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Hunter RMS, Manchester AD, Gremillion SK, Cantonwine EG. Use of image analysis to assess radial growth of Passalora arachidicola and Nothopassalora personata on solid media. Mycologia 2024; 116:213-225. [PMID: 38085557 DOI: 10.1080/00275514.2023.2280434] [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: 07/18/2023] [Accepted: 10/31/2023] [Indexed: 01/23/2024]
Abstract
Despite significant research on early and late leaf spot diseases of peanut, in vitro study of the respective causal agents, Passalora arachidicola and Nothopassalora personata, has been limited due to cultural challenges that make growth of these fungi difficult to quantify with traditional methods. Studies were conducted to evaluate the practicality of image analysis to assess radial growth and tissue volume by correlating these assessments to dry mass. Image analysis was also used to estimate radial growth rates for these fungi over time. Tissue area and volume were significantly correlated to dry mass for P. arachidicola in two separate experiments, and for N. personata when medium had been removed from tissues prior to dry mass assessments. Tissue area densities were the same for P. arachidicola and Pseudocercospora smilacicola, evaluated as a nonstromatal cercosporoid comparison, whereas tissue volume densities were greater for P. archidicola and N. personata than P. smilacicola. A quadratic relationship was observed between radial growth and incubation time for all isolates evaluated. Growth rates of P. arachidicola isolates were 2 to 4 times faster than N. personata during the first week of incubation and slowed over time. Growth rates of NP18R, a phenotype variant of N. personata, increased after neighboring colonies met and was nearly 2.5 times faster than the fastest rates observed for P. arachidicola. These experiments demonstrate that when fungal tissues are observable, image analysis is a useful assessment tool for P. arachidicola and N. personata. Care should be taken to monitor fungal phenotypic changes in these species because phenotype degeneration can affect growth rates.
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Affiliation(s)
| | | | | | - Emily Gayle Cantonwine
- Department of Biology, Valdosta State University, 1500 N. Patterson Street, Valdosta, Georgia 31698
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2
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Huang H, Mehta A, Kalmanovich J, Anand A, Bejarano MC, Garg T, Khan N, Tonpouwo GK, Shkodina AD, Bardhan M. Immunological and inflammatory effects of infectious diseases in circadian rhythm disruption and future therapeutic directions. Mol Biol Rep 2023; 50:3739-3753. [PMID: 36656437 PMCID: PMC9851103 DOI: 10.1007/s11033-023-08276-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 01/11/2023] [Indexed: 01/20/2023]
Abstract
BACKGROUND Circadian rhythm is characterised by daily variations in biological activity to align with the light and dark cycle. These diurnal variations, in turn, influence physiological functions such as blood pressure, temperature, and sleep-wake cycle. Though it is well established that the circadian pathway is linked to pro-inflammatory responses and circulating immune cells, its association with infectious diseases is widely unknown. OBJECTIVE This comprehensive review aims to describe the association between circadian rhythm and host immune response to various kinds of infection. METHODS We conducted a literature search in databases Pubmed/Medline and Science direct. Our paper includes a comprehensive analysis of findings from articles in English which was related to our hypothesis. FINDINGS Molecular clocks determine circadian rhythm disruption in response to infection, influencing the host's response toward infection. Moreover, there is a complex interplay with intrinsic oscillators of pathogens and the influence of specific infectious processes on the CLOCK: BMAL1 pathway. Such mechanisms vary for bacterial and viral infections, both well studied in the literature. However, less is known about the association of parasitic infections and fungal pathogens with circadian rhythm modulation. CONCLUSION It is shown that bidirectional relationships exist between circadian rhythm disruption and infectious process, which contains interplay between the host's and pathogens' circadian oscillator, immune response, and the influence of specific infectious. Further studies exploring the modulations of circadian rhythm and immunity can offer novel explanations of different susceptibilities to infection and can lead to therapeutic avenues in circadian immune modulation of infectious diseases.
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Affiliation(s)
- Helen Huang
- Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, Dublin, Ireland
| | - Aashna Mehta
- Faculty of Medicine, University of Debrecen, Debrecen, 4032 Hungary
| | | | - Ayush Anand
- B. P. Koirala Institute of Health Sciences, Dharan, Nepal
| | - Maria Chilo Bejarano
- Facultad de Ciencias de la Salud Humana, Universidad Autónoma Gabriel René Moreno, Santa Cruz de la Sierra, Bolivia
| | - Tulika Garg
- Government Medical College and Hospital, Chandigarh, India
| | - Nida Khan
- Jinnah Sindh Medical University, Karachi, Pakistan
| | - Gauvain Kankeu Tonpouwo
- Faculté de Médecine, Université de Lubumbashi, Plaine Tshombé, Lubumbashi, Democratic Republic of the Congo
| | | | - Mainak Bardhan
- ICMR-National Institute of Cholera and Enteric Diseases (NICED), Kolkata, India
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3
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Lee S, Völz R, Song H, Harris W, Lee YH. Characterization of the MYB Genes Reveals Insights Into Their Evolutionary Conservation, Structural Diversity, and Functional Roles in Magnaporthe oryzae. Front Microbiol 2021; 12:721530. [PMID: 34899620 PMCID: PMC8660761 DOI: 10.3389/fmicb.2021.721530] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 10/29/2021] [Indexed: 11/13/2022] Open
Abstract
The myeloblastosis (MYB) transcription factor family is evolutionarily conserved among plants, animals, and fungi, and contributes to their growth and development. We identified and analyzed 10 putative MYB genes in Magnaporthe oryzae (MoMYB) and determined their phylogenetic relationships, revealing high divergence and variability. Although MYB domains are generally defined by three tandem repeats, MoMYBs contain one or two weakly conserved repeats embedded in extensive disordered regions. We characterized the secondary domain organization, disordered segments, and functional contributions of each MoMYB. During infection, MoMYBs are distinctively expressed and can be subdivided into two clades of being either up- or down-regulated. Among these, MoMYB1 and MoMYB8 are up-regulated during infection and vegetative growth, respectively. We found MoMYB1 localized predominantly to the cytosol during the formation of infection structures. ΔMomyb1 exhibited reduced virulence on intact rice leaves corresponding to the diminished ability to form hypha-driven appressorium (HDA). We discovered that MoMYB1 regulates HDA formation on hard, hydrophobic surfaces, whereas host surfaces partially restored HDA formation in ΔMomyb1. Lipid droplet accumulation in hyphal tips and expression of HDA-associated genes were strongly perturbed in ΔMomyb1 indicating genetic interaction of MoMYB1 with downstream components critical to HDA formation. We also found that MoMYB8 is necessary for fungal growth, dark-induced melanization of hyphae, and involved in higher abiotic stress tolerance. Taken together, we revealed a multifaceted picture of the MoMYB family, wherein a low degree of conservation has led to the development of distinct structures and functions, ranging from fungal growth to virulence.
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Affiliation(s)
- Sehee Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul, South Korea
| | - Ronny Völz
- Department of Agricultural Biotechnology, Seoul National University, Seoul, South Korea
| | - Hyeunjeong Song
- Interdisciplinary Program in Agricultural Genomics, Seoul National University, Seoul, South Korea
| | - William Harris
- Department of Agricultural Biotechnology, Seoul National University, Seoul, South Korea
| | - Yong-Hwan Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul, South Korea
- Interdisciplinary Program in Agricultural Genomics, Seoul National University, Seoul, South Korea
- Center for Fungal Genetic Resources, Seoul National University, Seoul, South Korea
- Plant Immunity Research Center, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
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4
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McCorison CB, Goodwin SB. The wheat pathogen Zymoseptoria tritici senses and responds to different wavelengths of light. BMC Genomics 2020; 21:513. [PMID: 32711450 PMCID: PMC7382159 DOI: 10.1186/s12864-020-06899-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 07/08/2020] [Indexed: 12/30/2022] Open
Abstract
Background The ascomycete fungus Zymoseptoria tritici (synonyms: Mycosphaerella graminicola, Septoria tritici) is a major pathogen of wheat that causes the economically important foliar disease Septoria tritici blotch. Despite its importance as a pathogen, little is known about the reaction of this fungus to light. To test for light responses, cultures of Z. tritici were grown in vitro for 16-h days under white, blue or red light, and their transcriptomes were compared with each other and to those obtained from control cultures grown in darkness. Results There were major differences in gene expression with over 3400 genes upregulated in one or more of the light conditions compared to dark, and from 1909 to 2573 genes specifically upregulated in the dark compared to the individual light treatments. Differences between light treatments were lower, ranging from only 79 differentially expressed genes in the red versus blue comparison to 585 between white light and red. Many of the differentially expressed genes had no functional annotations. For those that did, analysis of the Gene Ontology (GO) terms showed that those related to metabolism were enriched in all three light treatments, while those related to growth and communication were more prevalent in the dark. Interestingly, genes for effectors that have been shown previously to be involved in pathogenicity also were upregulated in one or more of the light treatments, suggesting a possible role of light for infection. Conclusions This analysis shows that Z. tritici can sense and respond to light with a huge effect on transcript abundance. High proportions of differentially expressed genes with no functional annotations illuminates the huge gap in our understanding of light responses in this fungus. Differential expression of genes for effectors indicates that light could be important for pathogenicity; unknown effectors may show a similar pattern of transcription. A better understanding of the effects of light on pathogenicity and other biological processes of Z. tritici could help to manage Septoria tritici blotch in the future.
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Affiliation(s)
- Cassandra B McCorison
- Department of Botany and Plant Pathology, Purdue University, 915 West State Street, West Lafayette, IN, 47907-2054, USA
| | - Stephen B Goodwin
- USDA-Agricultural Research Service, Crop Production and Pest Control Research Unit, Department of Botany and Plant Pathology, Purdue University, 915 West State Street, West Lafayette, IN, 47907-2054, USA.
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5
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Kontár S, Varečka L, Híreš M, Kryštofová S, Šimkovič M. Light-induced conidiation of Trichoderma spp. strains is accompanied by development-dependent changes in the Ca 2+ binding to cell walls. Can J Microbiol 2018; 64:856-864. [PMID: 29906398 DOI: 10.1139/cjm-2017-0747] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effect of light on the binding of Ca2+ to mycelia and to cell walls isolated from aerial mycelia of three strains of Trichoderma spp. was studied. Two independent methods were used to measure the total Ca2+ content in mycelia and the Ca2+ bound to cell walls isolated from aerial mycelia. The results of these methods showed that the light-induced formation and maturation of conidia in Trichoderma spp. is accompanied by increased Ca2+ deposition in mycelia and cell walls. Moreover, the cultivation of Trichoderma atroviride F-534 in the presence of 45Ca2+ under circadian illumination showed that radioactivity was exclusively localized in the light-induced conidial rings of aerial mycelia. The fluorescence microscopy of chlortetracycline-stained mycelia showed that the major fraction of Ca2+ was accumulated in conidia and fructification structures, or some intracellular compartments in T. atroviride F-534 grown under circadian illumination, while only a limited amount of Ca2+ was associated with hyphal surfaces. In addition, the study of 45Ca2+ binding to cell walls revealed that T. atroviride F-534 displays both increased 45Ca2+ binding capacity and elevated affinity to 45Ca2+ binding upon illumination. The results indicate that conidia formation and (or) maturation is associated with changes in Ca2+ homeostasis.
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Affiliation(s)
- Szilvia Kontár
- a Institute of Biochemistry and Microbiology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovak Republic.,b Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Bratislava, Slovak Republic
| | - L'udovít Varečka
- a Institute of Biochemistry and Microbiology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovak Republic
| | - Michal Híreš
- a Institute of Biochemistry and Microbiology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovak Republic
| | - Svetlana Kryštofová
- a Institute of Biochemistry and Microbiology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovak Republic
| | - Martin Šimkovič
- a Institute of Biochemistry and Microbiology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovak Republic
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6
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Liversage J, Coetzee MP, Bluhm BH, Berger DK, Crampton BG. LOVe across kingdoms: Blue light perception vital for growth and development in plant–fungal interactions. FUNGAL BIOL REV 2018. [DOI: 10.1016/j.fbr.2017.11.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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7
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Larrondo LF, Canessa P. The Clock Keeps on Ticking: Emerging Roles for Circadian Regulation in the Control of Fungal Physiology and Pathogenesis. Curr Top Microbiol Immunol 2018; 422:121-156. [PMID: 30255278 DOI: 10.1007/82_2018_143] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Tic-tac, tic-tac, the sound of time is familiar to us, yet, it also silently shapes daily biological processes conferring 24-hour rhythms in, among others, cellular and systemic signaling, gene expression, and metabolism. Indeed, circadian clocks are molecular machines that permit temporal control of a variety of processes in individuals, with a close to 24-hour period, optimizing cellular dynamics in synchrony with daily environmental cycles. For over three decades, the molecular bases of these clocks have been extensively described in the filamentous fungus Neurospora crassa, yet, there have been few molecular studies in fungi other than Neurospora, despite evidence of rhythmic phenomena in many fungal species, including pathogenic ones. This chapter will revise the mechanisms underlying clock regulation in the model fungus N. crassa, as well as recent findings obtained in several fungi. In particular, this chapter will review the effect of circadian regulation of virulence and organismal interactions, focusing on the phytopathogen Botrytis cinerea, as well as several entomopathogenic fungi, including the behavior-manipulating species Ophiocordyceps kimflemingiae and Entomophthora muscae. Finally, this review will comment current efforts in the study of mammalian pathogenic fungi, while highlighting recent circadian lessons from parasites such as Trypanosoma and Plasmodium. The clock keeps on ticking, whether we can hear it or not.
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Affiliation(s)
- Luis F Larrondo
- Millennium Institute for Integrative Biology (iBio), Santiago, Chile. .,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.
| | - Paulo Canessa
- Millennium Institute for Integrative Biology (iBio), Santiago, Chile.,Facultad de Ciencias de la Vida, Centro de Biotecnologia Vegetal, Universidad Andres Bello, Santiago, Chile
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8
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de Bekker C, Will I, Hughes DP, Brachmann A, Merrow M. Daily rhythms and enrichment patterns in the transcriptome of the behavior-manipulating parasite Ophiocordyceps kimflemingiae. PLoS One 2017; 12:e0187170. [PMID: 29099875 PMCID: PMC5669440 DOI: 10.1371/journal.pone.0187170] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Accepted: 10/13/2017] [Indexed: 12/22/2022] Open
Abstract
Various parasite-host interactions that involve adaptive manipulation of host behavior display time-of-day synchronization of certain events. One example is the manipulated biting behavior observed in Carpenter ants infected with Ophiocordyceps unilateralis sensu lato. We hypothesized that biological clocks play an important role in this and other parasite-host interactions. In order to identify candidate molecular clock components, we used two general strategies: bioinformatics and transcriptional profiling. The bioinformatics approach was used to identify putative homologs of known clock genes. For transcriptional profiling, RNA-Seq was performed on 48 h time courses of Ophiocordyceps kimflemingiae (a recently named species of the O. unilateralis complex), whose genome has recently been sequenced. Fungal blastospores were entrained in liquid media under 24 h light-dark (LD) cycles and were harvested at 4 h intervals either under LD or continuous darkness. Of all O. kimflemingiae genes, 5.3% had rhythmic mRNAs under these conditions (JTK Cycle, ≤ 0.057 statistical cutoff). Our data further indicates that a significant number of transcription factors have a peaked activity during the light phase (day time). The expression levels of a significant number of secreted enzymes, proteases, toxins and small bioactive compounds peaked during the dark phase or subjective night. These findings support a model whereby this fungal parasite uses its biological clock for phase-specific activity. We further suggest that this may be a general mechanism involved in parasite-host interactions.
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Affiliation(s)
- Charissa de Bekker
- University of Central Florida, Department of Biology, Orlando, Florida, United States of America
- LMU Munich, Institute of Medical Psychology, Faculty of Medicine, Munich, Germany
- LMU Munich, Genetics, Faculty of Biology, Planegg-Martinsried, Germany
- * E-mail:
| | - Ian Will
- University of Central Florida, Department of Biology, Orlando, Florida, United States of America
- LMU Munich, Institute of Medical Psychology, Faculty of Medicine, Munich, Germany
| | - David P. Hughes
- Pennsylvania State University, Departments of Biology and Entomology, University Park, Pennsylvania, United States of America
| | - Andreas Brachmann
- LMU Munich, Genetics, Faculty of Biology, Planegg-Martinsried, Germany
| | - Martha Merrow
- LMU Munich, Institute of Medical Psychology, Faculty of Medicine, Munich, Germany
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9
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Franco DL, Canessa P, Bellora N, Risau-Gusman S, Olivares-Yañez C, Pérez-Lara R, Libkind D, Larrondo LF, Marpegan L. Spontaneous circadian rhythms in a cold-adapted natural isolate of Aureobasidium pullulans. Sci Rep 2017; 7:13837. [PMID: 29062053 PMCID: PMC5653790 DOI: 10.1038/s41598-017-14085-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 09/15/2017] [Indexed: 01/01/2023] Open
Abstract
Circadian systems enable organisms to synchronize their physiology to daily and seasonal environmental changes relying on endogenous pacemakers that oscillate with a period close to 24 h even in the absence of external timing cues. The oscillations are achieved by intracellular transcriptional/translational feedback loops thoroughly characterized for many organisms, but still little is known about the presence and characteristics of circadian clocks in fungi other than Neurospora crassa. We sought to characterize the circadian system of a natural isolate of Aureobasidium pullulans, a cold-adapted yeast bearing great biotechnological potential. A. pullulans formed daily concentric rings that were synchronized by light/dark cycles and were also formed in constant darkness with a period of 24.5 h. Moreover, these rhythms were temperature compensated, as evidenced by experiments conducted at temperatures as low as 10 °C. Finally, the expression of clock-essential genes, frequency, white collar-1, white collar-2 and vivid was confirmed. In summary, our results indicate the existence of a functional circadian clock in A. pullulans, capable of sustaining rhythms at very low temperatures and, based on the presence of conserved clock-gene homologues, suggest a molecular and functional relationship to well-described circadian systems.
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Affiliation(s)
- Diana L Franco
- Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA), Universidad Nacional del Comahue, CONICET, CRUB, San Carlos de Bariloche, Río Negro, Argentina.,Departamento de Física Médica Centro Atómico Bariloche and Instituto Balseiro, CONICET, San Carlos de Bariloche, Río Negro, Argentina
| | - Paulo Canessa
- Centro de Biotecnologia Vegetal, Facultad de Ciencias Biologicas, Universidad Andres Bello, Santiago, Chile.,Millennium Nucleus for Fungal Integrative and Synthetic Biology (MN-FISB), Santiago, Chile
| | - Nicolás Bellora
- Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA), Universidad Nacional del Comahue, CONICET, CRUB, San Carlos de Bariloche, Río Negro, Argentina
| | | | - Consuelo Olivares-Yañez
- Millennium Nucleus for Fungal Integrative and Synthetic Biology (MN-FISB), Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Rodrigo Pérez-Lara
- Millennium Nucleus for Fungal Integrative and Synthetic Biology (MN-FISB), Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Diego Libkind
- Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA), Universidad Nacional del Comahue, CONICET, CRUB, San Carlos de Bariloche, Río Negro, Argentina
| | - Luis F Larrondo
- Millennium Nucleus for Fungal Integrative and Synthetic Biology (MN-FISB), Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Luciano Marpegan
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Buenos Aires, Argentina.
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Koritala BSC, Lee K. Natural Variation of the Circadian Clock in Neurospora. ADVANCES IN GENETICS 2017; 99:1-37. [PMID: 29050553 DOI: 10.1016/bs.adgen.2017.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Most living organisms on earth experience daily and expected changes from the rotation of the earth. For an organism, the ability to predict and prepare for incoming stresses or resources is a very important skill for survival. This cellular process of measuring daily time of the day is collectively called the circadian clock. Because of its fundamental role in survival in nature, there is a great interest in studying the natural variation of the circadian clock. However, characterizing the genetic and molecular mechanisms underlying natural variation of circadian clocks remains a challenging task. In this chapter, we will summarize the progress in studying natural variation of the circadian clock in the successful eukaryotic model Neurospora, which led to discovering many design principles of the molecular mechanisms of the eukaryotic circadian clock. Despite the success of the system in revealing the molecular mechanisms of the circadian clock, Neurospora has not been utilized to extensively study natural variation. We will review the challenges that hindered the natural variation studies in Neurospora, and how they were overcome. We will also review the advantages of Neurospora for natural variation studies. Since Neurospora is the model fungal species for circadian study, it represents over 5 million species of fungi on earth. These fungi play important roles in ecosystems on earth, and as such Neurospora could serve as an important model for understanding the ecological role of natural variation in fungal circadian clocks.
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Affiliation(s)
- Bala S C Koritala
- Department of Biology, Rutgers, The State University of New Jersey, Camden, NJ, United States; Center for Computational and Integrative Biology, Rutgers, The State University of New Jersey, Camden, NJ, United States
| | - Kwangwon Lee
- Department of Biology, Rutgers, The State University of New Jersey, Camden, NJ, United States; Center for Computational and Integrative Biology, Rutgers, The State University of New Jersey, Camden, NJ, United States.
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11
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Lu H, McClung CR, Zhang C. Tick Tock: Circadian Regulation of Plant Innate Immunity. ANNUAL REVIEW OF PHYTOPATHOLOGY 2017; 55:287-311. [PMID: 28590878 DOI: 10.1146/annurev-phyto-080516-035451] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Many living organisms on Earth have evolved the ability to integrate environmental and internal signals to determine time and thereafter adjust appropriately their metabolism, physiology, and behavior. The circadian clock is the endogenous timekeeper critical for multiple biological processes in many organisms. A growing body of evidence supports the importance of the circadian clock for plant health. Plants activate timed defense with various strategies to anticipate daily attacks of pathogens and pests and to modulate responses to specific invaders in a time-of-day-dependent manner (gating). Pathogen infection is also known to reciprocally modulate clock activity. Such a cross talk likely reflects the adaptive nature of plants to coordinate limited resources for growth, development, and defense. This review summarizes recent progress in circadian regulation of plant innate immunity with a focus on the molecular events linking the circadian clock and defense. More and better knowledge of clock-defense cross talk could help to improve disease resistance and productivity in economically important crops.
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Affiliation(s)
- Hua Lu
- Department of Biological Sciences, University of Maryland-Baltimore County, Baltimore, Maryland 21052;
| | - C Robertson McClung
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755
| | - Chong Zhang
- Department of Biological Sciences, University of Maryland-Baltimore County, Baltimore, Maryland 21052;
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12
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Dunlap JC, Loros JJ. Making Time: Conservation of Biological Clocks from Fungi to Animals. Microbiol Spectr 2017; 5:10.1128/microbiolspec.FUNK-0039-2016. [PMID: 28527179 PMCID: PMC5446046 DOI: 10.1128/microbiolspec.funk-0039-2016] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Indexed: 01/03/2023] Open
Abstract
The capacity for biological timekeeping arose at least three times through evolution, in prokaryotic cyanobacteria, in cells that evolved into higher plants, and within the group of organisms that eventually became the fungi and the animals. Neurospora is a tractable model system for understanding the molecular bases of circadian rhythms in the last of these groups, and is perhaps the most intensively studied circadian cell type. Rhythmic processes described in fungi include growth rate, stress responses, developmental capacity, and sporulation, as well as much of metabolism; fungi use clocks to anticipate daily environmental changes. A negative feedback loop comprises the core of the circadian system in fungi and animals. In Neurospora, the best studied fungal model, it is driven by two transcription factors, WC-1 and WC-2, that form the White Collar Complex (WCC). WCC elicits expression of the frq gene. FRQ complexes with other proteins, physically interacts with the WCC, and reduces its activity; the kinetics of these processes is strongly influenced by progressive phosphorylation of FRQ. When FRQ becomes sufficiently phosphorylated that it loses the ability to influence WCC activity, the circadian cycle starts again. Environmental cycles of light and temperature influence frq and FRQ expression and thereby reset the internal circadian clocks. The molecular basis of circadian output is also becoming understood. Taken together, molecular explanations are emerging for all the canonical circadian properties, providing a molecular and regulatory framework that may be extended to many members of the fungal and animal kingdoms, including humans.
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Affiliation(s)
- Jay C Dunlap
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - Jennifer J Loros
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
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13
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Hevia MA, Canessa P, Larrondo LF. Circadian clocks and the regulation of virulence in fungi: Getting up to speed. Semin Cell Dev Biol 2016; 57:147-155. [DOI: 10.1016/j.semcdb.2016.03.021] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/25/2016] [Accepted: 03/29/2016] [Indexed: 11/24/2022]
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14
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Montenegro-Montero A, Canessa P, Larrondo LF. Around the Fungal Clock. ADVANCES IN GENETICS 2015; 92:107-84. [DOI: 10.1016/bs.adgen.2015.09.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Fuller KK, Loros JJ, Dunlap JC. Fungal photobiology: visible light as a signal for stress, space and time. Curr Genet 2014; 61:275-88. [PMID: 25323429 DOI: 10.1007/s00294-014-0451-0] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 08/25/2014] [Accepted: 08/29/2014] [Indexed: 12/25/2022]
Abstract
Visible light is an important source of energy and information for much of life on this planet. Though fungi are neither photosynthetic nor capable of observing adjacent objects, it is estimated that the majority of fungal species display some form of light response, ranging from developmental decision-making to metabolic reprogramming to pathogenesis. As such, advances in our understanding of fungal photobiology will likely reach the broad fields impacted by these organisms, including agriculture, industry and medicine. In this review, we will first describe the mechanisms by which fungi sense light and then discuss the selective advantages likely imparted by their ability to do so.
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Affiliation(s)
- Kevin K Fuller
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA,
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The fungal pathogen Aspergillus fumigatus regulates growth, metabolism, and stress resistance in response to light. mBio 2013; 4:mBio.00142-13. [PMID: 23532976 PMCID: PMC3604765 DOI: 10.1128/mbio.00142-13] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Light is a pervasive environmental factor that regulates development, stress resistance, and even virulence in numerous fungal species. Though much research has focused on signaling pathways in Aspergillus fumigatus, an understanding of how this pathogen responds to light is lacking. In this report, we demonstrate that the fungus does indeed respond to both blue and red portions of the visible spectrum. Included in the A. fumigatus light response is a reduction in conidial germination rates, increased hyphal pigmentation, enhanced resistance to acute ultraviolet and oxidative stresses, and an increased susceptibility to cell wall perturbation. By performing gene deletion analyses, we have found that the predicted blue light receptor LreA and red light receptor FphA play unique and overlapping roles in regulating the described photoresponsive behaviors of A. fumigatus. However, our data also indicate that the photobiology of this fungus is complex and likely involves input from additional photosensory pathways beyond those analyzed here. Finally, whole-genome microarray analysis has revealed that A. fumigatus broadly regulates a variety of metabolic genes in response to light, including those involved in respiration, amino acid metabolism, and metal homeostasis. Together, these data demonstrate the importance of the photic environment on the physiology of A. fumigatus and provide a basis for future studies into this unexplored area of its biology.
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Kim H, Ridenour JB, Dunkle LD, Bluhm BH. Regulation of stomatal tropism and infection by light in Cercospora zeae-maydis: evidence for coordinated host/pathogen responses to photoperiod? PLoS Pathog 2011; 7:e1002113. [PMID: 21829344 PMCID: PMC3145785 DOI: 10.1371/journal.ppat.1002113] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Accepted: 04/25/2011] [Indexed: 01/23/2023] Open
Abstract
Cercospora zeae-maydis causes gray leaf spot of maize, which has become one of the most widespread and destructive diseases of maize in the world. C. zeae-maydis infects leaves through stomata, which is predicated on the ability of the pathogen to perceive stomata and reorient growth accordingly. In this study, the discovery that light was required for C. zeae-maydis to perceive stomata and infect leaves led to the identification of CRP1, a gene encoding a putative blue-light photoreceptor homologous to White Collar-1 (WC-1) of Neurospora crassa. Disrupting CRP1 via homologous recombination revealed roles in multiple aspects of pathogenesis, including tropism of hyphae to stomata, the formation of appressoria, conidiation, and the biosynthesis of cercosporin. CRP1 was also required for photoreactivation after lethal doses of UV exposure. Intriguingly, putative orthologs of CRP1 are central regulators of circadian clocks in other filamentous fungi, raising the possibility that C. zeae-maydis uses light as a key environmental input to coordinate pathogenesis with maize photoperiodic responses. This study identified a novel molecular mechanism underlying stomatal tropism in a foliar fungal pathogen, provides specific insight into how light regulates pathogenesis in C. zeae-maydis, and establishes a genetic framework for the molecular dissection of infection via stomata and the integration of host and pathogen responses to photoperiod.
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Affiliation(s)
- Hun Kim
- Department of Plant Pathology, University of Arkansas, Fayetteville, Arkansas, United States of America
| | - John B. Ridenour
- Department of Plant Pathology, University of Arkansas, Fayetteville, Arkansas, United States of America
| | - Larry D. Dunkle
- Crop Production and Pest Control Research Unit, USDA-ARS, Purdue University, West Lafayette, Indiana, United States of America
| | - Burton H. Bluhm
- Department of Plant Pathology, University of Arkansas, Fayetteville, Arkansas, United States of America
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