhang L. Reconstruction of Gut Bacteria in Spodoptera frugiperda Infected by Beauveria bassiana Affects the Survival of Host Pest. J Fungi (Basel) 2023; 9:906. [PMID: 37755014 PMCID: PMC10532432 DOI: 10.3390/jof9090906] [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: 07/23/2023] [Revised: 08/31/2023] [Accepted: 09/04/2023] [Indexed: 09/28/2023] Open
Abstract
Spodoptera frugiperda (Lepidoptera: Noctuidae) is a migratory agricultural pest that is devastating on a global scale. Beauveria bassiana is a filamentous entomopathogenic fungus that has a strong pathogenic effect on Lepidoptera pests but little is known about the microbial community in the host gut and the dominant populations in fungus-infected insects. B. bassiana AJS91881 was isolated and identified from the infected larvae of Spodoptera litura. The virulence of AJS91881 to the eggs, larvae, pupae and adults of S. frugiperda was measured. Moreover, the gut microbial community diversity of healthy and fungus-infected insects was analyzed. Our results showed that after treatment with B. bassiana AJS91881, the egg hatching rate, larval survival rate and adult lifespan of the insects were significantly reduced, and the pupae rigor rate was significantly increased compared to that of the control group. Additionally, the gut microbial community was reconstructed after B. bassiana infection. At the phylum and genus level, the relative abundance of the Proteobacteria and Serratia increased significantly in the B. bassiana treatment group. The KEGG function prediction results showed that fungal infection affected insect gut metabolism, environmental information processing, genetic information processing, organism systems and cellular processes. Fungal infection was closely related to the metabolism of various substances in the insect gut. Serratia marcescens was the bacterium with the highest relative abundance after infection by B. bassiana; intestinal bacteria S. marcescens inhibited the infection of insect fungi B. bassiana against the S. frugiperda. The presence of gut bacteria also significantly reduced the virulence of the fungi against the insects when compared to the group with the larvae fed antibiotics that were infected with fungal suspension (Germfree, GF) and healthy larvae that were infected with fungal suspension prepared with an antibiotic solution (+antibiotic). In conclusion, the reconstruction of the insect intestinal bacterial community is an indispensable link for understanding the pathogenicity of B. bassiana against S. frugiperda. Most importantly, in the later stage of fungal infection, the increased abundance of S. marcescens in the insect intestine inhibited the virulence of B. bassiana to some extent. The findings aid in understanding changes in the gut microbiota during the early stages of entomopathogenic fungal infection of insects and the involvement of insect gut microbes in host defense mediated by pathogenic fungal infection. This study is also conducive to understanding the interaction between entomopathogenic fungi, hosts and gut microbes, and provides a new idea for the joint use of entomopathogenic fungi and gut bacteria to control pests.
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Affiliation(s)
| | | | | | | | | | | | - Bin Chen
- Yunnan State Key Laboratory of Conservation and Utilization of Biological Resources, College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China; (Y.P.); (S.W.); (G.W.); (X.Z.); (T.D.); (G.D.)
| | - Limin Zhang
- Yunnan State Key Laboratory of Conservation and Utilization of Biological Resources, College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China; (Y.P.); (S.W.); (G.W.); (X.Z.); (T.D.); (G.D.)
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11
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Huang S, Zhao X, Luo Z, Tang X, Zhou Y, Keyhani N, Zhang Y. Fungal co-expression network analyses identify pathogen gene modules associated with host insect invasion. Microbiol Spectr 2023; 11:e0180923. [PMID: 37656157 PMCID: PMC10581046 DOI: 10.1128/spectrum.01809-23] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 07/06/2023] [Indexed: 09/02/2023] Open
Abstract
The broad host range fungal insect pathogen, Beauveria bassiana, has been commercialized as an alternative to chemical insecticides for pest control worldwide. B. bassiana represents a unique model system with which to examine host-pathogen interactions, and a wide range of genes and processes have been studied. However, significant aspects of virulence, particularly on the genomic scale, remain poorly studied. Here, we have combined available transcriptomes with three newly generated data sets for a combined total analysis of 76 deep-sequenced samples covering growth, development, stress responses, and infection during the life cycle of B. bassiana. Co-expression network analyses resulted in the identification of gene modules enriched during two critical stages of the infection process, namely (i) cuticle penetration and (ii) in vivo hyphal body (dimorphic transition) growth capable of avoiding innate and humoral immune defenses. These analyses identify unique signatures of metabolism, signaling, secondary metabolite production, host defense suppression, membrane reorganization, effector production, and secretion for each stage, including genetic regulators and epigenetic patterns. These data provide a comprehensive framework for understanding and probing fungal adaptations to its pathogenic life cycle and expand the candidate repertoire for continued dissection of the host-pathogen interaction. IMPORTANCE Insect fungal pathogens have evolved unique strategies for overcoming host structural and immunological defenses that span from the sclerotized cuticle to innate and humoral cellular responses. Two critical stages of the infection process involve (i) cuticle penetration and (ii) immune evasion within the insect hemocoel. A set of 76 global transcriptomic data for B. bassiana that include the cuticle penetration and hemocoel growth stages were analyzed for patterns (gene modules) of expression, yielding unique insights into these different life stages. These analyses integrate gene networks involved in fungal development, stress response and pathogenesis to further the systematic understanding of the global processes integral to the unique adaptation employed by fungal pathogens of insects.
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Affiliation(s)
- Shuaishuai Huang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
- Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau (Ministry of Education), School of Ecology and Environment, Tibet University, Tibet, China
| | - Xin Zhao
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
| | - Zhibing Luo
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
| | - Xiaohan Tang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
| | - Yonghong Zhou
- Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau (Ministry of Education), School of Ecology and Environment, Tibet University, Tibet, China
| | - Nemat Keyhani
- Department of Biological Sciences, University of Illinois, Chicago, Illinois, USA
| | - Yongjun Zhang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, China
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12
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Wang H, Lu Z, Keyhani NO, Deng J, Zhao X, Huang S, Luo Z, Jin K, Zhang Y. Insect fungal pathogens secrete a cell wall-associated glucanase that acts to help avoid recognition by the host immune system. PLoS Pathog 2023; 19:e1011578. [PMID: 37556475 PMCID: PMC10441804 DOI: 10.1371/journal.ppat.1011578] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 08/21/2023] [Accepted: 07/25/2023] [Indexed: 08/11/2023] Open
Abstract
Fungal insect pathogens have evolved diverse mechanisms to evade host immune recognition and defense responses. However, identification of fungal factors involved in host immune evasion during cuticular penetration and subsequent hemocoel colonization remains limited. Here, we report that the entomopathogenic fungus Beauveria bassiana expresses an endo-β-1,3-glucanase (BbEng1) that functions in helping cells evade insect immune recognition/ responses. BbEng1 was specifically expressed during infection, in response to host cuticle and hemolymph, and in the presence of osmotic or oxidative stress. BbEng1 was localized to the fungal cell surface/ cell wall, where it acts to remodel the cell wall pathogen associated molecular patterns (PAMPs) that can trigger host defenses, thus facilitating fungal cell evasion of host immune defenses. BbEng1 was secreted where it could bind to fungal cells. Cell wall β-1,3-glucan levels were unchanged in ΔBbEng1 cells derived from in vitro growth media, but was elevated in hyphal bodies, whereas glucan levels were reduced in most cell types derived from the BbEng1 overexpressing strain (BbEng1OE). The BbEng1OE strain proliferated more rapidly in the host hemocoel and displayed higher virulence as compared to the wild type parent. Overexpression of their respective Eng1 homologs or of BbEng1 in the insect fungal pathogens, Metarhizium robertsii and M. acridum also resulted in increased virulence. Our data support a mechanism by which BbEng1 helps the fungal pathogen to evade host immune surveillance by decreasing cell wall glucan PAMPs, promoting successful fungal mycosis.
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Affiliation(s)
- Huifang Wang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People’s Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, People’s Republic of China
| | - Zhuoyue Lu
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People’s Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, People’s Republic of China
| | - Nemat O. Keyhani
- Department of Biological Sciences, University of Illinois, Chicago, Illinois, United States of America
| | - Juan Deng
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People’s Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, People’s Republic of China
| | - Xin Zhao
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People’s Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, People’s Republic of China
| | - Shuaishuai Huang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People’s Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, People’s Republic of China
| | - Zhibing Luo
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People’s Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, People’s Republic of China
| | - Kai Jin
- Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing, People’s Republic of China
| | - Yongjun Zhang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing, People’s Republic of China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing, People’s Republic of China
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Zhao X, Jiang Y, Wang H, Lu Z, Huang S, Luo Z, Zhang L, Lv T, Tang X, Zhang Y. Fus3/Kss1-MAP kinase and Ste12-like control distinct biocontrol-traits besides regulation of insect cuticle penetration via phosphorylation cascade in a filamentous fungal pathogen. PEST MANAGEMENT SCIENCE 2023; 79:2611-2624. [PMID: 36890107 DOI: 10.1002/ps.7446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 12/22/2022] [Accepted: 03/08/2023] [Indexed: 06/02/2023]
Abstract
BACKGROUND Homolog of the yeast Fus3/Kss1 mitogen-activated protein kinase (MAPK) pathway and its target transcription factor, Ste12-like, are involved in penetration of host cuticle/pathogenicity in many ascomycete pathogens. However, details of their interaction during fungal infection, as well as their controlled other virulence-associated traits, are unclear. RESULTS Ste12-like (BbSte12) and Fus3/Kss1 MAPK homolog (Bbmpk1) interacted in nucleus, and phosphorylation of BbSte12 by Bbmpk1 was essential for penetration of insect cuticle in an insect fungal pathogen, Beauveria bassiana. However, some distinct biocontrol-traits were found to be mediated by Ste12 and Bbmpk1. In contrast to ΔBbmpk1 colony that grew more rapid than wild-type strain, inactivation of BbSte12 resulted in the opposite phenotype, which was consistent with their different proliferation rates in insect hemocoel after direct injection of conidia bypass the cuticle. Reduced conidial yield with decreased hydrophobicity was examined in both mutants, however they displayed distinct conidiogenesis, accompanying with differently altered cell cycle, distinct hyphal branching and septum formation. Moreover, ΔBbmpk1 showed increased tolerance to oxidative agent, whereas the opposite phenotype was seen for ΔBbSte12 strain. RNA sequencing analysis revealed that Bbmpk1 controlled 356 genes depending on BbSte12 during cuticle penetration, but 1077 and 584 genes were independently controlled by Bbmpk1 and BbSte12. CONCLUSION BbSte12 and Bbmpk1 separately participate in additional pathways for control of conidiation, growth and hyphal differentiation, as well as oxidative stress response besides regulating cuticle penetration via phosphorylation cascade. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Xin Zhao
- Academy of Agricultural Sciences, Biotechnology Research Center, Southwest University, Chongqing, P. R. China
| | - Yahui Jiang
- Academy of Agricultural Sciences, Biotechnology Research Center, Southwest University, Chongqing, P. R. China
| | - Huifang Wang
- Academy of Agricultural Sciences, Biotechnology Research Center, Southwest University, Chongqing, P. R. China
| | - Zhuoyue Lu
- Academy of Agricultural Sciences, Biotechnology Research Center, Southwest University, Chongqing, P. R. China
| | - Shuaishuai Huang
- Academy of Agricultural Sciences, Biotechnology Research Center, Southwest University, Chongqing, P. R. China
| | - Zhibing Luo
- Academy of Agricultural Sciences, Biotechnology Research Center, Southwest University, Chongqing, P. R. China
| | - Liuyi Zhang
- Academy of Agricultural Sciences, Biotechnology Research Center, Southwest University, Chongqing, P. R. China
| | - Ting Lv
- Academy of Agricultural Sciences, Biotechnology Research Center, Southwest University, Chongqing, P. R. China
| | - Xiaohan Tang
- Academy of Agricultural Sciences, Biotechnology Research Center, Southwest University, Chongqing, P. R. China
| | - Yongjun Zhang
- Academy of Agricultural Sciences, Biotechnology Research Center, Southwest University, Chongqing, P. R. China
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14
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Wang JL, Sun J, Song YJ, Zheng HH, Wang GJ, Luo WX, Li L, Liu XS. An entomopathogenic fungus exploits its host humoral antibacterial immunity to minimize bacterial competition in the hemolymph. MICROBIOME 2023; 11:116. [PMID: 37210573 DOI: 10.1186/s40168-023-01538-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 03/29/2023] [Indexed: 05/22/2023]
Abstract
BACKGROUND The insect hemolymph (blood-equivalent fluid), composed of a large number of hemocytes (blood cells) and a variety of soluble immune effectors, is hostile for pathogens including fungi. In order to survive in the insect hemocoel (body cavity), the entomopathogenic fungus (EPF) has evolved two classical coping strategies, namely evasion and suppression of the host immune reactions. However, it remains unclear whether EPF has other ways of coping with host immunity. RESULTS In this study, we demonstrated that Metarhizium rileyi (an EPF) infection by injection of blastospores into the hemocoel enhanced the plasma antibacterial activity of cotton bollworm (Helicoverpa armigera), which was partially due to the enhanced expression of antimicrobial peptides (AMPs). The early stage of M. rileyi infection induced the translocation of gut bacteria into the hemocoel, where they were subsequently cleared due to the enhanced plasma antibacterial activity. Further, we showed that the enhanced plasma antibacterial activity and AMP expression were attributable to M. rileyi but not the invasive gut bacteria (opportunistic bacteria). Elevated ecdysone (major steroid hormone in insects) levels in the hemolymph at 48 h post-M. rileyi infection might contribute to the enhanced expression of AMPs. The fungus-elicited AMPs, such as cecropin 3 or lebocin, exhibited potent inhibitory activity against the opportunistic bacteria but not against hyphal bodies. In addition, the opportunistic bacteria competed with hyphal bodies for amino acid nutrients. CONCLUSIONS M. rileyi infection induced the translocation of gut bacteria, and then the fungi activated and exploited its host humoral antibacterial immunity to eliminate opportunistic bacteria, preventing them from competing for nutrients in the hemolymph. Unlike the classical strategies, EPF utilizes to evade or suppress host immunity, our findings reveal a novel strategy of interaction between EPF and host immunity. Video Abstract.
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Affiliation(s)
- Jia-Lin Wang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Jing Sun
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Ya-Jing Song
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Huan-Huan Zheng
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Gui-Jie Wang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Wen-Xia Luo
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Li Li
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Xu-Sheng Liu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.
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15
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Ding JL, Wei K, Feng MG, Ying SH. Autophagy-Related Gene 4 Participates in the Asexual Development, Stress Response and Virulence of Filamentous Insect Pathogenic Fungus Beauveria bassiana. J Fungi (Basel) 2023; 9:jof9050543. [PMID: 37233254 DOI: 10.3390/jof9050543] [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: 04/04/2023] [Revised: 05/04/2023] [Accepted: 05/04/2023] [Indexed: 05/27/2023] Open
Abstract
Autophagy is a conserved mechanism for the turnover of intracellular components. Among the 'core' autophagy-related genes (ATGs), the cysteine protease Atg4 plays an important role in the activation of Atg8 by exposing the glycine residue at its extreme carboxyl terminus. In the insect fungal pathogen Beauveria bassiana, a yeast ortholog of Atg4 was identified and functionally analyzed. Ablation of the BbATG4 gene blocks the autophagic process during fungal growth under aerial and submerged conditions. Gene loss did not affect fungal radial growth on various nutrients, but ΔBbatg4 exhibited an impaired ability to accumulate biomass. The mutant displayed increased sensitivity to stress caused by menadione and hydrogen peroxide. ΔBbatg4 generated abnormal conidiophores with reduced production of conidia. Additionally, fungal dimorphism was significantly attenuated in gene disruption mutants. Disruption of BbATG4 resulted in significantly weakened virulence in topical and intrahemocoel injection assays. Our study indicates that BbAtg4 contributes to the lifecycle of B. bassiana via its autophagic roles.
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Affiliation(s)
- Jin-Li Ding
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Kang Wei
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Ming-Guang Feng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Sheng-Hua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
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Valieva Y, Igrunkova A, Fayzullin A, Serejnikova N, Kurkov A, Fayzullina N, Valishina D, Bakulina A, Timashev P, Shekhter A. Epimorphic Regeneration of Elastic Cartilage: Morphological Study into the Role of Cellular Senescence. BIOLOGY 2023; 12:biology12040565. [PMID: 37106768 PMCID: PMC10136161 DOI: 10.3390/biology12040565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/04/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023]
Abstract
Control over endogenous reparative mechanisms is the future of regenerative medicine. The rabbit ear defect is a rare model which allows the observation of the epimorphic regeneration of elastic cartilage. However, the mechanisms of phenotypical restoration of this highly differentiated tissue have not been studied. We modelled circular ear defects of different sizes (4, 6, and 8 mm in diameter) in 12 laboratory rabbits, and observed them during 30, 60, 90, and 120 day periods. Excised tissues were processed and analyzed by standard histological methods and special histochemical reactions for senescence associated-β-galactosidase and lectin markers. We demonstrated that larger defects caused significant elevation of senescence associated-β-galactosidase in chondrocytes. The fullness of epimorphic regeneration of elastic cartilage depended on the activation of cellular senescence and synthesis of elastic fibers. Further investigation into the role of cells with senescence-associated secretory phenotype in damaged tissues can present new targets for controlled tissue regeneration.
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Affiliation(s)
- Yana Valieva
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
| | - Aleksandra Igrunkova
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
- World-Class Research Center "Digital Biodesign and Personalized Healthcare", Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
- Department of Human Anatomy and Histology, N. V. Sklifosovsky Institute of Clinical Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
| | - Alexey Fayzullin
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
- World-Class Research Center "Digital Biodesign and Personalized Healthcare", Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
| | - Natalia Serejnikova
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
| | - Aleksandr Kurkov
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
| | - Nafisa Fayzullina
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
| | - Dina Valishina
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
| | - Alesia Bakulina
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
| | - Peter Timashev
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
- World-Class Research Center "Digital Biodesign and Personalized Healthcare", Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
| | - Anatoly Shekhter
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 8-2 Trubetskaya St., 119991 Moscow, Russia
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Hou J, Ding JL, Peng YJ, Feng MG, Ying SH. Genome-wide identification of BCS1 domain-containing proteins reveals the mitochondrial bcs1 essential for growth, stress response, and virulence of the filamentous entomopathogenic fungus Beauveria bassiana. Microbiol Res 2023; 267:127262. [PMID: 36450212 DOI: 10.1016/j.micres.2022.127262] [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: 08/13/2022] [Revised: 11/21/2022] [Accepted: 11/21/2022] [Indexed: 11/27/2022]
Abstract
In yeasts, bcs1 is a mitochondrial AAA protein (ATPase associated with diverse cellular activities) and required for biogenesis of the complex III in mitochondrial electron transfer chain. However, the presence and biological roles of bcs1 remain largely unknown in the filamentous fungi. In present study, genome-wide identification revealed that there were six BCS1-domain containing proteins (Bbbcs1a through f) in the filamentous insect pathogenic fungus Beauveria bassiana, five of which (except for Bbbcs1f) were functionally analyzed. Phenotypic evaluation revealed that only Bbbcs1b and Bbbcs1c contributed to fungal physiologies, and they localized to nuclei and mitochondria, respectively. Hence, Bbbcs1c is considered as the ortholog of yeast bcs1 in B. bassiana. Ablation of Bbbcs1c did not affect biogenesis of mitochondria, but its loss significantly attenuated mitochondrial functionality (e.g., ATP synthesis and mitochondrial targeting of proteins) significantly. ΔBbbcs1c mutant displayed the impaired phenotypes in vegetative growth, stress response, development, and virulence. Notably, ΔBbbcs1c mutant displayed the increased sensitivity to linoleic acid (LA) stress and lost the intracellular fatty acid homeostasis. The Bbbcs1c loss compromised the mitochondrial membrane potential, and LA stress exacerbated this damage. These findings indicate that Bbbcs1c is a functional homolog of yeast bcs1 in B. bassiana and links mitochondrial functionality to unique lifestyle in the entomopathogenic fungi.
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Affiliation(s)
- Jia Hou
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jin-Li Ding
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yue-Jin Peng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Ming-Guang Feng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Sheng-Hua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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Luo Z, Chen Q, Su Y, Hu S, Keyhani NO, Wang J, Zhu C, Zhou T, Pan Y, Bidochka MJ, Zhang Y. The AreA Nitrogen Catabolite Repression Activator Balances Fungal Nutrient Utilization and Virulence in the Insect Fungal Pathogen Beauveria bassiana. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:646-659. [PMID: 36584226 DOI: 10.1021/acs.jafc.2c07047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
In many fungi, the AreA GATA-type transcription factor mediates nitrogen catabolite repression affecting fungal development and, where applicable, virulence. Here, we investigated the functions of AreA in the fungal entomopathogen and plant endophyte Beauveria bassiana using knockdown of gene expression. The antiAreA mutants were impaired in nitrogen utilization and showed increased sensitivities to osmotic stressors but increased tolerances to oxidative/hypoxia stresses. Repression of BbAreA caused overall minimal effects on fungal virulence. The minor effects on virulence appeared to be due in part to competing secondary effects where host defense phenoloxidase activity was significantly decreased, but production of the fungal metabolite oosporein was increased and hyphal body development was impaired. Knockdown of BbAreA expression also resulted in impairment in ability of the fungus to associate with host plants. These data implicate that BbAreA likely acts as a regulator to balance fungal nutrient utilization, pathogenicity, and mutualism, facilitating the fungal occupation of host niches.
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Affiliation(s)
- Zhibing Luo
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Qiyan Chen
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Yufeng Su
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Shasha Hu
- Department of Biological Sciences, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - Nemat O Keyhani
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611, United States
| | - Junyao Wang
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Chenhua Zhu
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Teng Zhou
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Yunxia Pan
- College of Engineering and Technology, Southwest University, Chongqing 400715, P. R. China
| | - Michael J Bidochka
- Department of Biological Sciences, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - Yongjun Zhang
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
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Deng J, Lu Z, Wang H, Li N, Song G, Zhu Q, Sun J, Zhang Y. A secretory phospholipase A2 of a fungal pathogen contributes to lipid droplet homeostasis, assimilation of insect-derived lipids, and repression of host immune responses. INSECT SCIENCE 2022; 29:1685-1702. [PMID: 35276754 DOI: 10.1111/1744-7917.13029] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 02/21/2022] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
Secretory phospholipase A2s (sPLA2s) are found in a wide range of organisms from bacteria to higher plants and animals and are involved in varied and cellular processes. However, roles of these enzymes in microbial pathogens remain unclear. Here, an sPLA2 (BbPLA2) was characterized in the filamentous insect pathogenic fungus, Beauveria bassiana. BbPLA2 was exclusively expressed in insect hemolymph-derived cells (hyphal bodies), and its expression was induced by insect-derived nutrients and lipids, and nutrient starvation. High levels of secretion of BbPLA2 were observed as well as its distribution in hyphal body lipid drops (LDs). Overexpression of BbPLA2 increased the ability of B. bassiana to utilize insect-derived nutrients and lipids, and promoted LD accumulation, indicating functions for BbPLA2 in mediating LD homeostasis and assimilation of insect-derived lipids. Strains overexpressing BbPLA2 showed moderately increased virulence, including more efficient penetration of the insect cuticle and evasion of host immune responses as compared to the wild type strain. In addition, B. bassiana-activated host immune genes were downregulated in the BbPLA2 overexpression strain, but upregulated by infections with a ΔBbPLA2 strain. These data demonstrate that BbPLA2 contributes to LD homeostasis, assimilation of insect-derived lipids, and repression of host immune responses.
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Affiliation(s)
- Juan Deng
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Zhuoyue Lu
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Huifang Wang
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Ning Li
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Guimei Song
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Qiankuan Zhu
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- College of Plant Protection, Southwest University, Chongqing, China
| | - Jingxin Sun
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Yongjun Zhang
- Biotechnology Research Center, Academy of Agricultural Sciences, Southwest University, Chongqing, China
- College of Plant Protection, Southwest University, Chongqing, China
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20
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Succinate Dehydrogenase Subunit C Contributes to Mycelial Growth and Development, Stress Response, and Virulence in the Insect Parasitic Fungus Beauveria bassiana. Microbiol Spectr 2022; 10:e0289122. [PMID: 35972281 PMCID: PMC9602434 DOI: 10.1128/spectrum.02891-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Succinate dehydrogenase (SDH), also known as respiratory chain complex II, plays a crucial role in energy production in which SdhC functions as an anchored subunit in the inner membrane of mitochondria. In this study, domain annotation analyses revealed that two SdhC domain-containing proteins were present in the filamentous insect-pathogenic fungus Beauveria bassiana, and they were named BbSdhC1 and BbSdhC2, respectively. Only BbSdhC1 localized to mitochondria; hence, this protein is considered the ortholog of SdhC in B. bassiana. Ablation of BbSdhC1 led to significantly reduced vegetative growth on various nutrients. The ΔBbsdhc1 mutant displayed the significantly reduced ATP synthesis and abnormal differentiation under aerial and submerged conditions. Notably, the BbSdhC1 loss resulted in enhanced intracellular levels of reactive oxygen species (ROS) and impaired growth of mycelia under oxidative stress. Finally, insect bioassays (via cuticle and intrahemocoel injection infection) revealed that disruption of BbSdhC1 significantly attenuated fungal virulence against the insect hosts. These findings indicate that BbSdhC1 contributes to vegetative growth, resistance to oxidative stress, differentiation, and virulence of B. bassiana due to its roles in energy generation and maintaining the homeostasis of the intracellular ROS levels. IMPORTANCE The electron transport chain (ETC) is critical for energy supply by mediating the electron flow along the mitochondrial membrane. Succinate dehydrogenase (SDH) is also known as complex II in the ETC, in which SdhC is a subunit anchored in mitochondrial membrane. However, the physiological roles of SdhC remain enigmatic in filamentous fungi. In filamentous insect-pathogenic fungus B. bassiana, SdhC is required for maintaining mitochondrial functionality, which is critical for fungal stress response, development, and pathogenicity. These findings improve our understanding of physiological mechanisms of ETC components involved in pathogenicity of the entomopathogenic fungi.
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Bali GK, Singh SK, Chauhan VK, Joshi N, Bhat FA, Malla WA, Ramanujam B, Varshney R, Kour M, Pandit RS. An insight in proteome profiling of Tuta absoluta larvae after entomopathogenic fungal infection. Sci Data 2022; 9:507. [PMID: 35986033 PMCID: PMC9391459 DOI: 10.1038/s41597-022-01593-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 07/25/2022] [Indexed: 11/08/2022] Open
Abstract
Tuta absoluta (L.) (Lepidoptera: Gelechiidae), a major pest of solanaceous plant species, causes serious losses in the agriculture sector around the globe. For better pest management, entomopathogenic fungi such as Beauveria bassiana and Purpureocillium lilacinum, play an efficient role in suppressing the pest population. The present study was carried out to analyse the effects post fungal infections through proteome profiling using an Orbitrap Fusion Tribrid mass spectrometer. A total of 2,201 proteins were identified from the fourth instar larvae of T. absoluta, of which 442 and 423 proteins were significantly dysregulated upon infection with P. lilacinum and B. bassiana respectively. The potential proteins related to immune systems as well as detoxification processes showed significant alterations after post fungal infection. Studies on T. absoluta proteomics and genomics as well as the consequences of entomopathogenic fungal infection on the immune response of this insect could provide an initial framework for exploring more fungus-host interactions for the development of better strategies for integrated pest management.
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Affiliation(s)
- Gurmeet Kour Bali
- Department of Zoology, Savitribai Phule Pune University, Pune, 411007, India
| | - Sanjay Kumar Singh
- National Fungal Culture Collection of India, Biodiversity and Paleobiology Group, MACs Agharkar Research Institute, Pune, 411004, India
| | - Vinod Kumar Chauhan
- Department of Zoology, Visva-Bharati University, Santiniketan, 731235, India
| | - Neha Joshi
- Institute of Bioinformatics, International Technology Park, Bangalore, 560066, India
- Manipal Academy of Higher Education, MAHE, Manipal, 576104, India
| | - Firdous Ahmad Bhat
- Institute of Bioinformatics, International Technology Park, Bangalore, 560066, India
| | - Waseem Akram Malla
- Division of Veterinary Biotechnology ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, 243122, India
| | - Boman Ramanujam
- ICAR- National Bureau of Agricultural Insect Resources, Bengaluru-560024, Karnataka, India
| | - Richa Varshney
- ICAR- National Bureau of Agricultural Insect Resources, Bengaluru-560024, Karnataka, India
| | - Manpreet Kour
- Division of Veterinary Medicine, Faculty of Veterinary science and Animal Husbandry, S.K. University of Agricultural Sciences and Technology, R.S Pura, Jammu, 181102, India
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22
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The Elongator Subunit Elp3 Regulates Development, Stress Tolerance, Cell Cycle, and Virulence in the Entomopathogenic Fungus Beauveria bassiana. J Fungi (Basel) 2022; 8:jof8080834. [PMID: 36012822 PMCID: PMC9410351 DOI: 10.3390/jof8080834] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 01/01/2023] Open
Abstract
Transcriptional activity is mediated by chromatin remodeling, which in turn is affected by post-translational modifications, including histone acetylation. Histone acetyltransferases (HATs) are capable of promoting euchromatin formation and then activating gene transcription. Here, we characterize the Elp3 GNAT family HAT, which is also a subunit of Elongator complex, in the environmentally and economically important fungal insect pathogen, Beauveria bassiana. BbElp3 showed high localization levels to mitochondria, with some nuclear and cytoplasmic localization also apparent. Targeted gene knockout of BbElp3 resulted in impaired asexual development and morphogenesis, reduced tolerances to multiple stress conditions, reduced the ability of the fungus to utilize various carbon/nitrogen sources, increased susceptibility to rapamycin, and attenuated virulence in bioassays using the greater wax moth, Galleria mellonella. The ΔBbElp3 mutant also showed disrupted cell cycle, abnormal hyphal septation patterns, and enlarged autophagosomes in vegetative hyphae. Transcriptome analyses revealed differential expression of 775 genes (DEGs), including 336 downregulated and 438 upregulated genes in the ΔBbElp3 strain as compared to the wild type. Downregulated genes were mainly enriched in pathways involved in DNA processing and transcription, cell cycle control, cellular transportation, cell defense, and virulence, including hydrophobins, cellular transporters (ABC and MFS multidrug transporters), and insect cuticular degrading enzymes, while upregulated genes were mainly enriched in carbohydrate metabolism and amino acid metabolism. These data indicate pleiotropic effects of BbElp3 in impacting specific cellular processes related to asexual development, cell cycle, autophagy, and virulence.
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Wang JL, Yang KH, Wang SS, Li XL, Liu J, Yu YX, Liu XS. Infection of the entomopathogenic fungus Metarhizium rileyi suppresses cellular immunity and activates humoral antibacterial immunity of the host Spodoptera frugiperda. PEST MANAGEMENT SCIENCE 2022; 78:2828-2837. [PMID: 35394109 DOI: 10.1002/ps.6907] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 04/02/2022] [Accepted: 04/08/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Metarhizium rileyi is an entomopathogenic fungus with promising potential for controlling agricultural pests, including Spodoptera frugiperda. Following penetration of the host through the cuticle, M. rileyi cells transform into in vivo blastospores or hyphal bodies, propagating within the hemocoel. However, the strategies and molecular mechanisms by which M. rileyi survives upon exposure to the powerful insect immune system remain unclear. RESULTS We determined the pathogenicity of M. rileyi and found that either conidial immersion or blastospore injection significantly decreased S. frugiperda survival in a dose-dependent manner. Injection of M. rileyi blastospores decreased the number of S. frugiperda hemocytes and impaired host cellular reactions such as nodulation, encapsulation and phagocytosis. Blastospore injection led to increased antibacterial activity in plasma at 48 h post-injection (hpi). RNA-sequencing analyses identified a large number of antimicrobial peptide genes upregulated in the fat body of M. rileyi-infected larvae at 48 hpi, which may be attributable to the activation of Toll and IMD signaling pathway. CONCLUSION This study demonstrates that the compromised cellular immunity of the insect host is due to the marked decrease in hemocytes and impaired cellular cytoskeletons, which may facilitate early infection by M. rileyi. Late in the course of infection, the enhanced antibacterial activity of plasma, which may be in response to intestinal evading bacteria, cannot inhibit hyphal growth in hemolymph. Our data provide a comprehensive resource for exploring the molecular mechanism employed by M. rileyi to overcome S. frugiperda immunity. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Jia-Lin Wang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Ke-Hui Yang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Si-Si Wang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Xin-Lin Li
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Jie Liu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Ye-Xin Yu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Xu-Sheng Liu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
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24
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Differential Roles of Three α-Crystallin Domain-Containing sHsps of Beauveria bassiana in Asexual Development, Multiple Stress Tolerance and Virulence. Int J Mol Sci 2022; 23:ijms23126717. [PMID: 35743166 PMCID: PMC9224193 DOI: 10.3390/ijms23126717] [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: 04/27/2022] [Revised: 06/11/2022] [Accepted: 06/14/2022] [Indexed: 12/10/2022] Open
Abstract
Small heat shock proteins (sHsps) containing conserved α-crystallin domain play important roles in many cellular processes, but little is known about the functions of sHsps in filamentous entomopathogens. Here, three sHsps of Hsp20, Hsp30a, and Hsp30b were characterized in Beauveria bassiana, a filamentous fungal insect pathogen that serves as the main source of wide-spectrum fungal insecticides. The results demonstrated that these three genes are interrelated at the transcriptional level under normal and heat-shocked conditions. Meanwhile, all the deletion mutants showed significant but differential changes in cell wall integrity, antioxidant activity, hyphal tolerance to carbendazim fungicide, conidial tolerance to 45 °C wet heat and virulence. However, only Δhsp30b showed growth defects on rich and minimal media at 25 °C and Δhsp30a displayed the reduction in conidiophores and conidia. Moreover, the single deletion of hsp30a and hsp30b caused the decreases in hyphal growth at 34 °C and conidial tolerance to UV-B irradiation. Our findings provide a global insight into vital roles of hsp20, hsp30a, and hsp30b in asexual development, environmental adaptation, and fungal virulence of B. bassiana.
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25
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A Perilipin Affects Lipid Droplet Homeostasis and Aerial Hyphal Growth, but Has Only Small Effects on Virulence in the Insect Pathogenic Fungus Beauveria bassiana. J Fungi (Basel) 2022; 8:jof8060634. [PMID: 35736117 PMCID: PMC9225014 DOI: 10.3390/jof8060634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/08/2022] [Accepted: 06/08/2022] [Indexed: 02/04/2023] Open
Abstract
Lipid assimilation, storage, and turnover impact growth, development, and virulence in many microbial pathogens including fungi. Perilipins are proteins associated with lipid droplets (LDs) that mediate their assembly and turnover. Here, we characterized the Beauveria bassiana (BbPlin1) perilipin. BbPlin1 expression was higher in minimal media than in rich media, and, using a BbPlin1::eGFP fusion protein, the protein was shown to be co−localized to LDs, with the high expression seen during infection and proliferation within the insect (Galleria mellonella) host that dramatically decreased to almost no expression during fungal outgrowth on cadavers including in conidia, but that BbPlin1 production resumed in the conidia once placed in nutrient−containing media allowing for germination and growth. Characterization of a targeted gene deletion strain (ΔBbPlin1) revealed a dramatic (>30%) reduction in cellular LD content, promotion of aerial hyphal growth, and a small decrease in virulence, with little to no effects on vegetative growth and stress responses. However, in the ΔBbPlin1 strain, expression of the complementary LD−associated caleosin gene, BbCal1, was enhanced under nutrient−poor conditions, although no changes in BbPlin1 expression were seen in a ΔBbCal1 strain and the expression of BbPlin1 in the ΔBbCal1 strain did not change LD patterns in cells. Transcriptome and RT−PCR analyses indicated increased expression of lipid metabolism−related genes, including triacylglyercol lipase 3, enoyl−CoA isomerase, and diacylglycerol−O−acetyl transferase in the BbPlin1 deletion mutant. Lipid profile analyses confirmed that the loss of BbPlin1 significantly reduced the cellular levels of contents of triacylglycerol, diacylglycerol, and phosphatidylethanolamine as compared to the wild−type strain. These results demonstrate the involvement of the B. bassiana perilipin in mediating lipid homeostasis, fungal aerial hyphal growth, and virulence, revealing critical cycling from high expression during nutrient utilization within host cadavers to low expression during growth on the surface of the cadaver during the infection process.
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26
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Hou J, Lin H, Ding J, Feng M, Ying S. Peroxins in Peroxisomal Receptor Export System Contribute to Development, Stress Response, and Virulence of Insect Pathogenic Fungus Beauveria bassiana. J Fungi (Basel) 2022; 8:622. [PMID: 35736105 PMCID: PMC9224678 DOI: 10.3390/jof8060622] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 06/02/2022] [Accepted: 06/07/2022] [Indexed: 02/06/2023] Open
Abstract
In filamentous fungi, recycling of receptors responsible for protein targeting to peroxisomes depends on the receptor export system (RES), which consists of peroxins Pex1, Pex6, and Pex26. This study seeks to functionally characterize these peroxins in the entomopathogenic fungus Beauveria bassiana. BbPex1, BbPex6, and BbPex26 are associated with peroxisomes and interact with each other. The loss of these peroxins did not completely abolish the peroxisome biogenesis. Three peroxins were all absolutely required for PTS1 pathway; however, only BbPex6 and BbPex26 were required for protein translocation via PTS2 pathway. Three gene disruption mutants displayed the similar phenotypic defects in assimilation of nutrients (e.g., fatty acid, protein, and chitin), stress response (e.g., oxidative and osmotic stress), and virulence. Notably, all disruptant displayed significantly enhanced sensitivity to linoleic acid, a polyunsaturated fatty acid. This study reinforces the essential roles of the peroxisome in the lifecycle of entomopathogenic fungi and highlights peroxisomal roles in combating the host defense system.
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Affiliation(s)
| | | | | | | | - Shenghua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China; (J.H.); (H.L.); (J.D.); (M.F.)
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Endophytic blastospores of Beauveria bassiana provide high resistance against plant disease caused by Botrytis cinerea. Fungal Biol 2022; 126:528-533. [DOI: 10.1016/j.funbio.2022.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 05/20/2022] [Accepted: 05/26/2022] [Indexed: 11/20/2022]
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28
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Peng YJ, Hou J, Zhang H, Lei JH, Lin HY, Ding JL, Feng MG, Ying SH. Systematic contributions of CFEM domain-containing proteins to iron acquisition are essential for interspecies interaction of the filamentous pathogenic fungus Beauveria bassiana. Environ Microbiol 2022; 24:3693-3704. [PMID: 35523457 DOI: 10.1111/1462-2920.16032] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/13/2022] [Accepted: 04/25/2022] [Indexed: 11/29/2022]
Abstract
Common in fungal extracellular membrane (CFEM) domain is unique in fungal proteins and some of which contribute to iron acquisition in yeast. However, their roles in iron acquisition remain largely unknown in filamentous fungi. In this study, 12 CFEM-containing proteins were bioinformatically identified in the filamentous entomopathogenic fungus Beauveria bassiana, and the roles of 11 genes were genetically characterized. Transmembrane helices were critical for their association with intracellular membranes, and their number varied among proteins. Eleven CFEM genes significantly contribute to vegetative growth under iron starvation and virulence. Notably, the virulence of most disruptants could be significantly weakened by a decrease in iron availability, in which the virulence of ΔBbcfem7 and 8 strains was partially recovered by exogenous hemin. ΔBbcfem7 and 8 mutants displayed defective competitiveness against the sister entomopathogenic fungus Beauveria brongniartii. All 11 disruptants displayed impaired growth in the antagonistic assay with the saprotrophic fungus Aspergillus niger, which could be repressed by exogenous ferric ions. These findings not only reveal the systematic contributions of CFEM proteins to acquire two forms of iron (i.e. heme and ferric ion) in the entire lifecycle of entomopathogenic fungi but also help to better understand the mechanisms of fungus-host and inter-fungus interactions.
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Affiliation(s)
- Yue-Jin Peng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Jia Hou
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Hao Zhang
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Jia-Hui Lei
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Hai-Yan Lin
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Jin-Li Ding
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Ming-Guang Feng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Sheng-Hua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
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29
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Peng YJ, Zhang H, Feng MG, Ying SH. Steryl Acetyl Hydrolase 1 (BbSay1) Links Lipid Homeostasis to Conidiogenesis and Virulence in the Entomopathogenic Fungus Beauveria bassiana. J Fungi (Basel) 2022; 8:jof8030292. [PMID: 35330294 PMCID: PMC8953178 DOI: 10.3390/jof8030292] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 02/06/2023] Open
Abstract
Beauveria bassiana, as a well-studied entomopathogenic fungus, has a great potential for the biological control of insect pests. Lipid metabolism has been linked to the life cycle of B. bassiana; however, the underlying mechanisms remain unknown. In this study, a homolog of yeast steryl acetyl hydrolase 1 (Say1) was functionally characterized. The loss of B. bassianaSAY1 (BbSAY1) impaired the lipid homeostasis in conidia, with a significant reduction in oleic acid content. The ΔBbsay1 mutant strain displayed anelevated accumulation of lipid bodies and aweakened membrane permeability. As for phenotypic aspects, gene loss resulted in significant defects in germination, conidiation, and virulence. Our findings highlight that Say1, involved in lipid homeostasis, contributes to the cytomembrane integrity, development, and virulence in B. bassiana.
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30
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Cai Q, Tian L, Xie JT, Jiang DH, Keyhani NO. Contributions of a Histone Deacetylase (SirT2/Hst2) to Beauveria bassiana Growth, Development, and Virulence. J Fungi (Basel) 2022; 8:jof8030236. [PMID: 35330238 PMCID: PMC8950411 DOI: 10.3390/jof8030236] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 02/25/2022] [Accepted: 02/25/2022] [Indexed: 02/05/2023] Open
Abstract
Sirtuins are a class of histone deacetylases that promote heterochromatin formation to repress transcription. The entomopathogenic fungus Beauveria bassiana contains six sirtuin homologs. The class III histone deacetylase, BbSir2, has been previously shown to affect the regulation of carbon/nitrogen metabolism and asexual development, with only moderate effects on virulence. Here, we examine another class III histone deacetylase (BbSirT2) and show that it contributes to deacetylation of lysine residues on histone H4-K16ac. Directed gene-knockout of BbSirT2 dramatically reduced conidiation, the ability of the fungus to metabolize a range of carbon and nitrogen sources, and tolerances to oxidative, heat, and UV stress and significantly attenuated virulence in both intrahemocoel injection and topical bioassays using the Greater wax moth (Galleria mellonella) as the insect host. ΔBbSirT2 cells showed alterations in cell cycle development and hyphal septation and produced morphologically aberrant conidia. Comparative transcriptomic analyses of wild type versus ΔBbSirT2 cells indicated differential expression of 1148 genes. Differentially expressed genes were enriched in pathways involved in cell cycle and rescue, carbon/nitrogen metabolism, and pathogenesis. These included changes in the expression of polyketide synthases (PKSs) and LysM effector proteins that contribute to degradation of host toxins and target host pathways, respectively. These data indicate contributions of BbSirT2 in helping to mediate fungal stress and development, with the identification of affected gene targets that can help account for the observed reduced virulence phenotype.
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Affiliation(s)
- Qing Cai
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (J.-T.X.); (D.-H.J.)
- Department of Microbiology and Cell Science, University of Florida, Bldg. 981, Museum Rd., Gainesville, FL 32611, USA
- Correspondence: (Q.C.); (N.O.K.)
| | - Li Tian
- Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology, Jinan 250353, China;
| | - Jia-Tao Xie
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (J.-T.X.); (D.-H.J.)
| | - Dao-Hong Jiang
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (J.-T.X.); (D.-H.J.)
| | - Nemat O. Keyhani
- Department of Microbiology and Cell Science, University of Florida, Bldg. 981, Museum Rd., Gainesville, FL 32611, USA
- Correspondence: (Q.C.); (N.O.K.)
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Omuse ER, Niassy S, Wagacha JM, Ong’amo GO, Lattorff HMG, Kiatoko N, Mohamed SA, Subramanian S, Akutse KS, Dubois T. Susceptibility of the Western Honey Bee Apis mellifera and the African Stingless Bee Meliponula ferruginea (Hymenoptera: Apidae) to the Entomopathogenic Fungi Metarhizium anisopliae and Beauveria bassiana. JOURNAL OF ECONOMIC ENTOMOLOGY 2022; 115:46-55. [PMID: 35139218 PMCID: PMC8827312 DOI: 10.1093/jee/toab211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Indexed: 06/14/2023]
Abstract
This study assessed the nontarget effect of entomopathogenic fungi on the Western honey bee Apis mellifera L. and the African stingless bee Meliponula ferruginea Cockrell (Hymenoptera: Apidae). Pathogenicity of five Metarhizium anisopliae (ICIPE 7, ICIPE 20, ICIPE 62, ICIPE 69, and ICIPE 78) (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae) and one of Beauveria bassiana (ICIPE 284) (Balsamo) Vuillemin (Hypocreales: Cordicipitaceae) isolates were evaluated on bees at 108 conidia/ml. Conidial acquisition was evaluated immediately after exposure. Apis mellifera acquired more conidia (2.8 × 104-1.3 × 105 conidia per bee) compared to M. ferruginea (1.1 × 104-2.3 × 104 conidia per bee). In the bioassay with A. mellifera, ICIPE 7, ICIPE 20, and ICIPE 69 moderately reduced the survival by 16.9, 17.4, 15.3%, with lethal times LT10 = 7.4, 7.6, 8.1 d and LT25 = 8.7, 10.0, 9.9 d, respectively. The three isolates caused A. mellifera mycosis of 11.6-18.5%. None of the isolates had a significant effect on M. ferruginea. The tested isolates are nontoxic to bees according to the International Organization of Biological Control (IOBC) classification. However, the effect of ICIPE 7, ICIPE 20, and ICIPE 69 merits further studies on bee colonies, especially those of A. mellifera, under field conditions.
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Affiliation(s)
- Evanson R Omuse
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- School of Biological Sciences, University of Nairobi, Nairobi, Kenya
| | - Saliou Niassy
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - John M Wagacha
- School of Biological Sciences, University of Nairobi, Nairobi, Kenya
| | - George O Ong’amo
- School of Biological Sciences, University of Nairobi, Nairobi, Kenya
| | | | - Nkoba Kiatoko
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Samira A Mohamed
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Sevgan Subramanian
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Komivi S Akutse
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Thomas Dubois
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
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Abstract
The entomopathogenic fungus Beauveria bassiana is a typical filamentous fungus and has been used for pest biocontrol. Conidia are the main active agents of fungal pesticides; however, we know little about conidial developmental mechanisms and less about maturation mechanisms. We found that a Zn2Cys6 transcription factor of B. bassiana (named BbCmr1) was mainly expressed in late-stage conidia and was involved in conidium maturation regulation. Deletion of Bbcmr1 impaired the conidial cell wall and resulted in a lower conidial germination rate under UV (UV), heat shock, H2O2, Congo red (CR) and SDS stresses compared to the wild type. Transcription levels of the genes associated with conidial wall components and trehalose synthase were significantly reduced in the ΔBbcmr1 mutant. Further analysis found that BbCmr1 functions by upregulating BbWetA, a well-known transcription factor in the central development of BrlA-AbaA-WetA. The expression of Bbcmr1 was positively regulated by BbBrlA. These results indicated that BbCmr1 played important roles in conidium maturation by interacting with the central development pathway, which provided insight into the conidial development networks in B. bassiana. IMPORTANCE Conidium maturation is a pivotal event in conidial development and affects fungal survival ability under various biotic/abiotic stresses. Although many transcription factors have been reported to regulate conidial development, we know little about the molecular mechanism of conidium maturation. Here, we demonstrated that the transcription factor BbCmr1 of B. bassiana was involved in conidium maturation, regulating cell wall structure, the expression of cell wall-related proteins, and trehalose synthesis. BbCmr1 orchestrated conidium maturation by interplaying with the central development pathway BrlA-AbaA-WetA. BbBrlA positively regulated the expression of Bbcmr1, and the latter positively regulated BbwetA expression, which forms a regulatory network mediating conidial development. This finding was critical to understand the molecular regulatory networks of conidial development in B. bassiana and provided avenues to engineer insect fungal pathogens with high-quality conidia.
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Fiorotti J, Urbanová V, Gôlo PS, Bittencourt VREP, Kopáček P. The role of complement in the tick cellular immune defense against the entomopathogenic fungus Metarhizium robertsii. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2022; 126:104234. [PMID: 34450130 DOI: 10.1016/j.dci.2021.104234] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 08/16/2021] [Accepted: 08/16/2021] [Indexed: 06/13/2023]
Abstract
Entomopathogenic fungi (EPF) have been widely explored for their potential in the biological control of insect pests and as an environmentally friendly alternative to acaricides for limiting tick infestation in the field. The arthropod cuticle is the main barrier against fungal infection, however, an understanding of internal defense mechanisms after EPF intrusion into the invertebrate hemocoel is still rather limited. Using an infection model of the European Lyme borreliosis vector Ixodes ricinus with the EPF Metarhizium robertsii, we demonstrated that ticks are capable of protecting themselves to a certain extent against mild fungal infections. However, tick mortality dramatically increases when the capability of tick hemocytes to phagocytose fungal conidia is impaired. Using RNAi-mediated silencing of tick thioester-containing proteins (TEPs), followed by in vitro and/or in vivo phagocytic assays, we found that C3-like complement components and α2-macroglobulin pan-protease inhibitors secreted to the hemolymph play pivotal roles in M. robertsii phagocytosis.
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Affiliation(s)
- Jéssica Fiorotti
- Programa de Pós-Graduação Em Ciências Veterinárias, Instituto de Veterinária, Universidade Federal Rural Do Rio de Janeiro, Seropédica, Brazil
| | - Veronika Urbanová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, CZ-370 05, Czech Republic
| | - Patrícia Silva Gôlo
- Programa de Pós-Graduação Em Ciências Veterinárias, Instituto de Veterinária, Universidade Federal Rural Do Rio de Janeiro, Seropédica, Brazil
| | | | - Petr Kopáček
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, CZ-370 05, Czech Republic.
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Baioumy AA, Swelim HH, Ibrahim AA, Mohamed FES, Marzouk AS, El-Alfy SH. Acaricidal and pathogenic effects of the entomopathogenic fungus Beauveria bassiana on engorged females of the fowl tick, Argas persicus (Argasidae). EXPERIMENTAL & APPLIED ACAROLOGY 2021; 85:331-354. [PMID: 34751842 DOI: 10.1007/s10493-021-00671-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
This study examined the acaricidal, histopathological and genotoxic effects of the entomopathogenic fungus Beauveria bassiana on engorged females of the fowl tick, Argas persicus. The acaricidal effect of B. bassiana (at 106-1010 conidia/mL) was concentration- and time-dependent. At 106 conidia/mL, the accumulated mortality of treated females ranged from 3.33 ± 3.3 to 13.33 ± 3.3% over 21 days. However, the mortality was remarkably increased after the application of 1010 conidia/mL, ranging from 6.67 ± 3.3 to 80 ± 5.8%. Females treated with various conidial concentrations exhibited complete inhibition of oviposition. Light and electron microscopic examination of the ovary of engorged female ticks at 3, 6 and 9 days after treatment with 107 conidia/mL revealed that the oocytes exhibited drastic changes that affected their growth and development. The overall damage observed in the ovary included loss of grape-like appearance, distortion of oocytes, cytoplasmic vacuolation, degeneration of organelles and myelin figure formation. Previtellogenic oocyte progression was completely inhibited as the vitellogenic phase was not observed. Random amplified polymorphic DNA (RAPD-PCR) and inter simple sequence repeat (ISSR) methods were used to assess the genotoxic effects of B. bassiana at 107 conidia/mL on engorged female A. persicus over 3 weeks. The lowest percentage of genomic template stability was recorded in paralyzed ticks after 3 weeks. The study demonstrated the efficacy of B. bassiana as a biocontrol agent against A. persicus as it interfered with its reproduction, movement and viability and disrupted its normal tissue and DNA integrity.
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Affiliation(s)
- Asmaa Ali Baioumy
- Department of Zoology, Faculty of Science, Ain Shams University, Cairo, Egypt
| | - Hamdy Hamed Swelim
- Department of Zoology, Faculty of Science, Ain Shams University, Cairo, Egypt
| | - Ahmed Adly Ibrahim
- Bioinsecticides Production Unit, Plant Protection Research Institute, Agriculture Research Center, Giza, Egypt
| | | | | | - Sherif Helmy El-Alfy
- Department of Zoology, Faculty of Science, Ain Shams University, Cairo, Egypt.
- Department of Biology, College of Science, Taibah University, Almadina Almunawara, Saudi Arabia.
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Peng YJ, Ding JL, Lin HY, Feng MG, Ying SH. A virulence-related lectin traffics into eisosome and contributes to functionality of cytomembrane and cell-wall in the insect-pathogenic fungus Beauveria bassiana. Fungal Biol 2021; 125:914-922. [PMID: 34649678 DOI: 10.1016/j.funbio.2021.06.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/29/2021] [Accepted: 06/12/2021] [Indexed: 11/25/2022]
Abstract
Lectins are characterized of the carbohydrate-binding ability and play comprehensive roles in fungal physiology (e.g., defense response, development and host-pathogen interaction). Beauveria bassiana, a filamentous entomopathogenic fungus, has a lectin-like protein containing a Fruit Body_domain (BbLec1). BbLec1 could bind to chitobiose and chitin in fungal cell wall. BbLec1 proteins interacted with each other to form multimers, and translocated into eisosomes. Further, the interdependence between BbLec1 and the eisosome protein PliA was essential for stabilizing the eisosome architecture. To test the BbLec1 roles in B. bassiana, we constructed the gene disruption and complementation mutants. Notably, the BbLec1 loss resulted in the impaired cell wall in mycelia and conidia as well as conidial formation capacity. In addition, disruption of BbLec1 led to the reduced cytomembrane integrity and the enhanced sensitivity to osmotic stress. Finally, ΔBbLec1 mutant strain displayed the weakened virulence when compared with the wild-type strain. Taken together, BbLec1 traffics into eisosome and links the functionality of eisosome to development and virulence of B. bassiana.
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Affiliation(s)
- Yue-Jin Peng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Jin-Li Ding
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Hai-Yan Lin
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Ming-Guang Feng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Sheng-Hua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
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Wang H, Peng H, Li W, Cheng P, Gong M. The Toxins of Beauveria bassiana and the Strategies to Improve Their Virulence to Insects. Front Microbiol 2021; 12:705343. [PMID: 34512581 PMCID: PMC8430825 DOI: 10.3389/fmicb.2021.705343] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/27/2021] [Indexed: 01/18/2023] Open
Abstract
The long-term and excessive usage of pesticides is an enormous burden on the environment, which also increases pest resistance. To overcome this problem, research and application of entomopathogenic fungi, which are both environmentally friendly and cause lower resistance, have gained great momentum. Entomopathogenic fungi have a wide range of prospects. Apart from Bacillus thuringiensis, Beauveria bassiana is the most studied biopesticide. After invading insect hosts, B. bassiana produces a variety of toxins, which are secondary metabolites such as beauvericin, bassianin, bassianolide, beauverolides, tenellin, oosporein, and oxalic acid. These toxins help B. bassiana to parasitize and kill the hosts. This review unequivocally considers beauveria toxins highly promising and summarizes their attack mechanism(s) on the host insect immune system. Genetic engineering strategies to improve toxin principles, genes, or virulent molecules of B. bassiana have also been discussed. Lastly, we discuss the future perspective of Beauveria toxin research, including newly discovered toxins.
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Affiliation(s)
- Haiyang Wang
- Shandong Institute of Parasitic Diseases, Shandong First Medical University & Shandong Academy of Medical Sciences, Jining, China.,College of Forensic Medicine and Laboratory Medicine, Jining Medical University, Jining, China
| | - Hui Peng
- Shandong Institute of Parasitic Diseases, Shandong First Medical University & Shandong Academy of Medical Sciences, Jining, China
| | - Wenjuan Li
- College of Forensic Medicine and Laboratory Medicine, Jining Medical University, Jining, China
| | - Peng Cheng
- Shandong Institute of Parasitic Diseases, Shandong First Medical University & Shandong Academy of Medical Sciences, Jining, China
| | - Maoqing Gong
- Shandong Institute of Parasitic Diseases, Shandong First Medical University & Shandong Academy of Medical Sciences, Jining, China
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Qiu L, Zhang TS, Song JZ, Zhang J, Li Z, Wang JJ. BbWor1, a Regulator of Morphological Transition, Is Involved in Conidium-Hypha Switching, Blastospore Propagation, and Virulence in Beauveria bassiana. Microbiol Spectr 2021; 9:e0020321. [PMID: 34319134 PMCID: PMC8552717 DOI: 10.1128/spectrum.00203-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/07/2021] [Indexed: 12/16/2022] Open
Abstract
Morphological transition is an important adaptive mechanism in the host invasion process. Wor1 is a conserved fungal regulatory protein that controls the phenotypic switching and pathogenicity of Candida albicans. By modulating growth conditions, we simulated three models of Beauveria bassiana morphological transitions, including CTH (conidia to hyphae), HTC (hyphae to conidia), and BTB (blastospore to blastospore). Disruption of BbWor1 (an ortholog of Wor1) resulted in a distinct reduction in the time required for conidial germination (CTH), a significant increase in hyphal growth, and a decrease in the yield of conidia (HTC), indicating that BbWor1 positively controls conidium production and negatively regulates hyphal growth in conidium-hypha switching. Moreover, ΔBbWor1 prominently decreased blastospore yield, shortened the G0/G1 phase, and prolonged the G2/M phase under the BTB model. Importantly, BbWor1 contributed to conidium-hypha switching and blastospore propagation via different genetic pathways, and yeast one-hybrid testing demonstrated the necessity of BbWor1 to control the transcription of an allergen-like protein gene (BBA_02580) and a conidial wall protein gene (BBA_09998). Moreover, the dramatically weakened virulence of ΔBbWor1 was examined by immersion and injection methods. Our findings indicate that BbWor1 is a vital participant in morphological transition and pathogenicity in entomopathogenic fungi. IMPORTANCE As a well-known entomopathogenic fungus, Beauveria bassiana has a complex life cycle and involves transformations among single-cell conidia, blastospores, and filamentous hyphae. This study provides new insight into the regulation of the fungal cell morphological transitions by simulating three models. Our research identified BbWor1 as a core transcription factor of morphological differentiation that positively regulates the production of conidia and blastospores but negatively regulates hyphal growth. More importantly, BbWor1 affects fungal pathogenicity and the global transcription profiles within three models of growth stage transformation. The present study lays a foundation for the exploration of the transition mechanism of entomopathogenic fungi and provides material for the morphological study of fungi.
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Affiliation(s)
- Lei Qiu
- School of Biological Science and Technology, University of Jinan, Jinan, China
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan, China
| | - Tong-Sheng Zhang
- School of Biological Science and Technology, University of Jinan, Jinan, China
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan, China
| | - Ji-Zheng Song
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan, China
| | - Jing Zhang
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan, China
| | - Ze Li
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan, China
| | - Juan-Juan Wang
- School of Biological Science and Technology, University of Jinan, Jinan, China
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Ding JL, Hou J, Feng MG, Ying SH. Transcriptomic analyses reveal comprehensive responses of insect hemocytes to mycopathogen Beauveria bassiana, and fungal virulence-related cell wall protein assists pathogen to evade host cellular defense. Virulence 2021; 11:1352-1365. [PMID: 33017218 PMCID: PMC7549920 DOI: 10.1080/21505594.2020.1827886] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Entomopathogenic fungi naturally infect insect hosts in environment. Fungal invasion and host immune defense are still in the progress of co-evolution. In this study, entomopathogenic fungus Beauveria bassiana and lepidopteran insect Galleria mellonella were used to investigate host cellular immunity and fungal strategy to evade host defense. First of all, genome-wide expression revealed the transcriptomic responses of hemocytes to insect mycopathogen, which dynamically varied during infection process. Enrichment analysis indicated that differentially expressed genes were primarily involved in metabolism, cellular process and immune system. Notably, cellular response involved a series of hydrolytic enzyme and antimicrobial peptide genes which were sorted together in clustering analysis. In B. bassiana, a cell-wall protein gene (BbCwp) contributes to fungal development in host hemocoel and virulence. RT-qPCR analyses indicated that infection by ΔBbCwp mutant strain caused the up-regulated expression of a series of immunity-related genes, including β-1, 3-glucan recognition protein, hydrolytic enzyme and antimicrobial peptide genes. Disruption of BbCwp resulted in a significant change in conidial lectin-binding feature and the enhanced encapsulation by the host hemocytes. After being treated with hydrolytic enzymes, ΔBbCwp mutant displayed a significantly enhanced sensitivity to osmotic and oxidative stresses. In conclusion, fungal invasion initiates comprehensive physiological responses in the host hemocytes. For mycopathogen, cell-wall protein plays an important role in fungal evasion of immunity defense and colonization in host. Our studies provide an initial framework for exploring more mechanistic details about the fungus–host interaction.
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Affiliation(s)
- Jin-Li Ding
- Institute of Microbiology, College of Life Sciences, Zhejiang University , Hangzhou, China
| | - Jia Hou
- Institute of Microbiology, College of Life Sciences, Zhejiang University , Hangzhou, China
| | - Ming-Guang Feng
- Institute of Microbiology, College of Life Sciences, Zhejiang University , Hangzhou, China
| | - Sheng-Hua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University , Hangzhou, China
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Pang MY, Lin HY, Hou J, Feng MG, Ying SH. Different contributions of the peroxisomal import protein Pex5 and Pex7 to development, stress response and virulence of insect fungal pathogen Beauveria bassiana. J Appl Microbiol 2021; 132:509-519. [PMID: 34260798 DOI: 10.1111/jam.15216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 07/09/2021] [Accepted: 07/13/2021] [Indexed: 11/27/2022]
Abstract
AIMS Peroxins Pex5 and Pex7 belong to the peroxisomal import machinery and recognize proteins containing peroxisomal targeting signal (PTS) type 1 and type 2, respectively. This study seeks to characterize these two peroxins in the entomopathogenic fungus Beauveria bassiana. METHODS AND RESULTS The orthologs of Pex5 and Pex7 in B. bassiana (BbPex5 and BbPex7) were functionally analyzed via protein localization and gene disruption. BbPex5 and BbPex7 were associated with peroxisome and specifically required for PTS1 and PTS2 pathways, respectively, which were demonstrated to be involved in development, tolerance to oxidative stress and virulence. ΔBbPex5 mutant displayed additionally defectives that were undetected in ΔBbPex7 in vegetative growth and resistance to osmotic and cell wall-perturbing stresses. Notably, Woronin body major protein Hex1 with PTS1 linked this organelle to the development and virulence of B. bassiana, which indicates that Woronin body is associated with the roles of PTS1 pathway. CONCLUSION Both PTS1 and PTS2 pathways are involved in broad physiological process, and the PTS1 pathway acts as a main peroxisomal import pathway. SIGNIFICANCE AND IMPACT OF THE STUDY This study shows the functional divergence of different peroxins and improves our understanding of organellar physiology involved in biocontrol potential of the entomopathogenic fungi.
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Affiliation(s)
- Meei-Yuan Pang
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Hai-Yan Lin
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Jia Hou
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Ming-Guang Feng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Sheng-Hua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
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Li C, Zhang Q, Xia Y, Jin K. MaAreB, a GATA Transcription Factor, Is Involved in Nitrogen Source Utilization, Stress Tolerances and Virulence in Metarhizium acridum. J Fungi (Basel) 2021; 7:jof7070512. [PMID: 34198996 PMCID: PMC8305397 DOI: 10.3390/jof7070512] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/24/2021] [Accepted: 06/24/2021] [Indexed: 01/14/2023] Open
Abstract
The nitrogen catabolite repression (NCR) pathway is involved in nitrogen utilization, in which the global GATA transcription factor AreA plays an indispensable role and has been reported in many fungi. However, relatively few studies are focused on AreB, another GATA transcription factor in the NCR pathway and the functions of AreB are largely unknown in entomopathogenic fungi. Here, we characterized MaAreB in the model entomopathogenic fungus Metarhizium acridum. Sequence arrangement found that MaAreB had a conserved GATA zinc finger DNA binding domain and a leucine zipper domain. Disruption of MaAreB affected the nitrogen utilization and led to decelerated conidial germination and hyphal growth, decreased conidial yield, and lower tolerances to UV-B irradiation and heat-shock. Furthermore, the MaAreB mutant (ΔMaAreB) exhibited increased sensitivity to CFW (Calcofluor white), decreased cell wall contents (chitin and β-1,3-glucan) and reduced expression levels of some genes related to cell wall integrity, indicating that disruption of MaAreB affected the cell wall integrity. Bioassays showed that the virulence of the ΔMaAreB strain was decreased in topical inoculation but not in intra-hemocoel injection. Consistently, deletion of MaAreB severely impaired the appressorium formation and reduced the turgor pressure of appressorium. These results revealed that MaAreB regulated fungal nitrogen utilization, cell wall integrity and biological control potential, which would contribute to the functional characterization of AreB homologous proteins in other insect fungal pathogens, and even filamentous fungi.
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Affiliation(s)
- Chaochuang Li
- Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing 401331, China; (C.L.); (Q.Z.)
- Chongqing Engineering Research Center for Fungal Insecticide, Chongqing 401331, China
- Key Laboratory of Gene Function and Regulation Technologies Under Chongqing Municipal Education Commission, Chongqing 401331, China
| | - Qipei Zhang
- Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing 401331, China; (C.L.); (Q.Z.)
- Chongqing Engineering Research Center for Fungal Insecticide, Chongqing 401331, China
- Key Laboratory of Gene Function and Regulation Technologies Under Chongqing Municipal Education Commission, Chongqing 401331, China
| | - Yuxian Xia
- Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing 401331, China; (C.L.); (Q.Z.)
- Chongqing Engineering Research Center for Fungal Insecticide, Chongqing 401331, China
- Key Laboratory of Gene Function and Regulation Technologies Under Chongqing Municipal Education Commission, Chongqing 401331, China
- Correspondence: (Y.X.); (K.J.); Tel.: +86-23-65120990 (Y.X.)
| | - Kai Jin
- Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing 401331, China; (C.L.); (Q.Z.)
- Chongqing Engineering Research Center for Fungal Insecticide, Chongqing 401331, China
- Key Laboratory of Gene Function and Regulation Technologies Under Chongqing Municipal Education Commission, Chongqing 401331, China
- Correspondence: (Y.X.); (K.J.); Tel.: +86-23-65120990 (Y.X.)
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Meng Q, Wu PP, Li MM, Shu RH, Zhou GL, Zhang JH, Zhang H, Jiang H, Qin QL, Zou Z. Distinct Responses of Thitarodes xiaojinensis β-1,3-Glucan Recognition Protein-1 and Immulectin-8 to Ophiocordyceps sinensis and Cordyceps militaris Infection. THE JOURNAL OF IMMUNOLOGY 2021; 207:200-209. [PMID: 34162722 DOI: 10.4049/jimmunol.2000447] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 04/23/2021] [Indexed: 11/19/2022]
Abstract
Melanization and encapsulation are prominent defense responses against microbes detected by pattern recognition receptors of their host insects. In the ghost moth Thitarodes xiaojinensis, an activated immune system can melanize and encapsulate the fungus Cordyceps militaris However, these responses were hardly detected in the host hemolymph postinfection of another fungus Ophiocordyceps sinensis The immune interaction between O. sinensis and the host remains largely unknown, which hinders the artificial cultivation of Chinese cordyceps. We found that T. xiaojinensis β-1,3-glucan recognition protein-1 (βGRP1) was needed for prophenoloxidase activation induced by C. militaris Failure of βGRP1 to recognize O. sinensis is a primary reason for the lack of melanization in the infected host. Lyticase or snailase treatment combined with binding and immunofluorescence detection showed the existence of a protective layer preventing the fungus from βGRP1 recognition. Coimmunoprecipitation and mass spectrometry analysis indicated that βGRP1 interacted with immulectin-8 (IML8) via binding to C. militaris IML8 promotes encapsulation. This study suggests the roles of T. xiaojinensis βGRP1 and IML8 in modulating immune responses against C. militaris Most importantly, the data indicate that O. sinensis may evade melanization by preventing βGRP1 recognition.
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Affiliation(s)
- Qian Meng
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Pei-Pei Wu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Miao-Miao Li
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Rui-Hao Shu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Gui-Ling Zhou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Ji-Hong Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Huan Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Haobo Jiang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK; and
| | - Qi-Lian Qin
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China;
| | - Zhen Zou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China; .,Chinese Academy of Sciences Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
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Mei L, Wang X, Yin Y, Tang G, Wang C. Conservative production of galactosaminogalactan in Metarhizium is responsible for appressorium mucilage production and topical infection of insect hosts. PLoS Pathog 2021; 17:e1009656. [PMID: 34125872 PMCID: PMC8224951 DOI: 10.1371/journal.ppat.1009656] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 06/24/2021] [Accepted: 05/20/2021] [Indexed: 02/07/2023] Open
Abstract
The exopolysaccharide galactosaminogalactan (GAG) has been well characterized in Aspergilli, especially the human pathogen Aspergillus fumigatus. It has been found that a five-gene cluster is responsible for GAG biosynthesis in Aspergilli to mediate fungal adherence, biofilm formation, immunosuppression or induction of host immune defences. Herein, we report the presence of the conserved GAG biosynthetic gene cluster in the insect pathogenic fungus Metarhizium robertsii to mediate either similar or unique biological functions. Deletion of the gene cluster disabled fungal ability to produce GAG on germ tubes, mycelia and appressoria. Relative to the wild type strain, null mutant was impaired in topical infection but not injection of insect hosts. We found that GAG production by Metarhizium is partially acetylated and could mediate fungal adherence to hydrophobic insect cuticles, biofilm formation, and penetration of insect cuticles. In particular, it was first confirmed that this exopolymer is responsible for the formation of appressorium mucilage, the essential extracellular matrix formed along with the infection structure differentiation to mediate cell attachment and expression of cuticle degrading enzymes. In contrast to its production during A. fumigatus invasive growth, GAG is not produced on the Metarhizium cells harvested from insect hemocoels; however, the polymer can glue germ tubes into aggregates to form mycelium pellets in liquid culture. The results of this study unravel the biosynthesis and unique function of GAG in a fungal system apart from the aspergilli species.
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Affiliation(s)
- Lijuan Mei
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Xuewen Wang
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Ying Yin
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Guirong Tang
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Chengshu Wang
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
- * E-mail:
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Ding JL, Hou J, Li XH, Feng MG, Ying SH. Transcription Activator Swi6 Interacts with Mbp1 in MluI Cell Cycle Box-Binding Complex and Regulates Hyphal Differentiation and Virulence in Beauveria bassiana. J Fungi (Basel) 2021; 7:jof7060411. [PMID: 34070348 PMCID: PMC8273693 DOI: 10.3390/jof7060411] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/20/2021] [Accepted: 05/24/2021] [Indexed: 11/18/2022] Open
Abstract
Mbp1 protein acts as a DNA-binding protein in MluI cell cycle box-binding complex (MBF) and plays an essential role in filamentous myco-pathogen Beauveria bassiana.In the current study, BbSwi6 (a homologue of yeast Swi6) was functionally characterized in B.bassiana. Both BbSwi6 and BbMbp1 localize in the nucleus and display a direct interaction relationship which is indicated by a yeast two-hybrid assay. BbSwi6 significantly contributes to hyphal growth, asexual sporulation and virulence. On the aerial surface, ΔBbSwi6 grew slower on various nutrients and displayed abnormal conidia-producing structures, which hardly produced conidia. In liquid media, BbSwi6 loss led to 90% reduction in blastospore yield. Finally, the virulence of the ΔBbSwi6 mutant was modestly weakened with a reduction of 20% in median lethal time. Comparative transcriptomics revealed that BbSwi6 mediated different transcriptomes during fungal development into conidia and blastospores. Notably, under the indicated condition, the BbSwi6-mediated transcriptome significantly differed to that mediated by BbMbp1. Our results demonstrate that, in addition to their roles as the interactive components in MBF, BbSwi6 and BbMbp1 mediate divergent genetic pathways during morphological transitions in B. bassiana.
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Identification of the Ricin-B-Lectin LdRBLk in the Colorado Potato Beetle and an Analysis of Its Expression in Response to Fungal Infections. J Fungi (Basel) 2021; 7:jof7050364. [PMID: 34066637 PMCID: PMC8148562 DOI: 10.3390/jof7050364] [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: 04/01/2021] [Revised: 04/26/2021] [Accepted: 05/04/2021] [Indexed: 01/15/2023] Open
Abstract
Ricin-B-lectins (RBLs) have been identified in many groups of organisms, including coleopterans insects, particularly the Colorado potato beetle Leptinotarsa decemlineata (LdRBLs). We hypothesized that one of these LdRBLs (LdRBLk) may be involved in the immune response to fungal infections. We performed a theoretical analysis of the structure of this protein. Additionally, the expression levels of the LdRBlk gene were measured in L. decemlineata in response to infections with the fungi Metarhizium robertsii and Beauveria bassiana. The expression levels of LdRBlk in the L. decemlineata cuticle and fat body were increased in response to both infections. The induction of LdRBlk expression was dependent on the susceptibility of larvae to the fungi. Upregulation of the LdRBlk gene was also observed in response to other stresses, particularly thermal burns. Elevation of LdRBlk expression was frequently observed to be correlated with the expression of the antimicrobial peptide attacin but was not correlated with hsp90 regulation. Commercially available β-lectin of ricin from Ricinuscommunis was observed to inhibit the germination of conidia of the fungi. We suggest that LdRBLk is involved in antifungal immune responses in the Colorado potato beetle, either exerting fungicidal properties directly or acting as a modulator of the immune response.
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45
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Mascarin GM, Iwanicki NS, Ramirez JL, Delalibera Í, Dunlap CA. Transcriptional Responses of Beauveria bassiana Blastospores Cultured Under Varying Glucose Concentrations. Front Cell Infect Microbiol 2021; 11:644372. [PMID: 33842391 PMCID: PMC8024584 DOI: 10.3389/fcimb.2021.644372] [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: 12/21/2020] [Accepted: 03/09/2021] [Indexed: 11/17/2022] Open
Abstract
Culturing the entomopathogenic fungus, Beauveria bassiana, under high glucose concentrations coupled with high aeration results in a fungal developmental shift from hyphal growth to mostly blastospores (yeast-like cells). The underlying molecular mechanisms involved in this shift remain elusive. A systematic transcriptome analysis of the differential gene expression was preformed to uncover the fungal transcriptomic response to osmotic and oxidative stresses associated with the resulting high blastospore yield. Differential gene expression was compared under moderate (10% w/v) and high (20% w/v) glucose concentrations daily for three days. The RNAseq-based transcriptomic results depicted a higher proportion of downregulated genes when the fungus was grown under 20% glucose than 10%. Additional experiments explored a broader glucose range (4, 8, 12, 16, 20% w/v) with phenotype assessment and qRT-PCR transcript abundance measurements of selected genes. Antioxidant, calcium transport, conidiation, and osmosensor-related genes were highly upregulated in higher glucose titers (16-20%) compared to growth in lower glucose (4-6%) concentrations. The class 1 hydrophobin gene (Hyd1) was highly expressed throughout the culturing. Hyd1 is known to be involved in spore coat rodlet layer assembly, and indicates that blastospores or another cell type containing hydrophobin 1 is expressed in the haemocoel during the infection process. Furthermore, we found implications of the HOG signaling pathway with upregulation of homologous genes Ssk2 and Hog1 for all fermentation time points under hyperosmotic medium (20% glucose). These findings expand our knowledge of the molecular mechanisms behind blastospore development and may help facilitate large-scale industrial production of B. bassiana blastospores for pest control applications.
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Affiliation(s)
- Gabriel Moura Mascarin
- Laboratory of Environmental Microbiology, Brazilian Agricultural Research Corporation, Embrapa Environment, Jaguariúna, Brazil
| | - Natasha Sant'Anna Iwanicki
- Department of Entomology and Acarology, "Luiz de Queiroz" College of Agriculture/University of São Paulo (ESALQ/USP), Piracicaba, Brazil
| | - Jose Luis Ramirez
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, United States Department of Agriculture, Agriculture Research Service, Peoria, IL, United States
| | - Ítalo Delalibera
- Department of Entomology and Acarology, "Luiz de Queiroz" College of Agriculture/University of São Paulo (ESALQ/USP), Piracicaba, Brazil
| | - Christopher A Dunlap
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, United States Department of Agriculture, Agriculture Research Service, Peoria, IL, United States
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46
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Wei Z, Ortiz-Urquiza A, Keyhani NO. Altered Expression of Chemosensory and Odorant Binding Proteins in Response to Fungal Infection in the Red Imported Fire Ant, Solenopsis invicta. Front Physiol 2021; 12:596571. [PMID: 33746766 PMCID: PMC7970113 DOI: 10.3389/fphys.2021.596571] [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: 08/19/2020] [Accepted: 02/08/2021] [Indexed: 01/21/2023] Open
Abstract
Social insects have evolved acute mechanisms for sensing and mitigating the spread of microbial pathogens within their communities that include complex behaviors such as grooming and sanitation. Chemical sensing involves detection and transport of olfactory and other chemicals that are mediated by at least two distinct classes of small molecular weight soluble proteins known as chemosensory- and odorant binding proteins (CSPs and OBPs, respectively) that exist as protein families in all insects. However, to date, a systematic examination of the expression of these genes involved in olfactory and other pathways to microbial infection has yet to be reported. The red imported fire ant, Solenopsis invicta, is one of the most successful invasive organisms on our planet. Here, we examined the temporal gene expression profiles of a suite of S. invicta CSPs (SiCSPs1-22) and OBPs (SiOBPs1-16) in response to infection by the broad host range fungal insect pathogen, Beauveria bassiana. Our data show that within 24 h post-infection, i.e., before the fungus has penetrated the host cuticle, the expression of SiCSPs and SiOBPs is altered (mainly increased compared to uninfected controls), followed by suppression of SiCSP and select SiOBP expression 48 h post-infection and mixed responses at 72 h post-infection. A smaller group of SiBOPs, however, appeared to respond to fungal infection, with expression of SiOBP15 consistently higher during fungal infection over the time course examined. These data indicate dynamic gene expression responses of CSPs and OBPs to fungal infection that provide clues to mechanisms that might mediate detection of microbial pathogens, triggering grooming, and nest sanitation.
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Affiliation(s)
- Zhang Wei
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, China.,Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, United States
| | - Almudena Ortiz-Urquiza
- Department of Biosciences, College of Science, Swansea University, Swansea, United Kingdom
| | - Nemat O Keyhani
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, United States
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47
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Wang L, Wang J, Zhang X, Yin Y, Li R, Lin Y, Deng C, Yang K, Liu X, Wang Z. Pathogenicity of Metarhizium rileyi against Spodoptera litura larvae: Appressorium differentiation, proliferation in hemolymph, immune interaction, and reemergence of mycelium. Fungal Genet Biol 2021; 150:103508. [PMID: 33675988 DOI: 10.1016/j.fgb.2020.103508] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 12/19/2020] [Accepted: 12/25/2020] [Indexed: 01/07/2023]
Abstract
The pathogenicity of Metarhizium rileyi is a multi-faceted process that depends on many factors. This study attempts to decipher those factors of M. rileyi by investigating its pathogenicity against Spodoptera litura (Lepidoptera: Noctuidae) larvae. Through morphogenesis analysis, we for the first time demonstrated the infection structure, appressorium, of M. rileyi that can generate a more than 4 MPa turgor pressure. The Mrpmk1 gene was found to be essential for appressorium differentiation and mycelium reemerging, ΔMrpmk1 mutant exhibited no pathogenicity towards S. litura by natural infection process. Delayed appressorium formation time, decreased appressorium formation rate and turgor pressure of ΔMrpbs2 mutant manifested itself in postponed death time and lower mortality against S. litura. Following invasion into the larval hemocoel, M. rileyi cells transformed into blastospores, which may be conducive to dispersal and propagation, moreover, the blastospore form M. rileyi may subverted phagocytic defenses. Then M. rileyi cells morphed into extended hyphal body to cope with elongated hemocytes that participated in encapsulation. In the end, M. rileyi mycelia reemerged from the larval cadaver evenly to form muscardine cadaver. Eventually, conidia were produced to complete the infection cycle. During the infection, M. rileyi triggered both cellular and humoral immunity of S. litura. Besides morphological changes, stage-specifically produced oxalic acid and F-actin arrangement may play roles in nutrient acquisition and mycelium reemerging, respectively.
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Affiliation(s)
- Li Wang
- School of Life Science, Chongqing University, China
| | - Jing Wang
- Chongqing Tobacco Monopoly Bureau, China
| | - Xiufen Zhang
- School of Life Science, Chongqing University, China
| | - Youping Yin
- School of Life Science, Chongqing University, China.
| | - Ren Li
- School of Life Science, Chongqing University, China
| | - Yunlong Lin
- School of Life Science, Chongqing University, China
| | - Chaoqun Deng
- School of Life Science, Chongqing University, China
| | - Kai Yang
- School of Life Science, Chongqing University, China
| | - Xiaoqin Liu
- Chongqing Chemical Industry Vocational College, China
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48
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Zhang LB, Qiu TT, Guan Y, Huang ZH, Ye XY. Analyses of transcriptomics and metabolomics reveal pathway of vacuolar Sur7 contributed to biocontrol potential of entomopathogenic Beauveria bassiana. J Invertebr Pathol 2021; 181:107564. [PMID: 33689762 DOI: 10.1016/j.jip.2021.107564] [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: 11/02/2020] [Revised: 02/23/2021] [Accepted: 02/26/2021] [Indexed: 01/21/2023]
Abstract
Beauveria bassiana is a critical entomopathogenic fungus for pest biocontrol, whose efficiency depends on fungal development and stress resistance. Unlike its revealed location in plasma membrane patches in other organisms, B. bassiana Sur7 specifically localized in vacuoles. This vacuolar Sur7 was previously demonstrated to affect stress tolerance, hyphal development and virulence. There, however, remain more mechanistic details to be explored. In this study, transcriptomics and metabolomics were applied to investigate the mechanism of vacuolar Sur7. Analyses of transcriptomics and metabolomics displayed many differentially expressed genes and abundant metabolites in response to Sur7 loss, respectively. Together with genes associated with vacuolar biofunction (including transportation and hydrolysis), the altered metabolites contributed to cell wall construction and stress resistance. Particularly, an N-acetylglucosamine-associated Brg1/Nrg1 pathway was enriched and partially affected by Sur7. Absence of Sur7 changed the expression level of Brg1/Nrg1 pathway-related transcript factors, which interfered with downstream phenotype of sporulation. In addition, Sur7 was involved in the accumulation of sphingoid bases, which may affect sphingolipid-related signaling pathway. Although experimental evidence is further required, our studies provide a preliminary framework for future exploring the regulatory mechanism of Sur7, and give a new version of metabolic agency connecting Sur7 and downstream signaling pathway.
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Affiliation(s)
- Long-Bin Zhang
- Fujian Key Laboratory of Marine Enzyme Engineering, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian 350116, China.
| | - Ting-Ting Qiu
- Fujian Key Laboratory of Marine Enzyme Engineering, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian 350116, China
| | - Yi Guan
- Fujian Key Laboratory of Marine Enzyme Engineering, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian 350116, China
| | - Zhi-Hong Huang
- Chemical Engineering Institution, Huaqiao University, Xiamen, Fujian 361021, China
| | - Xiu-Yun Ye
- Fujian Key Laboratory of Marine Enzyme Engineering, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian 350116, China
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49
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Li L, Zhong K, Wang JL, Liu XS. Mechanism of Metarhizium rileyi evading cellular immune responses in Helicoverpa armigera. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2021; 106:e21769. [PMID: 33590536 DOI: 10.1002/arch.21769] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/28/2020] [Accepted: 12/31/2020] [Indexed: 06/12/2023]
Abstract
Upon entry into the hemocoel of host insects, entomopathogenic fungi switch to yeast-like hyphal bodies that are not recognized by host hemocytes and replicate extensively in the hemolymph. The mechanism by which hyphal bodies evade host cellular immunity is not well understood. This study compares Metarhizium rileyi conidia and hyphal bodies with respect to elicitation of the immune response of Helicoverpa armigera and recognition by host pattern recognition receptors (PRRs). We found that the ability of host hemocytes to phagocytize and nodulate hyphal bodies was weaker than those responses against conidia, suggesting that hyphal bodies are more able to evade host cellular immunity. Additionally, we found that the binding affinity of H. armigera β-1,3-glucan recognition proteins was much lower for hyphal bodies than for conidia. We observed no agglutination response of H. armigera C-type lectin 3 (HaCTL3) against hyphal bodies, and HaCTL3 bound significantly less to hyphal bodies than to conidia, indicating that host PRRs have a lower affinity for hyphal bodies than for conidia. This study provides direct evidence that the mechanism whereby entomopathogenic fungi escape host cellular immunity involves the inability of host PRRs to sufficiently recognize hyphal bodies to elicit the cellular immune response.
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Affiliation(s)
- Li Li
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Ke Zhong
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Jia-Lin Wang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Xu-Sheng Liu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
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50
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Zhang R, Feng S, Xie X, Huang Z, Wan Q, Wang S, Zhang Z. Dysbacteriosis of the Intestinal Flora Is an Important Reason for the Death of Adult House Flies Caused by Beauveria bassiana. Front Immunol 2021; 11:589338. [PMID: 33574812 PMCID: PMC7871782 DOI: 10.3389/fimmu.2020.589338] [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: 07/30/2020] [Accepted: 12/07/2020] [Indexed: 11/13/2022] Open
Abstract
Beauveria bassiana is one of the most widespread insect pathogens and can be used in the biological control of agricultural, forestry and medical pests. The mechanisms by which B. bassiana leads to mortality in different host insects are also different. For house flies, B. bassiana has strong virulence, but its microecological mechanism is not clear. In this paper, the virulence of three strains of B. bassiana (TB, CB and BB) isolated from different hosts to house flies was studied. The results showed that the three strains of B. bassiana had strong pathogenicity to house fly adults. Specifically, TB was the strongest, CB was the second strongest, and BB was the weakest, with maximum lethal effects on house fly populations 5, 6, and 7 days after infection, respectively. Further study showed that the intestinal flora of house flies was disordered 3, 4, and 5 days after B. bassiana TB, CB and BB strain infection, respectively. Intestinal flora dysbacteriosis may be an important reason for the death of house flies caused by B. bassiana. After infection, the negative interaction ratio of bacteria in the house fly intestine decreased, and the stronger the virulence was, the lower the negative interaction ratio was. The time from B. bassiana infection to intestinal flora dysbacteriosis was not fixed. We named this period the “spring stage”. The stronger the virulence of the B. bassiana strain was, the shorter the “spring stage” was. Therefore, the “spring stage” can be used as a virulence marker for evaluating the pathogenicity of different B. bassiana strains.
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Affiliation(s)
- Ruiling Zhang
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China.,School of Basic Medical Science, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China
| | - Shuo Feng
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China.,School of Basic Medical Science, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China
| | - Xiaochen Xie
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China.,School of Basic Medical Science, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China
| | - Zhendong Huang
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China.,School of Basic Medical Science, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China
| | - Qing Wan
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China.,School of Basic Medical Science, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China
| | - Shumin Wang
- School of Basic Medical Science, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China
| | - Zhong Zhang
- Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China.,School of Basic Medical Science, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China
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