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Joshi K, Luisi B, Wunderlin G, Saleh S, Lilly A, Okusolubo T, Farabaugh PJ. An evolutionarily conserved phosphoserine-arginine salt bridge in the interface between ribosomal proteins uS4 and uS5 regulates translational accuracy in Saccharomyces cerevisiae. Nucleic Acids Res 2024; 52:3989-4001. [PMID: 38340338 DOI: 10.1093/nar/gkae053] [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: 08/22/2023] [Revised: 01/08/2024] [Accepted: 02/08/2024] [Indexed: 02/12/2024] Open
Abstract
Protein-protein and protein-rRNA interactions at the interface between ribosomal proteins uS4 and uS5 are thought to maintain the accuracy of protein synthesis by increasing selection of cognate aminoacyl-tRNAs. Selection involves a major conformational change-domain closure-that stabilizes aminoacyl-tRNA in the ribosomal acceptor (A) site. This has been thought a constitutive function of the ribosome ensuring consistent accuracy. Recently, the Saccharomyces cerevisiae Ctk1 cyclin-dependent kinase was demonstrated to ensure translational accuracy and Ser238 of uS5 proposed as its target. Surprisingly, Ser238 is outside the uS4-uS5 interface and no obvious mechanism has been proposed to explain its role. We show that the true target of Ctk1 regulation is another uS5 residue, Ser176, which lies in the interface opposite to Arg57 of uS4. Based on site specific mutagenesis, we propose that phospho-Ser176 forms a salt bridge with Arg57, which should increase selectivity by strengthening the interface. Genetic data show that Ctk1 regulates accuracy indirectly; the data suggest that the kinase Ypk2 directly phosphorylates Ser176. A second kinase pathway involving TORC1 and Pkc1 can inhibit this effect. The level of accuracy appears to depend on competitive action of these two pathways to regulate the level of Ser176 phosphorylation.
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Affiliation(s)
- Kartikeya Joshi
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Brooke Luisi
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Grant Wunderlin
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Sima Saleh
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Anna Lilly
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Temiloluwa Okusolubo
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
| | - Philip J Farabaugh
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore 21250, USA
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2
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Puumala E, Fallah S, Robbins N, Cowen LE. Advancements and challenges in antifungal therapeutic development. Clin Microbiol Rev 2024; 37:e0014223. [PMID: 38294218 PMCID: PMC10938895 DOI: 10.1128/cmr.00142-23] [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] [Indexed: 02/01/2024] Open
Abstract
Over recent decades, the global burden of fungal disease has expanded dramatically. It is estimated that fungal disease kills approximately 1.5 million individuals annually; however, the true worldwide burden of fungal infection is thought to be higher due to existing gaps in diagnostics and clinical understanding of mycotic disease. The development of resistance to antifungals across diverse pathogenic fungal genera is an increasingly common and devastating phenomenon due to the dearth of available antifungal classes. These factors necessitate a coordinated response by researchers, clinicians, public health agencies, and the pharmaceutical industry to develop new antifungal strategies, as the burden of fungal disease continues to grow. This review provides a comprehensive overview of the new antifungal therapeutics currently in clinical trials, highlighting their spectra of activity and progress toward clinical implementation. We also profile up-and-coming intracellular proteins and pathways primed for the development of novel antifungals targeting their activity. Ultimately, we aim to emphasize the importance of increased investment into antifungal therapeutics in the current continually evolving landscape of infectious disease.
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Affiliation(s)
- Emily Puumala
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Sara Fallah
- 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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3
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Portes RG, Barreto TL, Kanemaru MYS, Ishida K, Bicas JL. Antifungal activity of cercosporamide produced by Phaeosphaeriaceae GV-1 against pathogenic fungi. Braz J Microbiol 2024; 55:383-389. [PMID: 38110707 PMCID: PMC10920561 DOI: 10.1007/s42770-023-01211-y] [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: 02/13/2023] [Accepted: 12/06/2023] [Indexed: 12/20/2023] Open
Abstract
Fungal infections affect millions of people worldwide, and the several cases are related to invasive infections, which is a problem mainly for immunocompromised people, such as transplant and cancer patients with high mortality and morbidity rates. In addition, the number of emerging and multidrug-resistant fungal species has increased in the last decade. The search for new antifungal compounds is necessary, due to the increase in cases of resistance and the toxicity of drugs used in fungal infection treatment. This work aimed to study the antifungal activity of cercosporamide produced by Phaeosphaeriaceae GV-1. Cercosporamide was tested against pathogenic fungi by determining the minimum inhibitory (MIC) and minimum fungicidal (MFC) concentrations, using the broth microdilution method. Cercosporamide showed antifungal activity in vitro against 13 of 16 strains of medical importance tested, with the most susceptible species being Candida tropicalis, with MIC and MFC of 15.6 μg/mL. Thus, cercosporamide might be considered a promising therapeutic antifungal agent.
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Affiliation(s)
- R G Portes
- Department of Food Science and Nutrition, School of Food Engineering, University of Campinas, Campinas, São Paulo, Brazil
| | - Thayná Lopes Barreto
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Michel Yudi Shinkai Kanemaru
- Department of Food Science and Nutrition, School of Food Engineering, University of Campinas, Campinas, São Paulo, Brazil
| | - Kelly Ishida
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Juliano Lemos Bicas
- Department of Food Science and Nutrition, School of Food Engineering, University of Campinas, Campinas, São Paulo, Brazil.
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4
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Liu R, Paguirigan JA, Hur JS, Kim W. Cercosporamide, a polyketide-derived fungal metabolite, serves as an antifungal agent against phytopathogenic fungi. MYCOSCIENCE 2024; 65:19-27. [PMID: 39239118 PMCID: PMC11371548 DOI: 10.47371/mycosci.2023.11.002] [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: 09/04/2023] [Revised: 11/20/2023] [Accepted: 11/22/2023] [Indexed: 09/07/2024]
Abstract
An endophytic fungus, Phoma sp. NG-25, produces a set of structurally related polyketides including cercosporamide, phomodione, and usnic acid, among which, cercosporamide has been reported to have strong antifungal and anticancer activities. In this study, Phoma sp. NG-25 was grown in seven growth media to determine the optimal culture condition conducive for cercosporamide production. Cercosporamide production peaked on the eighteenth day of incubation in beef peptone dextrose (BPD) broth media. The cercosporamide titer reached to an average of 77.5 µg/mL in BPD. Paper disk diffusion assay revealed that culture filtrate containing cercosporamide as a major constituent inhibited the growth of taxonomically diverse plant pathogens, including ascomycetous, basidiomycetous, and oomycete fungi. Cercosporamide exhibited strong antifungal activities against two pepper anthracnose pathogens, Colletotrichum gloeosporioides and C. scovillei with EC50 values of 3.8 and 7.0 µg/mL, respectively. This study suggests the potential application of cercosporamide as an effective antifungal agent in controlling anthracnose in pepper.
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Affiliation(s)
- Rundong Liu
- a Korean Lichen Research Institute, Sunchon National University
| | - Jaycee Augusto Paguirigan
- a Korean Lichen Research Institute, Sunchon National University
- b Department of Biological Sciences, College of Science, University of Santo Tomas
| | - Jae-Seoun Hur
- a Korean Lichen Research Institute, Sunchon National University
| | - Wonyong Kim
- a Korean Lichen Research Institute, Sunchon National University
- c Department of Applied Biology, College of Agriculture and Life Sciences, Chonnam National University
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5
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Vanzolini T, Magnani M. Old and new strategies in therapy and diagnosis against fungal infections. Appl Microbiol Biotechnol 2024; 108:147. [PMID: 38240822 PMCID: PMC10799149 DOI: 10.1007/s00253-023-12884-8] [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: 06/26/2023] [Revised: 12/05/2023] [Accepted: 12/05/2023] [Indexed: 01/22/2024]
Abstract
Fungal infections represent a serious global health threat. The new emerging pathogens and the spread of different forms of resistance are now hardly challenging the tools available in therapy and diagnostics. With the commonly used diagnoses, fungal identification is often slow and inaccurate, and, on the other hand, some drugs currently used as treatments are significantly affected by the decrease in susceptibility. Herein, the antifungal arsenal is critically summarized. Besides describing the old approaches and their mechanisms, advantages, and limitations, the focus is dedicated to innovative strategies which are designed, identified, and developed to take advantage of the discrepancies between fungal and host cells. Relevant pathways and their role in survival and virulence are discussed as their suitability as sources of antifungal targets. In a similar way, molecules with antifungal activity are reported as potential agents/precursors of the next generation of antimycotics. Particular attention was devoted to biotechnological entities, to their novelty and reliability, to drug repurposing and restoration, and to combinatorial applications yielding significant improvements in efficacy. KEY POINTS: • New antifungal agents and targets are needed to limit fungal morbidity and mortality. • Therapeutics and diagnostics suffer of delays in innovation and lack of targets. • Biologics, drug repurposing and combinations are the future of antifungal treatments.
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Affiliation(s)
- Tania Vanzolini
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029, Urbino, PU, Italy.
| | - Mauro Magnani
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029, Urbino, PU, Italy
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6
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Schusterbauer V, Fischer JE, Gangl S, Schenzle L, Rinnofner C, Geier M, Sailer C, Glieder A, Thallinger GG. Whole Genome Sequencing Analysis of Effects of CRISPR/Cas9 in Komagataella phaffii: A Budding Yeast in Distress. J Fungi (Basel) 2022; 8:jof8100992. [PMID: 36294556 PMCID: PMC9605565 DOI: 10.3390/jof8100992] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/12/2022] [Accepted: 09/15/2022] [Indexed: 11/16/2022] Open
Abstract
The industrially important non-conventional yeast Komagataella phaffii suffers from low rates of homologous recombination, making site specific genetic engineering tedious. Therefore, genome editing using CRISPR/Cas represents a simple and efficient alternative. To characterize on- and off-target mutations caused by CRISPR/Cas9 followed by non-homologous end joining repair, we chose a diverse set of CRISPR/Cas targets and conducted whole genome sequencing on 146 CRISPR/Cas9 engineered single colonies. We compared the outcomes of single target CRISPR transformations to double target experiments. Furthermore, we examined the extent of possible large deletions by targeting a large genomic region, which is likely to be non-essential. The analysis of on-target mutations showed an unexpectedly high number of large deletions and chromosomal rearrangements at the CRISPR target loci. We also observed an increase of on-target structural variants in double target experiments as compared to single target experiments. Targeting of two loci within a putatively non-essential region led to a truncation of chromosome 3 at the target locus in multiple cases, causing the deletion of 20 genes and several ribosomal DNA repeats. The identified de novo off-target mutations were rare and randomly distributed, with no apparent connection to unspecific CRISPR/Cas9 off-target binding sites.
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Affiliation(s)
- Veronika Schusterbauer
- bisy GmbH, Wuenschendorf 292, 8200 Hofstaetten, Austria
- Institute of Biomedical Imaging, Graz University of Technology, Stremayrgasse 16, 8010 Graz, Austria
| | | | - Sarah Gangl
- bisy GmbH, Wuenschendorf 292, 8200 Hofstaetten, Austria
| | - Lisa Schenzle
- bisy GmbH, Wuenschendorf 292, 8200 Hofstaetten, Austria
| | | | - Martina Geier
- bisy GmbH, Wuenschendorf 292, 8200 Hofstaetten, Austria
| | - Christian Sailer
- Institute of Biomedical Informatics, Graz University of Technology, Stremayrgasse 16, 8010 Graz, Austria
| | - Anton Glieder
- bisy GmbH, Wuenschendorf 292, 8200 Hofstaetten, Austria
| | - Gerhard G. Thallinger
- Institute of Biomedical Informatics, Graz University of Technology, Stremayrgasse 16, 8010 Graz, Austria
- OMICS Center Graz, BioTechMed Graz, Stiftingtalstraße 24, 8010 Graz, Austria
- Correspondence: ; Tel.: +43-316-873-5343
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7
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Lee Y, Liston SD, Lee D, Robbins N, Cowen LE. Functional analysis of the Candida albicans kinome reveals Hrr25 as a regulator of antifungal susceptibility. iScience 2022; 25:104432. [PMID: 35663022 PMCID: PMC9160768 DOI: 10.1016/j.isci.2022.104432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 05/05/2022] [Accepted: 05/13/2022] [Indexed: 12/14/2022] Open
Abstract
Candida albicans is a leading cause of death due to systemic fungal infections. Poor patient outcomes are attributable to the limited number of antifungal classes and the increasing prevalence of drug resistance. Protein kinases have emerged as rewarding targets in the development of drugs for diverse diseases, yet kinases remain untapped in the quest for new antifungals. Here, we performed a comprehensive analysis of the C. albicans kinome to identify genes for which loss-of-function confers hypersensitivity to the two most widely deployed antifungals, echinocandins and azoles. Through this analysis, we found a role for the casein kinase 1 (CK1) homologue Hrr25 in regulating tolerance to both antifungals as well as target-mediated echinocandin resistance. Follow-up investigations established that Hrr25 regulates these responses through its interaction with the SBF transcription factor. Thus, we provide insights into the circuitry governing cellular responses to antifungals and implicate Hrr25 as a key mediator of drug resistance. Screening Candida albicans kinase mutants reveals 47 regulators of antifungal tolerance Hrr25 is important for growth and cell wall/membrane stress tolerance Hrr25 enables target-mediated echinocandin resistance Hrr25 interacts with the SBF transcription factor complex
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Affiliation(s)
- Yunjin Lee
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Sean D Liston
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Dongyeob Lee
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
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8
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Sanz AB, García R, Pavón-Vergés M, Rodríguez-Peña JM, Arroyo J. Control of Gene Expression via the Yeast CWI Pathway. Int J Mol Sci 2022; 23:ijms23031791. [PMID: 35163713 PMCID: PMC8836261 DOI: 10.3390/ijms23031791] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/27/2022] [Accepted: 02/01/2022] [Indexed: 12/18/2022] Open
Abstract
Living cells exposed to stressful environmental situations can elicit cellular responses that guarantee maximal cell survival. Most of these responses are mediated by mitogen-activated protein kinase (MAPK) cascades, which are highly conserved from yeast to humans. Cell wall damage conditions in the yeast Saccharomyces cerevisiae elicit rescue mechanisms mainly associated with reprogramming specific transcriptional responses via the cell wall integrity (CWI) pathway. Regulation of gene expression by this pathway is coordinated by the MAPK Slt2/Mpk1, mainly via Rlm1 and, to a lesser extent, through SBF (Swi4/Swi6) transcription factors. In this review, we summarize the molecular mechanisms controlling gene expression upon cell wall stress and the role of chromatin structure in these processes. Some of these mechanisms are also discussed in the context of other stresses governed by different yeast MAPK pathways. Slt2 regulates both transcriptional initiation and elongation by interacting with chromatin at the promoter and coding regions of CWI-responsive genes but using different mechanisms for Rlm1- and SBF-dependent genes. Since MAPK pathways are very well conserved in eukaryotic cells and are essential for controlling cellular physiology, improving our knowledge regarding how they regulate gene expression could impact the future identification of novel targets for therapeutic intervention.
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9
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Dibenzofuran Derivatives Inspired from Cercosporamide as Dual Inhibitors of Pim and CLK1 Kinases. Molecules 2021; 26:molecules26216572. [PMID: 34770981 PMCID: PMC8587151 DOI: 10.3390/molecules26216572] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 11/17/2022] Open
Abstract
Pim kinases (proviral integration site for Moloney murine leukemia virus kinases) are overexpressed in various types of hematological malignancies and solid carcinomas, and promote cell proliferation and survival. Thus, Pim kinases are validated as targets for antitumor therapy. In this context, our combined efforts in natural product-inspired library generation and screening furnished very promising dibenzo[b,d]furan derivatives derived from cercosporamide. Among them, lead compound 44 was highlighted as a potent Pim-1/2 kinases inhibitor with an additional nanomolar IC50 value against CLK1 (cdc2-like kinases 1) and displayed a low micromolar anticancer potency towards the MV4-11 (AML) cell line, expressing high endogenous levels of Pim-1/2 kinases. The design, synthesis, structure-activity relationship, and docking studies are reported herein and supported by enzyme, cellular assays, and Galleria mellonella larvae testing for acute toxicity.
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10
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Synthesis of 4,7,9-Trihydroxy[1]benzofuro[3,2-d]pyrimidine-6-carboxamide: Evaluation of Cytotoxicity and Inhibition of Protein Kinase C (CaPkc1). J CHEM-NY 2021. [DOI: 10.1155/2021/7526347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The protein kinase Pkc1 of Candida albicans (CaPkc1), one of the key proteins involved in MAPK pathway, is described as a regulator of cell wall integrity during growth, morphogenesis, and response to cell wall stress. The (–)-cercosporamide is an antifungal natural product isolated from the phytopathogen fungus Cercosporidium henningsii. This phytoxin was found to inhibit selectively CaPkc1 and constitutes an interesting model for the design of novel antifungal molecules. In this research, 4,7,9-trihydroxy[1]benzofuro[3,2-d]pyrimidine-6-carboxamide (13) derived from (–)-cercosporamide was synthesized via a seven-step procedure by well-known reactions and evaluation of cytotoxicity and inhibition of CaPkc1. The bioassay showed CaPkc1 inhibitory activity 87% higher and cytotoxicity 100 times less than the reference, (–)-cercosporamide.
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11
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The Future of Antifungal Drug Therapy: Novel Compounds and Targets. Antimicrob Agents Chemother 2021; 65:AAC.01719-20. [PMID: 33229427 DOI: 10.1128/aac.01719-20] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Fungal infections are a universal problem and are routinely associated with high morbidity and mortality rates in immunocompromised patients. Existing therapies comprise five different classes of antifungal agents, four of which target the synthesis of ergosterol and cell wall glucans. However, the currently available antifungals have many limitations, including poor oral bioavailability, narrow therapeutic indices, and emerging drug resistance resulting from their use, thus making it essential to investigate the development of novel drugs which can overcome these limitations and add to the antifungal armamentarium. Advances have been made in antifungal drug discovery research and development over the past few years as evidenced by the presence of several new compounds currently in various stages of development. In the following minireview, we provide a comprehensive summary of compounds aimed at one or more novel molecular targets. We also briefly describe potential pathways relevant for fungal pathogenesis that can be considered for drug development in the near future.
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12
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Yousuf MS, Shiers SI, Sahn JJ, Price TJ. Pharmacological Manipulation of Translation as a Therapeutic Target for Chronic Pain. Pharmacol Rev 2021; 73:59-88. [PMID: 33203717 PMCID: PMC7736833 DOI: 10.1124/pharmrev.120.000030] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Dysfunction in regulation of mRNA translation is an increasingly recognized characteristic of many diseases and disorders, including cancer, diabetes, autoimmunity, neurodegeneration, and chronic pain. Approximately 50 million adults in the United States experience chronic pain. This economic burden is greater than annual costs associated with heart disease, cancer, and diabetes combined. Treatment options for chronic pain are inadequately efficacious and riddled with adverse side effects. There is thus an urgent unmet need for novel approaches to treating chronic pain. Sensitization of neurons along the nociceptive pathway causes chronic pain states driving symptoms that include spontaneous pain and mechanical and thermal hypersensitivity. More than a decade of preclinical research demonstrates that translational mechanisms regulate the changes in gene expression that are required for ongoing sensitization of nociceptive sensory neurons. This review will describe how key translation regulation signaling pathways, including the integrated stress response, mammalian target of rapamycin, AMP-activated protein kinase (AMPK), and mitogen-activated protein kinase-interacting kinases, impact the translation of different subsets of mRNAs. We then place these mechanisms of translation regulation in the context of chronic pain states, evaluate currently available therapies, and examine the potential for developing novel drugs. Considering the large body of evidence now published in this area, we propose that pharmacologically manipulating specific aspects of the translational machinery may reverse key neuronal phenotypic changes causing different chronic pain conditions. Therapeutics targeting these pathways could eventually be first-line drugs used to treat chronic pain disorders. SIGNIFICANCE STATEMENT: Translational mechanisms regulating protein synthesis underlie phenotypic changes in the sensory nervous system that drive chronic pain states. This review highlights regulatory mechanisms that control translation initiation and how to exploit them in treating persistent pain conditions. We explore the role of mammalian/mechanistic target of rapamycin and mitogen-activated protein kinase-interacting kinase inhibitors and AMPK activators in alleviating pain hypersensitivity. Modulation of eukaryotic initiation factor 2α phosphorylation is also discussed as a potential therapy. Targeting specific translation regulation mechanisms may reverse changes in neuronal hyperexcitability associated with painful conditions.
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Affiliation(s)
- Muhammad Saad Yousuf
- Center for Advanced Pain Studies, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas (M.S.Y., S.I.S., T.J.P.) and 4E Therapeutics Inc, Austin, Texas (J.J.S.)
| | - Stephanie I Shiers
- Center for Advanced Pain Studies, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas (M.S.Y., S.I.S., T.J.P.) and 4E Therapeutics Inc, Austin, Texas (J.J.S.)
| | - James J Sahn
- Center for Advanced Pain Studies, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas (M.S.Y., S.I.S., T.J.P.) and 4E Therapeutics Inc, Austin, Texas (J.J.S.)
| | - Theodore J Price
- Center for Advanced Pain Studies, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas (M.S.Y., S.I.S., T.J.P.) and 4E Therapeutics Inc, Austin, Texas (J.J.S.)
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13
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Shukla T, de la Peña JB, Perish JM, Ploski JE, Stumpf CR, Webster KR, Thorn CA, Campbell ZT. A Highly Selective MNK Inhibitor Rescues Deficits Associated with Fragile X Syndrome in Mice. Neurotherapeutics 2021; 18:624-639. [PMID: 33006091 PMCID: PMC8116363 DOI: 10.1007/s13311-020-00932-4] [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] [Accepted: 09/12/2020] [Indexed: 12/22/2022] Open
Abstract
Fragile X syndrome (FXS) is the most common inherited source of intellectual disability in humans. FXS is caused by mutations that trigger epigenetic silencing of the Fmr1 gene. Loss of Fmr1 results in increased activity of the mitogen-activated protein kinase (MAPK) pathway. An important downstream consequence is activation of the mitogen-activated protein kinase interacting protein kinase (MNK). MNK phosphorylates the mRNA cap-binding protein, eukaryotic initiation factor 4E (eIF4E). Excessive phosphorylation of eIF4E has been directly implicated in the cognitive and behavioral deficits associated with FXS. Pharmacological reduction of eIF4E phosphorylation is one potential strategy for FXS treatment. We demonstrate that systemic dosing of a highly specific, orally available MNK inhibitor, eFT508, attenuates numerous deficits associated with loss of Fmr1 in mice. eFT508 resolves a range of phenotypic abnormalities associated with FXS including macroorchidism, aberrant spinogenesis, and alterations in synaptic plasticity. Key behavioral deficits related to anxiety, social interaction, obsessive and repetitive activities, and object recognition are ameliorated by eFT508. Collectively, this work establishes eFT508 as a potential means to reverse deficits associated with FXS.
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Affiliation(s)
- Tarjani Shukla
- Department of Biological Sciences, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
- Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - June Bryan de la Peña
- Department of Biological Sciences, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
- Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - John M Perish
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Jonathan E Ploski
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, 75080, USA
| | | | | | - Catherine A Thorn
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Zachary T Campbell
- Department of Biological Sciences, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA.
- Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, 75080, USA.
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14
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Chen LC, Huang HL, HuangFu WC, Yen SC, Ngo ST, Wu YW, Lin TE, Sung TY, Lien ST, Tseng HJ, Pan SL, Huang WJ, Hsu KC. Biological Evaluation of Selected Flavonoids as Inhibitors of MNKs Targeting Acute Myeloid Leukemia. JOURNAL OF NATURAL PRODUCTS 2020; 83:2967-2975. [PMID: 33026809 DOI: 10.1021/acs.jnatprod.0c00516] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Excessive eIF4E phosphorylation by mitogen-activated protein kinase (MAPK)-interacting kinases 1 and 2 (MNK1 and MNK2; collectively, MNKs) has been associated with oncogenesis. The overexpression of eIF4E in acute myeloid leukemia (AML) is related to cancer cell growth and survival. Thus, the inhibition of MNKs and eIF4E phosphorylation are potential therapeutic strategies for AML. Herein, a structure-based virtual screening approach was performed to identify potential MNK inhibitors from natural products. Three flavonoids, apigenin, hispidulin, and luteolin, showed MNK2 inhibitory activity with IC50 values of 308, 252, and 579 nM, respectively. A structure-activity relationship analysis was performed to disclose the molecular interactions. Furthermore, luteolin exhibited substantial inhibitory efficacy against MNK1 (IC50 = 179 nM). Experimental results from cellular assays showed that hispidulin and luteolin inhibited the growth of MOLM-13 and MV4-11 AML cells by downregulating eIF4E phosphorylation and arresting the cell cycle at the G0/G1 phase. Therefore, hispidulin and luteolin showed promising results as lead compounds for the potential treatment for AML.
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Affiliation(s)
- Liang-Chieh Chen
- Warshel Institute for Computational Biology, The Chinese University of Hong Kong (Shenzhen), Shenzhen, Guangdong, People's Republic of China
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Han-Li Huang
- Ph.D. Program in Biotechnology Research and Development, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
- Biomedical Commercialization Center, Taipei Medical University, Taipei, Taiwan
| | - Wei-Chun HuangFu
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Ph.D. Program in Biotechnology Research and Development, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
- Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Shih-Chung Yen
- Warshel Institute for Computational Biology, The Chinese University of Hong Kong (Shenzhen), Shenzhen, Guangdong, People's Republic of China
| | - Sin-Ting Ngo
- Ph.D. Program in Biotechnology Research and Development, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
| | - Yi-Wen Wu
- Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Tony Eight Lin
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Tzu-Ying Sung
- Institute of Bioinformatics and Systems Biology, College of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan
| | - Ssu-Ting Lien
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Hui-Ju Tseng
- Ph.D. Program in Biotechnology Research and Development, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
| | - Shiow-Lin Pan
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Ph.D. Program in Biotechnology Research and Development, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
- Biomedical Commercialization Center, Taipei Medical University, Taipei, Taiwan
- Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Wei-Jan Huang
- Ph.D. Program in Biotechnology Research and Development, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
- Graduate Institute of Pharmacognosy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
- Ph.D. Program for the Clinical Drug Discovery from Botanical Herbs, College of Pharmacy, Taipei, Taiwan
- School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
| | - Kai-Cheng Hsu
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Ph.D. Program in Biotechnology Research and Development, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
- Biomedical Commercialization Center, Taipei Medical University, Taipei, Taiwan
- Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
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15
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Bunyapaiboonsri T, Yoiprommarat S, Suntivich R, Preedanon S, Komwijit S, Teerawatananond T, Sakayaroj J. A cyclic lipodepsipeptide, a spirolactone, and a chromanone from the marine fungus Verruculina enalia (Kohlm.) Kohlm. & Volkm.-Kohlm. BCC 22226. Tetrahedron 2020. [DOI: 10.1016/j.tet.2020.131497] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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16
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Hoeksma J, van der Zon GCM, Ten Dijke P, den Hertog J. Cercosporamide inhibits bone morphogenetic protein receptor type I kinase activity in zebrafish. Dis Model Mech 2020; 13:dmm045971. [PMID: 32820031 PMCID: PMC7522027 DOI: 10.1242/dmm.045971] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 08/10/2020] [Indexed: 02/06/2023] Open
Abstract
Zebrafish models are well-established tools for investigating the underlying mechanisms of diseases. Here, we identified cercosporamide, a metabolite from the fungus Ascochyta aquiliqiae, as a potent bone morphogenetic protein receptor (BMPR) type I kinase inhibitor through a zebrafish embryo phenotypic screen. The developmental defects in zebrafish, including lack of the ventral fin, induced by cercosporamide were strikingly similar to the phenotypes caused by renowned small-molecule BMPR type I kinase inhibitors and inactivating mutations in zebrafish BMPRs. In mammalian cell-based assays, cercosporamide blocked BMP/SMAD-dependent transcriptional reporter activity and BMP-induced SMAD1/5-phosphorylation. Biochemical assays with a panel of purified recombinant kinases demonstrated that cercosporamide directly inhibited kinase activity of type I BMPRs [also called activin receptor-like kinases (ALKs)]. In mammalian cells, cercosporamide selectively inhibited constitutively active BMPR type I-induced SMAD1/5 phosphorylation. Importantly, cercosporamide rescued the developmental defects caused by constitutively active Alk2 in zebrafish embryos. We believe that cercosporamide could be the first of a new class of molecules with potential to be developed further for clinical use against diseases that are causally linked to overactivation of BMPR signaling, including fibrodysplasia ossificans progressiva and diffuse intrinsic pontine glioma.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Jelmer Hoeksma
- Hubrecht Institute - KNAW and University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands
| | - Gerard C M van der Zon
- Department of Cell and Chemical Biology, Leiden University Medical Center, 2333 ZC Leiden, The Netherlands
- Oncode Institute, Leiden University Medical Center, 2333 ZC Leiden, The Netherlands
| | - Peter Ten Dijke
- Department of Cell and Chemical Biology, Leiden University Medical Center, 2333 ZC Leiden, The Netherlands
- Oncode Institute, Leiden University Medical Center, 2333 ZC Leiden, The Netherlands
| | - Jeroen den Hertog
- Hubrecht Institute - KNAW and University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands
- Institute Biology Leiden, Leiden University, 2333 BE Leiden, The Netherlands
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17
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LeBlanc EV, Polvi EJ, Veri AO, Privé GG, Cowen LE. Structure-guided approaches to targeting stress responses in human fungal pathogens. J Biol Chem 2020; 295:14458-14472. [PMID: 32796038 DOI: 10.1074/jbc.rev120.013731] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 08/11/2020] [Indexed: 11/06/2022] Open
Abstract
Fungi inhabit extraordinarily diverse ecological niches, including the human body. Invasive fungal infections have a devastating impact on human health worldwide, killing ∼1.5 million individuals annually. The majority of these deaths are attributable to species of Candida, Cryptococcus, and Aspergillus Treating fungal infections is challenging, in part due to the emergence of resistance to our limited arsenal of antifungal agents, necessitating the development of novel therapeutic options. Whereas conventional antifungal strategies target proteins or cellular components essential for fungal growth, an attractive alternative strategy involves targeting proteins that regulate fungal virulence or antifungal drug resistance, such as regulators of fungal stress responses. Stress response networks enable fungi to adapt, grow, and cause disease in humans and include regulators that are highly conserved across eukaryotes as well as those that are fungal-specific. This review highlights recent developments in elucidating crystal structures of fungal stress response regulators and emphasizes how this knowledge can guide the design of fungal-selective inhibitors. We focus on the progress that has been made with highly conserved regulators, including the molecular chaperone Hsp90, the protein phosphatase calcineurin, and the small GTPase Ras1, as well as with divergent stress response regulators, including the cell wall kinase Yck2 and trehalose synthases. Exploring structures of these important fungal stress regulators will accelerate the design of selective antifungals that can be deployed to combat life-threatening fungal diseases.
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Affiliation(s)
- Emmanuelle V LeBlanc
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Elizabeth J Polvi
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Amanda O Veri
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Gilbert G Privé
- Departments of Medical Biophysics and Biochemistry, University of Toronto, Toronto, Ontario, Canada.,Princess Margaret Cancer Centre, Toronto, Ontario, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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18
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Tripathi SK, Feng Q, Liu L, Levin DE, Roy KK, Doerksen RJ, Baerson SR, Shi X, Pan X, Xu WH, Li XC, Clark AM, Agarwal AK. Puupehenone, a Marine-Sponge-Derived Sesquiterpene Quinone, Potentiates the Antifungal Drug Caspofungin by Disrupting Hsp90 Activity and the Cell Wall Integrity Pathway. mSphere 2020; 5:e00818-19. [PMID: 31915228 PMCID: PMC6952202 DOI: 10.1128/msphere.00818-19] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 12/04/2019] [Indexed: 02/02/2023] Open
Abstract
The cell wall-targeting echinocandin antifungals, although potent and well tolerated, are inadequate in treating fungal infections due to their narrow spectrum of activity and their propensity to induce pathogen resistance. A promising strategy to overcome these drawbacks is to combine echinocandins with a molecule that improves their activity and also disrupts drug adaptation pathways. In this study, we show that puupehenone (PUUP), a marine-sponge-derived sesquiterpene quinone, potentiates the echinocandin drug caspofungin (CAS) in CAS-resistant fungal pathogens. We have conducted RNA sequencing (RNA-seq) analysis, followed by genetic and molecular studies, to elucidate PUUP's CAS-potentiating mechanism. We found that the combination of CAS and PUUP blocked the induction of CAS-responding genes required for the adaptation to cell wall stress through the cell wall integrity (CWI) pathway. Further analysis showed that PUUP inhibited the activation of Slt2 (Mpk1), the terminal mitogen-activated protein (MAP) kinase in this pathway. We also found that PUUP induced heat shock response genes and inhibited the activity of heat shock protein 90 (Hsp90). Molecular docking studies predicted that PUUP occupies a binding site on Hsp90 required for the interaction between Hsp90 and its cochaperone Cdc37. Thus, we show that PUUP potentiates CAS activity by a previously undescribed mechanism which involves a disruption of Hsp90 activity and the CWI pathway. Given the requirement of the Hsp90-Cdc37 complex in Slt2 activation, we suggest that inhibitors of this complex would disrupt the CWI pathway and synergize with echinocandins. Therefore, the identification of PUUP's CAS-potentiating mechanism has important implications in the development of new antifungal combination therapies.IMPORTANCE Fungal infections cause more fatalities worldwide each year than malaria or tuberculosis. Currently available antifungal drugs have various limitations, including host toxicity, narrow spectrum of activity, and pathogen resistance. Combining these drugs with small molecules that can overcome these limitations is a useful strategy for extending their clinical use. We have investigated the molecular mechanism by which a marine-derived compound potentiates the activity of the antifungal echinocandin caspofungin. Our findings revealed a mechanism, different from previously reported caspofungin potentiators, in which potentiation is achieved by the disruption of Hsp90 activity and signaling through the cell wall integrity pathway, processes that play important roles in the adaptation to caspofungin in fungal pathogens. Given the importance of stress adaptation in the development of echinocandin resistance, this work will serve as a starting point in the development of new combination therapies that will likely be more effective and less prone to pathogen resistance.
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Affiliation(s)
- Siddharth K Tripathi
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
| | - Qin Feng
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
| | - Li Liu
- Department of Molecular and Cell Biology, Boston University Henry M. Goldman School of Dental Medicine, Boston, Massachusetts, USA
| | - David E Levin
- Department of Molecular and Cell Biology, Boston University Henry M. Goldman School of Dental Medicine, Boston, Massachusetts, USA
| | - Kuldeep K Roy
- Division of Medicinal Chemistry, Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
| | - Robert J Doerksen
- Division of Medicinal Chemistry, Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
| | - Scott R Baerson
- Natural Products Utilization Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Oxford, Mississippi, USA
| | - Xiaomin Shi
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Xuewen Pan
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Wen-Hui Xu
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
| | - Xing-Cong Li
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
- Division of Pharmacognosy, Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
| | - Alice M Clark
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
- Division of Pharmacognosy, Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
| | - Ameeta K Agarwal
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
- Division of Pharmacology, Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
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19
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Caplan T, Lorente-Macías Á, Stogios PJ, Evdokimova E, Hyde S, Wellington MA, Liston S, Iyer KR, Puumala E, Shekhar-Guturja T, Robbins N, Savchenko A, Krysan DJ, Whitesell L, Zuercher WJ, Cowen LE. Overcoming Fungal Echinocandin Resistance through Inhibition of the Non-essential Stress Kinase Yck2. Cell Chem Biol 2020; 27:269-282.e5. [PMID: 31924499 DOI: 10.1016/j.chembiol.2019.12.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 11/20/2019] [Accepted: 12/17/2019] [Indexed: 01/12/2023]
Abstract
New strategies are urgently needed to counter the threat to human health posed by drug-resistant fungi. To explore an as-yet unexploited target space for antifungals, we screened a library of protein kinase inhibitors for the ability to reverse resistance of the most common human fungal pathogen, Candida albicans, to caspofungin, a widely used antifungal. This screen identified multiple 2,3-aryl-pyrazolopyridine scaffold compounds capable of restoring caspofungin sensitivity. Using chemical genomic, biochemical, and structural approaches, we established the target for our most potent compound as Yck2, a casein kinase 1 family member. Combination of this compound with caspofungin eradicated drug-resistant C. albicans infection while sparing co-cultured human cells. In mice, genetic depletion of YCK2 caused an ∼3-log10 decline in fungal burden in a model of systemic caspofungin-resistant C. albicans infection. Structural insights and our tool compound's profile in culture support targeting the Yck2 kinase function as a broadly active antifungal strategy.
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Affiliation(s)
- Tavia Caplan
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Álvaro Lorente-Macías
- Structural Genomics Consortium, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Medicinal & Organic Chemistry and Excellence Research Unit of "Chemistry Applied to Biomedicine and the Environment", Faculty of Pharmacy, University of Granada, Campus de Cartuja s/n, 18071 Granada, Spain
| | - Peter J Stogios
- Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5G 1M1, Canada; Center for Structural Genomics of Infectious Diseases (CSGID), Toronto, ON, M5G 1M1, Canada
| | - Elena Evdokimova
- Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5G 1M1, Canada; Center for Structural Genomics of Infectious Diseases (CSGID), Toronto, ON, M5G 1M1, Canada
| | - Sabrina Hyde
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Melanie A Wellington
- Departments of Pediatrics and Microbiology/Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Sean Liston
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Kali R Iyer
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Emily Puumala
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Tanvi Shekhar-Guturja
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Alexei Savchenko
- Center for Structural Genomics of Infectious Diseases (CSGID), Toronto, ON, M5G 1M1, Canada; Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Damian J Krysan
- Departments of Pediatrics and Microbiology/Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Luke Whitesell
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - William J Zuercher
- Structural Genomics Consortium, Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada.
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20
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Wang L, Shen J, Xu L, Gao J, Zhang C, Wang Y, Chen F. A metabolite of endophytic fungus Cadophora orchidicola from Kalimeris indica serves as a potential fungicide and TLR4 agonist. J Appl Microbiol 2019; 126:1383-1390. [PMID: 30811736 DOI: 10.1111/jam.14239] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/18/2019] [Accepted: 02/21/2019] [Indexed: 01/29/2023]
Abstract
AIM To investigate the bioactive metabolite of endophytic fungus from Kalimeris indica. METHODS AND RESULTS A strain ZJLQ336 was separated from the leaves of K. indica. It was identified as Cadophora orchidicola based on the phylogenetic analysis of ITS-rDNA sequences. From the fermentation broth a metabolite cercosporamide (compound 1) was isolated, and its structure was determined by spectroscopic analysis. Additionally, this compound was subjected to bioactivity assays, including antifungal activity against seven plant pathogenic fungi, as well as its potential immunoregulatory effects on HEK-BLUE™-hTLR4 cells, splenocytes and macrophages. The results showed that cercosporamide had strong growth inhibition against five common plant pathogenic fungi, including Pestalotia diospyri, Botrytis cinerea, Fusarium oxysporum, Sclerotium rolfsii and Penicillum digitatum with EC50 values of 5·29 × 10-3 , 0·61, 0·93, 2·89 and 6·7 μg ml-1 respectively. Among which S. rolfsii was one of the main pathogens in K. indica. Moreover, cercosporamide not only significantly stimulated TLR4 activation, splenocyte proliferation and production of cytokines, IFN-γ and TNF-α, but also up-regulated the production of TNF-α and NO in RAW264.7 macrophages clearly. CONCLUSIONS This is the first report of endophytic C. orchidicola from K. indica and its metabolite cercosporamide. The results of pharmacological tests highlight the potential fungicide and TLR4 agonist of cercosporamide. SIGNIFICANCE AND IMPACT OF THE STUDY This study indicates endophytic fungi are good resources for natural bioactive metabolites. It also suggests that cercosporamide is a potential fungicide and TLR4 agonist.
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Affiliation(s)
- L Wang
- Department of Pharmaceutical Science, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - J Shen
- Department of Pharmaceutical Science, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - L Xu
- Department of Pharmaceutical Science, School of Medicine, Hangzhou Normal University, Hangzhou, China.,Ningbo Women and Children's Hospital, Ningbo, China
| | - J Gao
- Department of Pharmaceutical Science, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - C Zhang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Y Wang
- Zhejiang Chinese Medical University, Hangzhou, China
| | - F Chen
- School of Basic Medical Sciences & Forensic Medicine, Hangzhou Medical College, Hangzhou, China
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21
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Benzofuro[3,2-d]pyrimidines inspired from cercosporamide CaPkc1 inhibitor: Synthesis and evaluation of fluconazole susceptibility restoration. Bioorg Med Chem Lett 2018; 28:2250-2255. [DOI: 10.1016/j.bmcl.2018.05.044] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/20/2018] [Accepted: 05/23/2018] [Indexed: 01/05/2023]
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22
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González-Menéndez V, Crespo G, de Pedro N, Diaz C, Martín J, Serrano R, Mackenzie TA, Justicia C, González-Tejero MR, Casares M, Vicente F, Reyes F, Tormo JR, Genilloud O. Fungal endophytes from arid areas of Andalusia: high potential sources for antifungal and antitumoral agents. Sci Rep 2018; 8:9729. [PMID: 29950656 PMCID: PMC6021435 DOI: 10.1038/s41598-018-28192-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 06/19/2018] [Indexed: 01/05/2023] Open
Abstract
Native plant communities from arid areas present distinctive characteristics to survive in extreme conditions. The large number of poorly studied endemic plants represents a unique potential source for the discovery of novel fungal symbionts as well as host-specific endophytes not yet described. The addition of adsorptive polymeric resins in fungal fermentations has been seen to promote the production of new secondary metabolites and is a tool used consistently to generate new compounds with potential biological activities. A total of 349 fungal strains isolated from 63 selected plant species from arid ecosystems located in the southeast of the Iberian Peninsula, were characterized morphologically as well as based on their ITS/28S ribosomal gene sequences. The fungal community isolated was distributed among 19 orders including Basidiomycetes and Ascomycetes, being Pleosporales the most abundant order. In total, 107 different genera were identified being Neocamarosporium the genus most frequently isolated from these plants, followed by Preussia and Alternaria. Strains were grown in four different media in presence and absence of selected resins to promote chemical diversity generation of new secondary metabolites. Fermentation extracts were evaluated, looking for new antifungal activities against plant and human fungal pathogens, as well as, cytotoxic activities against the human liver cancer cell line HepG2. From the 349 isolates tested, 126 (36%) exhibited significant bioactivities including 58 strains with exclusive antifungal properties and 33 strains with exclusive activity against the HepG2 hepatocellular carcinoma cell line. After LCMS analysis, 68 known bioactive secondary metabolites could be identified as produced by 96 strains, and 12 likely unknown compounds were found in a subset of 14 fungal endophytes. The chemical profiles of the differential expression of induced activities were compared. As proof of concept, ten active secondary metabolites only produced in the presence of resins were purified and identified. The structures of three of these compounds were new and herein are elucidated.
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Affiliation(s)
| | - Gloria Crespo
- Fundación MEDINA, Avda. del conocimiento 34, 18016, Granada, Spain
| | - Nuria de Pedro
- Fundación MEDINA, Avda. del conocimiento 34, 18016, Granada, Spain
| | - Caridad Diaz
- Fundación MEDINA, Avda. del conocimiento 34, 18016, Granada, Spain
| | - Jesús Martín
- Fundación MEDINA, Avda. del conocimiento 34, 18016, Granada, Spain
| | - Rachel Serrano
- Fundación MEDINA, Avda. del conocimiento 34, 18016, Granada, Spain
| | | | - Carlos Justicia
- Fundación MEDINA, Avda. del conocimiento 34, 18016, Granada, Spain
| | - M Reyes González-Tejero
- Departamento de Botánica, Facultad de Farmacia, Universidad de Granada, C/ Prof. Clavera, s/n, 18011, Granada, Spain
| | - M Casares
- Departamento de Botánica, Facultad de Farmacia, Universidad de Granada, C/ Prof. Clavera, s/n, 18011, Granada, Spain
| | | | - Fernando Reyes
- Fundación MEDINA, Avda. del conocimiento 34, 18016, Granada, Spain
| | - José R Tormo
- Fundación MEDINA, Avda. del conocimiento 34, 18016, Granada, Spain
| | - Olga Genilloud
- Fundación MEDINA, Avda. del conocimiento 34, 18016, Granada, Spain
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23
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Manfiolli AO, Dos Reis TF, de Assis LJ, de Castro PA, Silva LP, Hori JI, Walker LA, Munro CA, Rajendran R, Ramage G, Goldman GH. Mitogen activated protein kinases (MAPK) and protein phosphatases are involved in Aspergillus fumigatus adhesion and biofilm formation. Cell Surf 2018; 1:43-56. [PMID: 32743127 PMCID: PMC7389341 DOI: 10.1016/j.tcsw.2018.03.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/08/2018] [Accepted: 03/14/2018] [Indexed: 12/28/2022] Open
Abstract
The main characteristic of biofilm formation is extracellular matrix (ECM) production. The cells within the biofilm are surrounded by ECM which provides structural integrity and protection. During an infection, this protection is mainly against cells of the immune system and antifungal drugs. A. fumigatus forms biofilms during static growth on a solid substratum and in chronic aspergillosis infections. It is important to understand how, and which, A. fumigatus signal transduction pathways are important for the adhesion and biofilm formation in a host during infection. Here we investigated the role of MAP kinases and protein phosphatases in biofilm formation. The loss of the MAP kinases MpkA, MpkC and SakA had an impact on the cell surface and the ECM during biofilm formation and reduced the adherence of A. fumigatus to polystyrene and fibronectin-coated plates. The phosphatase null mutants ΔsitA and ΔptcB, involved in regulation of MpkA and SakA phosphorylation, influenced cell wall carbohydrate exposure. Moreover, we characterized the A. fumigatus protein phosphatase PphA. The ΔpphA strain was more sensitive to cell wall-damaging agents, had increased β-(1,3)-glucan and reduced chitin, decreased conidia phagocytosis by Dictyostelium discoideum and reduced adhesion and biofilm formation. Finally, ΔpphA strain was avirulent in a murine model of invasive pulmonary aspergillosis and increased the released of tumor necrosis factor alpha (TNF-α) from bone marrow derived macrophages (BMDMs). These results show that MAP kinases and phosphatases play an important role in signaling pathways that regulate the composition of the cell wall, extracellular matrix production as well as adhesion and biofilm formation in A. fumigatus.
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Affiliation(s)
- Adriana Oliveira Manfiolli
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Thaila Fernanda Dos Reis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Leandro José de Assis
- 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
| | - Juliana I Hori
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Louise A Walker
- School of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Carol A Munro
- School of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Ranjith Rajendran
- Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, College of Medical, Veterinary and Life Sciences, The University of Glasgow, 378 Sauchiehall Street, Glasgow G2 3JZ, UK
| | - Gordon Ramage
- Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, College of Medical, Veterinary and Life Sciences, The University of Glasgow, 378 Sauchiehall Street, Glasgow G2 3JZ, UK
| | - Gustavo H Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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Ma Y, Liang S, Zhang Y, Yang D, Wang R. Development of anti-fungal pesticides from protein kinase inhibitor-based anticancer agents. Eur J Med Chem 2018; 148:349-358. [DOI: 10.1016/j.ejmech.2018.02.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 02/11/2018] [Accepted: 02/12/2018] [Indexed: 11/25/2022]
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25
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Gong Y, Li T, Yu C, Sun S. Candida albicans Heat Shock Proteins and Hsps-Associated Signaling Pathways as Potential Antifungal Targets. Front Cell Infect Microbiol 2017; 7:520. [PMID: 29312897 PMCID: PMC5742142 DOI: 10.3389/fcimb.2017.00520] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 12/07/2017] [Indexed: 11/28/2022] Open
Abstract
In recent decades, the incidence of invasive fungal infections has increased notably. Candida albicans (C. albicans), a common opportunistic fungal pathogen that dwells on human mucosal surfaces, can cause fungal infections, especially in immunocompromised and high-risk surgical patients. In addition, the wide use of antifungal agents has likely contributed to resistance of C. albicans to traditional antifungal drugs, increasing the difficulty of treatment. Thus, it is urgent to identify novel antifungal drugs to cope with C. albicans infections. Heat shock proteins (Hsps) exist in most organisms and are expressed in response to thermal stress. In C. albicans, Hsps control basic physiological activities or virulence via interaction with a variety of diverse regulators of cellular signaling pathways. Moreover, it has been demonstrated that Hsps confer drug resistance to C. albicans. Many studies have shown that disrupting the normal functions of C. albicans Hsps inhibits fungal growth or reverses the tolerance of C. albicans to traditional antifungal drugs. Here, we review known functions of the diverse Hsp family, Hsp-associated intracellular signaling pathways and potential antifungal targets based on these pathways in C. albicans. We hope this review will aid in revealing potential new roles of C. albicans Hsps in addition to canonical heat stress adaptions and provide more insight into identifying potential novel antifungal targets.
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Affiliation(s)
- Ying Gong
- School of Pharmaceutical Sciences, Shandong University, Jinan, China
| | - Tao Li
- Intensive Care Unit, Qianfoshan Hospital Affiliated to Shandong University, Jinan, China
| | - Cuixiang Yu
- Respiration Medicine, Qianfoshan Hospital Affiliated to Shandong University, Jinan, China
| | - Shujuan Sun
- Department of Pharmacy, Qianfoshan Hospital Affiliated to Shandong University, Jinan, China
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Heinisch JJ, Rodicio R. Protein kinase C in fungi—more than just cell wall integrity. FEMS Microbiol Rev 2017; 42:4562651. [DOI: 10.1093/femsre/fux051] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 10/19/2017] [Indexed: 11/13/2022] Open
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27
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Wang LW, Wang JL, Chen J, Chen JJ, Shen JW, Feng XX, Kubicek CP, Lin FC, Zhang CL, Chen FY. A Novel Derivative of (-)mycousnine Produced by the Endophytic Fungus Mycosphaerella nawae, Exhibits High and Selective Immunosuppressive Activity on T Cells. Front Microbiol 2017; 8:1251. [PMID: 28725220 PMCID: PMC5496962 DOI: 10.3389/fmicb.2017.01251] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 06/21/2017] [Indexed: 11/15/2022] Open
Abstract
An endophytic fungus, Mycosphaerella nawae ZJLQ129, was isolated from the leaves of the traditional Chinese medicine Smilax china. From the fermentation broth and mycelium, a dibenzofurane compound (-)mycousnine (1) was isolated. Chemical modification of it to the amide derivative (-)mycousnine enamine (2), which is new to science, was found to have high and selective immunosuppressive activity: similar to cyclosporin A, (-)mycousnine enamine (2) selectively inhibited T cell proliferation, suppressed the expression of the surface activation antigens CD25 and CD69 and the formation and expression of the cytokines interleukin-2 as well as interferon γ in activated T cells, but did not show any effect on the proliferation of B cells and cancer cells (PANC-1 and A549) and the activation of macrophages. Furthermore, the cytotoxicity of (-)mycousnine enamine was lower than that of cyclosporin A, and its therapeutic index (TC50/EC50) was 4,463.5, which is five-fold higher than that of cyclosporin A. We conclude that (-)mycousnine enamine (2), the semi-synthestic product prepared from the native product (-)mycousnine (1) of the endophyte M. nawae is a novel effective immunosuppressant showing low toxicity and high selectivity.
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Affiliation(s)
- Li-Wei Wang
- Department of Pharmaceutical Science, College of Medical Science, Hangzhou Normal UniversityHangzhou, China
| | - Jin-Liang Wang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang UniversityHangzhou, China
| | - Jing Chen
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang UniversityHangzhou, China
| | - Jia-Jie Chen
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang UniversityHangzhou, China
| | - Jia-Wei Shen
- Department of Pharmaceutical Science, College of Medical Science, Hangzhou Normal UniversityHangzhou, China
| | - Xiao-Xiao Feng
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang UniversityHangzhou, China
| | - Christian P Kubicek
- Institute of Chemical Engineering, Vienna University of TechnologyVienna, Austria
| | - Fu-Cheng Lin
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang UniversityHangzhou, China
| | - Chu-Long Zhang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang UniversityHangzhou, China
| | - Feng-Yang Chen
- Institute of Materia Medica, Zhejiang Academy of Medical SciencesHangzhou, China.,Department of Basic Medical Science, Hangzhou Medical CollegeHangzhou, China
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O'Meara TR, Robbins N, Cowen LE. The Hsp90 Chaperone Network Modulates Candida Virulence Traits. Trends Microbiol 2017; 25:809-819. [PMID: 28549824 DOI: 10.1016/j.tim.2017.05.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 04/28/2017] [Accepted: 05/02/2017] [Indexed: 11/30/2022]
Abstract
Hsp90 is a conserved molecular chaperone that facilitates the folding and function of client proteins. Hsp90 function is dynamically regulated by interactions with co-chaperones and by post-translational modifications. In the fungal pathogen Candida albicans, Hsp90 enables drug resistance and virulence by stabilizing diverse signal transducers. Here, we review studies that have unveiled regulators of Hsp90 function, as well as downstream effectors that govern the key virulence traits of morphogenesis and drug resistance. We highlight recent work mapping the Hsp90 genetic network in C. albicans under diverse environmental conditions, and how these interactions provide insight into circuitry important for drug resistance, morphogenesis, and virulence. Ultimately, elucidating the Hsp90 chaperone network will aid in the development of therapeutics to treat fungal disease.
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Affiliation(s)
- Teresa R O'Meara
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5G 1M1, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5G 1M1, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5G 1M1, Canada.
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29
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Staurosporine Induces Filamentation in the Human Fungal Pathogen Candida albicans via Signaling through Cyr1 and Protein Kinase A. mSphere 2017; 2:mSphere00056-17. [PMID: 28261668 PMCID: PMC5332603 DOI: 10.1128/msphere.00056-17] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 02/09/2017] [Indexed: 01/10/2023] Open
Abstract
The impact of fungal pathogens on human health is devastating. One of the most pervasive fungal pathogens is Candida albicans, which kills ~40% of people suffering from bloodstream infections. Treatment of these infections is extremely difficult, as fungi are closely related to humans, and there are limited drugs that kill the fungus without host toxicity. The capacity of C. albicans to transition between yeast and filamentous forms is a key virulence trait. Thus, understanding the genetic pathways that regulate morphogenesis could provide novel therapeutic targets to treat C. albicans infections. Here, we establish the small molecule staurosporine as an inducer of filamentous growth. We unveil distinct regulatory circuitry required for staurosporine-induced filamentation that appears to be unique to this filament-inducing cue. Thus, this work highlights the fact that small molecules, such as staurosporine, can improve our understanding of the pathways required for key virulence programs, which may lead to the development of novel therapeutics. Protein kinases are key regulators of signal transduction pathways that participate in diverse cellular processes. In fungal pathogens, kinases regulate signaling pathways that govern drug resistance, stress adaptation, and pathogenesis. The impact of kinases on the fungal regulatory circuitry has recently garnered considerable attention in the opportunistic fungal pathogen Candida albicans, which is a leading cause of human morbidity and mortality. Complex regulatory circuitry governs the C. albicans morphogenetic transition between yeast and filamentous growth, which is a key virulence trait. Here, we report that staurosporine, a promiscuous kinase inhibitor that abrogates fungal drug resistance, also influences C. albicans morphogenesis by inducing filamentation in the absence of any other inducing cue. We further establish that staurosporine exerts its effect via the adenylyl cyclase Cyr1 and the cyclic AMP (cAMP)-dependent protein kinase A (PKA). Strikingly, filamentation induced by staurosporine does not require the known upstream regulators of Cyr1, Ras1 or Pkc1, or effectors downstream of PKA, including Efg1. We further demonstrate that Cyr1 is capable of activating PKA to enable filamentation in response to staurosporine through a mechanism that does not require degradation of the transcriptional repressor Nrg1. We establish that staurosporine-induced filamentation is accompanied by a defect in septin ring formation, implicating cell cycle kinases as potential staurosporine targets underpinning this cellular response. Thus, we establish staurosporine as a chemical probe to elucidate the architecture of cellular signaling governing fungal morphogenesis and highlight the existence of novel circuitry through which the Cyr1 and PKA govern a key virulence trait. IMPORTANCE The impact of fungal pathogens on human health is devastating. One of the most pervasive fungal pathogens is Candida albicans, which kills ~40% of people suffering from bloodstream infections. Treatment of these infections is extremely difficult, as fungi are closely related to humans, and there are limited drugs that kill the fungus without host toxicity. The capacity of C. albicans to transition between yeast and filamentous forms is a key virulence trait. Thus, understanding the genetic pathways that regulate morphogenesis could provide novel therapeutic targets to treat C. albicans infections. Here, we establish the small molecule staurosporine as an inducer of filamentous growth. We unveil distinct regulatory circuitry required for staurosporine-induced filamentation that appears to be unique to this filament-inducing cue. Thus, this work highlights the fact that small molecules, such as staurosporine, can improve our understanding of the pathways required for key virulence programs, which may lead to the development of novel therapeutics.
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30
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Wang SN, Bai O. [The advances of clinical and molecular prognostic factors of diffuse large B-cell lymphoma]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2017; 37:538-41. [PMID: 27431086 PMCID: PMC7348340 DOI: 10.3760/cma.j.issn.0253-2727.2016.06.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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31
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Functional Genomic Analysis of Candida albicans Adherence Reveals a Key Role for the Arp2/3 Complex in Cell Wall Remodelling and Biofilm Formation. PLoS Genet 2016; 12:e1006452. [PMID: 27870871 PMCID: PMC5147769 DOI: 10.1371/journal.pgen.1006452] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 10/31/2016] [Indexed: 12/28/2022] Open
Abstract
Fungal biofilms are complex, structured communities that can form on surfaces such as catheters and other indwelling medical devices. Biofilms are of particular concern with Candida albicans, one of the leading opportunistic fungal pathogens of humans. C. albicans biofilms include yeast and filamentous cells that are surrounded by an extracellular matrix, and they are intrinsically resistant to antifungal drugs such that resolving biofilm infections often requires surgery to remove the contaminated device. C. albicans biofilms form through a regulated process of adhesion to surfaces, filamentation, maturation, and ultimately dispersion. To uncover new strategies to block the initial stages of biofilm formation, we utilized a functional genomic approach to identify genes that modulate C. albicans adherence. We screened a library of 1,481 double barcoded doxycycline-repressible conditional gene expression strains covering ~25% of the C. albicans genome. We identified five genes for which transcriptional repression impaired adherence, including: ARC18, PMT1, MNN9, SPT7, and orf19.831. The most severe adherence defect was observed upon transcriptional repression of ARC18, which encodes a member of the Arp2/3 complex that is involved in regulation of the actin cytoskeleton and endocytosis. Depletion of components of the Arp2/3 complex not only impaired adherence, but also caused reduced biofilm formation, increased cell surface hydrophobicity, and increased exposure of cell wall chitin and β-glucans. Reduced function of the Arp2/3 complex led to impaired cell wall integrity and activation of Rho1-mediated cell wall stress responses, thereby causing cell wall remodelling and reduced adherence. Thus, we identify important functional relationships between cell wall stress responses and a novel mechanism that controls adherence and biofilm formation, thereby illuminating novel strategies to cripple a leading fungal pathogen of humans.
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Signaling through Lrg1, Rho1 and Pkc1 Governs Candida albicans Morphogenesis in Response to Diverse Cues. PLoS Genet 2016; 12:e1006405. [PMID: 27788136 PMCID: PMC5082861 DOI: 10.1371/journal.pgen.1006405] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 10/04/2016] [Indexed: 12/22/2022] Open
Abstract
The capacity to transition between distinct morphological forms is a key virulence trait for diverse fungal pathogens. A poignant example of a leading opportunistic fungal pathogen of humans for which an environmentally responsive developmental program underpins virulence is Candida albicans. C. albicans mutants that are defective in the transition between yeast and filamentous forms typically have reduced virulence. Although many positive regulators of C. albicans filamentation have been defined, there are fewer negative regulators that have been implicated in repression of filamentation in the absence of inducing cues. To discover novel negative regulators of filamentation, we screened a collection of 1,248 C. albicans homozygous transposon insertion mutants to identify those that were filamentous in the absence of inducing cues. We identified the Rho1 GAP Lrg1, which represses filamentous growth by stimulating Rho1 GTPase activity and converting Rho1 to its inactive, GDP-bound form. Deletion of LRG1 or introduction of a RHO1 mutation that locks Rho1 in constitutively active, GTP-bound state, leads to filamentation in the absence of inducing cues. Deletion of the Rho1 downstream effector PKC1 results in defective filamentation in response to diverse host-relevant inducing cues, including serum. We further established that Pkc1 is not required to sense filament-inducing cues, but its kinase activity is critical for the initiation of filamentous growth. Our genetic analyses revealed that Pkc1 regulates filamentation independent of the canonical MAP kinase cascade. Further, although Ras1 activation is not impaired in a pkc1Δ/pkc1Δ mutant, adenylyl cyclase activity is reduced, consistent with a model in which Pkc1 functions in parallel with Ras1 in regulating Cyr1 activation. Thus, our findings delineate a signaling pathway comprised of Lrg1, Rho1 and Pkc1 with a core role in C. albicans morphogenesis, and illuminate functional relationships that govern activation of a central transducer of signals that control environmental response and virulence programs.
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33
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Dichtl K, Samantaray S, Wagener J. Cell wall integrity signalling in human pathogenic fungi. Cell Microbiol 2016; 18:1228-38. [DOI: 10.1111/cmi.12612] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 04/19/2016] [Accepted: 05/03/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Karl Dichtl
- Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie; Ludwig-Maximilians-Universität München; 80336 Munich Germany
| | - Sweta Samantaray
- Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie; Ludwig-Maximilians-Universität München; 80336 Munich Germany
- Institute of Microbiology and Infection, School of Biosciences; University of Birmingham; Birmingham UK
| | - Johannes Wagener
- Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie; Ludwig-Maximilians-Universität München; 80336 Munich Germany
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34
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Kosciuczuk EM, Saleiro D, Platanias LC. Dual targeting of eIF4E by blocking MNK and mTOR pathways in leukemia. Cytokine 2016; 89:116-121. [PMID: 27094611 DOI: 10.1016/j.cyto.2016.01.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 01/30/2016] [Indexed: 12/22/2022]
Abstract
Dysregulation of mRNA translation leads to aberrant activation of cellular pathways that promote expansion and survival of leukemic clones. A key element of the initiation translation complex is eIF4E (eukaryotic translation initiation factor 4E). The mitogen-activated protein kinase (MAPK) and mammalian target of rapamycin (mTOR) pathways play important roles in the regulation of eIF4E expression and downstream functional outcomes. Mitogen-activated protein kinase interacting protein kinases (Mnks) control translation by phosphorylation of eIF4E, whereas the mTOR kinase phosphorylates/de-activates the eIF4E inhibitor, 4E-BP1, to release translational repression. Both pathways are often abnormally activated in leukemia cells and promote cell survival events by controlling expression of oncogenic proteins. Targeting these pathways may provide approaches to avoid aberrant proliferation and neoplastic transformation.
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Affiliation(s)
- Ewa M Kosciuczuk
- Robert H. Lurie Comprehensive Cancer Center and Division of Hematology-Oncology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; Department of Medicine, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA.
| | - Diana Saleiro
- Robert H. Lurie Comprehensive Cancer Center and Division of Hematology-Oncology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Leonidas C Platanias
- Robert H. Lurie Comprehensive Cancer Center and Division of Hematology-Oncology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; Department of Medicine, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA
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35
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Han W, Ding Y, Xu Y, Pfister K, Zhu S, Warne B, Doyle M, Aikawa M, Amiri P, Appleton B, Stuart DD, Fanidi A, Shafer CM. Discovery of a Selective and Potent Inhibitor of Mitogen-Activated Protein Kinase-Interacting Kinases 1 and 2 (MNK1/2) Utilizing Structure-Based Drug Design. J Med Chem 2016; 59:3034-45. [DOI: 10.1021/acs.jmedchem.5b01657] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Wooseok Han
- Global
Discovery Chemistry, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Yu Ding
- Global
Discovery Chemistry, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Yongjin Xu
- Global
Discovery Chemistry, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Keith Pfister
- Global
Discovery Chemistry, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Shejin Zhu
- Global
Discovery Chemistry, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Bob Warne
- Oncology, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Mike Doyle
- Oncology, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Mina Aikawa
- Oncology, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Payman Amiri
- Oncology, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Brent Appleton
- Global
Discovery Chemistry, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Darrin D. Stuart
- Oncology, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Abdallah Fanidi
- Oncology, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
| | - Cynthia M. Shafer
- Global
Discovery Chemistry, Novartis Institutes for BioMedical Research, 4560 Horton Street, Emeryville, California 94608, United States
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36
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Baell JB. Feeling Nature's PAINS: Natural Products, Natural Product Drugs, and Pan Assay Interference Compounds (PAINS). JOURNAL OF NATURAL PRODUCTS 2016; 79:616-28. [PMID: 26900761 DOI: 10.1021/acs.jnatprod.5b00947] [Citation(s) in RCA: 360] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We have previously reported on classes of compounds that can interfere with bioassays via a number of different mechanisms and termed such compounds Pan Assay INterference compoundS, or PAINS. These compounds were defined on the basis of high-throughput data derived from vendor-supplied synthetics. The question therefore arises whether the concept of PAINS is relevant to compounds of natural origin. Here, it is shown that this is indeed the case, but that the context of the biological readout is an important factor that must be brought into consideration.
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Affiliation(s)
- Jonathan B Baell
- Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus) , 381 Royal Parade, Parkville, Victoria 3084, Australia
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37
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Wang HX, Douglas LM, Veselá P, Rachel R, Malinsky J, Konopka JB. Eisosomes promote the ability of Sur7 to regulate plasma membrane organization in Candida albicans. Mol Biol Cell 2016; 27:1663-75. [PMID: 27009204 PMCID: PMC4865322 DOI: 10.1091/mbc.e16-01-0065] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/16/2016] [Indexed: 12/15/2022] Open
Abstract
The plasma membrane of the fungal pathogen Candida albicans forms a protective barrier that also mediates many processes needed for virulence, including cell wall synthesis, invasive hyphal morphogenesis, and nutrient uptake. Because compartmentalization of the plasma membrane is believed to coordinate these diverse activities, we examined plasma membrane microdomains termed eisosomes or membrane compartment of Can1 (MCC), which correspond to ∼200-nm-long furrows in the plasma membrane. A pil1∆ lsp1∆ mutant failed to form eisosomes and displayed strong defects in plasma membrane organization and morphogenesis, including extensive cell wall invaginations. Mutation of eisosome proteins Slm2, Pkh2, and Pkh3 did not cause similar cell wall defects, although pkh2∆ cells formed chains of furrows and pkh3∆ cells formed wider furrows, identifying novel roles for the Pkh protein kinases in regulating furrows. In contrast, the sur7∆ mutant formed cell wall invaginations similar to those for the pil1∆ lsp1∆ mutant even though it could form eisosomes and furrows. A PH-domain probe revealed that the regulatory lipid phosphatidylinositol 4,5-bisphosphate was enriched at sites of cell wall invaginations in both the sur7∆ and pil1∆ lsp1∆ cells, indicating that this contributes to the defects. The sur7∆ and pil1∆ lsp1∆ mutants displayed differential susceptibility to various types of stress, indicating that they affect overlapping but distinct functions. In support of this, many mutant phenotypes of the pil1∆ lsp1∆ cells were rescued by overexpressing SUR7 These results demonstrate that C. albicans eisosomes promote the ability of Sur7 to regulate plasma membrane organization.
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Affiliation(s)
- Hong X Wang
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11794-5222
| | - Lois M Douglas
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11794-5222
| | - Petra Veselá
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 142 20 Prague, Czech Republic
| | - Reinhard Rachel
- Centre for Electron Microscopy, Faculty of Biology and Preclinical Medicine, University of Regensburg, 93053 Regensburg, Germany
| | - Jan Malinsky
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 142 20 Prague, Czech Republic
| | - James B Konopka
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11794-5222
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Abstract
The translation initiation factor eIF4E mediates a rate-limiting process that drives selective translation of many oncongenic proteins such as cyclin D1, survivin and VEGF, thereby contributing to tumour growth, metastasis and therapy resistance. As an essential regulatory hub in cancer signalling network, many oncogenic signalling pathways appear to converge on eIF4E. Therefore, targeting eIF4E-mediated cap-dependent translation is considered a promising anticancer strategy. This paper reviews the strategies that can be used to target eIF4E, highlighting agents that target eIF4E activity at each distinct level.
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39
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Darieva Z, Webber A, Warwood S, Sharrocks AD. Protein kinase C coordinates histone H3 phosphorylation and acetylation. eLife 2015; 4:e09886. [PMID: 26468616 PMCID: PMC4714974 DOI: 10.7554/elife.09886] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Accepted: 10/14/2015] [Indexed: 12/11/2022] Open
Abstract
The re-assembly of chromatin following DNA replication is a critical event in the maintenance of genome integrity. Histone H3 acetylation at K56 and phosphorylation at T45 are two important chromatin modifications that accompany chromatin assembly. Here we have identified the protein kinase Pkc1 as a key regulator that coordinates the deposition of these modifications in S. cerevisiae under conditions of replicative stress. Pkc1 phosphorylates the histone acetyl transferase Rtt109 and promotes its ability to acetylate H3K56. Our data also reveal novel cross-talk between two different histone modifications as Pkc1 also enhances H3T45 phosphorylation and this modification is required for H3K56 acetylation. Our data therefore uncover an important role for Pkc1 in coordinating the deposition of two different histone modifications that are important for chromatin assembly. DOI:http://dx.doi.org/10.7554/eLife.09886.001 Prior to cell division, DNA must be copied so that each new cell gets a complete copy of the cell’s genetic instructions. But DNA is so long that it is stored in a heavily compacted form in the nucleus of the cell, with the strands of DNA coiled around several proteins called histones. Before the DNA is copied, it must be unfurled. Then each new copy of DNA must be repackaged to fit compactly inside the nucleus of each new cell. If errors occur in the process of copying DNA, it can lead to genetic mutations that may cause diseases like cancer. To prevent this, cells have mechanisms to identify errors and correct them before the DNA is repackaged. This requires a pause to allow the repairs to occur before the DNA recoils. However, it is not completely clear how this process is controlled. Now, Darieva et al. show that an enzyme called protein kinase C (or Pkc1 for short) is essential to repackaging DNA after the errors are corrected. Several experiments showed that Pkc1 plays an important role when cells were exposed to stressful conditions that potentially cause errors in DNA copying. Specifically, Pkc1 helps prepare the third histone protein (histone H3) so that DNA can recoil around it. Pkc1 waits until the stressful conditions have passed and the DNA has been repaired to make the necessary changes. Once the stress has passed, Pkc1 adds a phosphate to another enzyme called Rtt109 that prepares the histone. The Pkc1 simultaneously contributes to another necessary change to histone H3. These new details about DNA repackaging may help researchers understand how cells protect against DNA copying errors, and how this process goes wrong in cancer. DOI:http://dx.doi.org/10.7554/eLife.09886.002
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Affiliation(s)
- Zoulfia Darieva
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Aaron Webber
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Stacey Warwood
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Andrew D Sharrocks
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
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An integrated approach for discovery of highly potent and selective Mnk inhibitors: Screening, synthesis and SAR analysis. Eur J Med Chem 2015; 103:539-50. [DOI: 10.1016/j.ejmech.2015.09.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 10/07/2014] [Accepted: 09/05/2015] [Indexed: 02/02/2023]
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Basnet SKC, Diab S, Schmid R, Yu M, Yang Y, Gillam TA, Teo T, Li P, Peat T, Albrecht H, Wang S. Identification of a Highly Conserved Allosteric Binding Site on Mnk1 and Mnk2. Mol Pharmacol 2015; 88:935-48. [PMID: 26268528 DOI: 10.1124/mol.115.100131] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 08/11/2015] [Indexed: 12/19/2022] Open
Abstract
Elevated levels of phosphorylated eukaryotic initiation factor 4E (eIF4E) have been implicated in many tumor types, and mitogen activated protein kinase-interacting kinases (Mnks) are the only known kinases that phosphorylate eIF4E at Ser209. The phosphorylation of eIF4E is essential for oncogenic transformation but is of no significance to normal growth and development. Pharmacological inhibition of Mnks therefore provides a nontoxic and effective strategy for cancer therapy. However, a lack of specific Mnk inhibitors has confounded pharmacological target validation and clinical development. Herein, we report the identification of a novel series of Mnk inhibitors and their binding modes. A systematic workflow has been established to distinguish between type III and type I/II inhibitors. A selection of 66 compounds was tested for Mnk1 and Mnk2 inhibition, and 9 out of 20 active compounds showed type III interaction with an allosteric site of the proteins. Most of the type III inhibitors exhibited dual Mnk1 and Mnk2 activities and demonstrated potent antiproliferative properties against the MV4-11 acute myeloid leukemia cell line. Interestingly, ATP-/substrate-competitive inhibitors were found to be highly selective for Mnk2, with little or no activity for Mnk1. Our study suggests that Mnk1 and Mnk2 share a common structure of the allosteric inhibitory binding site but possess different structural features of the ATP catalytic domain. The findings will assist in the future design and development of Mnk targeted anticancer therapeutics.
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Affiliation(s)
- Sunita K C Basnet
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
| | - Sarah Diab
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
| | - Raffaella Schmid
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
| | - Mingfeng Yu
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
| | - Yuchao Yang
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
| | - Todd Alexander Gillam
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
| | - Theodosia Teo
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
| | - Peng Li
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
| | - Tom Peat
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
| | - Hugo Albrecht
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
| | - Shudong Wang
- Centre for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia (S.K.C.B., S.D., R.S., M.Y., Y.Y., T.A.G., T.T., P.L., H.A., S.W.); and CSIRO Biosciences Program, Parkville, Victoria, Australia (T.P.)
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Zhang Z, Ren Q. Why are essential genes essential? - The essentiality of Saccharomyces genes. MICROBIAL CELL 2015; 2:280-287. [PMID: 28357303 PMCID: PMC5349100 DOI: 10.15698/mic2015.08.218] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Essential genes are defined as required for the survival of an organism or a cell. They are of particular interests, not only for their essential biological functions, but also in practical applications, such as identifying effective drug targets to pathogenic bacteria and fungi. The budding yeast Saccharomyces cerevisiae has approximately 6,000 open reading frames, 15 to 20% of which are deemed as essential. Some of the essential genes, however, appear to perform non-essential functions, such as aging and cell death, while many of the non-essential genes play critical roles in cell survival. In this paper, we reviewed and analyzed the levels of essentiality of the Saccharomyces cerevisiae genes and have grouped the genes into four categories: (1) Conditional essential: essential only under certain circumstances or growth conditions; (2) Essential: required for survival under optimal growth conditions; (3) Redundant essential: synthetic lethal due to redundant pathways or gene duplication; and (4) Absolute essential: the minimal genes required for maintaining a cellular life under a stress-free environment. The essential and non-essential functions of the essential genes were further analyzed.
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Affiliation(s)
- Zhaojie Zhang
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
| | - Qun Ren
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
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The Aspergillus fumigatus sitA Phosphatase Homologue Is Important for Adhesion, Cell Wall Integrity, Biofilm Formation, and Virulence. EUKARYOTIC CELL 2015; 14:728-44. [PMID: 25911225 DOI: 10.1128/ec.00008-15] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 04/09/2015] [Indexed: 11/20/2022]
Abstract
Aspergillus fumigatus is an opportunistic pathogenic fungus able to infect immunocompromised patients, eventually causing disseminated infections that are difficult to control and lead to high mortality rates. It is important to understand how the signaling pathways that regulate these factors involved in virulence are orchestrated. Protein phosphatases are central to numerous signal transduction pathways. Here, we characterize the A. fumigatus protein phosphatase 2A SitA, the Saccharomyces cerevisiae Sit4p homologue. The sitA gene is not an essential gene, and we were able to construct an A. fumigatus null mutant. The ΔsitA strain had decreased MpkA phosphorylation levels, was more sensitive to cell wall-damaging agents, had increased β-(1,3)-glucan and chitin, was impaired in biofilm formation, and had decreased protein kinase C activity. The ΔsitA strain is more sensitive to several metals and ions, such as MnCl2, CaCl2, and LiCl, but it is more resistant to ZnSO4. The ΔsitA strain was avirulent in a murine model of invasive pulmonary aspergillosis and induces an augmented tumor necrosis factor alpha (TNF-α) response in mouse macrophages. These results stress the importance of A. fumigatus SitA as a possible modulator of PkcA/MpkA activity and its involvement in the cell wall integrity pathway.
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Cowen LE, Sanglard D, Howard SJ, Rogers PD, Perlin DS. Mechanisms of Antifungal Drug Resistance. Cold Spring Harb Perspect Med 2014; 5:a019752. [PMID: 25384768 DOI: 10.1101/cshperspect.a019752] [Citation(s) in RCA: 354] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Antifungal therapy is a central component of patient management for acute and chronic mycoses. Yet, treatment choices are restricted because of the sparse number of antifungal drug classes. Clinical management of fungal diseases is further compromised by the emergence of antifungal drug resistance, which eliminates available drug classes as treatment options. Once considered a rare occurrence, antifungal drug resistance is on the rise in many high-risk medical centers. Most concerning is the evolution of multidrug- resistant organisms refractory to several different classes of antifungal agents, especially among common Candida species. The mechanisms responsible are mostly shared by both resistant strains displaying inherently reduced susceptibility and those acquiring resistance during therapy. The molecular mechanisms include altered drug affinity and target abundance, reduced intracellular drug levels caused by efflux pumps, and formation of biofilms. New insights into genetic factors regulating these mechanisms, as well as cellular factors important for stress adaptation, provide a foundation to better understand the emergence of antifungal drug resistance.
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Affiliation(s)
- Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Dominique Sanglard
- University of Lausanne and University Hospital Center, Institute of Microbiology, 1011 Lausanne, Switzerland
| | - Susan J Howard
- University of Liverpool, Sherrington Building, Ashton Street, Liverpool L69 3GE, United Kingdom
| | - P David Rogers
- College of Pharmacy, The University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - David S Perlin
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey 07103
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Hayes BME, Anderson MA, Traven A, van der Weerden NL, Bleackley MR. Activation of stress signalling pathways enhances tolerance of fungi to chemical fungicides and antifungal proteins. Cell Mol Life Sci 2014; 71:2651-66. [PMID: 24526056 PMCID: PMC11113482 DOI: 10.1007/s00018-014-1573-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 12/17/2013] [Accepted: 01/20/2014] [Indexed: 10/25/2022]
Abstract
Fungal disease is an increasing problem in both agriculture and human health. Treatment of human fungal disease involves the use of chemical fungicides, which generally target the integrity of the fungal plasma membrane or cell wall. Chemical fungicides used for the treatment of plant disease, have more diverse mechanisms of action including inhibition of sterol biosynthesis, microtubule assembly and the mitochondrial respiratory chain. However, these treatments have limitations, including toxicity and the emergence of resistance. This has led to increased interest in the use of antimicrobial peptides for the treatment of fungal disease in both plants and humans. Antimicrobial peptides are a diverse group of molecules with differing mechanisms of action, many of which remain poorly understood. Furthermore, it is becoming increasingly apparent that stress response pathways are involved in the tolerance of fungi to both chemical fungicides and antimicrobial peptides. These signalling pathways such as the cell wall integrity and high-osmolarity glycerol pathway are triggered by stimuli, such as cell wall instability, changes in osmolarity and production of reactive oxygen species. Here we review stress signalling induced by treatment of fungi with chemical fungicides and antifungal peptides. Study of these pathways gives insight into how these molecules exert their antifungal effect and also into the mechanisms used by fungi to tolerate sub-lethal treatment by these molecules. Inactivation of stress response pathways represents a potential method of increasing the efficacy of antifungal molecules.
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Affiliation(s)
- Brigitte M. E. Hayes
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086 Australia
| | - Marilyn A. Anderson
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086 Australia
| | - Ana Traven
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800 Australia
| | | | - Mark R. Bleackley
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086 Australia
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Schwarzmüller T, Ma B, Hiller E, Istel F, Tscherner M, Brunke S, Ames L, Firon A, Green B, Cabral V, Marcet-Houben M, Jacobsen ID, Quintin J, Seider K, Frohner I, Glaser W, Jungwirth H, Bachellier-Bassi S, Chauvel M, Zeidler U, Ferrandon D, Gabaldón T, Hube B, d'Enfert C, Rupp S, Cormack B, Haynes K, Kuchler K. Systematic phenotyping of a large-scale Candida glabrata deletion collection reveals novel antifungal tolerance genes. PLoS Pathog 2014; 10:e1004211. [PMID: 24945925 PMCID: PMC4063973 DOI: 10.1371/journal.ppat.1004211] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 05/13/2014] [Indexed: 11/28/2022] Open
Abstract
The opportunistic fungal pathogen Candida glabrata is a frequent cause of candidiasis, causing infections ranging from superficial to life-threatening disseminated disease. The inherent tolerance of C. glabrata to azole drugs makes this pathogen a serious clinical threat. To identify novel genes implicated in antifungal drug tolerance, we have constructed a large-scale C. glabrata deletion library consisting of 619 unique, individually bar-coded mutant strains, each lacking one specific gene, all together representing almost 12% of the genome. Functional analysis of this library in a series of phenotypic and fitness assays identified numerous genes required for growth of C. glabrata under normal or specific stress conditions, as well as a number of novel genes involved in tolerance to clinically important antifungal drugs such as azoles and echinocandins. We identified 38 deletion strains displaying strongly increased susceptibility to caspofungin, 28 of which encoding proteins that have not previously been linked to echinocandin tolerance. Our results demonstrate the potential of the C. glabrata mutant collection as a valuable resource in functional genomics studies of this important fungal pathogen of humans, and to facilitate the identification of putative novel antifungal drug target and virulence genes. Clinical infections by the yeast-like pathogen Candida glabrata have been ever-increasing over the past years. Importantly, C. glabrata is one of the most prevalent causes of drug-refractory fungal infections in humans. We have generated a novel large-scale collection encompassing 619 bar-coded C. glabrata mutants, each lacking a single gene. Extensive profiling of phenotypes reveals a number of novel genes implicated in tolerance to antifungal drugs that interfere with proper cell wall function, as well as genes affecting fitness of C. glabrata both during normal growth and under environmental stress. This fungal deletion collection will be a valuable resource for the community to study mechanisms of virulence and antifungal drug tolerance in C. glabrata, which is particularly relevant in view of the increasing prevalence of infections caused by this important human fungal pathogen.
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Affiliation(s)
- Tobias Schwarzmüller
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Biao Ma
- Department of Microbiology, Imperial College London, London, United Kingdom
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Ekkehard Hiller
- Molekulare Biotechnologie MBT Fraunhofer Institut für Grenzflächen- und Bioverfahrenstechnik IGB Fraunhofer, Stuttgart, Germany
| | - Fabian Istel
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Michael Tscherner
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Sascha Brunke
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
- Center for Sepsis Control and Care, CSCC, Jena University Hospital, Jena, Germany
| | - Lauren Ames
- Department of Microbiology, Imperial College London, London, United Kingdom
- Biosciences, College of Life & Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Arnaud Firon
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC2019, Paris, France
| | - Brian Green
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Vitor Cabral
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC2019, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur, Paris, France
| | - Marina Marcet-Houben
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG), Barcelona, Spain
| | - Ilse D. Jacobsen
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
- Center for Sepsis Control and Care, CSCC, Jena University Hospital, Jena, Germany
| | - Jessica Quintin
- UPR 9022 du CNRS, Université de Strasbourg, Equipe Fondation Recherche Médicale, Institut de Biologie Moléculaire et Cellulaire, Strasbourg, France
| | - Katja Seider
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
| | - Ingrid Frohner
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Walter Glaser
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Helmut Jungwirth
- Institut für Molekulare Biowissenschaften, Universität Graz, Graz, Austria
| | - Sophie Bachellier-Bassi
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
| | - Murielle Chauvel
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
| | - Ute Zeidler
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
| | - Dominique Ferrandon
- UPR 9022 du CNRS, Université de Strasbourg, Equipe Fondation Recherche Médicale, Institut de Biologie Moléculaire et Cellulaire, Strasbourg, France
| | - Toni Gabaldón
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Bernhard Hube
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
- Center for Sepsis Control and Care, CSCC, Jena University Hospital, Jena, Germany
| | - Christophe d'Enfert
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC2019, Paris, France
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Steffen Rupp
- Molekulare Biotechnologie MBT Fraunhofer Institut für Grenzflächen- und Bioverfahrenstechnik IGB Fraunhofer, Stuttgart, Germany
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Brendan Cormack
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Ken Haynes
- Department of Microbiology, Imperial College London, London, United Kingdom
- Biosciences, College of Life & Environmental Sciences, University of Exeter, Exeter, United Kingdom
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Karl Kuchler
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
- * E-mail: (CE); (SR); (BC); (KH); (KK)
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UPC2 is universally essential for azole antifungal resistance in Candida albicans. EUKARYOTIC CELL 2014; 13:933-46. [PMID: 24659578 DOI: 10.1128/ec.00221-13] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In Candida albicans, the transcription factor Upc2 is central to the regulation of ergosterol biosynthesis. UPC2-activating mutations contribute to azole resistance, whereas disruption increases azole susceptibility. In the present study, we investigated the relationship of UPC2 to fluconazole susceptibility, particularly in azole-resistant strains. In addition to the reduced fluconazole MIC previously observed with UPC2 disruption, we observed a lower minimum fungicidal concentration (MFC) for a upc2Δ/Δ mutant than for its azole-susceptible parent, SC5314. Moreover, the upc2Δ/Δ mutant was unable to grow on a solid medium containing 10 μg/ml fluconazole and exhibited increased susceptibility and a clear zone of inhibition by Etest. Time-kill analysis showed higher fungistatic activity against the upc2Δ/Δ mutant than against SC5314. UPC2 disruption in strains carrying specific resistance mutations also resulted in reduced MICs and MFCs. UPC2 disruption in a highly azole resistant clinical isolate containing multiple resistance mechanisms likewise resulted in a reduced MIC and MFC. This mutant was unable to grow on a solid medium containing 10 μg/ml fluconazole and exhibited increased susceptibility and a clear zone of inhibition by Etest. Time-kill analysis showed increased fungistatic activity against the upc2Δ/Δ mutant in the resistant background. Microarray analysis showed attenuated induction by fluconazole of genes involved in sterol biosynthesis, iron transport, or iron homeostasis in the absence of UPC2. Taken together, these data demonstrate that the UPC2 transcriptional network is universally essential for azole resistance in C. albicans and represents an attractive target for enhancing azole antifungal activity.
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Synthesis and antiproliferative activity of benzofuran-based analogs of cercosporamide against non-small cell lung cancer cell lines. Eur J Med Chem 2013; 69:823-32. [DOI: 10.1016/j.ejmech.2013.09.013] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 09/03/2013] [Accepted: 09/05/2013] [Indexed: 01/12/2023]
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Vincent BM, Lancaster AK, Scherz-Shouval R, Whitesell L, Lindquist S. Fitness trade-offs restrict the evolution of resistance to amphotericin B. PLoS Biol 2013; 11:e1001692. [PMID: 24204207 PMCID: PMC3812114 DOI: 10.1371/journal.pbio.1001692] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Accepted: 09/05/2013] [Indexed: 11/22/2022] Open
Abstract
The rarity of clinical drug resistance to the antifungal amphotericin B is explained by the extreme costs that resistance mutations impose upon stress responses and virulence factors. The evolution of drug resistance in microbial pathogens provides a paradigm for investigating evolutionary dynamics with important consequences for human health. Candida albicans, the leading fungal pathogen of humans, rapidly evolves resistance to two major antifungal classes, the triazoles and echinocandins. In contrast, resistance to the third major antifungal used in the clinic, amphotericin B (AmB), remains extremely rare despite 50 years of use as monotherapy. We sought to understand this long-standing evolutionary puzzle. We used whole genome sequencing of rare AmB-resistant clinical isolates as well as laboratory-evolved strains to identify and investigate mutations that confer AmB resistance in vitro. Resistance to AmB came at a great cost. Mutations that conferred resistance simultaneously created diverse stresses that required high levels of the molecular chaperone Hsp90 for survival, even in the absence of AmB. This requirement stemmed from severe internal stresses caused by the mutations, which drastically diminished tolerance to external stresses from the host. AmB-resistant mutants were hypersensitive to oxidative stress, febrile temperatures, and killing by neutrophils and also had defects in filamentation and tissue invasion. These strains were avirulent in a mouse infection model. Thus, the costs of evolving resistance to AmB limit the emergence of this phenotype in the clinic. Our work provides a vivid example of the ways in which conflicting selective pressures shape evolutionary trajectories and illustrates another mechanism by which the Hsp90 buffer potentiates the emergence of new phenotypes. Developing antibiotics that deliberately create such evolutionary constraints might offer a strategy for limiting the rapid emergence of drug resistance. The evolution of drug resistance in human pathogens is considered an inevitable consequence of the selective pressures imposed by antimicrobial drugs. Yet resistance to one antifungal drug, amphotericin B (AmB), remains extremely rare despite decades of widespread use. Here we explore the biological mechanisms underlying this conundrum. By examining natural and experimental populations of Candida albicans, we identify multiple mutations that confer resistance to AmB in vitro. As with the evolution of resistance to other antifungals, we find that the chaperone protein Hsp90 is involved in enabling the evolution of resistance to AmB. We also discover, however, that mutations that confer AmB resistance impose massive costs on other aspects of fungal pathogenicity; strains that are resistant to AmB are hypersensitive to attack by the host immune system and are unable to invade and damage host tissue. Thus, the evolution of resistance to AmB is restricted by a tradeoff between tolerance of the drug and the ability to cause disease. We propose that developing new antibiotics for which resistance presents such dire tradeoffs may be a promising strategy to prevent the evolution of resistance.
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Affiliation(s)
- Benjamin Matteson Vincent
- Microbiology Graduate Program, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Alex Kelvin Lancaster
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Ruth Scherz-Shouval
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Luke Whitesell
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Susan Lindquist
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
- Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- * E-mail:
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Arencibia JM, Pastor-Flores D, Bauer AF, Schulze JO, Biondi RM. AGC protein kinases: from structural mechanism of regulation to allosteric drug development for the treatment of human diseases. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:1302-21. [PMID: 23524293 DOI: 10.1016/j.bbapap.2013.03.010] [Citation(s) in RCA: 121] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 03/07/2013] [Indexed: 01/15/2023]
Abstract
The group of AGC protein kinases includes more than 60 protein kinases in the human genome, classified into 14 families: PDK1, AKT/PKB, SGK, PKA, PKG, PKC, PKN/PRK, RSK, NDR, MAST, YANK, DMPK, GRK and SGK494. This group is also widely represented in other eukaryotes, including causative organisms of human infectious diseases. AGC kinases are involved in diverse cellular functions and are potential targets for the treatment of human diseases such as cancer, diabetes, obesity, neurological disorders, inflammation and viral infections. Small molecule inhibitors of AGC kinases may also have potential as novel therapeutic approaches against infectious organisms. Fundamental in the regulation of many AGC kinases is a regulatory site termed the "PIF-pocket" that serves as a docking site for substrates of PDK1. This site is also essential to the mechanism of activation of AGC kinases by phosphorylation and is involved in the allosteric regulation of N-terminal domains of several AGC kinases, such as PKN/PRKs and atypical PKCs. In addition, the C-terminal tail and its interaction with the PIF-pocket are involved in the dimerization of the DMPK family of kinases and may explain the molecular mechanism of allosteric activation of GRKs by GPCR substrates. In this review, we briefly introduce the AGC kinases and their known roles in physiology and disease and the discovery of the PIF-pocket as a regulatory site in AGC kinases. Finally, we summarize the current status and future therapeutic potential of small molecules directed to the PIF-pocket; these molecules can allosterically activate or inhibit the kinase as well as act as substrate-selective inhibitors. This article is part of a Special Issue entitled: Inhibitors of Protein Kinases (2012).
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Affiliation(s)
- José M Arencibia
- Research Group PhosphoSites, Department of Internal Medicine I, Universitätsklinikum Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
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