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Dai M, Du W, Lu L, Zhang S. Transcription factors SltA and CrzA reversely regulate calcium homeostasis under calcium-limited conditions. Appl Environ Microbiol 2023; 89:e0117023. [PMID: 37874299 PMCID: PMC10686095 DOI: 10.1128/aem.01170-23] [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: 07/11/2023] [Accepted: 09/11/2023] [Indexed: 10/25/2023] Open
Abstract
IMPORTANCE Calcium ions are ubiquitous intracellular signaling molecules for many signaling pathways regulating the fungal response to stress and antifungal drugs. The concentration of intracellular calcium is tightly regulated in its storage, release, and distribution. CrzA is the best-studied transcription factor that regulates this process under sufficient calcium or other external signals. However, CrzA was excluded from nuclei and then lost transcriptional activation under calcium-limited conditions. The regulators in the Ca2+ signaling pathway under calcium-limited conditions remain unclear. Here, we identified SltA as a key regulator in the Ca2+ signaling pathway under calcium-limited conditions, and the underlying mechanisms were further explored in Aspergillus fumigatus. These findings reveal a transcriptional control pathway that precisely regulates calcium homeostasis under calcium-limited conditions.
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Affiliation(s)
- Mengyao Dai
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, China
| | - Wenlong Du
- Department of Bioinformatics, School of Life Sciences, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Ling Lu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, China
| | - Shizhu Zhang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, China
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Cho O, Takada S, Odaka T, Futamura S, Kurakado S, Sugita T. Tacrolimus (FK506) Exhibits Fungicidal Effects against Candida parapsilosis Sensu Stricto via Inducing Apoptosis. J Fungi (Basel) 2023; 9:778. [PMID: 37504766 PMCID: PMC10381508 DOI: 10.3390/jof9070778] [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: 06/26/2023] [Revised: 07/18/2023] [Accepted: 07/19/2023] [Indexed: 07/29/2023] Open
Abstract
Tacrolimus (FK506), an immunosuppressant and calcineurin inhibitor, has fungicidal effects. However, its fungicidal effect is thought to be limited to basidiomycetes, such as Cryptococcus and Malassezia, and not to ascomycetes. FK506 had no fungicidal effect on Candida albicans, C. auris, C. glabrata, C. guilliermondii, C. kefyr, C. krusei, and C. tropicalis (>8 µg/mL); however, C. parapsilosis was susceptible to it at low concentrations of 0.125-0.5 µg/mL. C. metapsilosis and C. orthopsils, previously classified as C. parapsilosis, are molecularly and phylogenetically closely related to C. parapsilosis, but neither species was sensitive to FK506. FK506 increased the mitochondrial reactive oxygen species production and cytoplasmic and mitochondrial calcium concentration and activated metacaspases, nuclear condensation, and DNA fragmentation, suggesting that it induced mitochondria-mediated apoptosis in C. parapsilosis. Elucidating why FK506 exhibits fungicidal activity only against C. parapsilosis will provide new information for developing novel antifungal drugs.
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Affiliation(s)
- Otomi Cho
- Department of Microbiology, Meiji Pharmaceutical University, Noshio, Kiyose 204-8588, Japan
| | - Shintaro Takada
- Department of Microbiology, Meiji Pharmaceutical University, Noshio, Kiyose 204-8588, Japan
| | - Takahiro Odaka
- Department of Microbiology, Meiji Pharmaceutical University, Noshio, Kiyose 204-8588, Japan
| | - Satoshi Futamura
- Department of Microbiology, Meiji Pharmaceutical University, Noshio, Kiyose 204-8588, Japan
| | - Sanae Kurakado
- Department of Microbiology, Meiji Pharmaceutical University, Noshio, Kiyose 204-8588, Japan
| | - Takashi Sugita
- Department of Microbiology, Meiji Pharmaceutical University, Noshio, Kiyose 204-8588, Japan
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3
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de Andrade IB, Corrêa-Junior D, Alves V, Figueiredo-Carvalho MHG, Santos MV, Almeida MA, Valdez AF, Nimrichter L, Almeida-Paes R, Frases S. Cyclosporine Affects the Main Virulence Factors of Cryptococcus neoformans In Vitro. J Fungi (Basel) 2023; 9:jof9040487. [PMID: 37108941 PMCID: PMC10140927 DOI: 10.3390/jof9040487] [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: 04/06/2023] [Revised: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 04/29/2023] Open
Abstract
This study aimed to investigate the effects of cyclosporine on the morphology, cell wall structure, and secretion characteristics of Cryptococcus neoformans. The minimum inhibitory concentration (MIC) of cyclosporine was found to be 2 µM (2.4 µg/mL) for the H99 strain. Yeast cells treated with cyclosporine at half the MIC showed altered morphology, including irregular shapes and elongated projections, without an effect on cell metabolism. Cyclosporine treatment resulted in an 18-fold increase in chitin and an 8-fold increase in lipid bodies, demonstrating changes in the fungal cell wall structure. Cyclosporine also reduced cell body and polysaccharide capsule diameters, with a significant reduction in urease secretion in C. neoformans cultures. Additionally, the study showed that cyclosporine increased the viscosity of secreted polysaccharides and reduced the electronegativity and conductance of cells. The findings suggest that cyclosporine has significant effects on C. neoformans morphology, cell wall structure, and secretion, which could have implications for the development of new antifungal agents.
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Affiliation(s)
- Iara Bastos de Andrade
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Dario Corrêa-Junior
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Vinicius Alves
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | | | - Marcos Vinicius Santos
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro 21941-902, Brazil
| | - Marcos Abreu Almeida
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro 21941-902, Brazil
| | - Alessandro Fernandes Valdez
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Leonardo Nimrichter
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Rede Micologia RJ, FAPERJ, Rio de Janeiro 21941-902, Brazil
| | - Rodrigo Almeida-Paes
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro 21941-902, Brazil
- Rede Micologia RJ, FAPERJ, Rio de Janeiro 21941-902, Brazil
| | - Susana Frases
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Rede Micologia RJ, FAPERJ, Rio de Janeiro 21941-902, Brazil
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Wang F, Han R, Chen S. An Overlooked and Underrated Endemic Mycosis-Talaromycosis and the Pathogenic Fungus Talaromyces marneffei. Clin Microbiol Rev 2023; 36:e0005122. [PMID: 36648228 PMCID: PMC10035316 DOI: 10.1128/cmr.00051-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Talaromycosis is an invasive mycosis endemic in tropical and subtropical Asia and is caused by the pathogenic fungus Talaromyces marneffei. Approximately 17,300 cases of T. marneffei infection are diagnosed annually, and the reported mortality rate is extremely high (~1/3). Despite the devastating impact of talaromycosis on immunocompromised individuals, particularly HIV-positive persons, and the increase in reported occurrences in HIV-uninfected persons, diagnostic and therapeutic approaches for talaromycosis have received far too little attention worldwide. In 2021, scientists living in countries where talaromycosis is endemic raised a global demand for it to be recognized as a neglected tropical disease. Therefore, T. marneffei and the infectious disease induced by this fungus must be treated with concern. T. marneffei is a thermally dimorphic saprophytic fungus with a complicated mycological growth process that may produce various cell types in its life cycle, including conidia, hyphae, and yeast, all of which are associated with its pathogenicity. However, understanding of the pathogenic mechanism of T. marneffei has been limited until recently. To achieve a holistic view of T. marneffei and talaromycosis, the current knowledge about talaromycosis and research breakthroughs regarding T. marneffei growth biology are discussed in this review, along with the interaction of the fungus with environmental stimuli and the host immune response to fungal infection. Importantly, the future research directions required for understanding this serious infection and its causative pathogenic fungus are also emphasized to identify solutions that will alleviate the suffering of susceptible individuals worldwide.
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Affiliation(s)
- Fang Wang
- Intensive Care Unit, Biomedical Research Center, Shenzhen Institute of Translational Medicine, Health Science Center, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People’s Hospital, Shenzhen, China
| | - RunHua Han
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Shi Chen
- Intensive Care Unit, Biomedical Research Center, Shenzhen Institute of Translational Medicine, Health Science Center, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People’s Hospital, Shenzhen, China
- Department of Burn and Plastic Surgery, Biomedical Research Center, Shenzhen Institute of Translational Medicine, Health Science Center, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People’s Hospital, Shenzhen, China
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Cao Y, He K, Li Q, Chen X, Mo H, Li Z, Ji Q, Li G, Du G, Yang H. Transcriptome analysis of Armillaria gallica 012 m in response to auxin. J Basic Microbiol 2023; 63:17-25. [PMID: 36449692 DOI: 10.1002/jobm.202200463] [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: 07/27/2022] [Revised: 10/18/2022] [Accepted: 10/22/2022] [Indexed: 12/02/2022]
Abstract
Gastrodia elata is an achlorophyllous and fully mycoheterotrophic orchid which obtains carbon and other nutrients from Armillaria species in its life cycle. Many researchers suggested that plant hormones, as signing molecules, play a central role in the plant-fungi interaction. In the process of Armillaria gallica 012 m cultivation, both exogenous indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) distinctly stimulated the growth of mycelia in solid media. The differential expression genes (DEGs) of A. gallica 012 m with IAA versus blank control (BK) and IBA versus BK were investigated. The results showed that more than 80% of DEGs of the IAA group were coincident with the DEGs of the IBA group, and more than half of upregulated DEGs and most of the downregulated DEGs of the IAA group coincided with those DEGs of the IBA group. Above research implied that A. gallica 012 m could perceive IAA and IBA, and possess similar responses and signaling pathways to IAA and IBA. The overlapping differential genes of the IAA group and IBA group were analyzed by GO term, and the results showed that several DEGs identified were related to biological processes including positive regulation of the biological process and biological process. The downregulated NmrA-like and FKBP_C genes might be benefit to the growth of mycelia. Those results can explain that exiguous IAA and IBA improved the growth of A. gallica to some extent. We speculate that IAA and IBA are signaling molecules, and regulate the expression of growth-related genes of A. gallica 012 m by the same signaling pathway.
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Affiliation(s)
- Yapu Cao
- Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China
| | - Kaixiang He
- Department of Chemistry, School of Chemistry and Environment, Yunnan Minzu University, Kunming, China
| | - Qingqing Li
- Life Science College, Southwest Forestry University, Kunming, China.,Kunming Xianghao Technology Co. Ltd., Kunming, China
| | - Xin Chen
- Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China
| | - Haiying Mo
- Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China
| | - Zhihao Li
- Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China
| | - Qiaolin Ji
- Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China
| | - Ganpeng Li
- Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China
| | - Gang Du
- Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China
| | - Haiying Yang
- Department of Chemistry, School of Chemistry and Environment, Yunnan Minzu University, Kunming, China
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Song PP, Wang Y, Hou YP, Mao XW, Liu ZL, Wei M, Yu JP, Wang B, Qian YY, Yan L, Xu S, Jiang YQ, Zhou DQ, Yin M, Dou J. Crucial role of Ca 2+ /CN signalling pathway in the antifungal activity of disenecioyl-cis-khellactone against Botrytis cinerea. PEST MANAGEMENT SCIENCE 2022; 78:4649-4659. [PMID: 35866518 DOI: 10.1002/ps.7085] [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: 01/28/2022] [Revised: 06/21/2022] [Accepted: 07/22/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Botrytis cinerea causes grey mould and is one of the most destructive fungal pathogens affecting important fruit and vegetable crops. In preliminary studies, we found that disenecioyl-cis-khellactone (DK) had strong antifungal activity against several fungi species including B. cinerea [half maximal effective concentration (EC50 ) = 11.0 μg mL-1 ]. In this study, we aimed to further evaluate the antifungal activity of DK against B. cinerea and determine the role of calcium ion/calcineurin (Ca2+ /CN) signalling pathway on its antifungal effect. RESULTS DK was effective against B. cinerea in both in vitro and in vivo assays. Exogenous Ca2+ reduced the antifungal activity of DK. The combination of DK and cyclosporine A (CsA) did not exhibit an additive effect against B. cinerea. In contrast to CsA, DK reduced the intracellular Ca2+ concentration in B. cinerea. DK bound to calcineurin A (cnA) and up-regulated the expression of PMC1 and PMR1 genes. Moreover, DK sensitivity of △bccnA significantly decreased compared with that of Bc05.10 strain. CONCLUSION DK is a promising lead compound for developing fungicides against B. cinerea. The Ca2+ /CN signalling pathway plays a crucial role in the DK antifungal activity, and cnA is one of the targets of DK against B. cinerea. DK directly reacts with cnA, which up-regulates the transcription of Ca2+ /CN-dependent target genes PMC1 and PMR1, decreasing the intracellular Ca2+ concentration and disturbing the intracellular Ca2+ balance, leading to cell death. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Ping-Ping Song
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Yu Wang
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Yi-Ping Hou
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Xue-Wei Mao
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Zong-Liang Liu
- Yantai University, School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Centre of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai, China
| | - Min Wei
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Jin-Ping Yu
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Bi Wang
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Yi-Yun Qian
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Lu Yan
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Shu Xu
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Yan-Qin Jiang
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Dong-Qin Zhou
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Min Yin
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Jian Dou
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
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Wang J, Gong J, Wang Q, Tang T, Li W. VDAC1 negatively regulates melanogenesis through the Ca 2+-calcineurin-CRTC1-MITF pathway. Life Sci Alliance 2022; 5:5/10/e202101350. [PMID: 35649693 PMCID: PMC9160443 DOI: 10.26508/lsa.202101350] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 05/21/2022] [Accepted: 05/23/2022] [Indexed: 12/03/2022] Open
Abstract
This study revealed an important and novel role of mitochondrial VDAC1 in regulating melanogenesis in resting melanocytes through a Ca2+-regulated pathway that is independent of the alpha-MSH/UVB pathway. Melanocytes produce melanin for protecting DNA from ultraviolet exposure to maintain genomic stability. However, the precise regulation of melanogenesis is not fully understood. VDAC1, which is mainly localized in the outer mitochondrial membrane, functions as a gatekeeper for the entry or exit of Ca2+ between mitochondria and the cytosol and participates in multiple physiological processes. Here, we showed a novel role of VDAC1 in melanogenesis. Depletion of VDAC1 increased pigment content and up-regulated melanogenic genes, TYR, TYRP1, and TYRP2. Knockdown of VDAC1 increased free cytosolic Ca2+ in cultured melanocytes at the resting state, which activated calcineurin through the Ca2+-calmodulin-CaN pathway. The activated CaN dephosphorylated CRTC1 to facilitate its nuclear translocation and ultimately up-regulated the transcription of the master regulator of melanogenesis MITF. Consistently, depletion of Vdac1 in mice led to up-regulation of the transcription of MITF and thereafter its targeted melanogenic genes. These findings suggest that VDAC1 is an important negative regulator of melanogenesis, which expands our knowledge about pigment production and implies its potential role in melanoma.
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Affiliation(s)
- Jianli Wang
- Beijing Key Laboratory for Genetics of Birth Defects, Beijing Pediatric Research Institute; MOE Key Laboratory of Major Diseases in Children; Rare Disease Center, National Center for Children's Health; Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Juanjuan Gong
- Beijing Key Laboratory for Genetics of Birth Defects, Beijing Pediatric Research Institute; MOE Key Laboratory of Major Diseases in Children; Rare Disease Center, National Center for Children's Health; Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Qiaochu Wang
- Beijing Key Laboratory for Genetics of Birth Defects, Beijing Pediatric Research Institute; MOE Key Laboratory of Major Diseases in Children; Rare Disease Center, National Center for Children's Health; Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Tieshan Tang
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
| | - Wei Li
- Beijing Key Laboratory for Genetics of Birth Defects, Beijing Pediatric Research Institute; MOE Key Laboratory of Major Diseases in Children; Rare Disease Center, National Center for Children's Health; Beijing Children's Hospital, Capital Medical University, Beijing, China
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Valero C, Colabardini AC, de Castro PA, Silva LP, Ries LNA, Pardeshi L, Wang F, Rocha MC, Malavazi I, Silva RN, Martins C, Domingos P, Pereira-Silva C, Bromley MJ, Wong KH, Goldman GH. Aspergillus Fumigatus ZnfA, a Novel Zinc Finger Transcription Factor Involved in Calcium Metabolism and Caspofungin Tolerance. FRONTIERS IN FUNGAL BIOLOGY 2021; 2:689900. [PMID: 37744107 PMCID: PMC10512341 DOI: 10.3389/ffunb.2021.689900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 07/16/2021] [Indexed: 09/26/2023]
Abstract
Invasive pulmonary aspergillosis is a life-threatening fungal infection especially in the immunocompromised patients. The low diversity of available antifungal drugs coupled with the emergence of antifungal resistance has become a worldwide clinical concern. The echinocandin Caspofungin (CSP) is recommended as a second-line therapy but resistance and tolerance mechanisms have been reported. However, how the fungal cell articulates the response to CSP is not completely understood. This work provides a detailed characterization of ZnfA, a transcription factor (TF) identified in previous screening studies that is involved in the A. fumigatus responses to calcium and CSP. This TF plays an important role in the regulation of iron homeostasis and cell wall organization in response to high CSP concentrations as revealed by Chromatin Immunoprecipitation coupled to DNA sequencing (ChIP-seq) analysis. Furthermore, ZnfA acts collaboratively with the key TF CrzA in modulating the response to calcium as well as cell wall and osmotic stresses. This study therefore describes the existence of an additional, previously unknown TF that bridges calcium signaling and the CSP cellular response and further exposes the complex connections that exist among different pathways which govern stress sensing and signaling in A. fumigatus.
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Affiliation(s)
- Clara Valero
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Ana Cristina Colabardini
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Lilian Pereira Silva
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | | | - Lakhansing Pardeshi
- Faculty of Health Sciences, University of Macau, Macau, China
- Genomics and Bioinformatics Core, Faculty of Health Sciences, University of Macau, Macau, China
| | - Fang Wang
- Faculty of Health Sciences, University of Macau, Macau, China
- Genomics and Bioinformatics Core, Faculty of Health Sciences, University of Macau, Macau, China
| | - Marina Campos Rocha
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Paulo, Brazil
| | - Iran Malavazi
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Paulo, Brazil
| | | | - Celso Martins
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
| | - Patrícia Domingos
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
| | - Cristina Pereira-Silva
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
| | - Michael J. Bromley
- Manchester Fungal Infection Group, Core Technology Facility, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom
- Manchester Academic Health Science Centre, Lydia Becker Institute of Immunology and Inflammation, Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
| | - Koon Ho Wong
- Faculty of Health Sciences, University of Macau, Macau, China
- Faculty of Health Sciences, Institute of Translational Medicine, University of Macau, Macau, China
| | - Gustavo H. Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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Zhang C, Ren Y, Gu H, Gao L, Zhang Y, Lu L. Calcineurin-mediated intracellular organelle calcium homeostasis is required for the survival of fungal pathogens upon extracellular calcium stimuli. Virulence 2021; 12:1091-1110. [PMID: 33843471 PMCID: PMC8043181 DOI: 10.1080/21505594.2021.1909954] [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] [Indexed: 12/15/2022] Open
Abstract
In eukaryotes, calcium not only is an essential mineral nutrient but also serves as an intracellular second messenger that is necessary for many physiological processes. Previous studies showed that the protein phosphatase-calcineurin protects fungi from toxicity caused by the extracellular calcium; however, little is known about how calcineurin mediates the cellular physiology process for this function. In this study, by monitoring intracellular calcium, particularly by tracking vacuolar calcium dynamics in living cells through a novel procedure using modified aequorin, we found that calcineurin dysfunction systematically caused abnormal intracellular calcium homeostasis in cytosol, mitochondria, and vacuole, leading to drastic autophagy, global organelle fragmentation accompanied with the increased expression of cell death-related enzymes, and cell death upon extracellular calcium stimuli. Notably, all detectable defective phenotypes seen with calcineurin mutants can be significantly suppressed by alleviating a cytosolic calcium overload or increasing vacuolar calcium storage capacity, suggesting toxicity of exogenous calcium to calcineurin mutants is tightly associated with abnormal cytosolic calcium accumulation and vacuolar calcium storage capacity deficiency. Our findings provide insights into how the original recognized antifungal drug target-calcineurin regulates intracellular calcium homeostasis for cell survival and may have important implications for antifungal therapy and clinical drug administration.
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Affiliation(s)
- Chi Zhang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Yiran Ren
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Huiyu Gu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Lu Gao
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Yuanwei Zhang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Ling Lu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
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10
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Stempinski PR, Zielinski JM, Dbouk NH, Huey ES, McCormack EC, Rubin AM, Chandrasekaran S, Kozubowski L. Genetic contribution to high temperature tolerance in Cryptococcus neoformans. Genetics 2021; 217:1-15. [PMID: 33683363 PMCID: PMC8045695 DOI: 10.1093/genetics/iyaa009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 10/24/2020] [Indexed: 11/12/2022] Open
Abstract
The human fungal pathogen Cryptococcus neoformans relies on a complex signaling network for the adaptation and survival at the host temperature. Protein phosphatase calcineurin is central to proliferation at 37°C but its exact contributions remain ill-defined. To better define genetic contributions to the C. neoformans temperature tolerance, 4031 gene knockouts were screened for genes essential at 37°C and under conditions that keep calcineurin inactive. Identified 83 candidate strains, potentially sensitive to 37°C, were subsequently subject to technologically simple yet robust assay, in which cells are exposed to a temperature gradient. This has resulted in identification of 46 genes contributing to the maximum temperature at which C. neoformans can proliferate (Tmax). The 46 mutants, characterized by a range of Tmax on drug-free media, were further assessed for Tmax under conditions that inhibit calcineurin, which led to identification of several previously uncharacterized knockouts exhibiting synthetic interaction with the inhibition of calcineurin. A mutant that lacked septin Cdc11 was among those with the lowest Tmax and failed to proliferate in the absence of calcineurin activity. To further define connections with calcineurin and the role for septins in high temperature growth, the 46 mutants were tested for cell morphology at 37°C and growth in the presence of agents disrupting cell wall and cell membrane. Mutants sensitive to calcineurin inhibition were tested for synthetic lethal interaction with deletion of the septin-encoding CDC12 and the localization of the septin Cdc3-mCherry. The analysis described here pointed to previously uncharacterized genes that were missed in standard growth assays indicating that the temperature gradient assay is a valuable complementary tool for elucidating the genetic basis of temperature range at which microorganisms proliferate.
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Affiliation(s)
- Piotr R Stempinski
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
| | - Jessica M Zielinski
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
| | - Nadir H Dbouk
- Department of Biology, Furman University, Greenville, SC 29613, USA
| | - Elizabeth S Huey
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
| | - Ellen C McCormack
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
| | - Alexander M Rubin
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
| | | | - Lukasz Kozubowski
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
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11
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Cyclophilin BcCyp2 Regulates Infection-Related Development to Facilitate Virulence of the Gray Mold Fungus Botrytis cinerea. Int J Mol Sci 2021; 22:ijms22041694. [PMID: 33567582 PMCID: PMC7914984 DOI: 10.3390/ijms22041694] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/01/2021] [Accepted: 02/04/2021] [Indexed: 11/23/2022] Open
Abstract
Cyclophilin (Cyp) and Ca2+/calcineurin proteins are cellular components related to fungal morphogenesis and virulence; however, their roles in mediating the pathogenesis of Botrytis cinerea, the causative agent of gray mold on over 1000 plant species, remain largely unexplored. Here, we show that disruption of cyclophilin gene BcCYP2 did not impair the pathogen mycelial growth, osmotic and oxidative stress adaptation as well as cell wall integrity, but delayed conidial germination and germling development, altered conidial and sclerotial morphology, reduced infection cushion (IC) formation, sclerotial production and virulence. Exogenous cyclic adenosine monophosphate (cAMP) rescued the deficiency of IC formation of the ∆Bccyp2 mutants, and exogenous cyclosporine A (CsA), an inhibitor targeting cyclophilins, altered hyphal morphology and prevented host-cell penetration in the BcCYP2 harboring strains. Moreover, calcineurin-dependent (CND) genes are differentially expressed in strains losing BcCYP2 in the presence of CsA, suggesting that BcCyp2 functions in the upstream of cAMP- and Ca2+/calcineurin-dependent signaling pathways. Interestingly, during IC formation, expression of BcCYP2 is downregulated in a mutant losing BcJAR1, a gene encoding histone 3 lysine 4 (H3K4) demethylase that regulates fungal development and pathogenesis, in B. cinerea, implying that BcCyp2 functions under the control of BcJar1. Collectively, our findings provide new insights into cyclophilins mediating the pathogenesis of B. cinerea and potential targets for drug intervention for fungal diseases.
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12
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Mouhoumed AZ, Mou YN, Tong SM, Ying SH, Feng MG. Three proline rotamases involved in calcium homeostasis play differential roles in stress tolerance, virulence and calcineurin regulation of Beauveria bassiana. Cell Microbiol 2020; 22:e13239. [PMID: 32602171 DOI: 10.1111/cmi.13239] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 06/02/2020] [Accepted: 06/11/2020] [Indexed: 01/20/2023]
Abstract
FK506-sensitive proline rotamases (FPRs), also known as FK506-binding proteins (FKBPs), can mediate immunosuppressive drug resistance in budding yeast but their physiological roles in filamentous fungi remain opaque. Here, we report that three FPRs (cytosolic/nuclear 12.15-kD Fpr1, membrane-associated 14.78-kD Fpr2 and nuclear 50.43-kD Fpr3) are all equally essential for cellular Ca2+ homeostasis and contribute significantly to calcineurin activity at different levels in the insect-pathogenic fungus Beauveria bassiana although the deletion of fpr1 alone conferred resistance to FK506. Radial growth, conidiation, conidial viability and virulence were less compromised in the absence of fpr1 or fpr2 than in the absence of fpr3, which abolished almost all growth on scant media and reduced growth moderately on rich media. The Δfpr3 mutant was more sensitive to Na+ , K+ , Mn2+ , Ca2+ , Cu2+ , metal chelate, heat shock and UVB irradiation than was Δfpr2 while both mutants were equally sensitive to Zn2+ , Mg2+ , Fe2+ , H2 O2 and cell wall-perturbing agents. In contrast, the Δfpr1 mutant was less sensitive to fewer stress cues. Most of 32 examined genes involved in DNA damage repair, Na+ /K+ detoxification or osmotolerance and Ca2+ homeostasis were downregulated sharply in Δfpr2 and Δfpr3 but rarely so affected in Δfpr1, coinciding well with their phenotypic changes. These findings uncover important, but differential, roles of three FPRs in the fungal adaptation to insect host and environment and provide novel insight into their essential roles in calcium signalling pathway.
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Affiliation(s)
- Amina-Zahra Mouhoumed
- MOE Laboratory of Biosystems Homeostasis & Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ya-Ni Mou
- MOE Laboratory of Biosystems Homeostasis & Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Sen-Miao Tong
- College of Agricultural and Food Science, Zhejiang A&F University, Lin'an, Zhejiang, China
| | - Sheng-Hua Ying
- MOE Laboratory of Biosystems Homeostasis & Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ming-Guang Feng
- MOE Laboratory of Biosystems Homeostasis & Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
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13
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Ito Y, Miyazaki T, Tanaka Y, Suematsu T, Nakayama H, Morita A, Hirayama T, Tashiro M, Takazono T, Saijo T, Shimamura S, Yamamoto K, Imamura Y, Izumikawa K, Yanagihara K, Kohno S, Mukae H. Roles of Elm1 in antifungal susceptibility and virulence in Candida glabrata. Sci Rep 2020; 10:9789. [PMID: 32555245 PMCID: PMC7299981 DOI: 10.1038/s41598-020-66620-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 05/21/2020] [Indexed: 11/09/2022] Open
Abstract
Elm1 is a serine/threonine kinase involved in multiple cellular functions, including cytokinesis, morphogenesis, and drug resistance in Saccharomyces cerevisiae; however, its roles in pathogenic fungi have not been reported. In this study, we created ELM1-deletion, ELM1-reconstituted, ELM1-overexpression, and ELM1-kinase-dead strains in the clinically important fungal pathogen Candida glabrata and investigated the roles of Elm1 in cell morphology, stress response, and virulence. The elm1Δ strain showed elongated morphology and a thicker cell wall, with analyses of cell-wall components revealing that this strain exhibited significantly increased chitin content relative to that in the wild-type and ELM1-overexpression strains. Although the elm1Δ strain exhibited slower growth than the other two strains, as well as increased sensitivity to high temperature and cell-wall-damaging agents, it showed increased virulence in a Galleria mellonella-infection model. Moreover, loss of Elm1 resulted in increased adhesion to agar plates and epithelial cells, which represent important virulence factors in C. glabrata. Furthermore, RNA sequencing revealed that expression levels of 30 adhesion-like genes were elevated in the elm1Δ strain. Importantly, all these functions were mediated by the kinase activity of Elm1. To our knowledge, this is the first report describing the functional characterization of Elm1 in pathogenic fungi.
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Affiliation(s)
- Yuya Ito
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Taiga Miyazaki
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan.
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
| | - Yutaka Tanaka
- Department of Infection and Host Defense, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Takashi Suematsu
- Central Electron Microscope Laboratory, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Hironobu Nakayama
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, Suzuka, Japan
| | - Akihiro Morita
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, Suzuka, Japan
| | - Tatsuro Hirayama
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Masato Tashiro
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Takahiro Takazono
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Tomomi Saijo
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Shintaro Shimamura
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Kazuko Yamamoto
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Yoshifumi Imamura
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Koichi Izumikawa
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Katsunori Yanagihara
- Department of Laboratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Shigeru Kohno
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Hiroshi Mukae
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
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14
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Li YH, Liu TB. Zinc Finger Proteins in the Human Fungal Pathogen Cryptococcus neoformans. Int J Mol Sci 2020; 21:ijms21041361. [PMID: 32085473 PMCID: PMC7072944 DOI: 10.3390/ijms21041361] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 02/13/2020] [Accepted: 02/13/2020] [Indexed: 12/17/2022] Open
Abstract
Zinc is one of the essential trace elements in eukaryotes and it is a critical structural component of a large number of proteins. Zinc finger proteins (ZNFs) are zinc-finger domain-containing proteins stabilized by bound zinc ions and they form the most abundant proteins, serving extraordinarily diverse biological functions. In recent years, many ZNFs have been identified and characterized in the human fungal pathogen Cryptococcus neoformans, a fungal pathogen causing fatal meningitis mainly in immunocompromised individuals. It has been shown that ZNFs play important roles in the morphological development, differentiation, and virulence of C. neoformans. In this review, we, first, briefly introduce the ZNFs and their classification. Then, we explain the identification and classification of the ZNFs in C. neoformans. Next, we focus on the biological role of the ZNFs functionally characterized so far in the sexual reproduction, virulence factor production, ion homeostasis, pathogenesis, and stress resistance in C. neoformans. We also discuss the perspectives on future function studies of ZNFs in C. neoformans.
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Affiliation(s)
- Yuan-Hong Li
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Microsporidia Infection and Prevention, Southwest University, Chongqing 400715, China
| | - Tong-Bao Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
- Chongqing Key Laboratory of Microsporidia Infection and Prevention, Southwest University, Chongqing 400715, China
- Correspondence: ; Tel.: +86-23-6825-1088
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15
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Zheng YQ, Pan KS, Latgé JP, Andrianopoulos A, Luo H, Yan RF, Wei JY, Huang CY, Cao CW. Calcineurin A Is Essential in the Regulation of Asexual Development, Stress Responses and Pathogenesis in Talaromyces marneffei. Front Microbiol 2020; 10:3094. [PMID: 32038542 PMCID: PMC6985273 DOI: 10.3389/fmicb.2019.03094] [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: 07/06/2019] [Accepted: 12/20/2019] [Indexed: 11/27/2022] Open
Abstract
Talaromyces marneffei is a common cause of infection in immunocompromised patients in Southeast Asia and Southern China. The pathogenicity of T. marneffei depends on the ability of the fungus to survive the cytotoxic processes of the host immune system and grow inside host macrophages. These mechanisms that allow T. marneffei to survive macrophage-induced death are poorly understood. In this study, we examined the role of a calcineurin homolog (cnaA) from T. marneffei during growth, morphogenesis and infection. Deletion of the cnaA gene in T. marneffei resulted in a strain with significant defects in conidiation, germination, morphogenesis, cell wall integrity, and resistance to various stressors. The ΔcnaA mutant showed a lower minimal inhibitory concentration (MIC) against caspofungin (16 μg/ml to 2 μg/ml) and micafungin (from 32 μg/ml to 4 μg/ml) compared with the wild-type. These results suggest that targeting calcineurin in combination with echinocandin treatment may be effective for life-threatening systemic T. marneffei infection. Importantly, the cnaA mutant was incapable of adapting to the macrophage environment in vitro and displayed virulence defects in a mouse model of invasive talaromycosis. For the first time, a role has been shown for cnaA in the morphology and pathogenicity of a dimorphic pathogenic filamentous fungus.
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Affiliation(s)
- Yan-Qing Zheng
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Kai-Su Pan
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | | | - Alex Andrianopoulos
- School of Biosciences, The University of Melbourne, Parkville, VIC, Australia
| | - Hong Luo
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Ru-Fan Yan
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Jin-Ying Wei
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Chun-Yang Huang
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Cun-Wei Cao
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
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16
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Park HS, Lee SC, Cardenas ME, Heitman J. Calcium-Calmodulin-Calcineurin Signaling: A Globally Conserved Virulence Cascade in Eukaryotic Microbial Pathogens. Cell Host Microbe 2020; 26:453-462. [PMID: 31600499 DOI: 10.1016/j.chom.2019.08.004] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/29/2019] [Accepted: 08/02/2019] [Indexed: 12/19/2022]
Abstract
Calcium is an abundant intracellular ion, and calcium homeostasis plays crucial roles in several cellular processes. The calcineurin signaling cascade is one of the major pathways governed by intracellular calcium. Calcineurin, a conserved protein from yeast to humans, is a calcium-calmodulin-dependent serine-threonine-specific phosphatase that orchestrates cellular stress responses. In eukaryotic microbial pathogens, calcineurin controls essential virulence pathways, such as the ability to grow at host temperature, morphogenesis to enable invasive hyphal growth, drug tolerance and resistance, cell wall integrity, and sexual development. Therefore, the calcineurin cascade is an attractive target in drug development against eukaryotic pathogens. In the present review, we summarize and discuss the current knowledge on the roles of calcineurin in eukaryotic microbial pathogens, focusing on fungi and parasitic protists.
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Affiliation(s)
- Hee-Soo Park
- School of Food Science and Biotechnology, Institute of Agricultural Science and Technology, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Soo Chan Lee
- South Texas Center for Emerging Infectious Diseases (STCEID), Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Maria E Cardenas
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
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17
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Li Y, Ren H, Zhao Y, Sun J, Fan Y, Jin D, Pei Y. Characterization of three FK506-binding proteins in the entomopathogenic fungus Beauveria bassiana. J Invertebr Pathol 2020; 171:107334. [PMID: 32006551 DOI: 10.1016/j.jip.2020.107334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/26/2020] [Accepted: 01/28/2020] [Indexed: 10/25/2022]
Abstract
FK506 binding proteins (FKBPs) participate in regulation of diverse biological processes. However, the role of these proteins in insect-pathogenic fungi is far from well understood. To investigate the functions of FKBPs in Beauveria bassiana, a widely used entomopathogenic fungus for control of insect pests, we identify three putative FKBP genes, Bbfkbp12, Bbfkbp15, and Bbfkbp50, in the fungus. Gene-disruption experiments show that loss of Bbfkbp12 results in a significant increase of resistance of B. bassiana against the immunosuppressive compounds FK506 and rapamycin, while loss of Bbfkbp50 leads to the resistance to the ergosterol synthesis inhibitor lovastatin. Transcription assays of calcineurin (CaN)- and mTOR (mammalian target of rapamycin)-downstream target genes confirm that BbFKBP12 is the target of both FK506 and rapamycin, associated with CaN- and mTOR-signal pathways in B. bassiana. GFP-tagging of the proteins shows that BbFKBP12 and BbFKBP15 localize in cytoplasm while BbFKBP50 in nucleus. Our results provide useful information for the study of functions of CaN- and mTOR-mediated signaling, and ergosterol synthesis in the entomopathogenic fungi.
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Affiliation(s)
- Yujie Li
- Biotechnology Research Center, Southwest University, Beibei, Chongqing 400716, China
| | - Hui Ren
- Biotechnology Research Center, Southwest University, Beibei, Chongqing 400716, China
| | - Yutao Zhao
- Biotechnology Research Center, Southwest University, Beibei, Chongqing 400716, China
| | - Jiyuan Sun
- Biotechnology Research Center, Southwest University, Beibei, Chongqing 400716, China
| | - Yanhua Fan
- Biotechnology Research Center, Southwest University, Beibei, Chongqing 400716, China
| | - Dan Jin
- Biotechnology Research Center, Southwest University, Beibei, Chongqing 400716, China
| | - Yan Pei
- Biotechnology Research Center, Southwest University, Beibei, Chongqing 400716, China.
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18
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Abstract
Aspergilli produce conidia for reproduction or to survive hostile conditions, and they are highly effective in the distribution of conidia through the environment. In immunocompromised individuals, inhaled conidia can germinate inside the respiratory tract, which may result in invasive pulmonary aspergillosis. The management of invasive aspergillosis has become more complex, with new risk groups being identified and the emergence of antifungal resistance. Patient survival is threatened by these developments, stressing the need for alternative therapeutic strategies. As germination is crucial for infection, prevention of this process might be a feasible approach. A broader understanding of conidial germination is important to identify novel antigermination targets. In this review, we describe conidial resistance against various stresses, transition from dormant conidia to hyphal growth, the underlying molecular mechanisms involved in germination of the most common Aspergillus species, and promising antigermination targets. Germination of Aspergillus is characterized by three morphotypes: dormancy, isotropic growth, and polarized growth. Intra- and extracellular proteins play an important role in the protection against unfavorable environmental conditions. Isotropically expanding conidia remodel the cell wall, and biosynthetic machineries are needed for cellular growth. These biosynthetic machineries are also important during polarized growth, together with tip formation and the cell cycle machinery. Genes involved in isotropic and polarized growth could be effective antigermination targets. Transcriptomic and proteomic studies on specific Aspergillus morphotypes will improve our understanding of the germination process and allow discovery of novel antigermination targets and biomarkers for early diagnosis and therapy.
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19
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de Castro PA, Colabardini AC, Manfiolli AO, Chiaratto J, Silva LP, Mattos EC, Palmisano G, Almeida F, Persinoti GF, Ries LNA, Mellado L, Rocha MC, Bromley M, Silva RN, de Souza GS, Loures FV, Malavazi I, Brown NA, Goldman GH. Aspergillus fumigatus calcium-responsive transcription factors regulate cell wall architecture promoting stress tolerance, virulence and caspofungin resistance. PLoS Genet 2019; 15:e1008551. [PMID: 31887136 PMCID: PMC6948819 DOI: 10.1371/journal.pgen.1008551] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/08/2020] [Accepted: 12/02/2019] [Indexed: 11/28/2022] Open
Abstract
Aspergillus fumigatus causes invasive aspergillosis, the most common life-threatening fungal disease of immuno-compromised humans. The treatment of disseminated infections with antifungal drugs, including echinocandin cell wall biosynthesis inhibitors, is increasingly challenging due to the rise of drug-resistant pathogens. The fungal calcium responsive calcineurin-CrzA pathway influences cell morphology, cell wall composition, virulence, and echinocandin resistance. A screen of 395 A. fumigatus transcription factor mutants identified nine transcription factors important to calcium stress tolerance, including CrzA and ZipD. Here, comparative transcriptomics revealed CrzA and ZipD regulated the expression of shared and unique gene networks, suggesting they participate in both converged and distinct stress response mechanisms. CrzA and ZipD additively promoted calcium stress tolerance. However, ZipD also regulated cell wall organization, osmotic stress tolerance and echinocandin resistance. The absence of ZipD in A. fumigatus caused a significant virulence reduction in immunodeficient and immunocompetent mice. The ΔzipD mutant displayed altered cell wall organization and composition, while being more susceptible to macrophage killing and eliciting an increased pro-inflammatory cytokine response. A higher number of neutrophils, macrophages and activated macrophages were found in ΔzipD infected mice lungs. Collectively, this shows that ZipD-mediated regulation of the fungal cell wall contributes to the evasion of pro-inflammatory responses and tolerance of echinocandin antifungals, and in turn promoting virulence and complicating treatment options.
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Affiliation(s)
- Patrícia Alves de Castro
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Ana Cristina Colabardini
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Adriana Oliveira Manfiolli
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Jéssica Chiaratto
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Lilian Pereira Silva
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Eliciane Cevolani Mattos
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Giuseppe Palmisano
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Fausto Almeida
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Gabriela Felix Persinoti
- Laboratório Nacional de Biorrenováveis (LNBR), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, São Paulo, Brasil
| | - Laure Nicolas Annick Ries
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Laura Mellado
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Marina Campos Rocha
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - Michael Bromley
- Manchester Fungal Infection Group, Institute of Inflammation and Repair, University of Manchester, Manchester, United Kingdom
| | - Roberto Nascimento Silva
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Gabriel Scalini de Souza
- Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo, São José dos Campos, Brazil
| | - Flávio Vieira Loures
- Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo, São José dos Campos, Brazil
| | - Iran Malavazi
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - Neil Andrew Brown
- Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, United Kingdom
| | - Gustavo H Goldman
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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Tacrolimus, not triamcinolone acetonide, interacts synergistically with itraconazole, terbinafine, bifonazole, and amorolfine against clinical dermatophyte isolates. J Mycol Med 2018; 28:612-616. [DOI: 10.1016/j.mycmed.2018.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/23/2018] [Accepted: 09/06/2018] [Indexed: 11/23/2022]
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21
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Dissecting the Roles of the Calcineurin Pathway in Unisexual Reproduction, Stress Responses, and Virulence in Cryptococcus deneoformans. Genetics 2017; 208:639-653. [PMID: 29233811 DOI: 10.1534/genetics.117.300422] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 12/07/2017] [Indexed: 01/12/2023] Open
Abstract
The Ca2+/calmodulin-dependent protein phosphatase calcineurin orchestrates sexual reproduction, stress responses, and virulence via branched downstream pathways in the opportunistic human fungal pathogen Cryptococcus neoformans The calcineurin-binding protein Cbp1, the calcineurin temperature suppressor Cts1, the calcineurin-responsive zinc finger transcription factor Crz1, and the calcineurin targets Pbp1, Tif3, and Puf4, all function downstream of calcineurin to orchestrate distinct cellular processes. To elucidate how the calcineurin pathway regulatory network governs unisexual reproduction, stress responses, and virulence, we have analyzed the self-filamentous C. deneoformans strain, XL280α, and generated double mutants of these calcineurin downstream genes. We demonstrated that calcineurin governs unisexual reproduction at different sexual developmental stages, in which the initiation of the yeast-hyphal morphological transition is independent of Crz1, whereas the sporulation process is dependent on Crz1. Calcineurin-dependent unisexual reproduction is independent of the pheromone response pathway. Crz1 synergistically interacts with different calcineurin downstream targets in responding to ER, high-calcium, and cell wall stresses. We observed a widespread synergy suggesting that these proteins function in complex branched pathways downstream of calcineurin with some functional redundancy, which may allow efficient signaling network rewiring within the pathway for prompt adaptation to changing environments. Finally, we showed that deletion of PBP1 or TIF3 in the cna1∆ mutant background conferred a modest level of growth tolerance at 37°, but that the cna1∆ pbp1∆ and cna1∆ tif3∆ double mutants were both avirulent, suggesting that calcineurin may control virulence via mechanisms beyond thermotolerance.
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22
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Bandara HMHN, Matsubara VH, Samaranayake LP. Future therapies targeted towards eliminating Candida biofilms and associated infections. Expert Rev Anti Infect Ther 2016; 15:299-318. [PMID: 27927053 DOI: 10.1080/14787210.2017.1268530] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Candida species are common human commensals and cause either superficial or invasive opportunistic infections. The biofilm form of candida as opposed to its suspended, planktonic form, is predominantly associated with these infections. Alternative or adjunctive therapies are urgently needed to manage Candida infections as the currently available short arsenal of antifungal drugs has been compromised due to their systemic toxicity, cross-reactivity with other drugs, and above all, by the emergence of drug-resistant Candida species due to irrational drug use. Areas covered: Combination anti-Candida therapies, antifungal lock therapy, denture cleansers, and mouth rinses have all been proposed as alternatives for disrupting candidal biofilms on different substrates. Other suggested approaches for the management of candidiasis include the use of natural compounds, such as probiotics, plants extracts and oils, antifungal quorum sensing molecules, anti-Candida antibodies and vaccines, cytokine therapy, transfer of primed immune cells, photodynamic therapy, and nanoparticles. Expert commentary: The sparsity of currently available antifungals and the plethora of proposed anti-candidal therapies is a distinct indication of the urgent necessity to develop efficacious therapies for candidal infections. Alternative drug delivery approaches, such as probiotics, reviewed here is likely to be a reality in clinical settings in the not too distant future.
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Affiliation(s)
- H M H N Bandara
- a School of Dentistry , The University of Queensland , Herston , QLD , Australia
| | - V H Matsubara
- b School of Dentistry , University of São Paulo , São Paulo , SP , Brazil.,c Department of Microbiology, Institute of Biomedical Sciences , University of São Paulo , São Paulo , SP , Brazil
| | - L P Samaranayake
- a School of Dentistry , The University of Queensland , Herston , QLD , Australia.,d Faculty of Dentistry , University of Kuwait , Kuwait
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Hernández-Ortiz P, Espeso EA. Spatiotemporal dynamics of the calcineurin target CrzA. Cell Signal 2016; 29:168-180. [PMID: 27832964 DOI: 10.1016/j.cellsig.2016.11.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 09/26/2016] [Accepted: 11/05/2016] [Indexed: 01/23/2023]
Abstract
The response of Aspergilli to elevated concentrations of extracellular calcium and manganese, or environmental alkalinization is mediated by CrzA, a calcineurin-responsive transcription factor (TF). CrzA is the effector of a signaling pathway which includes the apical protein's calmodulin and calcineurin, and the protein kinases GskA and CkiA. Preferentially located in the cytoplasm, CrzA is the only element of the pathway modifying its localization under those stress conditions, being imported into nuclei. Remarkably, there is a direct relationship between the nature/intensity of the stimulus and the pace of nuclear import and time of nuclear permanence of CrzA. Alkalinity caused a transient nuclear accumulation of CrzA while high Ca2+ and Mn2+ concentrations generated a long-lasting accumulation. Furthermore, Ca2+ concentrations (below 5mM) that are non-toxic for a crzAΔ mutant promoted full signaling of CrzA. However, micromolar concentrations or a mutation disrupting the interaction of CrzA with the phosphatase complex calcineurin, permitted the visualization of a transient and polarized nuclear accumulation of the TF in a tip-to-base gradient. Overall, these results support a model in which nucleo-cytoplasmic dynamics and transcriptional activity of CrzA are driven by apical signals transmitted by calmodulin and calcineurin. This communication is essential to understand Ca+2-induced stress response in fungi.
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Affiliation(s)
- Patricia Hernández-Ortiz
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain
| | - Eduardo A Espeso
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain.
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Abstract
ABSTRACT
Invasive fungal infections are becoming an increasingly important cause of human mortality and morbidity, particularly for immunocompromised populations. The fungal pathogens
Candida albicans
,
Cryptococcus neoformans
, and
Aspergillus fumigatus
collectively contribute to over 1 million human deaths annually. Hence, the importance of safe and effective antifungal therapeutics for the practice of modern medicine has never been greater. Given that fungi are eukaryotes like their human host, the number of unique molecular targets that can be exploited for drug development remains limited. Only three classes of molecules are currently approved for the treatment of invasive mycoses. The efficacy of these agents is compromised by host toxicity, fungistatic activity, or the emergence of drug resistance in pathogen populations. Here we describe our current arsenal of antifungals and highlight current strategies that are being employed to improve the therapeutic safety and efficacy of these drugs. We discuss state-of-the-art approaches to discover novel chemical matter with antifungal activity and highlight some of the most promising new targets for antifungal drug development. We feature the benefits of combination therapy as a strategy to expand our current repertoire of antifungals and discuss the antifungal combinations that have shown the greatest potential for clinical development. Despite the paucity of new classes of antifungals that have come to market in recent years, it is clear that by leveraging innovative approaches to drug discovery and cultivating collaborations between academia and industry, there is great potential to bolster the antifungal armamentarium.
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25
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Martin-Yken H, François JM, Zerbib D. Knr4: a disordered hub protein at the heart of fungal cell wall signalling. Cell Microbiol 2016; 18:1217-27. [PMID: 27199081 DOI: 10.1111/cmi.12618] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/14/2016] [Accepted: 05/17/2016] [Indexed: 02/05/2023]
Abstract
The most highly connected proteins in protein-protein interactions networks are called hubs; they generally connect signalling pathways. In Saccharomyces cerevisiae, Knr4 constitutes a connecting node between the two main signal transmission pathways involved in cell wall maintenance upon stress: the cell wall integrity and the calcium-calcineurin pathway. Knr4 is required to enable the cells to resist many cell wall-affecting stresses, and KNR4 gene deletion is synthetic lethal with the simultaneous deletion of numerous other genes involved in morphogenesis and cell wall biogenesis. Knr4 has been shown to engage in multiple physical interactions, an ability conferred by the intrinsic structural adaptability of major disordered regions present in the N-terminal and C-terminal parts of the protein. Taking all together, Knr4 is an intrinsically disordered hub protein. Available data from other fungi indicate the conservation of Knr4 homologs cellular function and localization at sites of polarized growth among fungal species, including pathogenic species. Because of their particular role in morphogenesis control and of their fungal specificity, these proteins could constitute interesting new pharmaceutical drug targets for antifungal combination therapy.
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Affiliation(s)
- Hélène Martin-Yken
- LISBP, Université Fédérale de Toulouse, CNRS, INRA, INSA, 135 Avenue de Rangueil, F-31077, Toulouse, France
| | - Jean Marie François
- LISBP, Université Fédérale de Toulouse, CNRS, INRA, INSA, 135 Avenue de Rangueil, F-31077, Toulouse, France
| | - Didier Zerbib
- LISBP, Université Fédérale de Toulouse, CNRS, INRA, INSA, 135 Avenue de Rangueil, F-31077, Toulouse, France.,Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, F-31077, Toulouse, France
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Spitzer M, Robbins N, Wright GD. Combinatorial strategies for combating invasive fungal infections. Virulence 2016; 8:169-185. [PMID: 27268286 DOI: 10.1080/21505594.2016.1196300] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Invasive fungal infections are an important cause of human mortality and morbidity, particularly for immunocompromised populations. However, there remains a paucity of antifungal drug treatments available to combat these fungal pathogens. Further, antifungal compounds are plagued with problems such as host toxicity, fungistatic activity, and the emergence of drug resistance in pathogen populations. A promising therapeutic strategy to increase drug effectiveness and mitigate the emergence of drug resistance is through the use of combination drug therapy. In this review we describe the current arsenal of antifungals in medicine and elaborate on the benefits of combination therapy to expand our current antifungal drug repertoire. We examine those antifungal combinations that have shown potential against fungal pathogens and discuss strategies being employed to discover novel combination therapeutics, in particular combining antifungal agents with non-antifungal bioactive compounds. The findings summarized in this review highlight the promise of combinatorial strategies in combatting invasive mycoses.
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Affiliation(s)
- Michaela Spitzer
- a Michael G. DeGroote Institute for Infectious Disease Research and the Department of Biochemistry and Biomedical Sciences , McMaster University , Hamilton , ON , Canada
| | - Nicole Robbins
- a Michael G. DeGroote Institute for Infectious Disease Research and the Department of Biochemistry and Biomedical Sciences , McMaster University , Hamilton , ON , Canada
| | - Gerard D Wright
- a Michael G. DeGroote Institute for Infectious Disease Research and the Department of Biochemistry and Biomedical Sciences , McMaster University , Hamilton , ON , Canada
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27
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Calcineurin and Calcium Channel CchA Coordinate the Salt Stress Response by Regulating Cytoplasmic Ca2+ Homeostasis in Aspergillus nidulans. Appl Environ Microbiol 2016; 82:3420-3430. [PMID: 27037124 DOI: 10.1128/aem.00330-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 03/28/2016] [Indexed: 11/20/2022] Open
Abstract
The eukaryotic calcium/calmodulin-dependent protein phosphatase calcineurin is crucial for the environmental adaption of fungi. However, the mechanism of coordinate regulation of the response to salt stress by calcineurin and the high-affinity calcium channel CchA in fungi is not well understood. Here we show that the deletion of cchA suppresses the hyphal growth defects caused by the loss of calcineurin under salt stress in Aspergillus nidulans Additionally, the hypersensitivity of the ΔcnaA strain to extracellular calcium and cell-wall-damaging agents can be suppressed by cchA deletion. Using the calcium-sensitive photoprotein aequorin to monitor the cytoplasmic Ca(2+) concentration ([Ca(2+)]c) in living cells, we found that calcineurin negatively regulates CchA on calcium uptake in response to external calcium in normally cultured cells. However, in salt-stress-pretreated cells, loss of either cnaA or cchA significantly decreased the [Ca(2+)]c, but a deficiency in both cnaA and cchA switches the [Ca(2+)]c to the reference strain level, indicating that calcineurin and CchA synergistically coordinate calcium influx under salt stress. Moreover, real-time PCR results showed that the dysfunction of cchA in the ΔcnaA strain dramatically restored the expression of enaA (a major determinant for sodium detoxification), which was abolished in the ΔcnaA strain under salt stress. These results suggest that double deficiencies of cnaA and cchA could bypass the requirement of calcineurin to induce enaA expression under salt stress. Finally, YvcA, a member of the transient receptor potential channel (TRPC) protein family of vacuolar Ca(2+) channels, was proven to compensate for calcineurin-CchA in fungal salt stress adaption.IMPORTANCE The feedback inhibition relationship between calcineurin and the calcium channel Cch1/Mid1 has been well recognized from yeast. Interestingly, our previous study (S. Wang et al., PLoS One 7:e46564, 2012, http://dx.doi.org/10.1371/journal.pone.0046564) showed that the deletion of cchA could suppress the hyphal growth defects caused by the loss of calcineurin under salt stress in Aspergillus nidulans In this study, our findings suggest that fungi are able to develop a unique mechanism for adapting to environmental salt stress. Compared to cells cultured normally, the NaCl-pretreated cells had a remarkable increase in transient [Ca(2+)]c Furthermore, we show that calcineurin and CchA are required to modulate cellular calcium levels and synergistically coordinate calcium influx under salt stress. Finally, YvcA, a member of of the TRPC family of vacuolar Ca(2+) channels, was proven to compensate for calcineurin-CchA in fungal salt stress adaption. The findings in this study provide insights into the complex regulatory links between calcineurin and CchA to maintain cytoplasmic Ca(2+) homeostasis in response to different environments.
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Zhang Y, Zheng Q, Sun C, Song J, Gao L, Zhang S, Muñoz A, Read ND, Lu L. Palmitoylation of the Cysteine Residue in the DHHC Motif of a Palmitoyl Transferase Mediates Ca2+ Homeostasis in Aspergillus. PLoS Genet 2016; 12:e1005977. [PMID: 27058039 PMCID: PMC4825924 DOI: 10.1371/journal.pgen.1005977] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 03/15/2016] [Indexed: 01/08/2023] Open
Abstract
Finely tuned changes in cytosolic free calcium ([Ca2+]c) mediate numerous intracellular functions resulting in the activation or inactivation of a series of target proteins. Palmitoylation is a reversible post-translational modification involved in membrane protein trafficking between membranes and in their functional modulation. However, studies on the relationship between palmitoylation and calcium signaling have been limited. Here, we demonstrate that the yeast palmitoyl transferase ScAkr1p homolog, AkrA in Aspergillus nidulans, regulates [Ca2+]c homeostasis. Deletion of akrA showed marked defects in hyphal growth and conidiation under low calcium conditions which were similar to the effects of deleting components of the high-affinity calcium uptake system (HACS). The [Ca2+]c dynamics in living cells expressing the calcium reporter aequorin in different akrA mutant backgrounds were defective in their [Ca2+]c responses to high extracellular Ca2+ stress or drugs that cause ER or plasma membrane stress. All of these effects on the [Ca2+]c responses mediated by AkrA were closely associated with the cysteine residue of the AkrA DHHC motif, which is required for palmitoylation by AkrA. Using the acyl-biotin exchange chemistry assay combined with proteomic mass spectrometry, we identified protein substrates palmitoylated by AkrA including two new putative P-type ATPases (Pmc1 and Spf1 homologs), a putative proton V-type proton ATPase (Vma5 homolog) and three putative proteins in A. nidulans, the transcripts of which have previously been shown to be induced by extracellular calcium stress in a CrzA-dependent manner. Thus, our findings provide strong evidence that the AkrA protein regulates [Ca2+]c homeostasis by palmitoylating these protein candidates and give new insights the role of palmitoylation in the regulation of calcium-mediated responses to extracellular, ER or plasma membrane stress. Palmitoylation is a reversible post-translational modification catalyzed by palmitoyl acyltransferases (PATs) and proteins that undergo this modification are involved in numerous intracellular functions. Yeast Akr1p was the first characterized PAT whilst HIP14, an Akr1p homolog in human, is one of the most highly conserved of 23 human PATs that catalyze the addition of palmitate to the Huntington protein which is of major importance in Huntington’s disease. Calcium serves numerous signaling and structural functions in all eukaryotes. However, studies on the relationship between calcium signaling and palmitoylation are lacking. In this study, we demonstrate that the palmitoyl transferase Akr1 homolog in the filamentous fungus Aspergillus nidulans, similar to the high-affinity calcium uptake system (HACS), is required for normal growth and sporulation in the presence of low extracellular calcium. We find that AkrA dysfunction decreases the transient increase in cytosolic free calcium induced by a high extracellular calcium stress, tunicamycin (which induces endoplasmic reticulum stress) or the antifungal agent itraconazole (which induces plasma membrane stress). The influence of AkrA on all of these processes involves its DHHC motif, which is required for palmitoylation of various proteins associated with many processes including calcium signaling and membrane trafficking. Our findings provide evidence for a crucial link between calcium signaling and palmitoylation, suggesting a possible role in the mechanistic basis of human PAT-related diseases. These results also indicate that regulators of posttranslational modification may provide promising antifungal targets for new therapies.
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Affiliation(s)
- Yuanwei Zhang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology; College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Qingqing Zheng
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology; College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Congcong Sun
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology; College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Jinxing Song
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology; College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Lina Gao
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology; College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Shizhu Zhang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology; College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Alberto Muñoz
- Manchester Fungal Infection Group, Institute of Inflammation and Repair, University of Manchester, Manchester, United Kingdom
| | - Nick D. Read
- Manchester Fungal Infection Group, Institute of Inflammation and Repair, University of Manchester, Manchester, United Kingdom
| | - Ling Lu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology; College of Life Sciences, Nanjing Normal University, Nanjing, China
- * E-mail:
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29
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Schmoll M, Dattenböck C, Carreras-Villaseñor N, Mendoza-Mendoza A, Tisch D, Alemán MI, Baker SE, Brown C, Cervantes-Badillo MG, Cetz-Chel J, Cristobal-Mondragon GR, Delaye L, Esquivel-Naranjo EU, Frischmann A, Gallardo-Negrete JDJ, García-Esquivel M, Gomez-Rodriguez EY, Greenwood DR, Hernández-Oñate M, Kruszewska JS, Lawry R, Mora-Montes HM, Muñoz-Centeno T, Nieto-Jacobo MF, Nogueira Lopez G, Olmedo-Monfil V, Osorio-Concepcion M, Piłsyk S, Pomraning KR, Rodriguez-Iglesias A, Rosales-Saavedra MT, Sánchez-Arreguín JA, Seidl-Seiboth V, Stewart A, Uresti-Rivera EE, Wang CL, Wang TF, Zeilinger S, Casas-Flores S, Herrera-Estrella A. The Genomes of Three Uneven Siblings: Footprints of the Lifestyles of Three Trichoderma Species. Microbiol Mol Biol Rev 2016; 80:205-327. [PMID: 26864432 PMCID: PMC4771370 DOI: 10.1128/mmbr.00040-15] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The genus Trichoderma contains fungi with high relevance for humans, with applications in enzyme production for plant cell wall degradation and use in biocontrol. Here, we provide a broad, comprehensive overview of the genomic content of these species for "hot topic" research aspects, including CAZymes, transport, transcription factors, and development, along with a detailed analysis and annotation of less-studied topics, such as signal transduction, genome integrity, chromatin, photobiology, or lipid, sulfur, and nitrogen metabolism in T. reesei, T. atroviride, and T. virens, and we open up new perspectives to those topics discussed previously. In total, we covered more than 2,000 of the predicted 9,000 to 11,000 genes of each Trichoderma species discussed, which is >20% of the respective gene content. Additionally, we considered available transcriptome data for the annotated genes. Highlights of our analyses include overall carbohydrate cleavage preferences due to the different genomic contents and regulation of the respective genes. We found light regulation of many sulfur metabolic genes. Additionally, a new Golgi 1,2-mannosidase likely involved in N-linked glycosylation was detected, as were indications for the ability of Trichoderma spp. to generate hybrid galactose-containing N-linked glycans. The genomic inventory of effector proteins revealed numerous compounds unique to Trichoderma, and these warrant further investigation. We found interesting expansions in the Trichoderma genus in several signaling pathways, such as G-protein-coupled receptors, RAS GTPases, and casein kinases. A particularly interesting feature absolutely unique to T. atroviride is the duplication of the alternative sulfur amino acid synthesis pathway.
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Affiliation(s)
- Monika Schmoll
- Austrian Institute of Technology, Department Health and Environment, Bioresources Unit, Tulln, Austria
| | - Christoph Dattenböck
- Austrian Institute of Technology, Department Health and Environment, Bioresources Unit, Tulln, Austria
| | | | | | - Doris Tisch
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria
| | - Mario Ivan Alemán
- Cinvestav, Department of Genetic Engineering, Irapuato, Guanajuato, Mexico
| | - Scott E Baker
- Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Christopher Brown
- University of Otago, Department of Biochemistry and Genetics, Dunedin, New Zealand
| | | | - José Cetz-Chel
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
| | | | - Luis Delaye
- Cinvestav, Department of Genetic Engineering, Irapuato, Guanajuato, Mexico
| | | | - Alexa Frischmann
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria
| | | | - Monica García-Esquivel
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
| | | | - David R Greenwood
- The University of Auckland, School of Biological Sciences, Auckland, New Zealand
| | - Miguel Hernández-Oñate
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
| | - Joanna S Kruszewska
- Polish Academy of Sciences, Institute of Biochemistry and Biophysics, Laboratory of Fungal Glycobiology, Warsaw, Poland
| | - Robert Lawry
- Lincoln University, Bio-Protection Research Centre, Lincoln, Canterbury, New Zealand
| | | | | | | | | | | | | | - Sebastian Piłsyk
- Polish Academy of Sciences, Institute of Biochemistry and Biophysics, Laboratory of Fungal Glycobiology, Warsaw, Poland
| | - Kyle R Pomraning
- Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Aroa Rodriguez-Iglesias
- Austrian Institute of Technology, Department Health and Environment, Bioresources Unit, Tulln, Austria
| | | | | | - Verena Seidl-Seiboth
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria
| | | | | | - Chih-Li Wang
- National Chung-Hsing University, Department of Plant Pathology, Taichung, Taiwan
| | - Ting-Fang Wang
- Academia Sinica, Institute of Molecular Biology, Taipei, Taiwan
| | - Susanne Zeilinger
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria University of Innsbruck, Institute of Microbiology, Innsbruck, Austria
| | | | - Alfredo Herrera-Estrella
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
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Albataineh MT, Kadosh D. Regulatory roles of phosphorylation in model and pathogenic fungi. Med Mycol 2015; 54:333-52. [PMID: 26705834 PMCID: PMC4818690 DOI: 10.1093/mmy/myv098] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 11/01/2015] [Indexed: 12/25/2022] Open
Abstract
Over the past 20 years, considerable advances have been made toward our understanding
of how post-translational modifications affect a wide variety of biological
processes, including morphology and virulence, in medically important fungi.
Phosphorylation stands out as a key molecular switch and regulatory modification that
plays a critical role in controlling these processes. In this article, we first
provide a comprehensive and up-to-date overview of the regulatory roles that both
Ser/Thr and non-Ser/Thr kinases and phosphatases play in model and pathogenic fungi.
Next, we discuss the impact of current global approaches that are being used to
define the complete set of phosphorylation targets (phosphoproteome) in medically
important fungi. Finally, we provide new insights and perspectives into the potential
use of key regulatory kinases and phosphatases as targets for the development of
novel and more effective antifungal strategies.
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Affiliation(s)
- Mohammad T Albataineh
- Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
| | - David Kadosh
- Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
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Juvvadi PR, Steinbach WJ. Calcineurin Orchestrates Hyphal Growth, Septation, Drug Resistance and Pathogenesis of Aspergillus fumigatus: Where Do We Go from Here? Pathogens 2015; 4:883-93. [PMID: 26694470 PMCID: PMC4693169 DOI: 10.3390/pathogens4040883] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 12/07/2015] [Accepted: 12/11/2015] [Indexed: 12/27/2022] Open
Abstract
Studies on fungal pathogens belonging to the ascomycota phylum are critical given the ubiquity and frequency with which these fungi cause infections in humans. Among these species, Aspergillus fumigatus causes invasive aspergillosis, a leading cause of death in immunocompromised patients. Fundamental to A. fumigatus pathogenesis is hyphal growth. However, the precise mechanisms underlying hyphal growth and virulence are poorly understood. Over the past 10 years, our research towards the identification of molecular targets responsible for hyphal growth, drug resistance and virulence led to the elucidation of calcineurin as a key signaling molecule governing these processes. In this review, we summarize our salient findings on the significance of calcineurin for hyphal growth and septation in A. fumigatus and propose future perspectives on exploiting this pathway for designing new fungal-specific therapeutics.
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Affiliation(s)
- Praveen R Juvvadi
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Duke University Medical Center, Durham, NC 27710, USA.
| | - William J Steinbach
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Duke University Medical Center, Durham, NC 27710, USA.
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
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Zhang C, Meng X, Wei X, Lu L. Highly efficient CRISPR mutagenesis by microhomology-mediated end joining in Aspergillus fumigatus. Fungal Genet Biol 2015; 86:47-57. [PMID: 26701308 DOI: 10.1016/j.fgb.2015.12.007] [Citation(s) in RCA: 166] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Revised: 11/30/2015] [Accepted: 12/09/2015] [Indexed: 01/15/2023]
Abstract
Filamentous fungi have a dominant nonhomologous-end joining (NHEJ) DNA repair pathway, which results in the majority of transformed progenies having random heterologous insertion mutagenesis. Thus, lack of a versatile genome-editing tool prevents us from carrying out precise genome editing to explore the mechanism of pathogenesis. Moreover, clinical isolates that have a wild-type ku80 background without any selection nutrition marker especially suffer from low homologous integration efficiency. In this study, we have established a highly efficient CRISPR mutagenesis system to carry out precise and efficient in-frame integration with or without marker insertion with approximately 95-100% accuracy via very short (approximately 35-bp) homology arms in a process referred to as microhomology-mediated end joining (MMEJ). Based on this system, we have successfully achieved an efficient and precise integration of an exogenous GFP tag at the predicted site without marker insertion and edited a conidial melanin gene pksP and a catalytic subunit of calcineurin gene cnaA at multiple predicted sites with or without selection marker insertion. Moreover, we found that MMEJ-mediated CRISPR-Cas9 mutagenesis is independent of the ku80 pathway, indicating that this system can function as a powerful and versatile genome-editing tool in clinical Aspergillus isolates.
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Affiliation(s)
- Chi Zhang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Xiuhua Meng
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Xiaolei Wei
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Ling Lu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
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Kim A, Cunningham KW. A LAPF/phafin1-like protein regulates TORC1 and lysosomal membrane permeabilization in response to endoplasmic reticulum membrane stress. Mol Biol Cell 2015; 26:4631-45. [PMID: 26510498 PMCID: PMC4678020 DOI: 10.1091/mbc.e15-08-0581] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 10/19/2015] [Indexed: 01/13/2023] Open
Abstract
The controlled permeabilization of lysosomes and vacuoles may represent an ancient manner of programmed cell death. It is shown that TORC1 is required for lysosomal membrane permeabilization and death of yeast cells that have been exposed to antifungals, and that a novel FYVE-domain protein regulates TORC1 signaling in these conditions. Lysosomal membrane permeabilization (LMP) is a poorly understood regulator of programmed cell death that involves leakage of luminal lysosomal or vacuolar hydrolases into the cytoplasm. In Saccharomyces cerevisiae, LMP can be induced by antifungals and endoplasmic reticulum stressors when calcineurin also has been inactivated. A genome-wide screen revealed Pib2, a relative of LAPF/phafin1 that regulates LMP in mammals, as a pro-LMP protein in yeast. Pib2 associated with vacuolar and endosomal limiting membranes in unstressed cells in a manner that depended on its FYVE domain and on phosphatidylinositol 3-phosphate (PI(3)P) biosynthesis. Genetic experiments suggest that Pib2 stimulates the activity of TORC1, a vacuole-associated protein kinase that is sensitive to rapamycin, in a pathway parallel to the Ragulator/EGO complex containing the GTPases Gtr1 and Gtr2. A hyperactivating mutation in the catalytic subunit of TORC1 restored LMP to the gtr1∆ and pib2∆ mutants and also prevented the synthetic lethality of the double mutants. These findings show novel roles of PI(3)P and Pib2 in the regulation of TORC1, which in turn promoted LMP and nonapoptotic death of stressed cells. Rapamycin prevented the death of the pathogenic yeast Candida albicans during exposure to fluconazole plus a calcineurin inhibitor, suggesting that TORC1 broadly promotes sensitivity to fungistats in yeasts.
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Affiliation(s)
- Adam Kim
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218
| | - Kyle W Cunningham
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218
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Falloon K, Juvvadi PR, Richards AD, Vargas-Muñiz JM, Renshaw H, Steinbach WJ. Characterization of the FKBP12-Encoding Genes in Aspergillus fumigatus. PLoS One 2015; 10:e0137869. [PMID: 26366742 PMCID: PMC4569257 DOI: 10.1371/journal.pone.0137869] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 08/22/2015] [Indexed: 01/11/2023] Open
Abstract
Invasive aspergillosis, largely caused by Aspergillus fumigatus, is responsible for a growing number of deaths among immunosuppressed patients. Immunosuppressants such as FK506 (tacrolimus) that target calcineurin have shown promise for antifungal drug development. FK506-binding proteins (FKBPs) form a complex with calcineurin in the presence of FK506 (FKBP12-FK506) and inhibit calcineurin activity. Research on FKBPs in fungi is limited, and none of the FKBPs have been previously characterized in A. fumigatus. We identified four orthologous genes of FKBP12, the human FK506 binding partner, in A. fumigatus and designated them fkbp12-1, fkbp12-2, fkbp12-3, and fkbp12-4. Deletional analysis of the four genes revealed that the Δfkbp12-1 strain was resistant to FK506, indicating FKBP12-1 as the key mediator of FK506-binding to calcineurin. The endogenously expressed FKBP12-1-EGFP fusion protein localized to the cytoplasm and nuclei under normal growth conditions but also to the hyphal septa following FK506 treatment, revealing its interaction with calcineurin. The FKBP12-1-EGFP fusion protein didn’t localize at the septa in the presence of FK506 in the cnaA deletion background, confirming its interaction with calcineurin. Testing of all deletion strains in the Galleria mellonella model of aspergillosis suggested that these proteins don’t play an important role in virulence. While the Δfkbp12-2 and Δfkbp12-3 strains didn’t show any discernable phenotype, the Δfkbp12-4 strain displayed slight growth defect under normal growth conditions and inhibition of the caspofungin-mediated “paradoxical growth effect” at higher concentrations of the antifungal caspofungin. Together, these results indicate that while only FKBP12-1 is the bona fide binding partner of FK506, leading to the inhibition of calcineurin in A. fumigatus, FKBP12-4 may play a role in basal growth and the caspofungin-mediated paradoxical growth response. Exploitation of differences between A. fumigatus FKBP12-1 and human FKBP12 will be critical for the generation of fungal-specific FK506 analogs to inhibit fungal calcineurin and treat invasive fungal disease.
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Affiliation(s)
- Katie Falloon
- Duke University School of Medicine, Durham, NC, United States of America
| | - Praveen R. Juvvadi
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Duke University Medical Center, Durham, NC, United States of America
| | - Amber D. Richards
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Duke University Medical Center, Durham, NC, United States of America
| | - José M. Vargas-Muñiz
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, United States of America
| | - Hilary Renshaw
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, United States of America
| | - William J. Steinbach
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Duke University Medical Center, Durham, NC, United States of America
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, United States of America
- * E-mail:
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Li F, Wang ZL, Zhang LB, Ying SH, Feng MG. The role of three calcineurin subunits and a related transcription factor (Crz1) in conidiation, multistress tolerance and virulence in Beauveria bassiana. Appl Microbiol Biotechnol 2014; 99:827-40. [DOI: 10.1007/s00253-014-6124-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 09/28/2014] [Accepted: 09/30/2014] [Indexed: 11/25/2022]
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de Castro PA, Chen C, de Almeida RSC, Freitas FZ, Bertolini MC, Morais ER, Brown NA, Ramalho LNZ, Hagiwara D, Mitchell TK, Goldman GH. ChIP-seq reveals a role for CrzA in the Aspergillus fumigatus high-osmolarity glycerol response (HOG) signalling pathway. Mol Microbiol 2014; 94:655-74. [PMID: 25196896 DOI: 10.1111/mmi.12785] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/03/2014] [Indexed: 12/28/2022]
Abstract
Aspergillus fumigatus is an opportunistic pathogen and allergen of mammals. Calcium signalling is essential for A. fumigatus pathogenicity and is regulated by the CrzA transcription factor. We used ChIP-seq (Chromatin Immunoprecipitation DNA sequencing) to explore CrzA gene targets in A. fumigatus. In total, 165 potential binding peaks including 102 directly regulated genes were identified, resulting in the prediction of the A[GT][CG]CA[AC][AG] CrzA-binding motif. The 102 CrzA putatively regulated genes exhibited a diverse array of functions. The phkB (Afu3g12530) histidine kinase and the sskB (Afu1g10940) MAP kinase kinase kinase of the HOG (high-osmolarity glycerol response) pathway were regulated by CrzA. Several members of the two-component system (TCS) and the HOG pathway were more sensitive to calcium. CrzA::GFP was translocated to the nucleus upon osmotic stress. CrzA is important for the phosphorylation of the SakA MAPK in response to osmotic shock. The ΔsskB was more sensitive to CaCl2 , NaCl, and paraquat stress, while being avirulent in a murine model of invasive pulmonary aspergillosis. The presence of CaCl2 and osmotic stresses resulted in synergistic inhibition of ΔcrzA and ΔsskB growth. These results suggest there is a genetic interaction between the A. fumigatus calcineurin-CrzA and HOG pathway that is essential for full virulence.
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Affiliation(s)
- Patrícia A de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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Colabardini AC, Ries LNA, Brown NA, Savoldi M, Dinamarco TM, von Zeska MR, Goldman MHS, Goldman GH. Protein kinase C overexpression suppresses calcineurin-associated defects in Aspergillus nidulans and is involved in mitochondrial function. PLoS One 2014; 9:e104792. [PMID: 25153325 PMCID: PMC4143261 DOI: 10.1371/journal.pone.0104792] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Accepted: 07/11/2014] [Indexed: 12/22/2022] Open
Abstract
In filamentous fungi, intracellular signaling pathways which are mediated by changing calcium levels and/or by activated protein kinase C (Pkc), control fungal adaptation to external stimuli. A rise in intracellular Ca2+ levels activates calcineurin subunit A (CnaA), which regulates cellular calcium homeostasis among other processes. Pkc is primarily involved in maintaining cell wall integrity (CWI) in response to different environmental stresses. Cross-talk between the Ca2+ and Pkc-mediated pathways has mainly been described in Saccharomyces cerevisiae and in a few other filamentous fungi. The presented study describes a genetic interaction between CnaA and PkcA in the filamentous fungus Aspergillus nidulans. Overexpression of pkcA partially rescues the phenotypes caused by a cnaA deletion. Furthermore, CnaA appears to affect the regulation of a mitogen-activated kinase, MpkA, involved in the CWI pathway. Reversely, PkcA is involved in controlling intracellular calcium homeostasis, as was confirmed by microarray analysis. Furthermore, overexpression of pkcA in a cnaA deletion background restores mitochondrial number and function. In conclusion, PkcA and CnaA-mediated signaling appear to share common targets, one of which appears to be MpkA of the CWI pathway. Both pathways also regulate components involved in mitochondrial biogenesis and function. This study describes targets for PkcA and CnaA-signaling pathways in an A. nidulans and identifies a novel interaction of both pathways in the regulation of cellular respiration.
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Affiliation(s)
- Ana Cristina Colabardini
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | | | - Neil Andrew Brown
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Marcela Savoldi
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Taísa Magnani Dinamarco
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Marcia Regina von Zeska
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Maria Helena S. Goldman
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Gustavo Henrique Goldman
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol – CTBE, Campinas, São Paulo, Brazil
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
- * E-mail:
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Juvvadi PR, Lamoth F, Steinbach WJ. Calcineurin-mediated regulation of hyphal growth, septation, and virulence in Aspergillus fumigatus. Mycopathologia 2014; 178:341-8. [PMID: 25118871 DOI: 10.1007/s11046-014-9794-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 07/31/2014] [Indexed: 01/26/2023]
Abstract
Calcineurin is a heterodimeric protein phosphatase complex composed of catalytic (CnaA) and regulatory (CnaB) subunits and plays diverse roles in regulating fungal stress responses, morphogenesis, and pathogenesis. Fungal pathogens utilize the calcineurin pathway to survive in the host environment and cause life-threatening infections. The immunosuppressive calcineurin inhibitors (FK506 and cyclosporine A) are active against fungi, making calcineurin a promising antifungal drug target. Here, we review novel findings on calcineurin localization and functions in Aspergillus fumigatus hyphal growth and septum formation through regulation of proteins involved in cell wall biosynthesis. Extensive mutational analysis in the functional domains of A. fumigatus CnaA has led to an understanding of the relevance of these domains for the localization and function of CnaA at the hyphal septum. An evolutionarily conserved novel mode of calcineurin regulation by phosphorylation in filamentous fungi was found to be responsible for virulence in A. fumigatus. This finding of a filamentous fungal-specific mechanism controlling hyphal growth and virulence represents a potential target for antifungal therapy.
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Affiliation(s)
- Praveen R Juvvadi
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center, 427 Jones Building, Research Drive, Durham, NC, 27710, USA,
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de Castro PA, Chiaratto J, Winkelströter LK, Bom VLP, Ramalho LNZ, Goldman MHS, Brown NA, Goldman GH. The involvement of the Mid1/Cch1/Yvc1 calcium channels in Aspergillus fumigatus virulence. PLoS One 2014; 9:e103957. [PMID: 25083783 PMCID: PMC4118995 DOI: 10.1371/journal.pone.0103957] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 07/03/2014] [Indexed: 11/30/2022] Open
Abstract
Aspergillus fumigatus is a major opportunistic pathogen and allergen of mammals. Calcium homeostasis and signaling is essential for numerous biological processes and also influences A. fumigatus pathogenicity. The presented study characterized the function of the A. fumigatus homologues of three Saccharomyces cerevisiae calcium channels, voltage-gated Cch1, stretch-activated Mid1 and vacuolar Yvc1. The A. fumigatus calcium channels cchA, midA and yvcA were regulated at transcriptional level by increased calcium levels. The YvcA::GFP fusion protein localized to the vacuoles. Both ΔcchA and ΔmidA mutant strains showed reduced radial growth rate in nutrient-poor minimal media. Interestingly, this growth defect in the ΔcchA strain was rescued by the exogenous addition of CaCl2. The ΔcchA, ΔmidA, and ΔcchA ΔmidA strains were also sensitive to the oxidative stress inducer, paraquat. Restriction of external Ca2+ through the addition of the Ca2+-chelator EGTA impacted upon the growth of the ΔcchA and ΔmidA strains. All the A. fumigatus ΔcchA, ΔmidA, and ΔyvcA strains demonstrated attenuated virulence in a neutropenic murine model of invasive pulmonary aspergillosis. Infection with the parental strain resulted in a 100% mortality rate at 15 days post-infection, while the mortality rate of the ΔcchA, ΔmidA, and ΔyvcA strains after 15 days post-infection was only 25%. Collectively, this investigation strongly indicates that CchA, MidA, and YvcA play a role in A. fumigatus calcium homeostasis and virulence.
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Affiliation(s)
- Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Jéssica Chiaratto
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Lizziane K. Winkelströter
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Vinícius Leite Pedro Bom
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | | | - Maria Helena S. Goldman
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Neil Andrew Brown
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Gustavo H. Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
- National Laboratory of Science and Technology of Bioethanol (CTBE), Campinas, Brazil
- * E-mail:
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Tsai HC, Chung KR. Calcineurin phosphatase and phospholipase C are required for developmental and pathological functions in the citrus fungal pathogen Alternaria alternata. MICROBIOLOGY-SGM 2014; 160:1453-1465. [PMID: 24763426 DOI: 10.1099/mic.0.077818-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Excessive Ca(2+) or compounds interfering with phosphoinositide cycling have been found to inhibit the growth of the tangerine pathotype of Alternaria alternata, suggesting a crucial role of Ca(2+) homeostasis in this pathotype. The roles of PLC1, a phospholipase C-coding gene and CAL1, a calcineurin phosphatase-coding gene were investigated. Targeted gene disruption showed that both PLC1 and CAL1 were required for vegetative growth, conidial formation and pathogenesis in citrus. Fungal strains lacking PLC1 or CAL1 exhibited extremely slow growth and induced small lesions on calamondin leaves. Δplc1 mutants produced fewer conidia, which germinated at slower rates than wild-type. Δcal1 mutants produced abnormal hyphae and failed to produce any mature conidia, but instead produced highly melanized bulbous hyphae with distinct septae. Fluorescence microscopy using Fluo-3 dye as a Ca(2+) indicator revealed that the Δplc1 mutant hyphae emitted stronger cytosolic fluorescence, and the Δcal1 mutant hyphae emitted less cytosolic fluorescence, than those of wild-type. Infection assessed on detached calamondin leaves revealed that application of CaCl2 or neomycin 24 h prior to inoculation provided protection against Alt. alternata. These data indicate that a dynamic equilibrium of cellular Ca(2+) is critical for developmental and pathological processes of Alt. alternata.
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Affiliation(s)
- Hsieh-Chin Tsai
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences (IFAS), University of Florida, 700 Experiment Station Road, Lake Alfred, FL 33850, USA
| | - Kuang-Ren Chung
- Department of Plant Pathology, IFAS, University of Florida, Gainesville, FL 32611, USA.,Citrus Research and Education Center, Institute of Food and Agricultural Sciences (IFAS), University of Florida, 700 Experiment Station Road, Lake Alfred, FL 33850, USA
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Schaenman JM, Khuu T, Kubak BM. Fungi as Eukaryotes: Understanding the Antifungal Effects of Immunosuppressive Drugs. CURRENT FUNGAL INFECTION REPORTS 2014. [DOI: 10.1007/s12281-013-0169-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Stress signaling pathways for the pathogenicity of Cryptococcus. EUKARYOTIC CELL 2013; 12:1564-77. [PMID: 24078305 DOI: 10.1128/ec.00218-13] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Sensing, responding, and adapting to the surrounding environment are crucial for all living organisms to survive, proliferate, and differentiate in their biological niches. This ability is also essential for Cryptococcus neoformans and its sibling species Cryptococcus gattii, as these pathogens have saprobic and parasitic life cycles in natural and animal host environments. The ability of Cryptococcus to cause fatal meningoencephalitis is highly related to its capability to remodel and optimize its metabolic and physiological status according to external cues. These cues act through multiple stress signaling pathways through a panoply of signaling components, including receptors/sensors, small GTPases, secondary messengers, kinases, transcription factors, and other miscellaneous adaptors or regulators. In this minireview, we summarize and highlight the importance of several stress signaling pathways that influence the pathogenicity of Cryptococcus and discuss future challenges in these areas.
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Juvvadi PR, Gehrke C, Fortwendel JR, Lamoth F, Soderblom EJ, Cook EC, Hast MA, Asfaw YG, Moseley MA, Creamer TP, Steinbach WJ. Phosphorylation of Calcineurin at a novel serine-proline rich region orchestrates hyphal growth and virulence in Aspergillus fumigatus. PLoS Pathog 2013; 9:e1003564. [PMID: 23990785 PMCID: PMC3749960 DOI: 10.1371/journal.ppat.1003564] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 07/02/2013] [Indexed: 12/26/2022] Open
Abstract
The fungus Aspergillus fumigatus is a leading infectious killer in immunocompromised patients. Calcineurin, a calmodulin (CaM)-dependent protein phosphatase comprised of calcineurin A (CnaA) and calcineurin B (CnaB) subunits, localizes at the hyphal tips and septa to direct A. fumigatus invasion and virulence. Here we identified a novel serine-proline rich region (SPRR) located between two conserved CnaA domains, the CnaB-binding helix and the CaM-binding domain, that is evolutionarily conserved and unique to filamentous fungi and also completely absent in human calcineurin. Phosphopeptide enrichment and tandem mass spectrometry revealed the phosphorylation of A. fumigatus CnaA in vivo at four clustered serine residues (S406, S408, S410 and S413) in the SPRR. Mutation of the SPRR serine residues to block phosphorylation led to significant hyphal growth and virulence defects, indicating the requirement of calcineurin phosphorylation at the SPRR for its activity and function. Complementation analyses of the A. fumigatus ΔcnaA strain with cnaA homologs from the pathogenic basidiomycete Cryptococcus neoformans, the pathogenic zygomycete Mucor circinelloides, the closely related filamentous fungi Neurospora crassa, and the plant pathogen Magnaporthe grisea, revealed filamentous fungal-specific phosphorylation of CnaA in the SPRR and SPRR homology-dependent restoration of hyphal growth. Surprisingly, circular dichroism studies revealed that, despite proximity to the CaM-binding domain of CnaA, phosphorylation of the SPRR does not alter protein folding following CaM binding. Furthermore, mutational analyses in the catalytic domain, CnaB-binding helix, and the CaM-binding domains revealed that while the conserved PxIxIT substrate binding motif in CnaA is indispensable for septal localization, CaM is required for its function at the hyphal septum but not for septal localization. We defined an evolutionarily conserved novel mode of calcineurin regulation by phosphorylation in filamentous fungi in a region absent in humans. These findings suggest the possibility of harnessing this unique SPRR for innovative antifungal drug design to combat invasive aspergillosis.
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Affiliation(s)
- Praveen R. Juvvadi
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Christopher Gehrke
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Jarrod R. Fortwendel
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Frédéric Lamoth
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Erik J. Soderblom
- Duke Proteomics Facility, Institute for Genome Sciences and Policy, Duke University, Durham, North Carolina, United States of America
| | - Erik C. Cook
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, Kentucky, United States of America
| | - Michael A. Hast
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Yohannes G. Asfaw
- Division of Laboratory Animal Resources, Duke University Medical Center, Durham, North Carolina, United States of America
| | - M. Arthur Moseley
- Duke Proteomics Facility, Institute for Genome Sciences and Policy, Duke University, Durham, North Carolina, United States of America
| | - Trevor P. Creamer
- Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, Kentucky, United States of America
| | - William J. Steinbach
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail:
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The immune interplay between the host and the pathogen in Aspergillus fumigatus lung infection. BIOMED RESEARCH INTERNATIONAL 2013; 2013:693023. [PMID: 23984400 PMCID: PMC3745895 DOI: 10.1155/2013/693023] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 06/14/2013] [Indexed: 12/22/2022]
Abstract
The interplay between Aspergillus fumigatus and the host immune response in lung infection has been subject of studies over the last years due to its importance in immunocompromised patients. The multifactorial virulence factors of A. fumigatus are related to the fungus biological characteristics, for example, structure, ability to grow and adapt to high temperatures and stress conditions, besides capability of evading the immune system and causing damage to the host. In this context, the fungus recognition by the host innate immunity occurs when the pathogen disrupts the natural and chemical barriers followed by the activation of acquired immunity. It seems clear that a Th1 response has a protective role, whereas Th2 reactions are often associated with higher fungal burden, and Th17 response is still controversial. Furthermore, a fine regulation of the effector immunity is required to avoid excessive tissue damage associated with fungal clearance, and this role could be attributed to regulatory T cells. Finally, in this work we reviewed the aspects involved in the complex interplay between the host immune response and the pathogen virulence factors, highlighting the immunological issues and the importance of its better understanding to the development of novel therapeutic approaches for invasive lung aspergillosis.
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Genetic bypass of Aspergillus nidulans crzA function in calcium homeostasis. G3-GENES GENOMES GENETICS 2013; 3:1129-41. [PMID: 23665873 PMCID: PMC3704241 DOI: 10.1534/g3.113.005983] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
After dephosphorylation by the phosphatase calcineurin, the fungal transcription factor CrzA enters the nucleus and activates the transcription of genes responsible for calcium homeostasis and many other calcium-regulated activities. A lack of CrzA confers calcium-sensitivity to the filamentous fungus Aspergillus nidulans. To further understand calcium signaling in filamentous fungi and to identify genes that interact genetically with CrzA, we selected for mutations that were able to suppress crzAΔ calcium intolerance and identified three genes. Through genetic mapping, gene sequencing, and mutant rescue, we were able to identify these as cnaB (encoding the calcineurin regulatory subunit), folA (encoding an enzyme involved in folic acid biosynthesis, dihydroneopterin aldolase), and scrC (suppression of crzA-, encoding a hypothetical protein). By using a calcium indicator, Fluo-3, we were able to determine that the wild-type and the suppressor strains were either able to regulate intracellular calcium levels or were able to take up and or store calcium correctly. The increased expression of calcium transporters, pmcA and/or pmcB, in suppressor mutants possibly enabled tolerance to high levels of calcium. Our results suggest that a cnaB suppressor mutation confers calcium tolerance to crzAΔ strains through restoration of calcium homeostasis. These results stress that in A. nidulans there are calcineurin-dependent and CrzA-independent pathways. In addition, it is possible that CrzA is able to contribute to the modulation of folic acid biosynthesis.
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Hernández-Ortiz P, Espeso EA. Phospho-regulation and nucleocytoplasmic trafficking of CrzA in response to calcium and alkaline-pH stress in Aspergillus nidulans. Mol Microbiol 2013; 89:532-51. [PMID: 23772954 DOI: 10.1111/mmi.12294] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2013] [Indexed: 12/20/2022]
Abstract
Tolerance to abiotic stresses by microorganisms require of appropriate signalling and regulatory pathways. Calcineurin phosphatases mediate calcium-dependent signalling pathways which are widely distributed among phylogeny. In Saccharomyces cerevisiae, calcineurin mediates the post-translational modification of downstream effectors, most of them transcription factors, being the best-characterized calcineurin-regulated zinc-finger factor 1, Crz1p. Here we study the signalling process of CrzA, a filamentous fungal Crz orthologue, in response to calcium and ambient-pH alkalinization. In Aspergillus nidulans resting cells CrzA locates in the cytoplasm being excluded from nuclei. CrzA is a phospho-protein and upon calcium, manganese or alkaline-pH stresses, accumulates in nuclei in a calcineurin-dependent manner. Functional analysis of CrzA defined the presence of a nuclear-export and two nuclear-localization signals as well as a PSINVE sequence that constitutes the major calcineurin-docking domain. First 450 amino acids of CrzA contain these functional motifs and in this region is where phosphorylated residues locate. Different phosphorylation steps are identified in CrzA and activities of casein kinase 1 homologue, CkiA, and of glycogen synthase kinase-3β, identified for the first time here as GskA, are involved. The phospho-signalling process and nucleocytoplasmic trafficking of CrzA shows similarities to those described in yeast for Crz1p homologues and of NFATs in mammals.
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Affiliation(s)
- Patricia Hernández-Ortiz
- Department of Cellular and Molecular Biology, Centro Investigaciones Biológicas, CSIC, Ramiro de Maeztu, 9, Madrid, 28040, Spain
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Herbst S, Shah A, Carby M, Chusney G, Kikkeri N, Dorling A, Bignell E, Shaunak S, Armstrong-James D. A new and clinically relevant murine model of solid-organ transplant aspergillosis. Dis Model Mech 2013; 6:643-51. [PMID: 23264562 PMCID: PMC3634648 DOI: 10.1242/dmm.010330] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 12/16/2012] [Indexed: 12/11/2022] Open
Abstract
Invasive fungal infections (IFIs) are a major cause of death in organ transplant patients. The murine hydrocortisone-mediated immunosuppression model of pulmonary aspergillosis is commonly used to characterise IFIs in these patients. However, this model does not take into account the effects of calcineurin inhibitors on transplant immunity to IFIs or the fungal calcineurin pathway, which is required for both virulence and antifungal drug resistance. To address these two issues, a new and clinically relevant transplant immunosuppression model of tacrolimus (FK506) and hydrocortisone-associated pulmonary aspergillosis was developed. We first characterised IFIs in 406 patients with a lung transplant. This showed that all of the patients with pulmonary aspergillosis were immunosuppressed with calcineurin inhibitors and steroids. Murine pharmacokinetic studies demonstrated that an ideal dose of 1 mg/kg/day of FK506 intraperitoneally produced blood trough levels in the human therapeutic range (5-12 ng/ml). There was increased mortality from pulmonary aspergillosis in a transplant-relevant immunosuppression model using both FK506 and hydrocortisone as compared with immunosuppression using hydrocortisone only. Lung histopathology showed neutrophil invasion and tracheobronchitis that was associated with reduced lung tumour necrosis factor-α (TNFα), JE (homologue of human MCP-1) and KC (homologue of human IL-8) at 24 hours, but increased lung TNFα, JE and KC at 48 hours when fungal burden was high. Furthermore, FK506 directly impaired fungal killing in alveolar macrophages in vitro, with FK506-mediated inhibition of the radial growth of Aspergillus fumigatus in vitro occurring at the low concentration of 5 ng/ml. Taken together, these findings show that the immunosuppressive activity of FK506 outweighs its antifungal activity in vivo. These observations demonstrate that FK506 impairs innate immune responses and leads to an incremental increase in susceptibility to IFIs when it is combined with steroids. This new and clinically relevant mouse model of invasive aspergillosis is a valuable addition to the further study of both fungal immunity and antifungal therapy in organ transplantation.
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Affiliation(s)
- Susanne Herbst
- Departments of Medicine, Infectious Diseases and Immunity, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Anand Shah
- Departments of Medicine, Infectious Diseases and Immunity, Imperial College London, Du Cane Road, London W12 0NN, UK
- The Royal Brompton and Harefield NHS Trust, Sidney Street, London SW3 6NP, UK
| | - Martin Carby
- The Royal Brompton and Harefield NHS Trust, Sidney Street, London SW3 6NP, UK
| | - Gary Chusney
- Leslie Brent Laboratory, Imperial College Healthcare NHS Trust, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Naresh Kikkeri
- Department of Pathology, Imperial College Healthcare NHS Trust, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Anthony Dorling
- MRC Centre for Transplantation, Kings College London, Guy’s Hospital, Great Maze Pond, London SE1 9RT, UK
| | - Elaine Bignell
- Department of Microbiology, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Sunil Shaunak
- Departments of Medicine, Infectious Diseases and Immunity, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Darius Armstrong-James
- Departments of Medicine, Infectious Diseases and Immunity, Imperial College London, Du Cane Road, London W12 0NN, UK
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Zhang H, Guo J, Voegele RT, Zhang J, Duan Y, Luo H, Kang Z. Functional characterization of calcineurin homologs PsCNA1/PsCNB1 in Puccinia striiformis f. sp. tritici using a host-induced RNAi system. PLoS One 2012; 7:e49262. [PMID: 23139840 PMCID: PMC3490909 DOI: 10.1371/journal.pone.0049262] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 10/04/2012] [Indexed: 11/29/2022] Open
Abstract
Calcineurin plays a key role in morphogenesis, pathogenesis and drug resistance in most fungi. However, the function of calcineurin genes in Puccinia striiformis f. sp. tritici (Pst) is unclear. We identified and characterized the calcineurin genes PsCNA1 and PsCNB1 in Pst. Phylogenetic analyses indicate that PsCNA1 and PsCNB1 form a calcium/calmodulin regulated protein phosphatase belonging to the calcineurin heterodimers composed of subunits A and B. Quantitative RT-PCR analyses revealed that both PsCNA1 and PsCNB1 expression reached their maximum in the stage of haustorium formation, which is one day after inoculation. Using barely stripe mosaic virus (BSMV) as a transient expression vector in wheat, the expression of PsCNA1 and PsCNB1 in Pst was suppressed, leading to slower extension of fungal hyphae and reduced production of urediospores. The immune-suppressive drugs cyclosporin A and FK506 markedly reduced the germination rates of urediospores, and when germination did occur, more than two germtubes were produced. These results suggest that the calcineurin signaling pathway participates in stripe rust morphogenetic differentiation, especially the formation of haustoria during the early stage of infection and during the production of urediospores. Therefore PsCNA1 and PsCNB1 can be considered important pathogenicity genes involved in the wheat-Pst interaction.
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Affiliation(s)
- Hong Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A & F University, Yangling, Shaanxi, People's Republic of China
| | - Jun Guo
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A & F University, Yangling, Shaanxi, People's Republic of China
| | - Ralf T. Voegele
- Fachgebiet Phytopathologie, Institut für Phytomedizin, Fakultät Agrarwissenschaften, Universität Hohenheim, Stuttgart, Germany
| | - Jinshan Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A & F University, Yangling, Shaanxi, People's Republic of China
| | - Yinghui Duan
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Sciences, Northwest A & F University, Yangling, Shaanxi, People's Republic of China
| | - Huaiyong Luo
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A & F University, Yangling, Shaanxi, People's Republic of China
| | - Zhensheng Kang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A & F University, Yangling, Shaanxi, People's Republic of China
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The Ca2+/calcineurin-dependent signaling pathway in the gray mold Botrytis cinerea: the role of calcipressin in modulating calcineurin activity. PLoS One 2012; 7:e41761. [PMID: 22844520 PMCID: PMC3402410 DOI: 10.1371/journal.pone.0041761] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 06/25/2012] [Indexed: 12/31/2022] Open
Abstract
In the gray mold fungus Botrytis cinerea the Gα subunit Bcg1 of a heterotrimeric G protein is an upstream activator of the Ca2+/calmodulin-dependent phosphatase calcineurin. In this study we focused on the functional characterization of the catalytic subunit of calcineurin (BcCnA) and its putative regulator calcipressin (BcRcn1). We deleted the genes encoding both proteins to examine their role concerning growth, differentiation and virulence. The ΔbccnA mutant shows a severe growth defect, does not produce conidia and is avirulent, while the loss of BcRcn1 caused retardation of hyphal growth and delayed infection of host plants, but had no impact on conidiation and sclerotia formation. Expression of several calcineurin-dependent genes and bccnA itself is positively affected by BcRcn1. Complementation of the Δbcrcn1 mutant with a GFP-BcRcn1 fusion construct revealed that BcRcn1 is localized in the cytoplasm and accumulates around the nuclei. Furthermore, we showed that BcCnA physically interacts with BcRcn1 and the regulatory subunit of calcineurin, BcCnB. We investigated the impact of several protein domains characteristic for modulation and activation of BcCnA via BcRcn1, such as the phosphorylation sites and the calcineurin-docking site, by physical interaction studies between BcCnA and wild-type and mutated copies of BcRcn1. Based on the observed phenotypes we conclude that BcRcn1 acts as a positive modulator of BcCnA and the Ca2+/calcineurin-mediated signal transduction in B. cinerea, and that both proteins regulate fungal development and virulence.
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Dinamarco TM, Freitas FZ, Almeida RS, Brown NA, dos Reis TF, Ramalho LNZ, Savoldi M, Goldman MHS, Bertolini MC, Goldman GH. Functional characterization of an Aspergillus fumigatus calcium transporter (PmcA) that is essential for fungal infection. PLoS One 2012; 7:e37591. [PMID: 22649543 PMCID: PMC3359301 DOI: 10.1371/journal.pone.0037591] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Accepted: 04/22/2012] [Indexed: 02/01/2023] Open
Abstract
Aspergillus fumigatus is a primary and opportunistic pathogen, as well as a major allergen, of mammals. The Ca(+2)-calcineurin pathway affects virulence, morphogenesis and antifungal drug action in A. fumigatus. Here, we investigated three components of the A. fumigatus Ca(+2)-calcineurin pathway, pmcA,-B, and -C, which encode calcium transporters. We demonstrated that CrzA can directly control the mRNA accumulation of the pmcA-C genes by binding to their promoter regions. CrzA-binding experiments suggested that the 5'-CACAGCCAC-3' and 5'-CCCTGCCCC-3' sequences upstream of pmcA and pmcC genes, respectively, are possible calcineurin-dependent response elements (CDREs)-like consensus motifs. Null mutants were constructed for pmcA and -B and a conditional mutant for pmcC demonstrating pmcC is an essential gene. The ΔpmcA and ΔpmcB mutants were more sensitive to calcium and resistant to manganese and cyclosporin was able to modulate the sensitivity or resistance of these mutants to these salts, supporting the interaction between calcineurin and the function of these transporters. The pmcA-C genes have decreased mRNA abundance into the alveoli in the ΔcalA and ΔcrzA mutant strains. However, only the A. fumigatus ΔpmcA was avirulent in the murine model of invasive pulmonary aspergillosis.
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Affiliation(s)
- Taísa Magnani Dinamarco
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | | | - Ricardo S. Almeida
- Department of Microbiology, University of Londrina, Londrina, Paraná, Brazil
| | - Neil Andrew Brown
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Thaila Fernanda dos Reis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | | | - Marcela Savoldi
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Maria Helena S. Goldman
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | | | - Gustavo Henrique Goldman
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol – CTBE, Campinas, São Paulo, Brazil
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
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