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Sharma A, Homayoon A, Weyler M, Frazer C, Ramírez-Zavala B, Morschhäuser J, Bennett RJ. Transcriptional control of C. albicans white-opaque switching and modulation by environmental cues and strain background. mBio 2025; 16:e0058125. [PMID: 40202334 PMCID: PMC12077150 DOI: 10.1128/mbio.00581-25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2025] [Accepted: 03/10/2025] [Indexed: 04/10/2025] Open
Abstract
The opportunistic fungal pathogen Candida albicans can undergo cellular transitions in response to environmental cues that impact its lifestyle and its interactions with the human host. This is exemplified by the white-opaque switch, which is a heritable transition between two phenotypic states that is regulated by a highly interconnected network of transcription factors (TFs). To obtain greater understanding of the transcriptional regulation of the switch, we generated a genome-wide, tetracycline-inducible TF library in the WO-1 strain background and identified those TFs whose forced expression induces white cells to switch to the opaque state. This set of opaque-inducing TFs was also evaluated for their ability to induce switching in a second strain background, that of the standard reference strain SC5314, as well as during growth on different laboratory media. These experiments identify 14 TFs that can drive white-to-opaque switching when overexpressed but that do so in a highly strain- and media-specific manner. In particular, changes in pH, amino acids, and zinc concentrations had marked effects on the ability of TFs to drive phenotypic switching. These results provide insights into the complex transcriptional regulation of switching in C. albicans and reveal that an interplay between genetic and environmental factors determines TF function and cell fate.IMPORTANCEThe white-opaque switch in Candida albicans represents a model system for understanding an epigenetic switch in a eukaryotic pathogen. Here, we generated an inducible library of the set of transcription factors (TFs) present in C. albicans and identify 14 TFs that can drive the white-to-opaque transition when ectopically expressed. We demonstrate that several of these TFs induce the switch in a highly strain- and media-specific manner. This highlights that both strain background and changes in experimental conditions (including different water sources) can profoundly impact the phenotypic consequences of TF overexpression. Moreover, the inducible TF library provides an invaluable tool for the further analysis of TF function in this important human pathogen.
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Affiliation(s)
- Anupam Sharma
- Department of Molecular and Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| | - Ameen Homayoon
- Department of Molecular and Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| | - Michael Weyler
- Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Bavaria, Germany
| | - Corey Frazer
- Department of Molecular and Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| | - Bernardo Ramírez-Zavala
- Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Bavaria, Germany
| | - Joachim Morschhäuser
- Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Bavaria, Germany
| | - Richard J. Bennett
- Department of Molecular and Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
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2
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Crouse J, Sellers S, Wawrousek K, Sabino RM. Biopolymers from Sugar Beet Molasses: Isolation, Characterization, and Bioactive Properties. ACS OMEGA 2025; 10:12002-12013. [PMID: 40191357 PMCID: PMC11966254 DOI: 10.1021/acsomega.4c09633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2024] [Revised: 02/21/2025] [Accepted: 03/06/2025] [Indexed: 04/09/2025]
Abstract
Utilizing the natural biological properties of plant byproducts for a variety of applications presents the opportunity to combine nature's benefits with sustainable innovation. For this study, sugar beet molasses polymer (SBMP) was isolated from a byproduct of sugar beet processing. The SBMP was analyzed to determine its suitability for potential uses in biomedicine, cosmetics, and antimicrobial coatings. To determine whether the SBMP was indeed a polymer, MALDI-TOF MS was performed. The chemical composition of the SBMP was characterized using XPS, 1H NMR, 13C NMR, and FTIR. The characterization concluded that the SBMP contains phenolic and hydroxide groups. The presence of these groups was further supported by the SBMP's high antioxidant activity (∼80% RSA). The SBMP also demonstrated antimicrobial activity against Rhodococcus erythropolis (∼80% GI at 1 mg/mg SBMP), Escherichia coli (∼80% GI at 1 mg/mg SBMP), and Saccharomyces cerevisiae (∼38% GI at 1 mg/mg SBMP). Additionally, the SBMP showed no toxicity to human adipose-derived stem cells (ADSC) at concentrations up to 0.5 mg/mL and supported healthy cellular growth. Due to its strong antimicrobial and antioxidant activity, SBMP could be used in a variety of biomedical, cosmetic, and coating applications.
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Affiliation(s)
| | | | - Karen Wawrousek
- Department of Chemical and
Biomedical Engineering, University of Wyoming, Laramie 82071-0333, United States
| | - Roberta M. Sabino
- Department of Chemical and
Biomedical Engineering, University of Wyoming, Laramie 82071-0333, United States
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3
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Hossain S, Liu Z, Robbins N, Cowen LE. Exploring the differential localization of protein kinase A isoforms in Candida albicans. mSphere 2025; 10:e0103724. [PMID: 39998251 PMCID: PMC11934313 DOI: 10.1128/msphere.01037-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2024] [Accepted: 01/28/2025] [Indexed: 02/26/2025] Open
Abstract
The cAMP-dependent protein kinase A (PKA) plays important roles in a wide range of biological processes in eukaryotic organisms. In the fungal pathogen Candida albicans, PKA is a critical regulator of morphological transitions, which are a key virulence trait. PKA is composed of two catalytic isoforms, Tpk1 and Tpk2, which are often thought to act together in a complex with the regulatory subunit Bcy1. Although Tpk1 and Tpk2 have some redundant functions, they also have distinct cellular functions for which the mechanistic underpinnings remain largely elusive. Here, we constructed functional GFP-tagged fusion proteins for Tpk1, Tpk2, and Bcy1 to explore the localization of PKA isoforms. We observed that the PKA holoenzyme is mainly found in the cytoplasm, as Bcy1 is always excluded from the nucleus. Under glucose-replete conditions, both Tpk1 and Tpk2 translocate into the nucleus from the cytosol. In the presence of glycerol, Tpk1 resides in the cytosol, whereas Tpk2 and Bcy1 become enriched on the vacuolar membrane. As the C-terminal domains of Tpk are highly homologous, we investigated the localization and function of hybrid Tpk proteins with exchanged N-terminal domains. We found the catalytic C-terminus of Tpk1 is required for morphogenesis in solid medium, whereas the C-terminus of Tpk2 is critical for filamentation in liquid. Interestingly, the N-terminus of Tpk2 drives its localization to the vacuolar membrane. Our work highlights environmentally contingent localization patterns for the PKA subunits and suggests that the nuclear localization of Tpk is not sufficient to induce the filamentation program in a leading fungal pathogen of humans.IMPORTANCEFungal pathogens have a devastating impact on human health worldwide. They infect billions of people and kill more than 2.5 million per year. Candida albicans is a leading human fungal pathogen responsible for causing life-threatening systemic disease in immunocompromised individuals. A key virulence trait in C. albicans is the ability to switch between yeast and filamentous forms. The conserved protein kinase A (PKA) regulates diverse functions in the cell, including growth and filamentation. Although PKA has been studied in C. albicans for decades, the subcellular localization of PKA has not been thoroughly investigated. Here, we constructed functional GFP-tagged PKA subunits to explore their localization. We identified differential localization patterns for the PKA subunits that are carbon-source dependent and report that these proteins localize into foci in response to diverse environmental stresses. These findings further our understanding of a critical regulator of growth and virulence in C. albicans.
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Affiliation(s)
- Saif Hossain
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Zhongle Liu
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Leah E. Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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4
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Tosiano MA, Lanni F, Mitchell AP, McManus CJ. Roles of P-body factors in Candida albicans filamentation and stress response. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2025:2024.07.09.602714. [PMID: 40161774 PMCID: PMC11952329 DOI: 10.1101/2024.07.09.602714] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 04/02/2025]
Abstract
Hyphal growth is strongly associated with virulence in the human fungal pathogen Candida albicans. While hyphal transcriptional networks have been the subject of intense study, relatively little is known about post-transcriptional regulation. Previous work reported that P-Body (PB) factors Dhh1 and Edc3 were required for C. albicans virulence and filamentation, suggesting an essential role for post-transcriptional regulation of these processes. However, the molecular roles of these factors have not been determined. To further study the function of PB factors in filamentation, we generated homozygous deletions of DHH1 and EDC3 in diverse prototrophic clinical strains using transient CRISPR-Cas9. Homozygous DHH1 deletion strongly impaired growth, altered filamentation, and exhibited unusual colony morphology in response to heat stress in five strain backgrounds. Using RNA-seq, we found DHH1 deletion disrupts the regulation of thousands of genes under both yeast and hyphal growth conditions in SC5314 and P57055. This included upregulation of many stress response genes in the absence of external stress, similar to deletion of the S. cerevisiae DHH1 homolog. In contrast, we found EDC3 was not required for heat tolerance or filamentation in diverse strains. These results support a model in which DHH1, but not EDC3, represses hyphal stress response transcripts in yeast and remodels the transcriptome during filamentation. Our work supports distinct requirements for specific mRNA decay factors, bolstering evidence for post-transcriptional regulation of filamentation in C. albicans.
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Affiliation(s)
- Melissa A. Tosiano
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Frederick Lanni
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Aaron P. Mitchell
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
| | - C. Joel McManus
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
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5
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Tosiano MA, Lanni F, Mitchell AP, McManus CJ. Roles of P-body factors in Candida albicans filamentation and stress response. PLoS Genet 2025; 21:e1011632. [PMID: 40096135 PMCID: PMC11975087 DOI: 10.1371/journal.pgen.1011632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2024] [Revised: 04/07/2025] [Accepted: 02/20/2025] [Indexed: 03/19/2025] Open
Abstract
Hyphal growth is strongly associated with virulence in the human fungal pathogen Candida albicans. While hyphal transcriptional networks have been the subject of intense study, relatively little is known about post-transcriptional regulation. Previous work reported that P-Body (PB) factors Dhh1 and Edc3 were required for C. albicans virulence and filamentation, suggesting an essential role for post-transcriptional regulation of these processes. However, the molecular roles of these factors have not been determined. To further study the function of PB factors in filamentation, we generated homozygous deletions of DHH1 and EDC3 in diverse prototrophic clinical strains using transient CRISPR-Cas9. Homozygous DHH1 deletion strongly impaired growth, altered filamentation, and exhibited unusual colony morphology in response to heat stress in five strain backgrounds. Using RNA-seq, we found DHH1 deletion disrupts the regulation of thousands of genes under both yeast and hyphal growth conditions in SC5314 and P57055. This included upregulation of many stress response genes in the absence of external stress, similar to deletion of the S. cerevisiae DHH1 homolog. In contrast, we found EDC3 was not required for heat tolerance or filamentation in diverse strains. These results support a model in which DHH1, but not EDC3, represses hyphal stress response transcripts in yeast and remodels the transcriptome during filamentation. Our work supports distinct requirements for specific mRNA decay factors, bolstering evidence for post-transcriptional regulation of filamentation in C. albicans.
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Affiliation(s)
- Melissa A. Tosiano
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Frederick Lanni
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Aaron P. Mitchell
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
| | - C. Joel McManus
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
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6
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Guo S, Du J, Li D, Xiong J, Chen Y. Versatile xylose and arabinose genetic switches development for yeasts. Metab Eng 2025; 87:21-36. [PMID: 39537022 DOI: 10.1016/j.ymben.2024.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2024] [Revised: 10/31/2024] [Accepted: 11/10/2024] [Indexed: 11/16/2024]
Abstract
Inducible transcription systems are essential tools in genetic engineering, where tight control, strong inducibility and fast response with cost-effective inducers are highly desired. However, existing systems in yeasts are rarely used in large-scale fermentations due to either cost-prohibitive inducers or incompatible performance. Here, we developed powerful xylose and arabinose induction systems in Saccharomyces cerevisiae, utilizing eukaryotic activators XlnR and AraRA from Aspergillus species and bacterial repressors XylR and AraRR. By integrating these signals into a highly-structured synthetic promoter, we created dual-mode systems with strong outputs and minimal leakiness. These systems demonstrated over 4000- and 300-fold regulation with strong activation and rapid response. The dual-mode xylose system was fully activated by xylose-rich agricultural residues like corncob hydrolysate, outperforming existing systems in terms of leakiness, inducibility, dynamic range, induction rate, and growth impact on host. We validated their utility in metabolic engineering with high-titer linalool production and demonstrated the transferability of the XlnR-based xylose induction system to Pichia pastoris, Candida glabrata and Candida albicans. This work provides robust genetic switches for yeasts and a general strategy for integrating activation-repression signals into synthetic promoters to achieve optimal performance.
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Affiliation(s)
- Shuhui Guo
- Key Laboratory of Quantitative Synthetic Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Juhua Du
- Key Laboratory of Quantitative Synthetic Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Donghan Li
- Key Laboratory of Quantitative Synthetic Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China; College of Biological Science, China Agricultural University, Beijing, 100193, China
| | - Jinghui Xiong
- Key Laboratory of Quantitative Synthetic Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Ye Chen
- Key Laboratory of Quantitative Synthetic Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
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7
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Naseem S, Zahumenský J, Lanze CE, Douglas LM, Malínský J, Konopka JB. The Cwr1 protein kinase localizes to the plasma membrane and mediates resistance to cell wall stress in Candida albicans. mSphere 2024; 9:e0039124. [PMID: 39611854 DOI: 10.1128/msphere.00391-24] [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: 05/09/2024] [Accepted: 11/07/2024] [Indexed: 11/30/2024] Open
Abstract
The plasma membrane is critical for the virulence of the human fungal pathogen Candida albicans. In addition to functioning as a protective barrier, the plasma membrane plays dynamic roles in a wide range of functions needed for virulence including nutrient uptake, cell wall synthesis, morphogenesis, resistance to stress, and invasive hyphal growth. Screening a collection of C. albicans mutants identified an understudied gene that is important for invasive hyphal growth, which we have termed CWR1 (Cell Wall Regulatory kinase). A mutant strain lacking CWR1 displayed defects in resisting stressful conditions that exacerbate cell wall defects. The Cwr1 protein shows strong similarity to protein kinases, suggesting it plays a regulatory role in coordinating plasma membrane and cell wall functions. A Cwr1-green fluorescent protein (GFP) fusion protein localized to punctate patches associated with the plasma membrane that partially overlapped Membrane Compartment of Can1 (MCC)/eisosome domains. In contrast to the static MCC/eisosome domains, the Cwr1-GFP patches were very dynamic. Truncation mutants lacking C-terminal sequences distal to the protein kinase domain failed to show detectable localization at the plasma membrane. Surprisingly, these mutant strains did not show the defects of a cwr1Δ mutant, suggesting that localization to punctate patches associated with the plasma membrane is not essential for Cwr1 function. Altogether, these data indicate that Cwr1 contributes to the regulation of plasma membrane functions that promote proper morphogenesis and resistance to cell wall stress, both of which are important for C. albicans virulence. IMPORTANCE The ability of Candida albicans to grow invasively in the host and resist stress is critical for it to be an effective human pathogen. Identifying the genes that promote these processes is important for developing new strategies to block infection. Therefore, genetic methods were used in this study to identify a novel gene that is needed for invasive growth and stress resistance (Cell Wall Regulatory kinase [CWR1]). Interestingly, the Cwr1 protein localized to punctate patches in the plasma membrane, some of which co-localized with specialized subdomains of the plasma membrane known as eisosomes that are known to promote stress resistance and invasive growth in the host. Thus, these studies identified a novel regulator of traits that are critical for C. albicans pathogenesis.
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Affiliation(s)
- Shamoon Naseem
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
| | - Jakub Zahumenský
- Department of Functional Organization of Biomembranes, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czechia
| | - Carla E Lanze
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
| | - Lois M Douglas
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
| | - Jan Malínský
- Department of Functional Organization of Biomembranes, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czechia
| | - James B Konopka
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
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8
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Erfaninejad M, Mahmoudabadi A, Hashemzadeh M, Maraghi E, Fatahinia M. Characteristics of Candida albicans Derived From HIV-Positive Individuals With Oral Candidiasis: Genotyping, Phenotypic Variation, Antifungal Susceptibility, and Biofilm Formation. J Clin Lab Anal 2024; 38:e25103. [PMID: 39297751 PMCID: PMC11520941 DOI: 10.1002/jcla.25103] [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: 02/23/2024] [Revised: 08/28/2024] [Accepted: 09/01/2024] [Indexed: 10/30/2024] Open
Abstract
BACKGROUND Oral candidiasis (OC) is one of the most common mucosal infections in those afflicted with HIV/AIDS. This study aimed to provide detailed information on the phenotype, genotype, antifungal susceptibility, and biofilm formation ability of oral Candida albicans isolated from HIV-infected patients with OC. METHODS A total of 25 C. albicans isolates were collected from oral lesions of HIV-infected patients referred to Behavioral Diseases Counseling Center affiliated with Ahvaz Jundishapur University of Medical Sciences, Iran. The antifungal susceptibility testing was done according to CLSI M27 guideline (fourth edition). The crystal violet method was used to evaluate the biofilm formation ability of isolates. Different phenotypes were identified on yeast extract-peptone-dextrose agar medium supplemented with phloxine B. Genotyping analysis of the isolates was performed using high-resolution melting (HRM) assays and ABC genotyping. RESULTS The highest and lowest susceptibility of the C. albicans isolates was found for fluconazole 24 (96%) and ITC 18 (72%), respectively. Forty-eight percent of the isolates had high biofilm formation ability and exhibited gray cell type. The most common genotype was genotype B (52%). HRM analysis of HIS3, EF3, and CDC3 markers showed three, four, and five different groups, respectively. CONCLUSION Investigating the phenotype, antifungal susceptibility and biofilm formation ability of the C. albicans isolates obtained from oral lesions of HIV-infected patients revealed that the dominant genotypes in the current research could cause more serious infections from the oral source. We recommend further research with a larger sample size to determine the molecular epidemiology of C. albicans among HIV patients in Iran.
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Affiliation(s)
- Maryam Erfaninejad
- Department of Basic Medical SciencesShoushtar Faculty of Medical SciencesShoushtarIran
| | - Ali Zarei Mahmoudabadi
- Infectious and Tropical Diseases Research Center, Health Research InstituteAhvaz Jundishapur University of Medical SciencesAhvazIran
- Department of Medical Mycology, School of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran
| | - Mohammad Hashemzadeh
- Infectious and Tropical Diseases Research Center, Health Research InstituteAhvaz Jundishapur University of Medical SciencesAhvazIran
- Department of Microbiology, School of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran
| | - Elham Maraghi
- Department of Biostatistics and Epidemiology, School of HealthAhvaz Jundishapur University of Medical SciencesAhvazIran
| | - Mahnaz Fatahinia
- Infectious and Tropical Diseases Research Center, Health Research InstituteAhvaz Jundishapur University of Medical SciencesAhvazIran
- Department of Medical Mycology, School of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran
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Lanze CE, Konopka JB. Sur7 mediates a novel pathway for PI 4,5P 2 regulation in C. albicans that promotes stress resistance and cell wall morphogenesis. Mol Biol Cell 2024; 35:ar99. [PMID: 38776129 PMCID: PMC11244165 DOI: 10.1091/mbc.e23-08-0324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 05/01/2024] [Accepted: 05/15/2024] [Indexed: 06/11/2024] Open
Abstract
The human fungal pathogen Candida albicans can cause lethal systemic infections due to its ability to resist stress from the host and to undergo invasive hyphal growth. Previous studies showed that plasma membrane MCC/eisosome domains were important for virulence by promoting the ability of Sur7 to mediate normal cell wall morphogenesis and stress resistance. The sur7Δ mutant displayed abnormal clusters of PI4,5P2, suggesting that misregulation of this lipid underlies the sur7Δ phenotype. To test this, we increased PI4,5P2 levels by deleting combinations of the three PI4,5P2 5' phosphatase genes (INP51, INP52, and INP54) and found that some combinations, such as inp51Δ inp52Δ, gave phenotypes similar the sur7Δ mutant. In contrast, deleting one copy of MSS4, the gene that encodes the 5' kinase needed to create PI4,5P2, reduced the abnormal PI4,5P2 clusters and also decreased the abnormal cell wall and stress sensitive phenotypes of the sur7Δ mutant. Additional studies support a model that the abnormal PI4,5P2 patches recruit septin proteins, which in turn promote aberrant cell wall growth. These results identify Sur7 as a novel regulator of PI4,5P2 and highlight the critical role of PI4,5P2 in the regulation of C. albicans virulence properties.
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Affiliation(s)
- Carla E. Lanze
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY 11794-5222
| | - James B. Konopka
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY 11794-5222
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10
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de Andrade IB, Figueiredo-Carvalho MHG, Chaves ALDS, Coelho RA, Almeida-Silva F, Zancopé-Oliveira RM, Frases S, Brito-Santos F, Almeida-Paes R. Metabolic and phenotypic plasticity may contribute for the higher virulence of Trichosporon asahii over other Trichosporonaceae members. Mycoses 2022; 66:430-440. [PMID: 36564594 DOI: 10.1111/myc.13562] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 12/15/2022] [Accepted: 12/20/2022] [Indexed: 12/25/2022]
Abstract
BACKGROUND The Trichosporonaceae family comprises a large number of basidiomycetes widely distributed in nature. Some of its members, especially Trichosporon asahii, have the ability to cause human infections. This ability is related to a series of virulence factors, which include lytic enzymes production, biofilm formation, resistance to oxidising agents, melanin and glucuronoxylomannan in the cell wall, metabolic plasticity and phenotypic switching. The last two are poorly addressed within human pathogenic Trichosporonaceae. OBJECTIVE These factors were herein studied to contribute with the knowledge of these emerging pathogens and to uncover mechanisms that would explain the higher frequency of T. asahii in human infections. METHODS We included 79 clinical isolates phenotypically identified as Trichosporon spp. and performed their molecular identification. Lactate and N-acetyl glucosamine were the carbon sources of metabolic plasticity studies. Morphologically altered colonies after subcultures and incubation at 37°C indicated phenotypic switching. RESULTS AND CONCLUSION The predominant species was T. asahii (n = 65), followed by Trichosporon inkin (n = 4), Apiotrichum montevideense (n = 3), Trichosporon japonicum (n = 2), Trichosporon faecale (n = 2), Cutaneotrichosporon debeurmannianum (n = 1), Trichosporon ovoides (n = 1) and Cutaneotrichosporon arboriforme (n = 1). T. asahii isolates had statistically higher growth on lactate and N-acetylglucosamine and on glucose during the first 72 h of culture. T. asahii, T. inkin and T. japonicum isolates were able to perform phenotypic switching. These results expand the virulence knowledge of Trichosporonaceae members and point for a role for metabolic plasticity and phenotypic switching on the trichosporonosis pathogenesis.
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Affiliation(s)
- Iara Bastos de Andrade
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.,Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos agas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Alessandra Leal da Silva Chaves
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.,Laboratório de Análises Clínicas, Instituto Nacional de Câncer, Rio de Janeiro, Brazil
| | - Rowena Alves Coelho
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Fernando Almeida-Silva
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Rosely Maria Zancopé-Oliveira
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Susana Frases
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos agas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Rede Micologia RJ, FAPERJ, Rio de Janeiro, Brazil
| | | | - Rodrigo Almeida-Paes
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.,Rede Micologia RJ, FAPERJ, Rio de Janeiro, Brazil
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11
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Jain BK, Wagner AS, Reynolds TB, Graham TR. Lipid Transport by Candida albicans Dnf2 Is Required for Hyphal Growth and Virulence. Infect Immun 2022; 90:e0041622. [PMID: 36214556 PMCID: PMC9670988 DOI: 10.1128/iai.00416-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 09/19/2022] [Indexed: 11/20/2022] Open
Abstract
Candida albicans is a common cause of human mucosal yeast infections, and invasive candidiasis can be fatal. Antifungal medications are limited, but those targeting the pathogen cell wall or plasma membrane have been effective. Therefore, virulence factors controlling membrane biogenesis are potential targets for drug development. P4-ATPases contribute to membrane biogenesis by selecting and transporting specific lipids from the extracellular leaflet to the cytoplasmic leaflet of the bilayer to generate lipid asymmetry. A subset of heterodimeric P4-ATPases, including Dnf1-Lem3 and Dnf2-Lem3 from Saccharomyces cerevisiae, transport phosphatidylcholine (PC), phosphatidylethanolamine (PE), and the sphingolipid glucosylceramide (GlcCer). GlcCer is a critical lipid for Candida albicans polarized growth and virulence, but the role of GlcCer transporters in virulence has not been explored. Here, we show that the Candida albicans Dnf2 (CaDnf2) requires association with CaLem3 to form a functional transporter and flip fluorescent derivatives of GlcCer, PC, and PE across the plasma membrane. Mutation of conserved substrate-selective residues in the membrane domain strongly abrogates GlcCer transport and partially disrupts PC transport by CaDnf2. Candida strains harboring dnf2-null alleles (dnf2ΔΔ) or point mutations that disrupt substrate recognition exhibit defects in yeast-to-hypha growth transition, filamentous growth, and virulence in systemically infected mice. The influence of CaDNF1 deletion on the morphological phenotypes is negligible, although the dnf1ΔΔ dnf2ΔΔ strain was less virulent than the dnf2ΔΔ strain. These results indicate that the transport of GlcCer and/or PC by plasma membrane P4-ATPases is important for the pathogenicity of Candida albicans.
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Affiliation(s)
- Bhawik K. Jain
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Andrew S. Wagner
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
| | - Todd B. Reynolds
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
| | - Todd R. Graham
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
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12
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A Fungal Transcription Regulator of Vacuolar Function Modulates Candida albicans Interactions with Host Epithelial Cells. mBio 2021; 12:e0302021. [PMID: 34781731 PMCID: PMC8593675 DOI: 10.1128/mbio.03020-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Microorganisms typically maintain cellular homeostasis despite facing large fluctuations in their surroundings. Microbes that reside on human mucosal surfaces may experience significant variations in nutrient and ion availability as well as pH. Whether the mechanisms employed by these microbial cells to sustain homeostasis directly impact on the interplay with the host’s mucosae remains unclear. Here, we report that the previously uncharacterized transcription regulator ZCF8 in the human-associated yeast Candida albicans maintains vacuole homeostasis when the fungus faces fluctuations in nitrogen. Genome-wide identification of genes directly regulated by Zcf8p followed by fluorescence microscopy to define their subcellular localization uncovered the fungal vacuole as a top target of Zcf8p regulation. Deletion and overexpression of ZCF8 resulted in alterations in vacuolar morphology and luminal pH and rendered the fungus resistant or susceptible to nigericin and brefeldin A, two drugs that impair vacuole and associated functions. Furthermore, we establish that the regulator modulates C. albicans attachment to epithelial cells in a manner that depends on the status of the fungal vacuole. Our findings, therefore, suggest that fungal vacuole physiology regulation is intrinsically linked to, and shapes to a significant extent, the physical interactions that Candida cells establish with mammalian mucosal surfaces.
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13
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Van Genechten W, Van Dijck P, Demuyser L. Fluorescent toys 'n' tools lighting the way in fungal research. FEMS Microbiol Rev 2021; 45:fuab013. [PMID: 33595628 PMCID: PMC8498796 DOI: 10.1093/femsre/fuab013] [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: 11/06/2020] [Accepted: 02/14/2021] [Indexed: 12/13/2022] Open
Abstract
Although largely overlooked compared to bacterial infections, fungal infections pose a significant threat to the health of humans and other organisms. Many pathogenic fungi, especially Candida species, are extremely versatile and flexible in adapting to various host niches and stressful situations. This leads to high pathogenicity and increasing resistance to existing drugs. Due to the high level of conservation between fungi and mammalian cells, it is hard to find fungus-specific drug targets for novel therapy development. In this respect, it is vital to understand how these fungi function on a molecular, cellular as well as organismal level. Fluorescence imaging allows for detailed analysis of molecular mechanisms, cellular structures and interactions on different levels. In this manuscript, we provide researchers with an elaborate and contemporary overview of fluorescence techniques that can be used to study fungal pathogens. We focus on the available fluorescent labelling techniques and guide our readers through the different relevant applications of fluorescent imaging, from subcellular events to multispecies interactions and diagnostics. As well as cautioning researchers for potential challenges and obstacles, we offer hands-on tips and tricks for efficient experimentation and share our expert-view on future developments and possible improvements.
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Affiliation(s)
- Wouter Van Genechten
- VIB-KU Leuven Center for Microbiology, Kasteelpark Arenberg 31, 3001 Leuven-heverlee, Belgium
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven-Heverlee, Belgium
- Laboratory for Nanobiology, Department of Chemistry, KU Leuven, Celestijnenlaan 200g, 3001 Leuven-Heverlee, Belgium
| | - Patrick Van Dijck
- VIB-KU Leuven Center for Microbiology, Kasteelpark Arenberg 31, 3001 Leuven-heverlee, Belgium
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven-Heverlee, Belgium
| | - Liesbeth Demuyser
- VIB-KU Leuven Center for Microbiology, Kasteelpark Arenberg 31, 3001 Leuven-heverlee, Belgium
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven-Heverlee, Belgium
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14
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Swidergall M, Solis NV, Millet N, Huang MY, Lin J, Phan QT, Lazarus MD, Wang Z, Yeaman MR, Mitchell AP, Filler SG. Activation of EphA2-EGFR signaling in oral epithelial cells by Candida albicans virulence factors. PLoS Pathog 2021; 17:e1009221. [PMID: 33471869 PMCID: PMC7850503 DOI: 10.1371/journal.ppat.1009221] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 02/01/2021] [Accepted: 12/05/2020] [Indexed: 12/12/2022] Open
Abstract
During oropharyngeal candidiasis (OPC), Candida albicans invades and damages oral epithelial cells, which respond by producing proinflammatory mediators that recruit phagocytes to foci of infection. The ephrin type-A receptor 2 (EphA2) detects β-glucan and plays a central role in stimulating epithelial cells to release proinflammatory mediators during OPC. The epidermal growth factor receptor (EGFR) also interacts with C. albicans and is known to be activated by the Als3 adhesin/invasin and the candidalysin pore-forming toxin. Here, we investigated the interactions among EphA2, EGFR, Als3 and candidalysin during OPC. We found that EGFR and EphA2 constitutively associate with each other as part of a heteromeric physical complex and are mutually dependent for C. albicans-induced activation. Als3-mediated endocytosis of a C. albicans hypha leads to the formation of an endocytic vacuole where candidalysin accumulates at high concentration. Thus, Als3 potentiates targeting of candidalysin, and both Als3 and candidalysin are required for C. albicans to cause maximal damage to oral epithelial cells, sustain activation of EphA2 and EGFR, and stimulate pro-inflammatory cytokine and chemokine secretion. In the mouse model of OPC, C. albicans-induced production of CXCL1/KC and CCL20 is dependent on the presence of candidalysin and EGFR, but independent of Als3. The production of IL-1α and IL-17A also requires candidalysin but is independent of Als3 and EGFR. The production of TNFα requires Als1, Als3, and candidalysin. Collectively, these results delineate the complex interplay among host cell receptors EphA2 and EGFR and C. albicans virulence factors Als1, Als3 and candidalysin during the induction of OPC and the resulting oral inflammatory response. Oropharyngeal candidiasis occurs when the fungus Candida albicans proliferates in the mouth to a point at which tissue damage occurs. The disease is characterized by fungal invasion of the superficial epithelium and a localized inflammatory response. Two C. albicans virulence factors contribute to the pathogenesis of OPC, Als3 which enables the organism to adhere to and invade host cells, and candidalysin which is a pore-forming toxin that damages host cells. Two epithelial cell receptors, ephrin type-A receptor 2 (EphA2) and the epidermal growth factor receptor (EGFR) are activated by C. albicans. Here, we show that EphA2 and EGFR form part of complex wherein these co-receptors are required to activate each other. Als3 enhances the host cell targeting of candidalysin by stimulating epithelial cell endocytosis of C. albicans, leading to the formation of an endocytic vacuole in which candidalysin accumulates. Thus, Als3 and candidalysin synergize to damage epithelial cells, activate EphA2 and EGFR, and stimulate the production of inflammatory mediators. In the mouse model of OPC, candidalysin elicits of a subset of the oral inflammatory response molecular repertoire. Of the cytokines and chemokines induced by this toxin, some require the activation of EGFR while others are induced independently of EGFR. Collectively, this work provides a deeper understanding of the interactions among C. albicans virulence factors, host cell receptors and immune responses during OPC.
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Affiliation(s)
- Marc Swidergall
- Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, United States of America
- Institute for Infection and Immunity, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, United States of America
- David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- * E-mail: (MS); (SGF)
| | - Norma V. Solis
- Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, United States of America
- Institute for Infection and Immunity, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, United States of America
| | - Nicolas Millet
- Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, United States of America
- Institute for Infection and Immunity, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, United States of America
| | - Manning Y. Huang
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Jianfeng Lin
- Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, United States of America
- Institute for Infection and Immunity, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, United States of America
| | - Quynh T. Phan
- Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, United States of America
- Institute for Infection and Immunity, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, United States of America
| | - Michael D. Lazarus
- Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, United States of America
| | - Zeping Wang
- Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, United States of America
| | - Michael R. Yeaman
- Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, United States of America
- Institute for Infection and Immunity, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, United States of America
- David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- Division of Molecular Medicine, Harbor-UCLA Medical Center, Torrance, California, United States of America
| | - Aaron P. Mitchell
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
| | - Scott G. Filler
- Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance, California, United States of America
- Institute for Infection and Immunity, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, United States of America
- David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
- * E-mail: (MS); (SGF)
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15
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Quantifying the Biophysical Impact of Budding Cell Division on the Spatial Organization of Growing Yeast Colonies. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10175780] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Spatial patterns in microbial colonies are the consequence of cell-division dynamics coupled with cell-cell interactions on a physical media. Agent-based models (ABMs) are a powerful tool for understanding the emergence of large scale structure from these individual cell processes. However, most ABMs have focused on fission, a process by which cells split symmetrically into two daughters. The yeast, Saccharomyces cerevisiae, is a model eukaryote which commonly undergoes an asymmetric division process called budding. The resulting mother and daughter cells have unequal sizes and the daughter cell does not inherit the replicative age of the mother. In this work, we develop and analyze an ABM to study the impact of budding cell division and nutrient limitation on yeast colony structure. We find that while budding division does not impact large-scale properties of the colony (such as shape and size), local spatial organization of cells with respect to spatial layout of mother-daughter cell pairs and connectivity of subcolonies is greatly impacted. In addition, we find that nutrient limitation further promotes local spatial organization of cells and changes global colony organization by driving variation in subcolony sizes. Moreover, resulting differences in spatial organization, coupled with differential growth rates from nutrient limitation, create distinct sectoring patterns within growing yeast colonies. Our findings offer novel insights into mechanisms driving experimentally observed sectored yeast colony phenotypes. Furthermore, our work illustrates the need to include relevant biophysical mechanisms when using ABMs to compare to experimental studies.
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16
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Epigenetic cell fate in Candida albicans is controlled by transcription factor condensates acting at super-enhancer-like elements. Nat Microbiol 2020; 5:1374-1389. [PMID: 32719507 PMCID: PMC7581547 DOI: 10.1038/s41564-020-0760-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 06/25/2020] [Indexed: 12/21/2022]
Abstract
Cell identity in eukaryotes is controlled by transcriptional regulatory networks (TRNs) that define cell type-specific gene expression. In the opportunistic fungal pathogen Candida albicans, TRNs regulate epigenetic switching between two alternative cell states, ‘white’ and ‘opaque’, that exhibit distinct host interactions. Here, we reveal that the transcription factors (TFs) regulating cell identity contain prion-like domains (PrLDs) that enable liquid-liquid demixing and the formation of phase-separated condensates. Multiple white-opaque TFs can co-assemble into complex condensates as observed on single DNA molecules. Moreover, heterotypic interactions between PrLDs supports the assembly of multifactorial condensates at a synthetic locus within live eukaryotic cells. Mutation of the Wor1 PrLD revealed that substitution of acidic residues abolished its ability to phase separate and to co-recruit other TFs in live cells, as well as its function in C. albicans cell fate determination. Together, these studies reveal that PrLDs support the assembly of TF complexes that control fungal cell identity and highlight parallels with the ‘super-enhancers’ that regulate mammalian cell fate.
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17
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Thomson GJ, Hernon C, Austriaco N, Shapiro RS, Belenky P, Bennett RJ. Metabolism-induced oxidative stress and DNA damage selectively trigger genome instability in polyploid fungal cells. EMBO J 2019; 38:e101597. [PMID: 31448850 PMCID: PMC6769381 DOI: 10.15252/embj.2019101597] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 06/30/2019] [Accepted: 08/01/2019] [Indexed: 01/04/2023] Open
Abstract
Understanding how cellular activities impact genome stability is critical to multiple biological processes including tumorigenesis and reproductive biology. The fungal pathogen Candida albicans displays striking genome dynamics during its parasexual cycle as tetraploid cells, but not diploid cells, exhibit genome instability and reduce their ploidy when grown on a glucose-rich "pre-sporulation" medium. Here, we reveal that C. albicans tetraploid cells are metabolically hyperactive on this medium with higher rates of fermentation and oxidative respiration relative to diploid cells. This heightened metabolism results in elevated levels of reactive oxygen species (ROS), activation of the ROS-responsive transcription factor Cap1, and the formation of DNA double-strand breaks. Genetic or chemical suppression of ROS levels suppresses each of these phenotypes and also protects against genome instability. These studies reveal how endogenous metabolic processes can generate sufficient ROS to trigger genome instability in polyploid C. albicans cells. We also discuss potential parallels with metabolism-induced instability in cancer cells and speculate that ROS-induced DNA damage could have facilitated ploidy cycling prior to a conventional meiosis in eukaryotes.
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Affiliation(s)
- Gregory J Thomson
- Molecular Microbiology and Immunology DepartmentBrown UniversityProvidenceRIUSA
| | - Claire Hernon
- Molecular Microbiology and Immunology DepartmentBrown UniversityProvidenceRIUSA
| | | | - Rebecca S Shapiro
- Department of Molecular and Cellular BiologyUniversity of GuelphGuelphONCanada
| | - Peter Belenky
- Molecular Microbiology and Immunology DepartmentBrown UniversityProvidenceRIUSA
| | - Richard J Bennett
- Molecular Microbiology and Immunology DepartmentBrown UniversityProvidenceRIUSA
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