The secretory protein COA1 enables Metarhizium robertsii to evade insect immune recognition during cuticle penetration.

The interplay between the insect immune system and entomopathogenic fungi during cuticle penetration is not yet fully understood. Here, we show that a secretory protein COA1 (coat of appressorium 1) from Metarhizium robertsii, an entomopathogenic fungus causing diseases in a wide range of insects, is required to avoid host immune recognition during cuticle penetration. COA1 is highly expressed on the cuticle and translocated to the cell surface, where it directly binds with and masks carbohydrates of the fungal cell wall to avoid provoking the host's intense immune response.

Histone deacetylase HDAC3 regulates ergosterol production for oxidative stress tolerance in the entomopathogenic and endophytic fungus .

Oxidative stress is encountered by fungi in almost all niches, resulting in fungal degeneration or even death. Fungal tolerance to oxidative stress has been extensively studied, but the current understanding of the mechanisms regulating oxidative stress tolerance in fungi remains limited. The entomopathogenic and endophytic fungus encounters oxidative stress when it infects insects and develops a symbiotic relationship with plants, and we found that host reactive oxygen species (ROSs) greatly limited fungal growth in both insects and plants.

Enhancing heterogeneous Fenton-like catalysis through pyrrolidine modification of FeO-CuO composites with oxygen-vacancy defects.

Enhancing the generation of reactive hydroxyl radicals (•OH) is crucial for overcoming the limitations of the low reactivity of heterogeneous Fenton Fe-based catalysts. Researchers have explored various methods to modify catalyst structures to enhance reactivity, yet often at the expense of stability. Herein, suitable carbon and nitrogen-codoped FeO-CuO composites were synthesized via pyrolysis method, demonstrating high Fenton reaction activity and remarkable stability.

A recombinant fungal photolyase autonomously enters human cell nuclei to fix UV-induced DNA lesions.

Solar ultraviolet radiations induced DNA damages in human skin cells with cyclobutane pyrimidine dimers (CPD) and (6-4) photoproducts (6-4PPs) as the most frequent lesions. CPDs are repaired much slower than 6-4PPs by the nucleotide excision repair pathway, which are thus the major lesions that interfere with key cellular processes and give rise to gene mutations, possibly resulting in skin cancer. In prokaryotes and multicellular eukaryotes other than placental mammals, CPDs can be rapidly repaired by CPD photolyases in one simple enzymatic reaction using the energy of blue light.

Utilization of plant-derived sugars and lipids are coupled during colonization of rhizoplane and rhizosphere by the fungus Metarhizium robertsii.

Plant-derived sugars and lipids are key nutritional sources for plant associated fungi. However, the relationship between utilization of host-derived sugars and lipids during development of the symbiotic association remains unknown. Here we show that the fungus Metarhizium robertsii also needs plant-derived lipids to develop symbiotic relationship with plants.

Air Combat Intention Recognition with Incomplete Information Based on Decision Tree and GRU Network.

Battlefield information is generally incomplete, uncertain, or deceptive. To realize enemy intention recognition in an uncertain and incomplete air combat information environment, a novel intention recognition method is proposed. After repairing the missing state data of an enemy fighter, the gated recurrent unit (GRU) network, supplemented by the highest frequency method (HFM), is used to predict the future state of enemy fighter.

Bioremediation of mercury-polluted soil and water by the plant symbiotic fungus .

Fungi are central to every terrestrial and many aquatic ecosystems, but the mechanisms underlying fungal tolerance to mercury, a global pollutant, remain unknown. Here, we show that the plant symbiotic fungus degrades methylmercury and reduces divalent mercury, decreasing mercury accumulation in plants and greatly increasing their growth in contaminated soils. does this by demethylating methylmercury via a methylmercury demethylase (MMD) and using a mercury ion reductase (MIR) to reduce divalent mercury to volatile elemental mercury.

Enhanced Cd efflux capacity and physiological stress resistance: The beneficial modulations of Metarhizium robertsii on plants under cadmium stress.

Due to the high migration capacity in agricultural soil-crop systems, cadmium (Cd) is accumulated in various crops and severely inhibits plant growth. In this study, we showed that, under Cd stress, the plant-symbiotic fungus Metarhizium robertsii reduced Cd accumulation in Arabidopsis thaliana shoots and roots by 21.8 % and 23.

Metarhizium robertsii as a promising microbial agent for rice in situ cadmium reduction and plant growth promotion.

The toxic chemical element cadmium (Cd) in paddy fields triggered increasing problems of growth inhibition and food security in rice consistently. In this study, we found Metarhizium robertsii, which is widely used as a bioinsecticide and biofertilizer in agriculture and recently found to be resistant to Cd, developed intraradical and extraradical symbiotic hyphae in rice seedlings, and successfully colonized in the rice rhizosphere soil to more than 10 CFUs g soil at harvesting. M.

New Downstream Signaling Branches of the Mitogen-Activated Protein Kinase Cascades Identified in the Insect Pathogenic and Plant Symbiotic Fungus .

Fungi rely on major signaling pathways such as the MAPK (Mitogen-Activated Protein Kinase) signaling pathways to regulate their responses to fluctuating environmental conditions, which is vital for fungi to persist in the environment. The cosmopolitan fungi have multiple lifestyles and remarkable stress tolerance. Some species, especially , are emerging models for investigating the mechanisms underlying ecological adaptation in fungi.

An inactivating mutation in the vacuolar arginine exporter gene Vae results in culture degeneration in the fungus Metarhizium robertsii.

Culture degeneration usually results in great commercial losses in the economically important filamentous fungi, but the genetic causes of the degeneration remain elusive. In the fungus Metarhizium robertsii, we found that deletion of the vacuolar arginine exporter gene Vae caused culture degeneration. Compared to the WT strain, the mutant showed increased apoptosis, reactive oxygen species (ROS) level and mitochondrial membrane potential collapse, reduced conidial yield and abnormal lipid droplet formation.

Slt2-MAPK/RNS1 Controls Conidiation via Direct Regulation of the Central Regulatory Pathway in the Fungus .

Ascomycete fungi usually produce small hydrophobic asexual conidia that are easily dispersed and essential for long-term survival under a variety of environmental conditions. Several upstream signaling regulators have been documented to control conidiation via regulation of the central regulatory pathway that contains the transcription factors BrlA, AbaA and WetA. Here, we showed that the Slt2-MAPK signaling pathway and the transcription factor RNS1 constitute a novel upstream signaling cascade that activates the central regulatory pathway for conidiation in the Ascomycetes fungus .

The Sugar Transporter MST1 Is Involved in Colonization of Rhizosphere and Rhizoplane by Metarhizium .

It is widely recognized that plant-symbiotic fungi are supported by photosynthates; however, little is known about the molecular mechanisms underlying the utilization of plant-derived sugars by rhizospheric fungi. In the insect-pathogenic and plant-symbiotic fungus Metarhizium robertsii, we previously showed that the utilization of oligosaccharides by the transporter MRT ( raffinose transporter) is important for rhizosphere competency. In this study, we identified a novel monosaccharide transporter (MST1) that is involved in the colonization of the rhizoplane and acts additively with MRT to colonize the rhizosphere.

Transcriptional Differences Guided Discovery and Genetic Identification of Coprogen and Dimerumic Acid Siderophores in .

Siderophores are small molecular iron chelators and participate in the multiple cellular processes in fungi. In this study, biosynthesis gene clusters of coprogens and dimerumic acids were identified by transcriptional level differences of genes related to iron deficiency conditions in . This leads to the characterization of new coprogen metachelin C () and five known siderophores metachelin A (), metachelin A-CE (), metachelin B (), dimerumic acid 11-mannoside (), and dimerumic acid ().

A novel cascade allows Metarhizium robertsii to distinguish cuticle and hemocoel microenvironments during infection of insects.

Pathogenic fungi precisely respond to dynamic microenvironments during infection, but the underlying mechanisms are not well understood. The insect pathogenic fungus Metarhizium robertsii is a representative fungus in which to study broad themes of fungal pathogenicity as it resembles some major plant and mammalian pathogenic fungi in its pathogenesis. Here we report on a novel cascade that regulates response of M.

A Novel Nitrogen and Carbon Metabolism Regulatory Cascade Is Implicated in Entomopathogenicity of the Fungus Metarhizium robertsii.

The entomopathogenic fungus Metarhizium robertsii can switch among parasitic, saprophytic, and symbiotic lifestyles in response to changing nutritional conditions, which is attributed to its extremely versatile metabolism. Here, we found that the Fus3-mitogen-activated protein kinase (MAPK) and the transcription factor regulator of nutrient selection 1 (RNS1) constitute a novel fungal cascade that regulates the degradation of insect cuticular lipids, proteins, and chitin to obtain nutrients for hyphal growth and enter the insect hemocoel for subsequent colonization. On the insect cuticle, Fus3-MAPK physically contacts and phosphorylates RNS1, which facilitates the entry of RNS1 into nuclei.

Plant volatile organic compound (E)-2-hexenal facilitates Botrytis cinerea infection of fruits by inducing sulfate assimilation.

Investigation into plant-fungal pathogen interactions is one of the most interesting fields in plant sciences. However, the roles of plant volatile organic compounds in the arms race are still largely unknown. Based on precise quantification of plant volatiles, we discovered that the plant volatile organic compound (E)-2-hexenal, at concentrations that were similar to or lower than those in tissues of strawberry and tomato fruits, upregulates sulfate assimilation in spores and hyphae of the phytopathogenic fungus Botrytis cinerea.

Two-stage inventory management with financing under demand updates.

Considered is a retailer (she) facing non-stationary stochastic demand. Demand can be fully observed and backlogged, consequently the retailer can update the initial demand information using a Bayesian approach. To alleviate the demand risk, the retailer may use a secondary opportunity to replenish through an option contract.

Metarhizium robertsii ammonium permeases (MepC and Mep2) contribute to rhizoplane colonization and modulates the transfer of insect derived nitrogen to plants.

The endophytic insect pathogenic fungi (EIPF) Metarhizium promotes plant growth through symbiotic association and the transfer of insect-derived nitrogen. However, little is known about the genes involved in this association and the transfer of nitrogen. In this study, we assessed the involvement of six Metarhizium robertsii genes in endophytic, rhizoplane and rhizospheric colonization with barley roots.

Unveiling the Mechanisms for the Plant Volatile Organic Compound Linalool To Control Gray Mold on Strawberry Fruits.

Fungal infections significantly alter the emissions of volatile organic compounds (VOCs) by plants, but the mechanisms for VOCs affecting fungal infections of plants remain largely unknown. Here, we found that infection by upregulated linalool production by strawberries and fumigation with linalool was able to inhibit the infection of fruits by the fungus. Linalool treatment downregulated the expression of rate-limiting enzymes in the ergosterol biosynthesis pathway, and this reduced the ergosterol content in the fungi cell membrane and impaired membrane integrity.

MrSt12 implicated in the regulation of transcription factor AFTF1 by Fus3-MAPK during cuticle penetration by the entomopathogenic fungus Metarhizium robertsii.

Metarhizium robertsii is a versatile fungus with multifactorial lifestyles, and it is an emerging fungal model for investigating the mechanisms of multiple lifestyle transitions that involve trans-kingdom host jumping. Penetration of the insect cuticle is the necessary step for the transition from saprophytic or symbiotic to pathogenic lifestyle. Previously, we found the transcription factor AFTF1 plays an important role in cuticle penetration, which is precisely regulated by Fus3-MAPK, Slt2-MAPK, and the membrane protein Mr-OPY2.

Increasing Pyruvate Concentration Enhances Conidial Thermotolerance in the Entomopathogenic Fungus .

The fungal entomopathogens spp. have been developed as environmentally friendly mycoinsecticides. However, heat stress severely reduces the viability of conidia in the field, which is an important obstacle to the successful use of these mycoinsecticides.

Horizontal gene transfer allowed the emergence of broad host range entomopathogens.

The emergence of new pathogenic fungi has profoundly impacted global biota, but the underlying mechanisms behind host shifts remain largely unknown. The endophytic insect pathogen evolved from fungi that were plant associates, and entomopathogenicity is a more recently acquired adaptation. Here we report that the broad host-range entomopathogen has 18 genes that are derived via horizontal gene transfer (HGT).

Duplication of a Pks gene cluster and subsequent functional diversification facilitate environmental adaptation in Metarhizium species.

The ecological importance of the duplication and diversification of gene clusters that synthesize secondary metabolites in fungi remains poorly understood. Here, we demonstrated that the duplication and subsequent diversification of a gene cluster produced two polyketide synthase gene clusters in the cosmopolitan fungal genus Metarhizium. Diversification occurred in the promoter regions and the exon-intron structures of the two Pks paralogs (Pks1 and Pks2).