Establishment of a genetic transformation system for cordycipitoid fungus Cordyceps chanhua.

Cordyceps chanhua is a well-known edible and medicinal mushroom with a long history of use in China, and it contains a variety of secondary metabolites with interesting bioactive ingredients. However, recent researches have mainly focused on cultivation conditions, secondary metabolite compositions and pharmacological activities of C. chanhua, the lack of an efficient and stable genetic transformation system has largely limited further research on the relationship between secondary metabolites and biosynthetic gene clusters in C. chanhua. In this study, single-factor experiments were used to compare the effects of different osmotic stabilizers, enzyme concentrations and enzyme digestion times on protoplast yield, and we found that the highest yield of 5.53 × 108 protoplasts/mL was obtained with 0.7 M mannitol, 6 mg/mL snail enzyme and 4 h of enzyme digestion time, and the regeneration rate of protoplasts was up to approximately 30% using 0.7 M mannitol as an osmotic stabilizer. On this basis, a PEG-mediated genetic transformation system of C. chanhua was successfully established for the first time, which lays the foundation for further genetic transformation of C. chanhua.

Optimizing liquid fermentation for Wolfiporia cocos: gene expression and biosynthesis of pachymic acid and mycelial biomass.

Wolfiporia cocos, a versatile fungus acclaimed for its nutritional and therapeutic benefits in Traditional Chinese Medicine, holds immense potential for pharmaceutical and industrial applications. In this study, we aimed to optimize liquid fermentation techniques and culture medium composition to maximize mycelial biomass (MB) yield, pachymic acid (PA) concentration, and overall PA production. Additionally, we investigated the molecular basis of our findings by quantifying the expression levels of genes associated with PA and MB biosynthesis using quantitative real-time polymerase chain reaction. Under the optimized fermentation conditions, significant results were achieved, with maximum MB reaching 6.68 g l-1, PA content peaking at 1.25 mg g-1, and a total PA yield of 4.76 g l-1. Notably, among the four examined genes, squalene monooxygenase, exhibited enhanced expression at 0.06 ratio under the optimized conditions. Furthermore, within the realm of carbohydrate-active enzymes, the glycoside hydrolases 16 family displayed elevated expression levels at 21 ratios, particularly during MB production. This study enhances understanding of genetic mechanism governing MB and PA production in W. cocos, highlighting the roles of squalene monooxygenase and glycoside hydrolases 16 carbohydrate-active enzymes.

Mitogenomic and Phylogenetic Analysis of the Entomopathogenic Fungus Ophiocordyceps lanpingensis and Comparative Analysis with Other Ophiocordyceps Species.

Ophiocordyceps lanpingensis (O. lanpingensis) belongs to the genus Ophiocordyceps, which is often found in Yunnan Province, China. This species is pharmacologically important for the treatment of renal disorders induced by oxidative stress and an inadequate immune response. In the present study, the mitogenome of O. lanpingensis was determined to be a circular molecule 117,560 bp in length, and to have 31% G + C content and 69% A + T content. This mitogenome comprised 82% of the whole genome that codes for significant genes. The protein-coding regions of the O. lanpingensis mitogenome, containing 24 protein-coding genes, were associated with respiratory chain complexes, such as 3 ATP-synthase complex F0 subunits (atp6, atp8, and atp9), 2 complex IV subunits/cytochrome c oxidases (cox2 and cox3), 1 complex III subunit (cob), 4 electron transport complex I subunits/NADH dehydrogenase complex subunits (nad1, nad4, nad5, and nad6), 2 ribosomal RNAs (rns, rnl), and 11 hypothetical/predicted proteins, i.e., orf609, orf495, orf815, orf47, orf150, orf147, orf292, orf127, orf349, orf452, and orf100. It was noted that all genes were positioned on the same strand. Further, 13 mitochondrial genes with respiratory chain complexes, which presented maximum similarity with other fungal species of Ophiocordyceps, were investigated. O. lanpingensis was compared with previously sequenced species within Ophiocordycepitaceae. Comparative analysis indicated that O. lanpingensis was more closely related to O. sinensis, which is one of the most remarkable and expensive herbs due to its limited availability and the fact that it is difficult to culture. Therefore, O. lanpingensis is an important medicinal resource that can be effectively used for medicinal purposes. More extensive metabolomics research is recommended for O. lanpingensis.

Hispidin in the Medicinal Fungus Protects Dopaminergic Neurons from JNK Activation-Regulated Mitochondrial-Dependent Apoptosis in an MPP+-Induced In Vitro Model of Parkinson's Disease.

Degenerative diseases of the brain include Parkinson's disease (PD), which is associated with moveable signs and is still incurable. Hispidin belongs to polyphenol and originates primarily from the medicinal fungi Inonotus and Phellinus, with distinct biological effects. In the study, MES23.5 cells were induced by 1-methyl-4-phenylpyridinium (MPP+) to build a cell model of PD in order to detect the protective effect of hispdin and to specify the underlying mechanism. Pretreatment of MES23.5 cells with 1 h of hispdin at appropriate concentrations, followed by incubation of 24 h with 2 µmol/L MPP+ to induce cell damage. MPP+ resulted in reactive oxygen species production that diminished cell viability and dopamine content. Mitochondrial dysfunction in MS23.5 cells exposed to MPP+ was observed, indicated by inhibition of activity in the mitochondrial respiratory chain complex I, the collapse of potential in mitochondrial transmembrane, and the liberation of mitochondrial cytochrome c. Enabling C-Jun N-terminal kinase (JNK), reducing Bcl-2/Bax, and enhancing caspase-9/caspase-3/PARP cleavage were also seen by MPP+ induction associated with increased DNA fragmentation. All of the events mentioned above associated with MPP+-mediated mitochondrial-dependent caspases cascades were attenuated under cells pretreatment with hispidin (20 µmol/L); similar results were obtained during cell pretreatment with pan-JNK inhibitor JNK-IN-8 (1 µmol/L) or JNK3 inhibitor SR3576 (25 µmol/L). The findings show that hispidin has neuroprotection against MPP+-induced mitochondrial dysfunction and cellular apoptosis and suggest that hispidin can be seen as an assist in preventing PD.

A novel promising neuroprotective agent: Ganoderma lucidum polysaccharide.

Nervous system diseases (NSDs) are characterized by a wide range of symptoms, a complex pathophysiology, an unclear etiology, a great deal of variation in treatment response, and lengthy therapy cycles, all of which pose considerable hurdles to clinical treatment. A traditional valuable medicine known as Ganoderma lucidum (GL) has a significant role to play in preserving health and treating diseases. Ganoderma lucidum polysaccharides (GLP) is one of the cardinal effective active ingredients of GL, which has a number of pharmacological actions, including liver protection, immune regulation, antioxidant activity, anticancer activity, antibacterial activity, and antiviral activity. Recently, studies on the structural characterization and biological functions of GLP were presented in this article to review the progress of researches about GLP on NSDs and summarize the potential mechanisms of action. These studies were anticipated to provide new research ideas for GLP as a novel promising neuroprotective agent and provide a reference for better development and utilization of GLP.

Chemical investigations and cytotoxic effects of metabolites from Antrodia camphorata against human hepatocellular carcinoma cells.

Antrodia camphorata is used as a medicinal fungus in Taiwan to treat fatigue, food intoxication, and enhance liver function. Here we identified fermented metabolic components from the mycelium of A. camphorata KH37 and explored their anti-hepatoma potentials with study models of human hepatoblastoma cell lines. Bioassay-guided fractionation of the solid fermentation powder of A. camphorata KH37 led to the isolation of one new quinonol, antroquinonol Z (1), and nine known compounds (2-10). Treatment with 10 µM antrocamols LT1 (2) or LT3 (3) reduced cell viability of HepG2 and Huh-7 cells to about 60% in 48 hours. Antroquinonol Z (1) exhibited mild cytotoxicity against Huh-7 cells in 48 and 72 hours. Interestingly, two fractions showed cytotoxicity in HepG2 and Huh-7 cells, even better than compounds isolated from these fractions. The significant cytotoxicity of partially purified samples from A. camphorata KH37 exhibited a potential for developing alternative or complementary therapeutics against hepatoma.

Mid-Infrared Spectroscopic Study of Cultivating Medicinal Fungi Ganoderma: Composition, Development, and Strain Variability of Basidiocarps.

Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy was proposed for rapid, versatile, and non-invasive screening of Ganoderma basidiocarps to assess their potential for specific applications. Fifteen species and strains of this fungus were selected for analysis, and fine sections at different parts of young and mature basidiocarps were obtained. The spectra of fungal samples showed significant differences interpreted in terms of biochemical composition using characteristic bands of proteins, polysaccharides, lipids, and triterpenoids. Obviously, for the transverse sections in trama, especially in the basal part, the most intense bands at 950-1200 cm-1 corresponded to polysaccharide vibrations, while for the superficial sections, the bands of carbonyl and aliphatic groups of triterpenoids at 1310-1470, 1550-1740, and 2850-2980 cm-1 predominated. The pilei, especially hymenium tubes, apparently contained more proteins than the bases and stipes, as evidenced by the intense bands of amide vibrations at 1648 and 1545-1550 cm-1. The specificity of the Ganoderma basidiocarp is a densely pigmented surface layer rich in triterpenoids, as proved by ATR-FTIR spectroscopy. The spectral differences corresponding to the specificity of the triterpenoid composition may indicate the prospects of individual strains and species of this genus for cultivation and further use in food, cosmetics, or medicine.

Medicinal fungus Phellinus igniarius alleviates gout in vitro by modulating TLR4/NF-kB/NLRP3 signaling.

Background: Phellinus igniarius (P. igniarius) is a valuable medicinal and edible fungus with various biological activities such as anti-inflammation, antioxidation, and immune regulation. In this study, we explored the effects of P. igniarius on a gout model in vitro. Methods: The DPPH, ABTS, and FRAP methods were combined to determine and compare the antioxidant activities of wild P. igniarius total polyphenols (WPP) and cultivated P. igniarius total polyphenols (CPP) in vitro. Spectrophotometry was used to compare the inhibitory effect of WPP and CPP on xanthine oxidase (XO) activity to evaluate anti-hyperuricemia activity in vitro. HUVECs were stimulated with monosodium urate (MSU) crystals for 24 h to establish an acute gouty inflammation model in vitro. The protective effects were compared by measuring cell viability; the contents of ICAM-1, IL-1ß, IL-6 and VCAM-1; the protein expressions of TLR4 and NLRP3; reactive oxygen species production; and the nuclear translocation of NF-κB p65. UHPLC-QE-MS technology was used to explore the potential metabolic mechanism of P. igniarius against gout. Results: WPP and CPP had strong antioxidant capacity, and the antioxidant capacity of CPP was similar to that of WPP. In a comparative experiment of xanthine oxidase activity inhibition by WPP and CPP, the IC50 values were 88.19 µg/ml and 108.0 µg/ml, respectively. At a dose of 40 µg/ml, WPP and CPP significantly improved the decrease in cell viability induced by monosodium urate (150 µg/ml) and inhibited the increase in inflammatory factors such as ICAM-1, IL-1ß, IL-6, and VCAM-1. The increase in TLR4 and NLRP3 protein expression induced by MSU crystals in HUVECs was also significantly inhibited by total polyphenols from wild and cultivated P. igniarius. In addition, both significantly improved MSU-induced ROS overproduction and NF-κB p65 nuclear translocation. WPP and CPP may primarily be involved in phenylalanine metabolism and lysophosphatidylcholine metabolism in their role in the treatment of gout. Conclusion: CPP and WPP both showed good antioxidant activity and xanthine oxidase inhibitory activity and had good therapeutic effects on the gout model in vitro. Furthermore, this study indicated that cultivated P. igniarius had a protective effect similar to that of wild P. igniarius, which would be expected to improve the shortage of wild P. igniarius and promote the development of the cultivated P. igniarius industry and product development.

Research progress of Auricularia heimuer on cultivation physiology and molecular biology.

Auricularia heimuer (A. heimuer F. Wu, B. K. Cui, Y. C. Dai), a well-known gelatinous fungus used for both food and medicine, is a major edible fungus with a more than 1000-year history of cultivation in China. The nutrients of A. heimuer are abundant, including polysaccharides, melanin, mineral elements, etc. The A. heimuer polysaccharides exhibit antioxidant, immunomodulatory, and anticancer properties. A. heimuer is a completely different species grown in China, unlike Auricularia auricula-judae (Bull.) Quel, which was used to characterize it. The cultivated strain varies based on the local climatic factors and cultivation practices. Hardwood chips are the primary material utilized in the cultivation of substitute materials, which is the principal cultivation technique. However, in actual production, straw is frequently replaced for some wood chips to address the issue of a lack of wood. There are three different types of growing techniques: open-air ground cultivation, arch cultivation, and shed-type hanging substitute cultivation of these three, the quality of A. heimuer grown in a shed is superior to that grown in an open-air environment. The A. heimuer genome sequencing project started later than expected, and the entire genome sequencing was not finished until 2019. A. heimuer's molecular biology studies have mostly concentrated on analyzing genetic diversity and identifying cultivars using molecular markers including RAPD, ISSR, and ITS. There have only been a small number of studies on the function of A. heimuer genes, which have only focused on the preliminary cloning and expression study of a few genes, including the laccase gene and the triterpene compound production gene, among others. However, there is still a lack of comprehensive information concerning A. heimuer, necessitating a synopsis. To our knowledge, this is the first published review of A. heimuer, and it summarizes the most recent studies on its molecular biology and cultivation. This review can serve as a guide for future research on the fungus.

Electric Cell-Substrate Impedance Sensing (ECIS) as a Convenient Tool to Assess the Potential of Low Molecular Fraction Derived from Medicinal Fungus Cerrena unicolor in Action on L929 and CT-26 Cell Lines.

The increase in the incidence of cancer has contributed to the search for new therapeutic methods. In recent years, the use of preparations of natural origin from medical fungi has increased. One such active substance is the extracellular, low molecular active fraction obtained from the medicinal fungus Cerrena unicolor. This study aimed to monitor the pharmacokinetics of different concentrations of substances isolated from the medicinal fungus Cerrena unicolor (ex-LMS) using the ECIS technique. In the study, mouse L929 fibroblasts and colon cancer CT26 cell lines were treated with different concentrations of the active fractions obtained from Cerrena unicolor: C1 = 2.285 (µg/mL); C2 = 22.85 (µg/mL); and C3 = 228.5 (µg/mL). This study demonstrated that the tested preparation from Cerrena unicolor had no considerable effect on the resistance, capacitance, and impedance of L929 fibroblast cells, which was an indicator of no significant effect on its physiological processes. At the same time, those parameters exhibited a decrease in colon cancer cell viability. Following our previous and current studies on Cerrena unicolor, ex-LMS extracts can be safely used in anticancer therapy or chemoprevention with no significant harmful effects on normal cells.

Genome editing in the edible fungus Poria cocos using CRISPR-Cas9 system integrating genome-wide off-target prediction and detection.

Poria cocos is an important edible and medicinal fungus with a long history. However, the lack of adequate genetic tools has hindered molecular genetic research and the genetic modification of this species. In this study, the endogenous U6 promoters were identified by mining data from the P. cocos genome, and the promoter sequence was used to construct a sgRNA expression vector pFC332-PcU6. Then, the protoplast isolation protocol was developed, and the sgRNA-Cas9 vector was successfully transformed into the cells of P. cocos via PEG/CaCl2-mediated transformation approach. Off-target sites were genome-widely predicted and detected. As a result, the target marker gene ura3 was successfully disrupted by the CRISPR-Cas9 system. This is the first report of genome editing in P. cocos using CRISPR-Cas9 system integrating genome-wide off-target prediction and detection. These data will open up new avenues for the investigation of genetic breeding and commercial production of edible and medicinal fungus.

Genomic Sequence and Transcriptome Analysis of the Medicinal Fungus Keithomyces neogunnii.

The filamentous fungus Keithomyces neogunnii can infect the larvae of Lepidoptera (Hepialus sp.) and form an insect-fungi complex, which is utilized as an important traditional Chinese medicine. As a valuable medicinal fungus, K. neogunnii produces diverse bioactive substances (e.g., polysaccharide, vitamins, cordycepic acid, and adenosine) under cultivation conditions. Herein, we report the first high-quality genome of the K. neogunnii single-spore isolate Cg7.2a using single-molecule real-time sequencing technology in combination with Illumina sequencing. The assembled genome was 32.6 Mb in size, containing 8,641 predicted genes and having a GC content of 52.16%. RNA sequencing analysis revealed the maximum number of differentially expressed genes in the fungus during the stroma formation stage compared with those during the mycelium stage. These data are valuable to enhance our understanding of the biology, development, evolution, and physiological metabolism of K. neogunnii.

Influence of selenium on the mycelia of the shaggy bracket fungus, Inonotus hispidus.

BACKGROUND: Selenium (Se) is a needed trace element for animals and humans. Many fungi have effective mechanisms to acquire, transform and accumulate Se in organic form. In this study, the effects of inorganic Se (sodium selenite) on the medicinal fungus Inonotus hispidus was investigated. RESULTS: Inonotus hispidus was capable of tolerating up to 3.85 mmol L-1 selenite, at which ~85% growth inhibition was seen, with 50% growth inhibition occurring at ~1 mmol L-1 selenite. Growth in 0.29 mmol L-1 Se resulted in I. hispidus mycelium with 115 times higher Se levels compared to growth in standard media, and an organic Se content of 86% to total Se content. The influence of Se accumulation on morphological features of I. hispidus were examined by microscopic and scanning electron microscopic observation. These data revealed significant shrinkage and deformations of I. hispidus hyphae with decreased branching and collapse of clamp connections under higher Se stress. However, conidial production in I. hispidus increased dramatically. The influence of Se on mycelial growth could be recovered by reinoculation in standard media. Se accumulation had only minimal impacts on the yield of the potential selenocompounds such as amino acids, proteins and polysaccharides. By contrast, Se-enriched I. hispidus mycelium was of higher quality due to reduction in crude fat and total ash contents. CONCLUSIONS: These data provide basic and applied information on the feasibility of producing selenized I. hispidus as an enriched and better quality product. © 2021 Society of Chemical Industry.

Immune regulatory functions of biologically active proteins from edible fungi.

Proteins from edible mushrooms have a variety of biological activities. Here, thirteen precious edible mushrooms such as Ophiocordyceps sinensis, Ganoderma lucidum, and Morchella esculenta and nine common edible mushrooms such as Flammulina velutipes, Pleurotus ostreatus, and Pleurotus eryngii, etc., from which their proteins were extracted, their composition analyzed and their immunomodulatory activity assessed. Rare mushrooms are a species of edible mushrooms with higher edible value and medicinal value than common edible mushrooms. The results showed that all the different edible mushroom crude proteins increased the proliferation and phagocytosis of mouse macrophages, and we found that these edible mushroom proteins affected the secretion of reactive oxygen species and nitric oxide by mouse macrophages. Further studies on cytokines secreted by mouse macrophages showed a significant increase in pro-inflammatory cytokines, suggesting that edible mushroom proteins promote the polarisation of macrophages into classical M1-type macrophages, further demonstrating that edible mushroom proteins enhance immunity. It was also found that the immunomodulatory activity of the precious edible mushroom proteins was significantly higher than that of the common edible mushroom proteins. These results have important implications for the processing and product development of edible mushroom proteins.

Classification, structure and mechanism of antiviral polysaccharides derived from edible and medicinal fungus.

The deficiency of chemical-synthesized antiviral drugs when applied in clinical therapy, such as drug resistance, and the lack of effective antiviral drugs to treat some newly emerging virus infections, such as COVID-19, promote the demand of novelty and safety anti-virus drug candidate from natural functional ingredient. Numerous studies have shown that some polysaccharides sourcing from edible and medicinal fungus (EMFs) exert direct or indirect anti-viral capacities. However, the internal connection of fungus type, polysaccharides structural characteristics, action mechanism was still unclear. Herein, our review focus on the two aspects, on the one hand, we discussed the type of anti-viral EMFs and the structural characteristics of polysaccharides to clarify the structure-activity relationship, on the other hand, the directly or indirectly antiviral mechanism of EMFs polysaccharides, including virus function suppression, immune-modulatory activity, anti-inflammatory activity, regulation of population balance of gut microbiota have been concluded to provide a comprehensive theory basis for better clinical utilization of EMFs polysaccharides as anti-viral agents.

Genome sequence and transcriptome profiles of pathogenic fungus Paecilomyces penicillatus reveal its interactions with edible fungus Morchella importuna.

Paecilomyces penicillatus is one of the pathogens of morels, which greatly affects the yield and quality of Morchella spp.. In the present study, we de novo assembled the genome sequence of the fungus P. penicillatus SAAS_ppe1. We analyzed the transcriptional profile of P. penicillatus SAAS_ppe1 infection of Morchella importuna at different stages (3 days and 6 days after infection) and the response of M. importuna using the transcriptome. The assembled genome sequence of P. penicillatus SAAS_ppe1 was 39.78 Mb in length (11 scaffolds; scaffold N50, 6.50 Mb), in which 99.7% of the expected genes were detected. A total of 7.48% and 19.83% clean transcriptional reads from the infected sites were mapped to the P. penicillatus genome at the early and late stages of infection, respectively. There were 3,943 genes differently expressed in P. penicillatus at different stages of infection, of which 24 genes had increased expression with the infection and infection stage, including diphthamide biosynthesis, aldehyde reductase, and NAD (P)H-hydrate epimerase (P < 0.05). Several genes had variable expression trends at different stages of infection, indicating P. penicillatus had diverse regulation patterns to infect M. importuna. GO function, involving cellular components, and KEGG pathways, involving glycerolipid metabolism, and plant-pathogen interaction were significantly enriched during infection by P. penicillatus. The expression of ten genes in M. importuna increased during the infection and infection stage, and these may regulate the response of M. importuna to P. penicillatus infection. This is the first comprehensive study on P. penicillatus infection mechanism and M. importuna response mechanism, which will lay a foundation for understanding the fungus-fungus interactions, gene functions, and variety breeding of pathogenic and edible fungi.

Structure and immunostimulating activity of a galactofuranose-rich polysaccharide from the bamboo parasite medicinal fungus Shiraia bambusicola.

ETHNOPHARMACOLOGICAL RELEVANCE: Shiraia bambusicola is a parasitic fungus on the twigs of bamboos. Its relatively large stroma has high medicinal value and can treat a variety of diseases such as rheumatoid arthritis, cold stomach pain, sciatica, injuries, chronic bronchitis, and infantile. It is widely distributed in many provinces in Southern China and also is also found in Japan. AIM OF THE STUDY: Medicinal fungi were important resources for bioactive polysaccharides. To explore bioactive polysaccharides from Shiraia bambusicola, a heteropolysaccharide SB2-1 was purified and obtained from S. bambusicola and its immunostimulating activity was researched. MATERIALS AND METHODS: The polysaccharide from S. bambusicola was extracted and purified using enzyme assisted extraction, ethanol precipitation, anion-exchange and size-exclusion chromatography. Molecular weight of polysaccharide was estimated by high performance gel permeation chromatography. Monosaccharide compositions were determined by high performance liquid chromatography after pre-column derivatization and UV detection. Structure information was elucidated by IR spectrum, GC-MS analysis after methylation and gradual acid hydrolysis of the polysaccharide. The RAW264.7 cells were used to study the immunostimulating activity in vitro. RESULTS: Physicochemical and structural analyses showed that SB2-1 was a neutral heteropolysaccharide with molecular weight at 22.2 kDa and consisted of glucose, galactose and mannose at a ratio of 2.0:1.5:1.0. The structure of SB2-1 was a branched polysaccharides composed of a mannan core and side chains consisted of glucose and galactose. The mannan core was composed of (1→2)-Manp as the main chain. Glucose with (1→4)-D-Glcp, (1→2)-D-Glcp and (1→6)-D-Glcp at different degrees of polymerization were linked at C-6 and C-3 of the (1→2)-Manp as the side chains. The galactose with the linages of (1→6)-D-Galf, →2)-D-Galf(1→ and terminal D-Galf(1→ also existed in the side chain. The study on the immunostimulating activities of SB2-1 and its core structure P-2 were investigated on RAW264.7 macrophages. The results showed that SB2-1 could activate RAW264.7 macrophage and significantly improve its phagocytic ability by neutral red uptake experiment. Meanwhile, SB2-1 increased significantly higher inducible nitric oxide synthase (iNOS) production and the productions of IL-1, IL-6, IL-12 and TNF-α. The effect of SB2-1 was better than its core structure P-2 produced by gradual acid hydrolysis, which meant the side chains played an important role in the immunostimulating activities. CONCLUSIONS: The investigation demonstrated that the galactofuranose-containing mannogalactoglucan was characteristic polysaccharides in S. bambusicola and could enhance the activation of macrophages.

Comparative transcriptome analysis revealed genes involved in the fruiting body development of Ophiocordyceps sinensis.

Ophiocordyceps sinensis is a highly valued fungus that has been used as traditional Asian medicine. This fungus is one of the most important sources of income for the nomadic populations of the Tibetan Plateau. With global warming and excessive collection, the wild O. sinensis resources declined dramatically. The cultivation of O. sinensis hasn't been fully operational due to the unclear genetic basis of the fruiting body development. Here, our study conducted pairwise comparisons between transcriptomes acquired from different growth stages of O. sinensis including asexual mycelium (CM), developing fruiting body (DF) and mature fruiting body (FB). All RNA-Seq reads were aligned to the genome of O. sinensis CO18 prior to comparative analyses. Cluster analysis showed that the expression profiles of FB and DF were highly similar compared to CM. Alternative splicing analysis (AS) revealed that the stage-specific splicing genes may have important functions in the development of fruiting body. Functional enrichment analyses showed that differentially expressed genes (DEGs) were enriched in protein synthesis and baseline metabolism during fruiting body development, indicating that more protein and energy might be required for fruiting body development. In addition, some fruiting body development-associated genes impacted by ecological factors were up-regulated in FB samples, such as the nucleoside diphosphate kinase gene (ndk), ß subunit of the fatty acid synthase gene (cel-2) and the superoxide dismutase gene (sod). Moreover, the expression levels of several cytoskeletons genes were significantly altered during all these growth stages, suggesting that these genes play crucial roles in both vegetative growth and the fruiting body development. Quantitative PCR (qPCR) was used to validate the gene expression profile and the results supported the accuracy of the RNA-Seq and DEGs analysis. Our study offers a novel perspective to understand the underlying growth stage-specific molecular differences and the biology of O. sinensis fruiting body development.

Hetero-biosynthesis of the main bioactive components from medicinal fungus Shiraia bambusiccola / 药学学报

italic>Shiraia bambusiccola is an important medicinal fungus in China. Hypocrellins with perylenequinone skeleton are main bioactive components of Shiraia bambusiccola, which are widely used in food, medicine, pesticide and other fields as natural photosensitizers. For example, "hypocrellin ointment" has already been used clinically. As a rare and vulnerable species, wild Shiraia bambusiccola resources are very limited. Due to the complex structure and chanllenge in chemical total synthesis of hypocrellins, it is urgent to find an effective strategy to rationally utilize its medicinal value while protecting the wild resources. In this study, a candidate gene cluster hpc was identified in Shiraia sp. cfcc 84681 based on careful bioinformatic analysis. A heterologous expression system for hpc gene cluster was successfully constructed and a mutant strain with high yield of hypocrellins was obtained, which mainly produced hypocrellin A and isohypocrellin A. The main ingredients in the mutant strain are consistent with that in the wild Shiraia bambusiccola. These results provide a new strategy to solve the shortage of wild Shiraia bambusiccola resources.

Whole genome sequence of Auricularia heimuer (Basidiomycota, Fungi), the third most important cultivated mushroom worldwide.

Heimuer, Auricularia heimuer, is one of the most famous traditional Chinese foods and medicines, and it is the third most important cultivated mushroom worldwide. The aim of this study is to develop genomic resources for A. heimuer to furnish tools that can be used to study its secondary metabolite production capability, wood degradation ability and biosynthesis of polysaccharides. The genome was obtained from single spore mycelia of the strain Dai 13782 by using combined high-throughput Illumina HiSeq 4000 system with the PacBio RSII long-read sequencing platform. Functional annotation was accomplished by blasting protein sequences with different public available databases to obtain their corresponding annotations. It is 49.76Mb in size with a N50 scaffold size of 1,350,668bp and encodes 16,244 putative predicted genes. This is the first genome-scale assembly and annotation for A. heimuer, which is the third sequenced species in Auricularia.