Publications by authors named "Gerhard H Braus"

166 Publications

Secondary metabolites of Hülle cells mediate protection of fungal reproductive and overwintering structures against fungivorous animals.

Elife 2021 10 12;10. Epub 2021 Oct 12.

University of Göttingen, Molecular Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Göttingen, Germany.

Fungal Hülle cells with nuclear storage and developmental backup functions are reminiscent of multipotent stem cells. In the soil, Hülle cells nurse the overwintering fruiting bodies of . The genome of harbors genes for the biosynthesis of xanthones. We show that enzymes and metabolites of this biosynthetic pathway accumulate in Hülle cells under the control of the regulatory velvet complex, which coordinates development and secondary metabolism. Deletion strains blocked in the conversion of anthraquinones to xanthones accumulate emodins and are delayed in maturation and growth of fruiting bodies. Emodin represses fruiting body and resting structure formation in other fungi. Xanthones are not required for sexual development but exert antifeedant effects on fungivorous animals such as springtails and woodlice. Our findings reveal a novel role of Hülle cells in establishing secure niches for by accumulating metabolites with antifeedant activity that protect reproductive structures from animal predators.
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http://dx.doi.org/10.7554/eLife.68058DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8510581PMC
October 2021

α-Synuclein Decreases the Abundance of Proteasome Subunits and Alters Ubiquitin Conjugates in Yeast.

Cells 2021 Aug 28;10(9). Epub 2021 Aug 28.

Department of Molecular Microbiology and Genetics, Institute for Microbiology and Genetics, University of Göttingen, 37077 Göttingen, Germany.

Parkinson's disease (PD) is the most prevalent movement disorder characterized with loss of dopaminergic neurons in the brain. One of the pathological hallmarks of the disease is accumulation of aggregated α-synuclein (αSyn) in cytoplasmic Lewy body inclusions that indicates significant dysfunction of protein homeostasis in PD. Accumulation is accompanied with highly elevated S129 phosphorylation, suggesting that this posttranslational modification is linked to pathogenicity and altered αSyn inclusion dynamics. To address the role of S129 phosphorylation on protein dynamics further we investigated the wild type and S129A variants using yeast and a tandem fluorescent timer protein reporter approach to monitor protein turnover and stability. Overexpression of both variants leads to inhibited yeast growth. Soluble S129A is more stable and additional Y133F substitution permits αSyn degradation in a phosphorylation-independent manner. Quantitative cellular proteomics revealed significant αSyn-dependent disturbances of the cellular protein homeostasis, which are increased upon S129 phosphorylation. Disturbances are characterized by decreased abundance of the ubiquitin-dependent protein degradation machinery. Biotin proximity labelling revealed that αSyn interacts with the Rpt2 base subunit. Proteasome subunit depletion by reducing the expression of the corresponding genes enhances αSyn toxicity. Our studies demonstrate that turnover of αSyn and depletion of the proteasome pool correlate in a complex relationship between altered proteasome composition and increased αSyn toxicity.
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http://dx.doi.org/10.3390/cells10092229DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8468666PMC
August 2021

The role of Aspergillus nidulans polo-like kinase PlkA in microtubule-organizing center control.

J Cell Sci 2021 08 19;134(16). Epub 2021 Aug 19.

Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany.

Centrosomes are important microtubule-organizing centers (MTOC) in animal cells. In addition, non-centrosomal MTOCs (ncMTOCs) have been described in many cell types. The functional analogs of centrosomes in fungi are the spindle pole bodies (SPBs). In Aspergillus nidulans, additional MTOCs have been discovered at septa (sMTOC). Although the core components are conserved in both MTOCs, their composition and organization are different and dynamic. Here, we show that the polo-like kinase PlkA binds the γ-tubulin ring complex (γ-TuRC) receptor protein ApsB and contributes to targeting ApsB to both MTOCs. PlkA coordinates the activities of the SPB outer plaque and the sMTOC. PlkA kinase activity was required for astral MT formation involving ApsB recruitment. PlkA also interacted with the γ-TuRC inner plaque receptor protein PcpA. Mitosis was delayed without PlkA, and the PlkA protein was required for proper mitotic spindle morphology, although this function was independent of its catalytic activity. Our results suggest that the polo-like kinase is a regulator of MTOC activities and acts as a scaffolding unit through interaction with γ-TuRC receptors.
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http://dx.doi.org/10.1242/jcs.256537DOI Listing
August 2021

Dynamic and Reversible Aggregation of the Human CAP Superfamily Member GAPR-1 in Protein Inclusions in Saccharomyces cerevisiae.

J Mol Biol 2021 Sep 21;433(19):167162. Epub 2021 Jul 21.

Division of Cell Biology, Metabolism and Cancer, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands. Electronic address:

Many proteins that can assemble into higher order structures termed amyloids can also concentrate into cytoplasmic inclusions via liquid-liquid phase separation. Here, we study the assembly of human Golgi-Associated plant Pathogenesis Related protein 1 (GAPR-1), an amyloidogenic protein of the Cysteine-rich secretory proteins, Antigen 5, and Pathogenesis-related 1 proteins (CAP) protein superfamily, into cytosolic inclusions in Saccharomyces cerevisiae. Overexpression of GAPR-1-GFP results in the formation GAPR-1 oligomers and fluorescent inclusions in yeast cytosol. These cytosolic inclusions are dynamic and reversible organelles that gradually increase during time of overexpression and decrease after promoter shut-off. Inclusion formation is, however, a regulated process that is influenced by factors other than protein expression levels. We identified N-myristoylation of GAPR-1 as an important determinant at early stages of inclusion formation. In addition, mutations in the conserved metal-binding site (His54 and His103) enhanced inclusion formation, suggesting that these residues prevent uncontrolled protein sequestration. In agreement with this, we find that addition of Zn metal ions enhances inclusion formation. Furthermore, Zn reduces GAPR-1 protein degradation, which indicates stabilization of GAPR-1 in inclusions. We propose that the properties underlying both the amyloidogenic properties and the reversible sequestration of GAPR-1 into inclusions play a role in the biological function of GAPR-1 and other CAP family members.
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http://dx.doi.org/10.1016/j.jmb.2021.167162DOI Listing
September 2021

LDIP cooperates with SEIPIN and LDAP to facilitate lipid droplet biogenesis in Arabidopsis.

Plant Cell 2021 Sep;33(9):3076-3103

Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G 2W1, Canada.

Cytoplasmic lipid droplets (LDs) are evolutionarily conserved organelles that store neutral lipids and play critical roles in plant growth, development, and stress responses. However, the molecular mechanisms underlying their biogenesis at the endoplasmic reticulum (ER) remain obscure. Here we show that a recently identified protein termed LD-associated protein [LDAP]-interacting protein (LDIP) works together with both endoplasmic reticulum-localized SEIPIN and the LD-coat protein LDAP to facilitate LD formation in Arabidopsis thaliana. Heterologous expression in insect cells demonstrated that LDAP is required for the targeting of LDIP to the LD surface, and both proteins are required for the production of normal numbers and sizes of LDs in plant cells. LDIP also interacts with SEIPIN via a conserved hydrophobic helix in SEIPIN and LDIP functions together with SEIPIN to modulate LD numbers and sizes in plants. Further, the co-expression of both proteins is required to restore normal LD production in SEIPIN-deficient yeast cells. These data, combined with the analogous function of LDIP to a mammalian protein called LD Assembly Factor 1, are discussed in the context of a new model for LD biogenesis in plant cells with evolutionary connections to LD biogenesis in other eukaryotes.
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http://dx.doi.org/10.1093/plcell/koab179DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8462815PMC
September 2021

Strains Induce Transcriptional and Morphological Changes and Reduce Root Colonization of spp.

Front Microbiol 2021 24;12:652468. Epub 2021 May 24.

Institute of Microbiology and Genetics, Göttingen Center for Molecular Biosciences, Georg-August-Universität Göttingen, Göttingen, Germany.

Phytopathogenic Verticillia cause Verticillium wilt on numerous economically important crops. Plant infection begins at the roots, where the fungus is confronted with rhizosphere inhabiting bacteria. The effects of different fluorescent pseudomonads, including some known biocontrol agents of other plant pathogens, on fungal growth of the haploid and/or the amphidiploid were compared on pectin-rich medium, in microfluidic interaction channels, allowing visualization of single hyphae, or on roots. We found that the potential for formation of bacterial lipopeptide syringomycin resulted in stronger growth reduction effects on saprophytic compared to spp. A more detailed analyses on bacterial-fungal co-cultivation in narrow interaction channels of microfluidic devices revealed that the strongest inhibitory potential was found for CHA0, with its inhibitory potential depending on the presence of the GacS/GacA system controlling several bacterial metabolites. Hyphal tip polarity was altered when was confronted with pseudomonads in narrow interaction channels, resulting in a curly morphology instead of straight hyphal tip growth. These results support the hypothesis that the fungus attempts to evade the bacterial confrontation. Alterations due to co-cultivation with bacteria could not only be observed in fungal morphology but also in fungal transcriptome. CHA0 alters transcriptional profiles of during 2 h liquid media co-cultivation in pectin-rich medium. Genes required for degradation of and growth on the carbon source pectin were down-regulated, whereas transcripts involved in redox processes were up-regulated. Thus, the secondary metabolite mediated effect of isolates on species results in a complex transcriptional response, leading to decreased growth with precautions for self-protection combined with the initiation of a change in fungal growth direction. This interplay of bacterial effects on the pathogen can be beneficial to protect plants from infection, as shown with . root experiments. Treatment of the roots with bacteria prior to infection with resulted in a significant reduction of fungal root colonization. Taken together we demonstrate how pseudomonads interfere with the growth of spp. and show that these bacteria could serve in plant protection.
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http://dx.doi.org/10.3389/fmicb.2021.652468DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8180853PMC
May 2021

A 20-kb lineage-specific genomic region tames virulence in pathogenic amphidiploid Verticillium longisporum.

Mol Plant Pathol 2021 Aug 5;22(8):939-953. Epub 2021 May 5.

Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany.

Amphidiploid fungal Verticillium longisporum strains Vl43 and Vl32 colonize the plant host Brassica napus but differ in their ability to cause disease symptoms. These strains represent two V. longisporum lineages derived from different hybridization events of haploid parental Verticillium strains. Vl32 and Vl43 carry same-sex mating-type genes derived from both parental lineages. Vl32 and Vl43 similarly colonize and penetrate plant roots, but asymptomatic Vl32 proliferation in planta is lower than virulent Vl43. The highly conserved Vl43 and Vl32 genomes include less than 1% unique genes, and the karyotypes of 15 or 16 chromosomes display changed genetic synteny due to substantial genomic reshuffling. A 20 kb Vl43 lineage-specific (LS) region apparently originating from the Verticillium dahliae-related ancestor is specific for symptomatic Vl43 and encodes seven genes, including two putative transcription factors. Either partial or complete deletion of this LS region in Vl43 did not reduce virulence but led to induction of even more severe disease symptoms in rapeseed. This suggests that the LS insertion in the genome of symptomatic V. longisporum Vl43 mediates virulence-reducing functions, limits damage on the host plant, and therefore tames Vl43 from being even more virulent.
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http://dx.doi.org/10.1111/mpp.13071DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8295516PMC
August 2021

EARLY RESPONSIVE TO DEHYDRATION 7 Localizes to Lipid Droplets via Its Senescence Domain.

Front Plant Sci 2021 14;12:658961. Epub 2021 Apr 14.

Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada.

Lipid droplets (LDs) are neutral-lipid-containing organelles found in all kingdoms of life and are coated with proteins that carry out a vast array of functions. Compared to mammals and yeast, relatively few LD proteins have been identified in plants, particularly those associated with LDs in vegetative (non-seed) cell types. Thus, to better understand the cellular roles of LDs in plants, a more comprehensive inventory and characterization of LD proteins is required. Here, we performed a proteomics analysis of LDs isolated from drought-stressed leaves and identified EARLY RESPONSIVE TO DEHYDRATION 7 (ERD7) as a putative LD protein. mCherry-tagged ERD7 localized to both LDs and the cytosol when ectopically expressed in plant cells, and the protein's C-terminal senescence domain (SD) was both necessary and sufficient for LD targeting. Phylogenetic analysis revealed that ERD7 belongs to a six-member family in that, along with homologs in other plant species, is separated into two distinct subfamilies. Notably, the SDs of proteins from each subfamily conferred targeting to either LDs or mitochondria. Further, the SD from the ERD7 homolog in humans, spartin, localized to LDs in plant cells, similar to its localization in mammals; although, in mammalian cells, spartin also conditionally localizes to other subcellular compartments, including mitochondria. Disruption of gene expression in revealed no obvious changes in LD numbers or morphology under normal growth conditions, although this does not preclude a role for ERD7 in stress-induced LD dynamics. Consistent with this possibility, a yeast two-hybrid screen using ERD7 as bait identified numerous proteins involved in stress responses, including some that have been identified in other LD proteomes. Collectively, these observations provide new insight to ERD7 and the SD-containing family of proteins in plants and suggest that ERD7 may be involved in functional aspects of plant stress response that also include localization to the LD surface.
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http://dx.doi.org/10.3389/fpls.2021.658961DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8079945PMC
April 2021

Unfolded Protein Response and Scaffold Independent Pheromone MAP Kinase Signaling Control Growth, Development, and Plant Pathogenesis.

J Fungi (Basel) 2021 Apr 15;7(4). Epub 2021 Apr 15.

Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, 37077 Göttingen, Germany.

Differentiation, growth, and virulence of the vascular plant pathogen depend on a network of interconnected cellular signaling cascades. The transcription factor Hac1 of the endoplasmic reticulum-associated unfolded protein response (UPR) is required for initial root colonization, fungal growth, and vascular propagation by conidiation. Hac1 is essential for the formation of microsclerotia as long-time survival resting structures in the field. Single endoplasmic reticulum-associated enzymes for linoleic acid production as precursors for oxylipin signal molecules support fungal growth but not pathogenicity. Microsclerotia development, growth, and virulence further require the pheromone response mitogen-activated protein kinase (MAPK) pathway, but without the Ham5 scaffold function. The MAPK phosphatase Rok1 limits resting structure development of , but promotes growth, conidiation, and virulence. The interplay between UPR and MAPK signaling cascades includes several potential targets for fungal growth control for supporting disease management of the vascular pathogen .
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http://dx.doi.org/10.3390/jof7040305DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8071499PMC
April 2021

Identification of Two Novel Peptides That Inhibit α-Synuclein Toxicity and Aggregation.

Front Mol Neurosci 2021 12;14:659926. Epub 2021 Apr 12.

Department of Molecular Microbiology and Genetics, Institute for Microbiology and Genetics, University of Goettingen, Göttingen, Germany.

Aggregation of α-synuclein (αSyn) into proteinaceous deposits is a pathological hallmark of a range of neurodegenerative diseases including Parkinson's disease (PD). Numerous lines of evidence indicate that the accumulation of toxic oligomeric and prefibrillar αSyn species may underpin the cellular toxicity and spread of pathology between cells. Therefore, aggregation of αSyn is considered a priority target for drug development, as aggregation inhibitors are expected to reduce αSyn toxicity and serve as therapeutic agents. Here, we used the budding yeast as a platform for the identification of short peptides that inhibit αSyn aggregation and toxicity. A library consisting of approximately one million peptide variants was utilized in two high-throughput screening approaches for isolation of library representatives that reduce αSyn-associated toxicity and aggregation. Seven peptides were isolated that were able to suppress specifically αSyn toxicity and aggregation in living cells. Expression of the peptides in yeast reduced the accumulation of αSyn-induced reactive oxygen species and increased cell viability. Next, the peptides were chemically synthesized and probed for their ability to modulate αSyn aggregation . Two synthetic peptides, K84s and K102s, of 25 and 19 amino acids, respectively, significantly inhibited αSyn oligomerization and aggregation at sub-stoichiometric molar ratios. Importantly, K84s reduced αSyn aggregation in human cells. These peptides represent promising αSyn aggregation antagonists for the development of future therapeutic interventions.
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http://dx.doi.org/10.3389/fnmol.2021.659926DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072481PMC
April 2021

The velvet protein Vel1 controls initial plant root colonization and conidia formation for xylem distribution in Verticillium wilt.

PLoS Genet 2021 03 15;17(3):e1009434. Epub 2021 Mar 15.

Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Göttingen and Göttingen Center for Molecular Biosciences (GZMB), Göttingen, Germany.

The conserved fungal velvet family regulatory proteins link development and secondary metabolite production. The velvet domain for DNA binding and dimerization is similar to the structure of the Rel homology domain of the mammalian NF-κB transcription factor. A comprehensive study addressed the functions of all four homologs of velvet domain encoding genes in the fungal life cycle of the soil-borne plant pathogenic fungus Verticillium dahliae. Genetic, cell biological, proteomic and metabolomic analyses of Vel1, Vel2, Vel3 and Vos1 were combined with plant pathogenicity experiments. Different phases of fungal growth, development and pathogenicity require V. dahliae velvet proteins, including Vel1-Vel2, Vel2-Vos1 and Vel3-Vos1 heterodimers, which are already present during vegetative hyphal growth. The major novel finding of this study is that Vel1 is necessary for initial plant root colonization and together with Vel3 for propagation in planta by conidiation. Vel1 is needed for disease symptom induction in tomato. Vel1, Vel2, and Vel3 control the formation of microsclerotia in senescent plants. Vel1 is the most important among all four V. dahliae velvet proteins with a wide variety of functions during all phases of the fungal life cycle in as well as ex planta.
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http://dx.doi.org/10.1371/journal.pgen.1009434DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7993770PMC
March 2021

Draft Genome Sequence of Saccharomyces cerevisiae LW2591Y, a Laboratory Strain for Multigene Assemblies.

Microbiol Resour Announc 2021 Mar 4;10(9). Epub 2021 Mar 4.

Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August-Universität Göttingen, Göttingen, Germany

is an industrially preferred cell factory for the heterologous production of proteins and chemicals. Here, we present the draft genome sequence of the laboratory strain LW2591Y, which has been designed for robust and efficient assembly of multigene pathways.
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http://dx.doi.org/10.1128/MRA.01418-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7936637PMC
March 2021

DEAD-box RNA helicase Dbp4/DDX10 is an enhancer of α-synuclein toxicity and oligomerization.

PLoS Genet 2021 03 3;17(3):e1009407. Epub 2021 Mar 3.

Department of Molecular Microbiology and Genetics, Institute for Microbiology and Genetics, University of Goettingen, Göttingen, Germany.

Parkinson's disease is a neurodegenerative disorder associated with misfolding and aggregation of α-synuclein as a hallmark protein. Two yeast strain collections comprising conditional alleles of essential genes were screened for the ability of each allele to reduce or improve yeast growth upon α-synuclein expression. The resulting 98 novel modulators of α-synuclein toxicity clustered in several major categories including transcription, rRNA processing and ribosome biogenesis, RNA metabolism and protein degradation. Furthermore, expression of α-synuclein caused alterations in pre-rRNA transcript levels in yeast and in human cells. We identified the nucleolar DEAD-box helicase Dbp4 as a prominent modulator of α-synuclein toxicity. Downregulation of DBP4 rescued cells from α-synuclein toxicity, whereas overexpression led to a synthetic lethal phenotype. We discovered that α-synuclein interacts with Dbp4 or its human ortholog DDX10, sequesters the protein outside the nucleolus in yeast and in human cells, and stabilizes a fraction of α-synuclein oligomeric species. These findings provide a novel link between nucleolar processes and α-synuclein mediated toxicity with DDX10 emerging as a promising drug target.
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http://dx.doi.org/10.1371/journal.pgen.1009407DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7928443PMC
March 2021

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition).

Autophagy 2021 Jan 8;17(1):1-382. Epub 2021 Feb 8.

University of Crete, School of Medicine, Laboratory of Clinical Microbiology and Microbial Pathogenesis, Voutes, Heraklion, Crete, Greece; Foundation for Research and Technology, Institute of Molecular Biology and Biotechnology (IMBB), Heraklion, Crete, Greece.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
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http://dx.doi.org/10.1080/15548627.2020.1797280DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7996087PMC
January 2021

Novel Fus3- and Ste12-interacting protein FsiA activates cell fusion-related genes in both Ste12-dependent and -independent manners in Ascomycete filamentous fungi.

Mol Microbiol 2021 04 24;115(4):723-738. Epub 2020 Nov 24.

Department of Biotechnology, The University of Tokyo, Tokyo, Japan.

Filamentous fungal cells, unlike yeasts, fuse during vegetative growth. The orthologs of mitogen-activated protein (MAP) kinase Fus3 and transcription factor Ste12 are commonly involved in the regulation of cell fusion. However, the specific regulatory mechanisms underlying cell fusion in filamentous fungi have not been revealed. In the present study, we identified the novel protein FsiA as an AoFus3- and AoSte12-interacting protein in the filamentous fungus Aspergillus oryzae. The expression of AonosA and cell fusion-related genes decreased upon fsiA deletion and increased with fsiA overexpression, indicating that FsiA is a positive regulator of cell fusion. In addition, the induction of cell fusion-related genes by fsiA overexpression was also observed in the Aoste12 deletion mutant, indicating that FsiA can induce the cell fusion-related genes in an AoSte12-independent manner. Surprisingly, the fsiA and Aoste12 double deletion mutant exhibited higher cell fusion efficiency and increased mRNA levels of the cell fusion-related genes as compared to the fsiA single deletion mutant, which revealed that AoSte12 represses the cell fusion-related genes in the fsiA deletion mutant. Taken together, our data demonstrate that FsiA activates the cell fusion-related genes by suppressing the negative function of AoSte12 as well as by an AoSte12-independent mechanism.
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http://dx.doi.org/10.1111/mmi.14639DOI Listing
April 2021

Production of the Fragrance Geraniol in Peroxisomes of a Product-Tolerant Baker's Yeast.

Front Bioeng Biotechnol 2020 23;8:582052. Epub 2020 Sep 23.

Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August-Universität Göttingen, Göttingen, Germany.

Monoterpenoids, such as the plant metabolite geraniol, are of high industrial relevance since they are important fragrance materials for perfumes, cosmetics, and household products. Chemical synthesis or extraction from plant material for industry purposes are complex, environmentally harmful or expensive and depend on seasonal variations. Heterologous microbial production offers a cost-efficient and sustainable alternative but suffers from low metabolic flux of the precursors and toxicity of the monoterpenoid to the cells. In this study, we evaluated two approaches to counteract both issues by compartmentalizing the biosynthetic enzymes for geraniol to the peroxisomes of as production sites and by improving the geraniol tolerance of the yeast cells. The combination of both approaches led to an 80% increase in the geraniol titers. In the future, the inclusion of product tolerance and peroxisomal compartmentalization into the general chassis engineering toolbox for monoterpenoids or other host-damaging, industrially relevant metabolites may lead to an efficient, low-cost, and eco-friendly microbial production for industrial purposes.
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http://dx.doi.org/10.3389/fbioe.2020.582052DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7546902PMC
September 2020

Elicits Media-Dependent Secretome Responses With Capacity to Distinguish Between Plant-Related Environments.

Front Microbiol 2020 6;11:1876. Epub 2020 Aug 6.

Department of Molecular Microbiology and Genetics, Göttingen Center for Molecular Biosciences, Institute of Microbiology and Genetics, University of Göttingen, Göttingen, Germany.

Verticillia cause a vascular wilt disease affecting a broad range of economically valuable crops. The fungus enters its host plants through the roots and colonizes the vascular system. It requires extracellular proteins for a successful plant colonization. The exoproteomes of the allodiploid upon cultivation in different media or xylem sap extracted from its host plant were compared. Secreted fungal proteins were identified by label free liquid chromatography-tandem mass spectrometry screening. induced two main secretion patterns. One response pattern was elicited in various non-plant related environments. The second pattern includes the exoprotein responses to the plant-related media, pectin-rich simulated xylem medium and pure xylem sap, which exhibited similar but additional distinct features. These exoproteomes include a shared core set of 221 secreted and similarly enriched fungal proteins. The pectin-rich medium significantly induced the secretion of 143 proteins including a number of pectin degrading enzymes, whereas xylem sap triggered a smaller but unique fungal exoproteome pattern with 32 enriched proteins. The latter pattern included proteins with domains of known pathogenicity factors, metallopeptidases and carbohydrate-active enzymes. The most abundant proteins of these different groups are the necrosis and ethylene inducing-like proteins Nlp2 and Nlp3, the cerato-platanin proteins Cp1 and Cp2, the metallopeptidases Mep1 and Mep2 and the carbohydrate-active enzymes Gla1, Amy1 and Cbd1. Their pathogenicity contribution was analyzed in the haploid parental strain . Deletion of the majority of the corresponding genes caused no phenotypic changes during growth or invasion and colonization of tomato plants. However, we discovered that the , , and deletion strains were compromised in plant infections. Overall, our exoproteome approach revealed that the fungus induces specific secretion responses in different environments. The fungus has a general response to non-plant related media whereas it is able to fine-tune its exoproteome in the presence of plant material. Importantly, the xylem sap-specific exoproteome pinpointed Nlp2 and Nlp3 as single effectors required for successful colonization.
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http://dx.doi.org/10.3389/fmicb.2020.01876DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7423881PMC
August 2020

The High Osmolarity Glycerol Mitogen-Activated Protein Kinase regulates glucose catabolite repression in filamentous fungi.

PLoS Genet 2020 08 25;16(8):e1008996. Epub 2020 Aug 25.

Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Bloco Q, Universidade de São Paulo, Brazil.

The utilization of different carbon sources in filamentous fungi underlies a complex regulatory network governed by signaling events of different protein kinase pathways, including the high osmolarity glycerol (HOG) and protein kinase A (PKA) pathways. This work unraveled cross-talk events between these pathways in governing the utilization of preferred (glucose) and non-preferred (xylan, xylose) carbon sources in the reference fungus Aspergillus nidulans. An initial screening of a library of 103 non-essential protein kinase (NPK) deletion strains identified several mitogen-activated protein kinases (MAPKs) to be important for carbon catabolite repression (CCR). We selected the MAPKs Ste7, MpkB, and PbsA for further characterization and show that they are pivotal for HOG pathway activation, PKA activity, CCR via regulation of CreA cellular localization and protein accumulation, as well as for hydrolytic enzyme secretion. Protein-protein interaction studies show that Ste7, MpkB, and PbsA are part of the same protein complex that regulates CreA cellular localization in the presence of xylan and that this complex dissociates upon the addition of glucose, thus allowing CCR to proceed. Glycogen synthase kinase (GSK) A was also identified as part of this protein complex and shown to potentially phosphorylate two serine residues of the HOG MAPKK PbsA. This work shows that carbon source utilization is subject to cross-talk regulation by protein kinases of different signaling pathways. Furthermore, this study provides a model where the correct integration of PKA, HOG, and GSK signaling events are required for the utilization of different carbon sources.
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http://dx.doi.org/10.1371/journal.pgen.1008996DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7473523PMC
August 2020

Hülle Cells of Aspergillus nidulans with Nuclear Storage and Developmental Backup Functions Are Reminiscent of Multipotent Stem Cells.

mBio 2020 08 11;11(4). Epub 2020 Aug 11.

Department of Molecular Microbiology and Genetics, Georg-August-University, Göttingen, Germany

Some aspergilli are among the most cosmopolitan and ecologically dominant fungal species. One pillar of their success is their complex life cycle, which creates specialized cell types for versatile dispersal and regenesis. One of these cell types is unique to aspergilli-the Hülle cells. Despite being known for over a century, the biological and ecological roles of Hülle cells remain largely speculative. Previously reported data on Hülle cell formation and localization have been conflicting. Our quantification reveals that Hülle cells can occur at all locations on hyphae and that they show cellular activity similar to that seen with adjacent hyphae, indicating that they develop as intricate parts of hyphal tissue. In addition, we show that during sexual development associated with two parental strains, the typically multinucleate Hülle cells can inherit nuclei from both parents, indicating that they may serve as genetic backups. We provide an easy, reproducible method to study Hülle cell biology and germination with which we investigate the 90-year-old puzzle of whether and how Hülle cells germinate. We present clear evidence for the germination of Hülle cells, and we show that Hülle cells grow hyphae that develop into a spore-producing colony. Finally, we show that Hülle cell-derived colonies produce conidiospores faster than spore-derived colonies, providing evidence for an as-yet-undescribed developmental shortcut program in We propose that Hülle cells represent a unique cell type as specialized hypha-derived sexual tissue with a nucleus storage function and may act as fungal backup stem cells under highly destructive conditions. The identification of Hülle cells in cases of aspergillosis infections in animals and humans illustrates their biological relevance and suggests that they might be involved in pathogenicity. It is striking that aspergilli have developed and maintained a multinucleate nurse cell that is presumably energy-intensive to produce and is usually found only in higher eukaryotes. Our findings shed light on how the understudied Hülle cells might contribute to the success of aspergilli by acting not only as nurse cells under detrimental conditions (sexual development) but also as fungal backup stem cells with the capacity to produce genetically diverse spores in an accelerated manner, thereby substantially contributing to survival in response to predator attack or under otherwise severely destructive conditions. Our study solved the 90-year-old puzzle of Hülle cell germination and provides easy, reproducible methods that will facilitate future studies on biological and ecological roles of Hülle cells in aspergilli.
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http://dx.doi.org/10.1128/mBio.01673-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7439468PMC
August 2020

The Novel J-Domain Protein Mrj1 Is Required for Mitochondrial Respiration and Virulence in Cryptococcus neoformans.

mBio 2020 06 9;11(3). Epub 2020 Jun 9.

Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada

The opportunistic fungal pathogen must adapt to the mammalian environment to establish an infection. Proteins facilitating adaptation to novel environments, such as chaperones, may be required for virulence. In this study, we identified a novel mitochondrial co-chaperone, Mrj1 (itochondrial espiration -domain protein ), necessary for virulence in The and J-domain-inactivated mutants had general growth defects at both routine laboratory and human body temperatures and were deficient in the major virulence factor of capsule elaboration. The latter phenotype was associated with cell wall changes and increased capsular polysaccharide shedding. Accordingly, the mutant was avirulent in a murine model of cryptococcosis. Mrj1 has a mitochondrial localization and co-immunoprecipitated with Qcr2, a core component of complex III of the electron transport chain. The mutants were deficient in mitochondrial functions, including growth on alternative carbon sources, growth without iron, and mitochondrial polarization. They were also insensitive to complex III inhibitors and hypersensitive to an alternative oxidase (AOX) inhibitor, suggesting that Mrj1 functions in respiration. In support of this conclusion, mutants also had elevated basal oxygen consumption rates which were completely abolished by the addition of the AOX inhibitor, confirming that Mrj1 is required for mitochondrial respiration through complexes III and IV. Furthermore, inhibition of complex III phenocopied the capsule and cell wall defects of the mutants. Taken together, these results indicate that Mrj1 is required for normal mitochondrial respiration, a key aspect of adaptation to the host environment and virulence. is the causative agent of cryptococcal meningitis, a disease responsible for ∼15% of all HIV-related deaths. Unfortunately, development of antifungal drugs is challenging because potential targets are conserved between humans and In this context, we characterized a unique J-domain protein, Mrj1, which lacks orthologs in humans. We showed that Mrj1 was required for normal mitochondrial respiration and that mutants lacking Mrj1 were deficient in growth, capsule elaboration, and virulence. Furthermore, we were able to phenocopy the defects in growth and capsule elaboration by inhibiting respiration. This result suggests that the role of Mrj1 in mitochondrial function was responsible for the observed virulence defects and reinforces the importance of mitochondria to fungal pathogenesis. Mitochondria are difficult to target, as their function is also key to human cells; however, Mrj1 presents an opportunity to target a unique fungal protein required for mitochondrial function and virulence in .
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http://dx.doi.org/10.1128/mBio.01127-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7373193PMC
June 2020

The Vta1 transcriptional regulator is required for microsclerotia melanization in Verticillium dahliae.

Fungal Biol 2020 05 31;124(5):490-500. Epub 2020 Jan 31.

Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Göttingen and Göttingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077 Göttingen, Germany. Electronic address:

Many fungi are able to produce resting structures, which ensure survival and protect them against various stresses in their habitat such as exposure to UV light, temperature variations, drought as well as changing pH and nutrient conditions. Verticillium dahliae is a plant pathogenic fungus that forms melanized resting structures, called microsclerotia, for survival of time periods without a host. These highly stress resistant microsclerotia persist in the soil for many years and are therefore problematic for an effective treatment of the fungus. The Verticillium transcription activator of adhesion 1 (Vta1) was initially identified as one of several transcriptional regulators that rescue adhesion in non-adhesive Saccharomyces cerevisiae cells. Vta2 and Vta3 are required for early steps in plant infection and colonization and additionally control microsclerotia formation. Here, we show that Vta1 function is different, because it is dispensable for root colonization and infection. Vta1 is produced in the fungal cell during microsclerotia development. Analysis of the deletion mutant revealed that the absence of Vta1 allows microsclerotia production, but they are colorless and no more melanized. Vta1 is required for melanin production and activates transcription of melanin biosynthesis genes including the polyketide synthase encoding PKS1 and the laccase LAC1. The primary function of Vta1 in melanin production is important for survival of microsclerotia as resting structures of V. dahliae.
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http://dx.doi.org/10.1016/j.funbio.2020.01.007DOI Listing
May 2020

The Third International Symposium on Fungal Stress - ISFUS.

Fungal Biol 2020 05 24;124(5):235-252. Epub 2020 Feb 24.

Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jeruslaem, Rehovot 7610001, Israel.

Stress is a normal part of life for fungi, which can survive in environments considered inhospitable or hostile for other organisms. Due to the ability of fungi to respond to, survive in, and transform the environment, even under severe stresses, many researchers are exploring the mechanisms that enable fungi to adapt to stress. The International Symposium on Fungal Stress (ISFUS) brings together leading scientists from around the world who research fungal stress. This article discusses presentations given at the third ISFUS, held in São José dos Campos, São Paulo, Brazil in 2019, thereby summarizing the state-of-the-art knowledge on fungal stress, a field that includes microbiology, agriculture, ecology, biotechnology, medicine, and astrobiology.
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http://dx.doi.org/10.1016/j.funbio.2020.02.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7438019PMC
May 2020

Growing a circular economy with fungal biotechnology: a white paper.

Fungal Biol Biotechnol 2020 2;7. Epub 2020 Apr 2.

22Department of Biology, Microbiology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.

Fungi have the ability to transform organic materials into a rich and diverse set of useful products and provide distinct opportunities for tackling the urgent challenges before all humans. Fungal biotechnology can advance the transition from our petroleum-based economy into a bio-based circular economy and has the ability to sustainably produce resilient sources of food, feed, chemicals, fuels, textiles, and materials for construction, automotive and transportation industries, for furniture and beyond. Fungal biotechnology offers solutions for securing, stabilizing and enhancing the food supply for a growing human population, while simultaneously lowering greenhouse gas emissions. Fungal biotechnology has, thus, the potential to make a significant contribution to climate change mitigation and meeting the United Nation's sustainable development goals through the rational improvement of new and established fungal cell factories. The White Paper presented here is the result of the 2nd Think Tank meeting held by the EUROFUNG consortium in Berlin in October 2019. This paper highlights discussions on current opportunities and research challenges in fungal biotechnology and aims to inform scientists, educators, the general public, industrial stakeholders and policymakers about the current fungal biotech revolution.
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http://dx.doi.org/10.1186/s40694-020-00095-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7140391PMC
April 2020

The COP9 signalosome mediates the Spt23 regulated fatty acid desaturation and ergosterol biosynthesis.

FASEB J 2020 04 19;34(4):4870-4889. Epub 2020 Feb 19.

Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Israel.

The COP9 signalosome (CSN) is a conserved eukaryotic complex, essential for vitality in all multicellular organisms and critical for the turnover of key cellular proteins through catalytic and non-catalytic activities. Saccharomyces cerevisiae is a powerful model organism for studying fundamental aspects of the CSN complex, since it includes a conserved enzymatic core but lacks non-catalytic activities, probably explaining its non-essentiality for life. A previous transcriptomic analysis of an S. cerevisiae strain deleted in the CSN5/RRI1 gene, encoding to the CSN catalytic subunit, revealed a downregulation of genes involved in lipid metabolism. We now show that the S. cerevisiae CSN holocomplex is essential for cellular lipid homeostasis. Defects in CSN assembly or activity lead to decreased quantities of ergosterol and unsaturated fatty acids (UFA); vacuole defects; diminished lipid droplets (LDs) size; and to accumulation of endoplasmic reticulum (ER) stress. The molecular mechanism behind these findings depends on CSN involvement in upregulating mRNA expression of SPT23. Spt23 is a novel activator of lipid desaturation and ergosterol biosynthesis. Our data reveal for the first time a functional link between the CSN holocomplex and Spt23. Moreover, CSN-dependent upregulation of SPT23 transcription is necessary for the fine-tuning of lipid homeostasis and for cellular health.
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http://dx.doi.org/10.1096/fj.201902487RDOI Listing
April 2020

Corrigendum to 'Fungal S-adenosylmethionine synthetase and the control of development and secondary metabolism in Aspergillus nidulans'. [Fungal Genet. Biol. 49 (2012) 443-454].

Fungal Genet Biol 2020 Mar 10;136:103331. Epub 2020 Jan 10.

Institut für Mikrobiologie & Genetik, Georg-August-Universität, Grisebachstr. 8, D-37077 Göttingen, Germany. Electronic address:

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http://dx.doi.org/10.1016/j.fgb.2019.103331DOI Listing
March 2020

Identification of Low-Abundance Lipid Droplet Proteins in Seeds and Seedlings.

Plant Physiol 2020 03 11;182(3):1326-1345. Epub 2019 Dec 11.

University of Göttingen, Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center for Molecular Biosciences (GZMB), Department of Plant Biochemistry, 37077 Göttingen, Germany

The developmental program of seed formation, germination, and early seedling growth requires not only tight regulation of cell division and metabolism, but also concerted control of the structure and function of organelles, which relies on specific changes in their protein composition. Of particular interest is the switch from heterotrophic to photoautotrophic seedling growth, for which cytoplasmic lipid droplets (LDs) play a critical role as depots for energy-rich storage lipids. Here, we present the results of a bottom-up proteomics study analyzing the total protein fractions and LD-enriched fractions in eight different developmental phases during silique (seed) development, seed germination, and seedling establishment in Arabidopsis (). The quantitative analysis of the LD proteome using LD-enrichment factors led to the identification of six previously unidentified and comparably low-abundance LD proteins, each of which was confirmed by intracellular localization studies with fluorescent protein fusions. In addition to these advances in LD protein discovery and the potential insights provided to as yet unexplored aspects in plant LD functions, our data set allowed for a comparative analysis of the LD protein composition throughout the various developmental phases examined. Among the most notable of the alterations in the LD proteome were those during seedling establishment, indicating a switch in the physiological function(s) of LDs after greening of the cotyledons. This work highlights LDs as dynamic organelles with functions beyond lipid storage.
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http://dx.doi.org/10.1104/pp.19.01255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7054876PMC
March 2020

Broad Substrate-Specific Phosphorylation Events Are Associated With the Initial Stage of Plant Cell Wall Recognition in .

Front Microbiol 2019 1;10:2317. Epub 2019 Nov 1.

Holzforschung München, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany.

Fungal plant cell wall degradation processes are governed by complex regulatory mechanisms, allowing the organisms to adapt their metabolic program with high specificity to the available substrates. While the uptake of representative plant cell wall mono- and disaccharides is known to induce specific transcriptional and translational responses, the processes related to early signal reception and transduction remain largely unknown. A fast and reversible way of signal transmission are post-translational protein modifications, such as phosphorylations, which could initiate rapid adaptations of the fungal metabolism to a new condition. To elucidate how changes in the initial substrate recognition phase of affect the global phosphorylation pattern, phospho-proteomics was performed after a short (2 min) induction period with several plant cell wall-related mono- and disaccharides. The MS/MS-based peptide analysis revealed large-scale substrate-specific protein phosphorylation and de-phosphorylations. Using the proteins identified by MS/MS, a protein-protein-interaction (PPI) network was constructed. The variance in phosphorylation of a large number of kinases, phosphatases and transcription factors indicate the participation of many known signaling pathways, including circadian responses, two-component regulatory systems, MAP kinases as well as the cAMP-dependent and heterotrimeric G-protein pathways. Adenylate cyclase, a key component of the cAMP pathway, was identified as a potential hub for carbon source-specific differential protein interactions. In addition, four phosphorylated F-Box proteins were identified, two of which, Fbx-19 and Fbx-22, were found to be involved in carbon catabolite repression responses. Overall, these results provide unprecedented and detailed insights into a so far less well known stage of the fungal response to environmental cues and allow to better elucidate the molecular mechanisms of sensory perception and signal transduction during plant cell wall degradation.
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http://dx.doi.org/10.3389/fmicb.2019.02317DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6838226PMC
November 2019

Erratum for Gerke et al., "Breaking the Silence: Protein Stabilization Uncovers Silenced Biosynthetic Gene Clusters in the Fungus Aspergillus nidulans".

Appl Environ Microbiol 2019 Dec 14;85(23). Epub 2019 Nov 14.

Abteilung für Molekulare Mikrobiologie & Genetik, Institut für Mikrobiologie & Genetik, Georg August Universität, Göttingen, Germany

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http://dx.doi.org/10.1128/AEM.02251-19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6856330PMC
December 2019

Genome sequencing of evolved aspergilli populations reveals robust genomes, transversions in A. flavus, and sexual aberrancy in non-homologous end-joining mutants.

BMC Biol 2019 11 11;17(1):88. Epub 2019 Nov 11.

Department of Genetics, Faculty of Biology, University of Seville, Seville, Spain.

Background: Aspergillus spp. comprises a very diverse group of lower eukaryotes with a high relevance for industrial applications and clinical implications. These multinucleate species are often cultured for many generations in the laboratory, which can unknowingly propagate hidden genetic mutations. To assess the likelihood of such events, we studied the genome stability of aspergilli by using a combination of mutation accumulation (MA) lines and whole genome sequencing.

Results: We sequenced the whole genomes of 30 asexual and 10 sexual MA lines of three Aspergillus species (A. flavus, A. fumigatus and A. nidulans) and estimated that each MA line accumulated mutations for over 4000 mitoses during asexual cycles. We estimated mutation rates of 4.2 × 10 (A. flavus), 1.1 × 10 (A. fumigatus) and 4.1 × 10 (A. nidulans) per site per mitosis, suggesting that the genomes are very robust. Unexpectedly, we found a very high rate of GC → TA transversions only in A. flavus. In parallel, 30 asexual lines of the non-homologous end-joining (NHEJ) mutants of the three species were also allowed to accumulate mutations for the same number of mitoses. Sequencing of these NHEJ MA lines gave an estimated mutation rate of 5.1 × 10 (A. flavus), 2.2 × 10 (A. fumigatus) and 4.5 × 10 (A. nidulans) per base per mitosis, which is slightly higher than in the wild-type strains and some ~ 5-6 times lower than in the yeasts. Additionally, in A. nidulans, we found a NHEJ-dependent interference of the sexual cycle that is independent of the accumulation of mutations.

Conclusions: We present for the first time direct counts of the mutation rate of filamentous fungal species and find that Aspergillus genomes are very robust. Deletion of the NHEJ machinery results in a slight increase in the mutation rate, but at a rate we suggest is still safe to use for biotechnology purposes. Unexpectedly, we found GC→TA transversions predominated only in the species A. flavus, which could be generated by the hepatocarcinogen secondary metabolite aflatoxin. Lastly, a strong effect of the NHEJ mutation in self-crossing was observed and an increase in the mutations of the asexual lines was quantified.
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http://dx.doi.org/10.1186/s12915-019-0702-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6844060PMC
November 2019

Cytoplasmic retention and degradation of a mitotic inducer enable plant infection by a pathogenic fungus.

Elife 2019 10 17;8. Epub 2019 Oct 17.

Instituto de Biología Funcional y Genómica (CSIC), Salamanca, Spain.

In the fungus , sexual pheromones elicit mating resulting in an infective filament able to infect corn plants. Along this process a G2 cell cycle arrest is mandatory. Such as cell cycle arrest is initiated upon the pheromone recognition in each mating partner, and sustained once cell fusion occurred until the fungus enter the plant tissue. We describe that the initial cell cycle arrest resulted from inhibition of the nuclear transport of the mitotic inducer Cdc25 by targeting its importin, Kap123. Near cell fusion to take place, the increase on pheromone signaling promotes Cdc25 degradation, which seems to be important to ensure the maintenance of the G2 cell cycle arrest to lead the formation of the infective filament. This way, premating cell cycle arrest is linked to the subsequent steps required for establishment of the infection. Disabling this connection resulted in the inability of fungal cells to infect plants.
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http://dx.doi.org/10.7554/eLife.48943DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6887120PMC
October 2019
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