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Stefanie Pöggeler - One of the best experts on this subject based on the ideXlab platform.
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Sordaria macrospora: 25 years as a model organism for studying the molecular mechanisms of fruiting body development
Applied Microbiology and Biotechnology, 2020Co-Authors: Ines Teichert, Stefanie Pöggeler, Minou NowrousianAbstract:Fruiting bodies are among the most complex multicellular structures formed by fungi, and the molecular mechanisms that regulate their development are far from understood. However, studies with a number of fungal model organisms have started to shed light on this developmental process. One of these model organisms is Sordaria macrospora , a filamentous ascomycete from the order Sordariales . This fungus has been a genetic model organism since the 1950s, but its career as a model organism for molecular genetics really took off in the 1990s, when the establishment of a transformation protocol, a mutant collection, and an indexed cosmid library provided the methods and resources to start revealing the molecular mechanisms of fruiting body development. In the 2000s, “omics” methods were added to the S. macrospora tool box, and by 2020, 58 developmental genes have been identified in this fungus. This review gives a brief overview of major method developments for S. macrospora , and then focuses on recent results characterizing different processes involved in regulating development including several regulatory protein complexes, autophagy, transcriptional and chromatin regulation, and RNA editing. Key points • Sordaria macrospora is a model system for analyzing fungal fruiting body development. • More than 100 developmental mutants are available for S. macrospora. • More than 50 developmental genes have been characterized in S. macrospora.
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Sordaria macrospora : 25 years as a model organism for studying the molecular mechanisms of fruiting body development
Applied microbiology and biotechnology, 2020Co-Authors: Ines Teichert, Stefanie Pöggeler, Minou NowrousianAbstract:Fruiting bodies are among the most complex multicellular structures formed by fungi, and the molecular mechanisms that regulate their development are far from understood. However, studies with a number of fungal model organisms have started to shed light on this developmental process. One of these model organisms is Sordaria macrospora, a filamentous ascomycete from the order Sordariales. This fungus has been a genetic model organism since the 1950s, but its career as a model organism for molecular genetics really took off in the 1990s, when the establishment of a transformation protocol, a mutant collection, and an indexed cosmid library provided the methods and resources to start revealing the molecular mechanisms of fruiting body development. In the 2000s, "omics" methods were added to the S. macrospora tool box, and by 2020, 58 developmental genes have been identified in this fungus. This review gives a brief overview of major method developments for S. macrospora, and then focuses on recent results characterizing different processes involved in regulating development including several regulatory protein complexes, autophagy, transcriptional and chromatin regulation, and RNA editing. KEY POINTS: •Sordaria macrospora is a model system for analyzing fungal fruiting body development. •More than 100 developmental mutants are available for S. macrospora. •More than 50 developmental genes have been characterized in S. macrospora.
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Autophagy genes Smatg8 and Smatg4 are required for fruiting-body development, vegetative growth and ascospore germination in the filamentous ascomycete Sordaria macrospora.
Autophagy, 2013Co-Authors: Oliver Voigt, Stefanie PöggelerAbstract:Autophagy is a tightly controlled degradation process involved in various developmental aspects of eukaryotes. However, its involvement in developmental processes of multicellular filamentous ascomycetes is largely unknown. Here, we analyzed the impact of the autophagic proteins SmATG8 and SmATG4 on the sexual and vegetative development of the filamentous ascomycete Sordaria macrospora. A Saccharomyces cerevisiae complementation assay demonstrated that the S. macrospora Smatg8 and Smatg4 genes can functionally replace the yeast homologs. By generating homokaryotic deletion mutants, we showed that the S. macrospora SmATG8 and SmATG4 orthologs were associated with autophagy-dependent processes. Smatg8 and Smatg4 deletions abolished fruiting-body formation and impaired vegetative growth and ascospore germination, but not hyphal fusion. We demonstrated that SmATG4 was capable of processing the SmATG8 precursor. SmATG8 was localized to autophagosomes, whereas SmATG4 was distributed throughout the cytoplasm of ...
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β carbonic anhydrases play a role in fruiting body development and ascospore germination in the filamentous fungus Sordaria macrospora
PLOS ONE, 2009Co-Authors: Skander Elleuche, Stefanie PöggelerAbstract:Carbon dioxide (CO2) is among the most important gases for all organisms. Its reversible interconversion to bicarbonate (HCO3−) reaches equilibrium spontaneously, but slowly, and can be accelerated by a ubiquitous group of enzymes called carbonic anhydrases (CAs). These enzymes are grouped by their distinct structural features into α-, β-, γ-, δ- and ζ-classes. While physiological functions of mammalian, prokaryotic, plant and algal CAs have been extensively studied over the past years, the role of β-CAs in yeasts and the human pathogen Cryptococcus neoformans has been elucidated only recently, and the function of CAs in multicellular filamentous ascomycetes is mostly unknown. To assess the role of CAs in the development of filamentous ascomycetes, the function of three genes, cas1, cas2 and cas3 (carbonic anhydrase of Sordaria) encoding β-class carbonic anhydrases was characterized in the filamentous ascomycetous fungus Sordaria macrospora. Fluorescence microscopy was used to determine the localization of GFP- and DsRED-tagged CAs. While CAS1 and CAS3 are cytoplasmic enzymes, CAS2 is localized to the mitochondria. To assess the function of the three isoenzymes, we generated knock-out strains for all three cas genes (Δcas1, Δcas2, and Δcas3) as well as all combinations of double mutants. No effect on vegetative growth, fruiting-body and ascospore development was seen in the single mutant strains lacking cas1 or cas3, while single mutant Δcas2 was affected in vegetative growth, fruiting-body development and ascospore germination, and the double mutant strain Δcas1/2 was completely sterile. Defects caused by the lack of cas2 could be partially complemented by elevated CO2 levels or overexpression of cas1, cas3, or a non-mitochondrial cas2 variant. The results suggest that CAs are required for sexual reproduction in filamentous ascomycetes and that the multiplicity of isoforms results in redundancy of specific and non-specific functions.
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Visualization of peroxisomes via SKL-tagged DsRed protein in Sordaria macrospora
Fungal Genetics Reports, 2008Co-Authors: Skander Elleuche, Stefanie PöggelerAbstract:We report the utilization of Discosoma sp. red fluorescent protein DsRed to visualize peroxisomes in the filamentous ascomycete Sordaria macrospora. To achieve labeling of peroxisomes, DsRed was fused to a serine-lysine-leucine tag (SKL). Expression of the DsRed-SKL fusion gene under the control of the Aspergillus nidulans gpd-promoter led to protein import of DsRed into peroxisomes. In this study, we describe our results concerning the construction as well as the application of vector pDsRed-SKL.
Minou Nowrousian - One of the best experts on this subject based on the ideXlab platform.
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Sordaria macrospora: 25 years as a model organism for studying the molecular mechanisms of fruiting body development
Applied Microbiology and Biotechnology, 2020Co-Authors: Ines Teichert, Stefanie Pöggeler, Minou NowrousianAbstract:Fruiting bodies are among the most complex multicellular structures formed by fungi, and the molecular mechanisms that regulate their development are far from understood. However, studies with a number of fungal model organisms have started to shed light on this developmental process. One of these model organisms is Sordaria macrospora , a filamentous ascomycete from the order Sordariales . This fungus has been a genetic model organism since the 1950s, but its career as a model organism for molecular genetics really took off in the 1990s, when the establishment of a transformation protocol, a mutant collection, and an indexed cosmid library provided the methods and resources to start revealing the molecular mechanisms of fruiting body development. In the 2000s, “omics” methods were added to the S. macrospora tool box, and by 2020, 58 developmental genes have been identified in this fungus. This review gives a brief overview of major method developments for S. macrospora , and then focuses on recent results characterizing different processes involved in regulating development including several regulatory protein complexes, autophagy, transcriptional and chromatin regulation, and RNA editing. Key points • Sordaria macrospora is a model system for analyzing fungal fruiting body development. • More than 100 developmental mutants are available for S. macrospora. • More than 50 developmental genes have been characterized in S. macrospora.
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Sordaria macrospora : 25 years as a model organism for studying the molecular mechanisms of fruiting body development
Applied microbiology and biotechnology, 2020Co-Authors: Ines Teichert, Stefanie Pöggeler, Minou NowrousianAbstract:Fruiting bodies are among the most complex multicellular structures formed by fungi, and the molecular mechanisms that regulate their development are far from understood. However, studies with a number of fungal model organisms have started to shed light on this developmental process. One of these model organisms is Sordaria macrospora, a filamentous ascomycete from the order Sordariales. This fungus has been a genetic model organism since the 1950s, but its career as a model organism for molecular genetics really took off in the 1990s, when the establishment of a transformation protocol, a mutant collection, and an indexed cosmid library provided the methods and resources to start revealing the molecular mechanisms of fruiting body development. In the 2000s, "omics" methods were added to the S. macrospora tool box, and by 2020, 58 developmental genes have been identified in this fungus. This review gives a brief overview of major method developments for S. macrospora, and then focuses on recent results characterizing different processes involved in regulating development including several regulatory protein complexes, autophagy, transcriptional and chromatin regulation, and RNA editing. KEY POINTS: •Sordaria macrospora is a model system for analyzing fungal fruiting body development. •More than 100 developmental mutants are available for S. macrospora. •More than 50 developmental genes have been characterized in S. macrospora.
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Additional file 18: of The transcription factor PRO44 and the histone chaperone ASF1 regulate distinct aspects of multicellular development in the filamentous fungus Sordaria macrospora
2018Co-Authors: David Immanuel Schumacher, Ines Teichert, Ramona LĂźtkenhaus, Florian Altegoer, Ulrich KĂźck, Minou NowrousianAbstract:Table S3. Sordaria macrospora strains used in this study. (PDF 288 kb
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Additional file 15: of The transcription factor PRO44 and the histone chaperone ASF1 regulate distinct aspects of multicellular development in the filamentous fungus Sordaria macrospora
2018Co-Authors: David Immanuel Schumacher, Ines Teichert, Ramona LĂźtkenhaus, Florian Altegoer, Ulrich KĂźck, Minou NowrousianAbstract:Figure S13. Multiple alignment of SMAC_09436 (ASM2) orthologs. Orthologs were determined by bidirectional BLASTP analyses. Proteins from the Sordariomycetes Sordaria macrospora (S.m., SMAC_09436), Neurospora crassa (N.c., NCU010258), Podospora anserina (P.a., CDP26737.1), Magnaporthe oryzae (M.o., XP_003720415.1), Fusarium graminearum (F.g., FGRAMPH1_01T14721), and Trichoderma reesei (T.r., XP_006961730.1) were aligned with ClustalX. No clear orthologs outside of the Sordariomycetes could be identified. The GAL4 (GAL4-like Zn2Cys6 binuclear cluster DNA-binding) domain and the fungal_TF_MHR (fungal transcription factor regulatory middle homology region) domain in SMAC_09436 are indicated by black and grey bars, respectively, above the sequence. (PDF 176 kb
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Additional file 6: of The transcription factor PRO44 and the histone chaperone ASF1 regulate distinct aspects of multicellular development in the filamentous fungus Sordaria macrospora
2018Co-Authors: David Immanuel Schumacher, Ines Teichert, Ramona LĂźtkenhaus, Florian Altegoer, Ulrich KĂźck, Minou NowrousianAbstract:Figure S6. Phylogenetic analysis of CRC subunit-containig proteins in ascomycetes. Protein sequences were aligned with Clustal X, and a Neighbor Joining analysis was performed with PAUP* with 1000 bootstrap replicates (bootstrap percentages are given at the branches). Sequences from the following ascomycetes were used for analysis with the CRC-subunit protein CC1G_08669 from the basidiomycete Coprinopsis cinerea (CC1G) as an outgroup: Aspergillus nidulans (ANID), Neurospora crassa (NCU), Pyronema confluens (PCON), Saccharomyces cerevisiae (S.c.), Schizosaccharomyces pombe (S.p.), Sclerotinia sclerotiorum (SS1G), Sordaria macrospora (SMAC), Stagonospora nodorum (SNOT), Tuber melanosporum (GSTUMT). The S. macrospora CRC1 protein is part of a cluster of proteins on a separate branch from the cluster containing the S. cerevisiae and S. pombe Rsc7 proteins. (PDF 131 kb
Ines Teichert - One of the best experts on this subject based on the ideXlab platform.
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Sordaria macrospora: 25 years as a model organism for studying the molecular mechanisms of fruiting body development
Applied Microbiology and Biotechnology, 2020Co-Authors: Ines Teichert, Stefanie Pöggeler, Minou NowrousianAbstract:Fruiting bodies are among the most complex multicellular structures formed by fungi, and the molecular mechanisms that regulate their development are far from understood. However, studies with a number of fungal model organisms have started to shed light on this developmental process. One of these model organisms is Sordaria macrospora , a filamentous ascomycete from the order Sordariales . This fungus has been a genetic model organism since the 1950s, but its career as a model organism for molecular genetics really took off in the 1990s, when the establishment of a transformation protocol, a mutant collection, and an indexed cosmid library provided the methods and resources to start revealing the molecular mechanisms of fruiting body development. In the 2000s, “omics” methods were added to the S. macrospora tool box, and by 2020, 58 developmental genes have been identified in this fungus. This review gives a brief overview of major method developments for S. macrospora , and then focuses on recent results characterizing different processes involved in regulating development including several regulatory protein complexes, autophagy, transcriptional and chromatin regulation, and RNA editing. Key points • Sordaria macrospora is a model system for analyzing fungal fruiting body development. • More than 100 developmental mutants are available for S. macrospora. • More than 50 developmental genes have been characterized in S. macrospora.
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Sordaria macrospora : 25 years as a model organism for studying the molecular mechanisms of fruiting body development
Applied microbiology and biotechnology, 2020Co-Authors: Ines Teichert, Stefanie Pöggeler, Minou NowrousianAbstract:Fruiting bodies are among the most complex multicellular structures formed by fungi, and the molecular mechanisms that regulate their development are far from understood. However, studies with a number of fungal model organisms have started to shed light on this developmental process. One of these model organisms is Sordaria macrospora, a filamentous ascomycete from the order Sordariales. This fungus has been a genetic model organism since the 1950s, but its career as a model organism for molecular genetics really took off in the 1990s, when the establishment of a transformation protocol, a mutant collection, and an indexed cosmid library provided the methods and resources to start revealing the molecular mechanisms of fruiting body development. In the 2000s, "omics" methods were added to the S. macrospora tool box, and by 2020, 58 developmental genes have been identified in this fungus. This review gives a brief overview of major method developments for S. macrospora, and then focuses on recent results characterizing different processes involved in regulating development including several regulatory protein complexes, autophagy, transcriptional and chromatin regulation, and RNA editing. KEY POINTS: •Sordaria macrospora is a model system for analyzing fungal fruiting body development. •More than 100 developmental mutants are available for S. macrospora. •More than 50 developmental genes have been characterized in S. macrospora.
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Additional file 18: of The transcription factor PRO44 and the histone chaperone ASF1 regulate distinct aspects of multicellular development in the filamentous fungus Sordaria macrospora
2018Co-Authors: David Immanuel Schumacher, Ines Teichert, Ramona LĂźtkenhaus, Florian Altegoer, Ulrich KĂźck, Minou NowrousianAbstract:Table S3. Sordaria macrospora strains used in this study. (PDF 288 kb
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Additional file 15: of The transcription factor PRO44 and the histone chaperone ASF1 regulate distinct aspects of multicellular development in the filamentous fungus Sordaria macrospora
2018Co-Authors: David Immanuel Schumacher, Ines Teichert, Ramona LĂźtkenhaus, Florian Altegoer, Ulrich KĂźck, Minou NowrousianAbstract:Figure S13. Multiple alignment of SMAC_09436 (ASM2) orthologs. Orthologs were determined by bidirectional BLASTP analyses. Proteins from the Sordariomycetes Sordaria macrospora (S.m., SMAC_09436), Neurospora crassa (N.c., NCU010258), Podospora anserina (P.a., CDP26737.1), Magnaporthe oryzae (M.o., XP_003720415.1), Fusarium graminearum (F.g., FGRAMPH1_01T14721), and Trichoderma reesei (T.r., XP_006961730.1) were aligned with ClustalX. No clear orthologs outside of the Sordariomycetes could be identified. The GAL4 (GAL4-like Zn2Cys6 binuclear cluster DNA-binding) domain and the fungal_TF_MHR (fungal transcription factor regulatory middle homology region) domain in SMAC_09436 are indicated by black and grey bars, respectively, above the sequence. (PDF 176 kb
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Additional file 6: of The transcription factor PRO44 and the histone chaperone ASF1 regulate distinct aspects of multicellular development in the filamentous fungus Sordaria macrospora
2018Co-Authors: David Immanuel Schumacher, Ines Teichert, Ramona LĂźtkenhaus, Florian Altegoer, Ulrich KĂźck, Minou NowrousianAbstract:Figure S6. Phylogenetic analysis of CRC subunit-containig proteins in ascomycetes. Protein sequences were aligned with Clustal X, and a Neighbor Joining analysis was performed with PAUP* with 1000 bootstrap replicates (bootstrap percentages are given at the branches). Sequences from the following ascomycetes were used for analysis with the CRC-subunit protein CC1G_08669 from the basidiomycete Coprinopsis cinerea (CC1G) as an outgroup: Aspergillus nidulans (ANID), Neurospora crassa (NCU), Pyronema confluens (PCON), Saccharomyces cerevisiae (S.c.), Schizosaccharomyces pombe (S.p.), Sclerotinia sclerotiorum (SS1G), Sordaria macrospora (SMAC), Stagonospora nodorum (SNOT), Tuber melanosporum (GSTUMT). The S. macrospora CRC1 protein is part of a cluster of proteins on a separate branch from the cluster containing the S. cerevisiae and S. pombe Rsc7 proteins. (PDF 131 kb
Ulrich Kuck - One of the best experts on this subject based on the ideXlab platform.
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Sordaria macrospora, a Model System for Fungal Development
Physiology and Genetics, 2009Co-Authors: Ulrich Kuck, Minou Nowrousian, Stefanie Pöggeler, Nicole Nolting, Ines EnghAbstract:The homothallic ascomycete Sordaria macrospora has a long-standing history as a classic genetic model system for conventional tetrad analysis. Further, it serves as a model organism to investigate the formation of fruiting bodies that are generated during the sexual life cycle of this filamentous fungus. The application of several molecular tools, such as DNA-mediated transformation, site-specific recombination or functional genomics to this filamentous fungus makes it an ideal experimental system to uncover the details of multicellular development. The rapid and inexpensive genetic analysis of developmental mutants with distinct and defined morphological defects, together with fluorescence microscopy of recombinant strains carrying GPF-tagged developmental proteins should further unravel the spatio-temporal network of regulatory factors. The sum of these investigations will contribute to our understanding of multicellular differentiation processes in eukaryotic model organisms
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three α subunits of heterotrimeric g proteins and an adenylyl cyclase have distinct roles in fruiting body development in the homothallic fungus Sordaria macrospora
Genetics, 2008Co-Authors: Jens Kamerewerd, Minou Nowrousian, Stefanie Pöggeler, Malin Jansson, Ulrich KuckAbstract:Sordaria macrospora , a self-fertile filamentous ascomycete, carries genes encoding three different α-subunits of heterotrimeric G proteins ( gsa , G protein Sordaria alpha subunit). We generated knockout strains for all three gsa genes (Δgsa1, Δgsa2, and Δgsa3) as well as all combinations of double mutants. Phenotypic analysis of single and double mutants showed that the genes for Gα-subunits have distinct roles in the sexual life cycle. While single mutants show some reduction of fertility, double mutants Δgsa1Δgsa2 and Δgsa1Δgsa3 are completely sterile. To test whether the pheromone receptors PRE1 and PRE2 mediate signaling via distinct Gα-subunits, two recently generated Δpre strains were crossed with all Δgsa strains. Analyses of the corresponding double mutants revealed that compared to GSA2, GSA1 is a more predominant regulator of a signal transduction cascade downstream of the pheromone receptors and that GSA3 is involved in another signaling pathway that also contributes to fruiting body development and fertility. We further isolated the gene encoding adenylyl cyclase (AC) ( sac1 ) for construction of a knockout strain. Analyses of the three ΔgsaΔsac1 double mutants and one Δgsa2Δgsa3Δsac1 triple mutant indicate that SAC1 acts downstream of GSA3, parallel to a GSA1–GSA2-mediated signaling pathway. In addition, the function of STE12 and PRO41, two presumptive signaling components, was investigated in diverse double mutants lacking those developmental genes in combination with the gsa genes. This analysis was further completed by expression studies of the ste12 and pro41 transcripts in wild-type and mutant strains. From the sum of all our data, we propose a model for how different Gα-subunits interact with pheromone receptors, adenylyl cyclase, and STE12 and thus cooperatively regulate sexual development in S. macrospora .
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Comparative sequence analysis of Sordaria macrospora and Neurospora crassa as a means to improve genome annotation
Fungal genetics and biology : FG & B, 2004Co-Authors: Minou Nowrousian, Stefanie Pöggeler, Christian Würtz, Ulrich KuckAbstract:One of the most challenging parts of large scale sequencing projects is the identification of functional elements encoded in a genome. Recently, studies of genomes of up to six different Saccharomyces species have demonstrated that a comparative analysis of genome sequences from closely related species is a powerful approach to identify open reading frames and other functional regions within genomes [Science 301 (2003) 71, Nature 423 (2003) 241]. Here, we present a comparison of selected sequences from Sordaria macrospora to their corresponding Neurospora crassa orthologous regions. Our analysis indicates that due to the high degree of sequence similarity and conservation of overall genomic organization, S. macrospora sequence information can be used to simplify the annotation of the N. crassa genome.
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Mating-type genes from the homothallic fungus Sordaria macrospora are functionally expressed in a heterothallic ascomycete
Genetics, 1997Co-Authors: Stefanie Pöggeler, Ulrich Kuck, Siegfried Risch, Heinz D. OsiewaczAbstract:Homokaryons from the homothallic ascomycte Sordaria macrospora are able to enter the sexual pathway and to form fertile fruiting bodies. To analyze the molecular basis of homothallism and to elucidate the role of mating-products during fruiting body development, we cloned and sequenced the entire S. macrospora mating-type locus. Comparison of the Sordaria mating-type locus with mating-type idiomorphs from the heterothallic ascomycetes Neurospora crassa and Podospora anserina revealed that sequences from both idiomorphs ( A/a and mat –/ mat +, respectively) are contiguous in S. macrospora . DNA sequencing of the S. macrospora mating-type region allowed the identification of four open reading frames (ORFs), which were termed Smt-a1, SmtA-1, SmtA-2 and SmtA-3 . While Smt-a1, SmtA-1 , and SmtA-2 show strong sequence similarities with the corresponding N. crassa mating-type ORFs, SmtA-3 has a chimeric character. It comprises sequences that are similar to the A and a mating-type idiomorph from N. crassa . To determine functionality of the S. macrospora mating-type genes, we show that all ORFs are transcriptionally expressed. Furthermore, we transformed the S. macrospora mating-type genes into mat – and mat + strains of the closely related heterothallic fungus P. anserina . The transformation experiments show that mating-type genes from S. macrospora induce fruiting body formation in P. anserina .
Nick D. Read - One of the best experts on this subject based on the ideXlab platform.
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Perithecium morphogenesis in Sordaria macrospora.
Fungal genetics and biology : FG & B, 2010Co-Authors: Kathryn M. Lord, Nick D. ReadAbstract:The perithecium of the self-fertile ascomycete Sordaria macrospora provides an excellent model in which to analyse fungal multicellular development. This study provides a detailed analysis of perithecium morphogenesis in the wild type and eight developmental mutants of S. macrospora, using a range of correlative microscopical techniques. Fundamentally, perithecia and other complex multicellular structures produced by fungi arise by hyphal aggregation and adhesion, and these processes are followed by specialization and septation of hyphal compartments within the aggregates. Perithecial morphogenesis can be divided into the ascogonial, protoperithecial, and perithecial stages of development. At least 13 specialized, morphologically distinct cell-types are involved in perithecium morphogenesis, and these fall into three basic classes: hyphae, conglutinate cells and spores. Conglutinate cells arise from hyphal adhesion and certain perithecial hyphae develop from conglutinate cells. Various hypha-conglutinate cell transitions play important roles during the development of the perithecial wall and neck.
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Homothallism and heterothallism in Sordaria brevicollis
Mycological Research, 1998Co-Authors: Susan J. Robertson, D. Jeff Bond, Nick D. ReadAbstract:Sordaria brevicollis is a filamentous ascomycete previously considered to be exclusively heterothallic. Here we show that S. brevicollis can exhibit homothallism, and describe the genetic and environmental factors favouring the process. Both mating types can produce perithecia in unmated cultures, but only in the uncrossed perithecia of mtA are ascospores formed (in
