Ima Fungus最新文献

Histone deacetylases (HDACs) are key epigenetic regulators governing chromatin structure and gene expression, playing critical roles in growth, development, virulence, and multi-stress resistance of plant-pathogenic fungi. Despite their importance, the HDAC gene family (FoHDACs) in Fusarium oxysporum remains poorly characterized. Through genome-wide analysis, we identified 11 FoHDAC genes, phylogenetically classified into three subfamilies: Class I (2 genes), Class II (2 genes), and SIR2 (7 genes). Subcellular localization predicted 6 in the nucleus, 3 in the cytoplasm, and 2 in mitochondria, indicating functional diversity across organelles. Structural analyses revealed conserved domains/motifs specific to each subfamily. Genes showed asymmetric distribution across 6 chromosomes with no recent duplication events. Promoter analysis identified 22 putative cis-elements, including antioxidant (ARE, as-1) and stress response elements (STRE), linking FoHDACs to development and environmental responses. Functional annotation highlighted putative roles in transcriptional regulation, macromolecular catabolism, and heterochromatin assembly beyond core HDAC activity. Molecular docking showed binding affinities < -5 kcal/mol with significant differences across subfamilies. RT-qPCR revealed stage-specific expression: 8 genes peaked in dormant conidia, were suppressed during germination, and recovered during growth/sporulation; 2 showed continuous activation, and 1 was sporulation-specific. Abiotic stresses induced stimulus-dependent regulation, e.g., 33.67-fold repression of FoHST3 under salt stress and > 100-fold induction of FoHOS3 under cold stress. Collectively, our findings reveal that FoHDACs exhibit substantial functional diversity, forming a sophisticated regulatory network mediating fungal development and environmental adaptation.

Transitions between saprotrophic and biotrophic lifestyles represent pivotal evolutionary events in fungal ecology; however, the genomic and physiological mechanisms underlying such shifts remain poorly understood. The agaric genus Clitopilus (Basidiomycota, Entolomataceae) offers a valuable model system, with most species being soil saprotrophs. Clitopilus cf. baronii Consiglio & Setti exhibits genomic signatures suggesting incipient biotrophic capacity. Here, we investigated the genomic and eco-physiological properties of seven strains representing five Clitopilus species to identify traits associated with lifestyle transitions. ITS-based phylogeny combined with ecological metadata revealed potential facultative biotrophy in multiple taxa from the section Scyphoides. Physiological profiling showed that all strains utilized mannitol and sucrose poorly, preferred organic nitrogen compounds, and produced variable amounts of indole-3-acetic acid (IAA) in vitro in a strictly tryptophan-dependent manner. Enzymatic assays revealed substantial variations in the nitrogen and phosphorus acquisition capabilities among the strains. Comparative genomics of high-quality assemblies identified a pleuromutilin biosynthetic gene cluster (BGC) across all strains, although synteny analysis revealed considerable structural variation and putative gene loss, indicating that genomic plasticity potentially affects antibiotic production. Principal component analysis of carbohydrate-active enzymes (CAZymes) across 25 fungal genomes partitioned Clitopilus strains into two distinct groups: one resembling saprotrophic white-rot basidiomycetes, the other matching biotrophic ectomycorrhizal and endophytic taxa. This first comprehensive genomic analysis of Clitopilus revealed that nutritional specialization, phytohormone production, and CAZyme repertoire remodeling collectively signal an ongoing evolutionary transition from saprotrophy to plant-associated lifestyles in multiple lineages. These findings provide a rare genomic window into the early stages of symbiosis evolution, offering insights into how free-living fungi acquire the molecular toolkit for mutualistic partnerships.

Global increases in connectivity have greatly accelerated the frequency of biological invasions across most of Earth's ecosystems, including forests. Once invasive organisms become established in a naïve environment, they are difficult to eradicate or contain; thus, management strategies often focus on mitigating their impacts. As the use of chemical pesticides in forests is increasingly prohibited, biological control of pests and diseases has gained importance as an environmentally friendly alternative. Virus-mediated hypovirulence in the chestnut blight fungus Cryphonectria parasitica is one of the few successful examples of biological control of an invasive forest pathogen. However, experiments testing the stability of this system in situ are still missing. In this study, we conducted a field experiment in chestnut stands with naturally established hypovirulence in Switzerland, Croatia, and North Macedonia to evaluate the effectiveness of CHV1-mediated biocontrol of chestnut blight under different vegetative compatibility (vc) type population structures. Our results demonstrate that CHV1 is highly effective as a biological control agent against C. parasitica. Artificially initiated bark cankers of various vc types were rapidly infected by resident CHV1 strains, which significantly reduced canker growth and sporulation, thereby increasing the survival chances of the infected chestnut sprouts. Under field conditions, vegetative incompatibility barriers proved to be far less restrictive for virus transmission than predicted in vitro. Furthermore, our study demonstrates that the immigration of new fungal genotypes into existing cankers is an inherent component of the epidemiology of C. parasitica, which significantly contributes to the spread of CHV1. These results are particularly favourable for ensuring the success of hypovirulence-mediated biocontrol of chestnut blight in Europe. However, our conclusions cannot be automatically translated to genetically distant vc types from outside Europe, whose accidental introduction should be further avoided.

Sclerotinia is a fungal genus of significant agricultural and scientific importance, as it includes multiple plant pathogens and provides an informative case study for mechanisms of host generalism. However, the taxonomy of this group remains unsettled, which hinders research on these pathogens. The last monographic treatment of Sclerotinia was published more than 40 years ago and was centered on the morphological data available at that time. Here, we examine that revision alongside other pivotal publications to trace the taxonomic history of Sclerotinia and to evaluate the morphological traits used to identify Sclerotinia species. We also briefly assess the composition of genera in the family Sclerotiniaceae, emphasising the need for a modern taxonomic investigation of the broader group. Thirteen new Sclerotinia species have been described since the last taxonomic revision, including Sclerotinia antarctica, S. asari, S. atrostipitata, S. cirsii-spinosissimi, S. ginseng, S. glacialis, S. himalayensis, S. nivalis, S. pseudoplatani, S. subarctica, S. tetraspora, S. trillii, and S. verrucispora. These species are evaluated here. Finally, several recommendations are made regarding how future taxonomic research on Sclerotinia should incorporate molecular data. We highlight potential obstacles and opportunities for this research, including the limitations of the internal transcribed spacer rDNA region (ITS) as a DNA barcode and the untapped potential of genomic data for the genus. By outlining the gaps that need to be addressed, this review charts a course toward a clearer understanding of taxonomic relationships among Sclerotinia species. This understanding will facilitate research into other aspects, such as pathogenicity and host generalism, and may ultimately contribute to improved management of the devastating diseases caused by these pathogens.

Lophodermium, the largest genus within the family Rhytismataceae, comprises diverse plant-associated endophytes and pathogens, including species responsible for serious diseases that cause substantial economic losses. Pine trees (Pinus spp.), among the most species-rich and widely distributed conifers worldwide, serve as hosts for many Lophodermium species. In the present study, ten new species of Lophodermium are identified and described from pine needles in China, based on an integrated approach combining morphological characteristics and multi-gene phylogenetic analyses. The discovery of these new species significantly expands the known diversity of Lophodermium spp. and offers important insights into host specificity and geographic distribution. Furthermore, this work provides an essential scientific foundation for monitoring and managing Lophodermium-associated diseases in pine forests.

Panaeolus sensu lato is a group of hallucinogenic mushrooms commonly found on dung, in pasture areas, grasslands, and forests. Previous studies indicated that the Panaeolus s.l. clade (panaeo-clade) could be ranked as a family (Galeropsidaceae), pending further evidence. In this study, based on phylogenomic, multigene phylogenetic, molecular clock, and morphological analyses, the panaeo-clade is demonstrated to be a distinct family, separate from Bolbitiaceae. The taxonomic system of Galeropsidaceae is revised. The genera accepted in Galeropsidaceae are Panaeolus and Staktophyllus, whereas Crucispora and Panaeolopsis are synonymized under Panaeolus. Three subgenera are accepted in Panaeolus: subg. Bresadolomyces, subg. Panaeolina, and subg. Panaeolus. Subgenus Bresadolomyces is roughly equivalent to the traditional circumscription of subg. Copelandia but is extended to include species formerly placed in Crucispora. Subgenus Panaeolina comprises most species from China and Anellaria-like species. Subgenus Panaeolus mainly comprises the P. papilionaceus species complex and a western Asian clade represented by P. punjabensis. In this study, one new subgenus and eight new species are proposed. Species from China are documented with descriptions, photographs, and illustrations. Additionally, the psilocybin-producing traits of 14 species were tested using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS). Two species are confirmed to possess psilocybin-producing traits, namely the known species P. cinctulus and the new species P. subfoenisecii proposed in this study. The evolution of the coprophilous lifestyle and psilocybin-producing traits in Panaeolus is also discussed based on phylogenetic relationships and divergence times.

Crust-like Sebacinaceae, comprising the genera Helvellosebacina, Sebacina, and Tremelloscypha, represent the only ectomycorrhizal lineage within the Sebacinaceae family. However, species delimitation within this group remains challenging because of their cryptic lifestyles, inconspicuous morphological traits, and limited taxonomic annotation. To address these limitations, we investigated crust-like Sebacinaceae in Asia by integrating two datasets: specimen-derived (barcoding) sequence data and root-associated metabarcoding data. A high diversity of crust-like Sebacinaceae species was uncovered, most of which did not match any previously described taxa. Multigene phylogenetic analyses (ITS, LSU, and rpb2) based on basidiomata identified eleven distinct species, of which six are proposed here as new to science. In parallel, metabarcoding data revealed additional crust-like Sebacinaceae species and confirmed their ectomycorrhizal association with Pinus and Quercus species. These findings advance our understanding of crust-like Sebacinaceae diversity and ecology in previously unexplored regions.

The new genus Garciamycella is here erected to accommodate the soil-borne fungus G. chlamydospora, as well as G. cyclaminis and G. fici, based on a phylogenetic study using sequences of ITS, LSU, rpb2, and tub2. The establishment of Garciamycella has important taxonomic implications, as it helps to resolve a phylogenetically distinct lineage in the order Sordariales, a group in which the placement of numerous taxa remains uncertain. The new species G. chlamydospora was investigated for its secondary metabolite production, affording one previously undescribed papulacandin derivative (1), together with two known compounds from the same family, Mer-WF3010 (2) and papulacandin D (3). In addition, two previously undescribed metabolites, penazaphilone M (4) and cremenoic acid (5), were isolated alongside the known derivatives cremenolide (6) and aspinolide B (7). All compounds were isolated using preparative high-performance liquid chromatography (HPLC), and their chemical structures were elucidated through comprehensive 1D and 2D NMR spectroscopic analyses, in addition to high-resolution mass spectrometry (HR-MS). Antimicrobial and cytotoxic activities were assessed for all metabolites, and compounds (1-3) revealed potent antifungal activity. This research highlights how exploring novel fungal taxa can lead to the discovery of structurally unique metabolites with significant antifungal properties. It further confirms the potential of the order Sordariales as prolific producers of bioactive compounds with potential applications in the development of new antifungal agents.

Numerous severe cases of neurotoxic mushroom poisoning worldwide are caused by ibotenic acid and muscimol produced by specific species belonging to section Amanita of the genus Amanita. Recent studies have demonstrated that both toxins are produced through the ibotenic acid biosynthetic gene cluster (iboBGC) in these species. In addition to these two toxins, section Amanita is also thought to include several species producing another neurotoxic compound, muscarine. However, the taxonomic distribution and evolutionary history of these toxins within the section remain poorly understood. In this study, phylogenetic analyses based on nucleotide sequences of two loci (ITS and LSU) and five loci (ITS, LSU, RPB2, TEF1, and TUB2), together with a phylogenomic analysis using 467 single-copy genes, were conducted to reconstruct the phylogenetic framework of section Amanita. BEAST analysis was used to estimate divergence times within the section. Gene identification of the iboBGC was conducted using 25 Amanita genomes, followed by phylogenetic analyses of each ibo gene. Biochemical analysis of muscarine was performed on 31 representative species. Based on these analyses, ibo genes were detected in 21 species forming a major monophyletic clade within the section Amanita, whereas muscarine was detected in eight species that constituted a small subclade nested within this clade. Finally, our phylogenetic, phylogenomic, chemotaxonomic, and molecular dating results indicate a monophyletic distribution of the iboBGC and muscarine within the section Amanita, with independent origins approximately 28 million years ago (Mya) and 15 Mya, respectively, and no evidence of subsequent losses.

Nitrate (NO₃ ^-) and ammonium (NH₄ ⁺) are the two main forms of inorganic nitrogen (N) found in soil. Most macrofungi show a preference for specific forms of N; however, the mechanisms behind these preferences remain poorly understood. In this study, we explored the metabolic responses induced by NO₃ ^- and NH₄ ⁺ uptake and assimilation in the ascomycete Morchella importuna, a highly valued soil-grown mushroom. Through transcriptomics, proteomics and metabolomics, we demonstrated that growth on NO₃ ^- inhibited the expression and activity of NADP-glutamate dehydrogenase while increasing the expression and activity of glutamate synthase (GOGAT) and glutamate levels, underscoring the significant role of the GOGAT pathway in glutamate synthesis in NO₃ ^--grown mycelia. Furthermore, growth on NO₃ ^- results in the downregulation of proteins involved in ribosome biogenesis and RNA transport pathways, inducing a status analogous to N starvation and oxidative stress. Simultaneously, nitrate initiated metabolic alterations related to sexual morphogenesis, such as increased glutathione levels to counter oxidative stress, the upregulated expression of tyrosinase and its substrates to accelerate melanin deposition and enhanced glycosylation to supply cell-wall formation. These findings enhance our understanding of the differential response mechanisms to N sources that affect mushroom cell homeostasis.