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Background: Endophytic fungi are essential members of the plant microbial community, which play a vital role in promoting plant growth and development, and inducing disease resistance. However, little is known about the ecological mechanisms of endophytic fungi impacting the root microbiota community to improve crop health. Results: An endophytic fungus Acrocalymma vagum (Code A21) isolated from wild rice enhanced rice yield by 5.73% and induced resistance against rice blast with 83.24% control efficiency in the field. The root microbiota community variations were discovered through 16S and ITS metabarcoding methods. A. vagum simplified the complexity of the rice microbiome community, reducing the proportion of the dominant pathogens Burkholderia and Ralstonia, and driving rice to recruit beneficial bacteria (Aquabacterium, Flavobacterium, and Lactobacillus) and fungi (Rhizophagus, Sarocladium, and Nigrospora). The recruited microbes were enriched in nutrient synthesis and stress resistance, especially biosynthesis of lactate, vitamin B12, and thiazole. We further isolated and identified 279 bacteria and 82 fungi from the A. vagum-fertilized rice roots to confirm the probiotic's functions. Among them, 5 Lactobacillus strains and 2 Nigrospora strains possessed significantly inhibitive activity on rice blast pathogen Magnaporthe oryzae. Additionally, 3 fungal strains in Sarocladium and Nigrospora genera promoted rice growth. Mutualistic mechanisms of A. vagum-rice were uncovered by the LC-MS/MS-based label-free quantitative assay. 13 secretory proteins of A. vagum cooperated to evade the host immune response and stimulate the symbiont resistance, such as alkaline phosphatases (ALP) as specific marker enzymes to symbiosis with the host and glycoside hydrolases (GHs) as effectors to colonize the host. Correspondingly, 206 rice proteins were induced to up-regulate, especially families of peroxidase (OsPRX), copper transporter (OsCOPT), and glutathione S-transferase (OsGSTU) related to growth and stress resistance. Conclusion: Our study verified that endophytic fungi isolated from wild rice had great practical value on cultivated rice. A. vagum reshaped the microbiota community of cultivated rice by enhancing host traits, as the first report of simplification and optimization effect of endophytic fungi on plant recruiting microbes, which offers novel perspectives on using endophytic fungi to increase agricultural productivity.

The forkhead box O3a protein (FoxO3a) has been reported to regulate tumour invasion and migration, but little is known about the molecular mechanism or its role in trophoblast invasion and migration into the uterus. In this study, we aim to explore its role in trophoblast development and placenta‐related pregnancy complications and the potential mechanism. Levels of FoxO3a and its phosphorylated form (p‐FoxO3a) in placental tissue from healthy pregnant women and pre‐eclampsia patients were first compared. Then, HTR‐8/SVneo cells were transfected with lentiviral vectors to deplete and overexpress FoxO3a. Western blot, immunohistochemistry, Cell Counting Kit‐8, wound‐healing assay, Matrigel invasion assay, cell apoptosis, cell cycle assay, RNA sequencing, qRT‐PCR and ChIP‐qPCR were performed on the cells to study the potential role of FoxO3a and the underlying mechanism. We found the expression of FoxO3a was decreased, whereas p‐FoxO3a was increased in pre‐eclampsia placentae. FoxO3a depletion significantly reduced transcription of the promoter region of intercellular cell adhesion molecule‐1 (ICAM1) gene in ChIP assays and led to reduced invasion and migration of trophoblast cells, arrested cell cycle in G1 phase and increased apoptosis under oxidative stress. Our results suggested that FoxO3a may play a role in the regulation of trophoblast invasion and migration during placental development, which may be because of its affinity to the ICAM1 promotor.

Wild rice (

Falciphora oryzae is a dark septate endophyte (DSE) isolated from wild rice roots (Oryza sativa L.). It was classified as a non-clavicitaceous endophyte. The fungus colonizes rice roots, showing a significant increase in agronomic parameters with plant biomass, rice blast resistance, yield, and quality. The construction of the genetic manipulation system is critical to study the relationship between F. oryzae and O. sativa. In the present study, the protoplast preparation and transformation system of F. oryzae was investigated. The key parameters affecting the efficiency of protoplast production, such as osmotic pressure stabilizer, enzyme digestion conditions, and fungal age, were studied. The results showed that F. oryzae strain obtained higher protoplast yield and effective transformation when treated with enzyme digestion solution containing 0.9mol L-1 KCl solution and 10 mg mL−1 glucanase at 30℃ with shaking 80 rpm for 2-3 h. When the protoplasts were plated on a regenerations-agar (RgA) medium containing 1M sucrose, the re-growth rate of protoplasts was the highest. We successfully acquired GFP-expressing transformants by transforming the pKD6-GFP vector into protoplasts. Further, the GFP expression in fungal hyphae possessed good stability and intensity during symbiosis in rice roots.The genetic manipulation system of endophytic fungus facilitates the further exploration the interaction between the endophytic fungus and their hosts.

A reductive radical relay strategy for the construction of fused benzo[e]isoindole-1,3,5-trione through a reaction of α-bromo ketones with maleimides in the presence of Ir(ppy)3 under visible-light irradiation is described. The protocol employs very mild reaction conditions and offers satisfactory yields. Moreover, the reaction proceeds through a cascade C(sp3)-Br/C(sp2)-H functionalization, double C-C bond formation, and oxidative aromatization sequence.

A regioselective synthesis of polysubstituted dihydropyrazoles and pyrazoles through an iodine-catalyzed oxidative cyclization strategy of aldehyde hydrazones with electron-deficient olefins is described. The protocol adopts very mild reaction conditions and provides desirable yields. The reaction is supposed to proceed via a cascade C-H functionalization, C-N bond formation, and oxidation sequential processes. The overall simplicity and regioselectivity of the catalytic system make this approach a valuable and step-economical tool to construct a C-C bond for the synthesis of Mefenpyr-Diethyl.

A variety of pyrrolo[3,4- c]pyrazole derivatives from readily available aldehyde hydrazones and maleimides via direct oxidative coupling under radical cascade reaction have been reported. This method offers satisfactory chemical yields and good functional group compatibility. Moreover, this practical approach is catalyzed by CuCl utilizing air as the oxidant and some control experiments were performed to elaborate the mechanism.

Dark septate endophytes (DSEs) are the typical representatives of root endophytic fungi in heavy metal (HM)-contaminated environments. However, little is known about their roles in the HMs tolerance of hosts and the underlying mechanism. Here, we investigated the biological roles and molecular mechanisms of a DSE strain Falciphora oryzae in alleviating cadmium (Cd) toxicities in rice. It was found that F. oryzae possessed a capacity of accumulating Cd in its vacuoles and chlamydospores. During symbiosis, F. oryzae conferred improved Cd tolerance to rice, decreasing Cd accumulation in roots and translocation to shoots. F. oryzae alleviated Cd toxicity to rice by sequestering Cd in its vacuoles. Further application of F. oryzae as fertilizer in the field could reduce Cd content in rice grains. We identified a SNARE Syntaxin 1 gene through proteomics, which participated in Cd tolerance of F. oryzae by regulating chlamydospore formation and vacuole enlargement. This study provided novel insights into how the DSEs and their host plants combat Cd stress.

Falciphora oryzae is a newly discovered member of dark septate endophytic fungi, first isolated from wild rice roots. Through symbiosis, it leads to the development of induced systemic resistance of rice against foliar infection caused by Magnaporthe oryzae. However, the mechanism underlying the development of this systemic resistance remains to be elucidated. Here, FoCcw14, a protein containing the CFEM domain, was identified in F. oryzae. By homologous recombination, we obtained the deletion mutant, ΔFoCcw14, which was sensitive to oxidative stresses. Moreover, we showed that FoCcw14 was required for fungal colonization and the generation of immunity when symbiotic with rice. Additionally, FoCcw14 interacted with a germin-like protein, OsGLP2, which is present in the rice apoplast. FoCcw14 promoted the accumulation of OsGLP2 in the host, and then OsGLP2 activated the downstream JA pathway, thereby co-regulating the development of induced systemic resistance.

A highly efficient copper-catalyzed intermolecular C(sp2)–H thioamination of maleimides with thiols and formamides in the presence of fluoroboric acid is reported using various readily available formamides as nitrogen sources and solvents. A diverse range of 3-amino-4-thiomaleimides is obtained with good yields under mild conditions, involving C–N and C–S bond formation. This methodology enriches current C–N and C–S bond formation chemistry and features operational simplicity and excellent functional-group tolerance.

Iodine-promoted C(sp 2)–H methylthiolation of maleimides using DMSO as synthon has been developed to afford 3-methylthiomaleimides in moderate yields under metal-free conditions. In addition, 3-thiomaleimides were synthesized from maleimides and thiols in the presence of iodine and triethylamine. The methods are simple and efficient for the formation of C–S bond.

An efficient silver-catalyzed intermolecular carbon-phosphorus difunctionalization of maleimides with indoles/pyrroles and organophosphorus compounds including dialkyl phosphites and diphenylphosphine oxide was developed. A diverse range of phosphonylated indolylmaleimides and pyrrolylmaleimides were obtained in good yields and excellent regioselectivity, involving C−P and C−C bond formations. This methodology is very practical and enables a one-step construction of difunctionalized maleimides.

Increasing evidence suggests that the endophytic fungus Piriformospora indica helps plants overcome various abiotic stresses, especially heavy metals. However, the mechanism of heavy metal tolerance has not yet been elucidated. Here, the role of P. indica in alleviating cadmium (Cd) toxicities in tobacco was investigated. It was found that P. indica improved Cd tolerance to tobacco, increasing Cd accumulation in roots but decreasing Cd accumulation in leaves. The colonization of P. indica altered the subcellular repartition of Cd, increasing the Cd proportion in cell walls while reducing the Cd proportion in membrane/organelle and soluble fractions. During Cd stress, P. indica significantly enhanced the peroxidase (POD) activity and glutathione (GSH) content in tobacco. The spatial distribution of GSH was further visualized by Raman spectroscopy, showing that GSH was distributed in the cortex of P. indica-inoculated roots while in the epidermis of the control roots. A LC-MS/MS-based label-free quantitative technique evaluated the differential proteomics of P. indica treatment vs. control plants under Cd stress. The expressions of peroxidase, glutathione synthase, and photosynthesis-related proteins were significantly upregulated. This study provided extensive evidence for how P. indica enhances Cd tolerance in tobacco at physiological, cytological, and protein levels.

An efficient and practical Cu(I)-catalyzed oxidative cyclization cascade reaction of diverse amines, alkyne esters and maleimides has been developed. The reactions can afford 4,6-dioxopyrrolo[3,4-b]pyrrole-2,3-dicarboxylates and related derivatives with satisfactory yields by altering the reaction conditions slightly. The substrate scope highlights the flexibility of the catalyst, and a reaction mechanism is also proposed.

Molecular dynamics simulations of water-based nanolubrication in Couette flow are carried out. The water molecules are simulated by the TIP3P model. Three different shear rates are 20 m/s and 40 m/s and 60 m/s, and the vertical pressure acted on the metal wall are 10GPa, 20 GPa, 30 GPa and 40 GPa respectively. The simulated results show that the greater pressure, the smaller the stable value of friction spacing, while the reduction rate of the stable value becomes small. Meanwhile, as pressure increases, the stabilization time is longer. However, under the same pressure, shear rate of influence on the friction spacing is not obvious. The friction spacing increases with the number of particles, showing that the presence of nanoparticles can enhance the bearing capacity.