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In nature, biochemical processes depend on polymorphism, a phenomenon by which discrete biomolecules can adopt specific conformations based on their environment. However, it is often difficult to explore the generation mechanism and achieve polymorphic control in artificial supramolecular assembly systems. In this work, we propose a feasible thought for exploring the transformation mechanism of polymorphism in peptide assembly from the perspective of thermodynamic regulation, which enables polymorphic composition to be limited by switchable intramolecular CHâ¯π attraction within a certain temperature range. Combined with the density functional theory calculations, we obtained thermodynamic theoretical data supporting the conformation transition and the underlying polymorphism formation principle. Afterward, we properly designed the peptide to alter the probability of CHâ¯π attraction occurring. Then, we selectively obtained a homogeneous morphological form with corresponding molecular conformation, which further demonstrated the important role of molecular conformational manipulation in polymorphism selection. This unique template-based strategy developed in this study may provide scientists with an additional line of thought to guide assembly paths in other polymorphic systems.
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BACKGROUND: The repair of upper lip defects is difficult and can result in asymmetry. The authors have developed a postauricular scalp composite tissue for the repair of upper lip defects. Herein, the authors, present the feasibility of scalp composite tissue grafts for repairing of upper lip defects. METHODS: The authors conducted a retrospective study of 10 patients who underwent scalp composite tissue transplantation for upper lip repair. The surgical procedure consisted of the excision of skin lesions or scar tissue from the upper lip to prepare the recipient area, and then the scalp composite tissue was excised behind the ear and transplanted to the upper lip defect. The authors reviewed the photographs and clinical notes of these patients. The patients' self-reported satisfaction with the repair effect was assessed. Tissue sections and hematoxylin and eosin staining of the scalp composite tissues were performed. RESULTS: All patients successfully underwent lesion resection and scalp composite tissue transplantation to repair the wound. There was no necrosis of the scalp composite tissue in the early postoperative period. The lip wound healed completely within 2 weeks. The mean follow-up time was 16 months, ranging from 12 to 20 months. Histologic sections and hematoxylin and eosin staining showed that the scalp composite tissue had abundant capillaries and dense fibrous connective tissue. All 10 patients were satisfied with the clinical effect of the procedure. CONCLUSION: Scalp composite tissue transplantation is a viable method for repairing upper lip defects. The special histomorphological characteristics of the scalp provide the basis for clinical application. LEVEL OF EVIDENCE: IV.
Assuntos
Estudos de Viabilidade , Couro Cabeludo , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Couro Cabeludo/cirurgia , Adulto , Resultado do Tratamento , Lábio/cirurgia , Satisfação do Paciente , Idoso , Neoplasias Labiais/cirurgia , Cicatrização/fisiologiaRESUMO
Fusarium head blight is a devastating disease that causes severe yield loses and mycotoxin contamination in wheat grain. Additionally, balancing the trade-off between wheat production and disease resistance has proved challenging. This study aimed to expand the genetic tools of the endophyte Phomopsis liquidambaris against Fusarium graminearum. Specifically, we engineered a UDP-glucosyltransferase-expressing P. liquidambaris strain (PL-UGT) using ADE1 as a selection marker and obtained a deletion mutant using an inducible promoter that drives Cas9 expression. Our PL-UGT strain converted deoxynivalenol (DON) into DON-3-G in vitro at a rate of 71.4 % after 36 h. DON inactivation can be used to confer tolerance in planta. Wheat seedlings inoculated with endophytic strain PL-UGT showed improved growth compared with those inoculated with wildtype P. liquidambaris. Strain PL-UGT inhibited the growth of Fusarium graminearum and reduced infection rate to 15.7 %. Consistent with this finding, DON levels in wheat grains decreased from 14.25 to 0.56 µg/g when the flowers were pre-inoculated with PL-UGT and then infected with F. graminearum. The expression of UGT in P. liquidambaris was nontoxic and did not inhibit plant growth. Endophytes do not enter the seeds nor induce plant disease, thereby representing a novel approach to fungal disease control.
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Ascomicetos , Endófitos , Fusarium , Glucosiltransferases , Doenças das Plantas , Tricotecenos , Triticum , Triticum/microbiologia , Triticum/genética , Tricotecenos/metabolismo , Fusarium/genética , Fusarium/efeitos dos fármacos , Fusarium/enzimologia , Endófitos/genética , Endófitos/enzimologia , Endófitos/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Ascomicetos/genética , Ascomicetos/efeitos dos fármacos , Ascomicetos/enzimologia , Resistência à Doença/genética , Micotoxinas/metabolismoRESUMO
Plant-associated microbiomes play important roles in plant health and productivity. However, despite fruits being directly linked to plant productivity, little is known about the microbiomes of fruits and their potential association with fruit health. Here, by integrating 16S rRNA gene, ITS high-throughput sequencing data, and microbiological culturable approaches, we reported that roots and fruits (pods) of peanut, a typical plant that bears fruits underground, recruit different bacterial and fungal communities independently of cropping conditions and that the incidence of pod disease under monocropping conditions is attributed to the depletion of Bacillus genus and enrichment of Aspergillus genus in geocarposphere. On this basis, we constructed a synthetic community (SynCom) consisting of three Bacillus strains from geocarposphere soil under rotation conditions with high culturable abundance. Comparative transcriptome, microbiome profiling, and plant phytohormone signaling analysis reveal that the SynCom exhibited more effective Aspergillus growth inhibition and pod disease control than individual strain, which was underpinned by a combination of molecular mechanisms related to fungal cell proliferation interference, mycotoxins biosynthesis impairment, and jasmonic acid-mediated plant immunity activation. Overall, our results reveal the filter effect of plant organs on the microbiome and that depletion of key protective microbial community promotes the fruit disease incidence.
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Arachis , Frutas , Microbiota , Doenças das Plantas , Raízes de Plantas , RNA Ribossômico 16S , Microbiologia do Solo , Frutas/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , RNA Ribossômico 16S/genética , Raízes de Plantas/microbiologia , Arachis/microbiologia , Aspergillus/genética , Aspergillus/isolamento & purificação , Bacillus/genética , Bacillus/isolamento & purificação , Reguladores de Crescimento de Plantas/metabolismo , Fungos/genética , Fungos/classificação , Fungos/isolamento & purificação , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificaçãoRESUMO
Protein active states are dynamically regulated by various modifications; thus, endogenous protein modification is an important tool for understanding protein functions and networks in complicated biological systems. Here we developed a new pyridinium-based approach to label lysine residues under physiological conditions that is low-toxicity, efficient, and lysine-selective. Furthermore, we performed a large-scale analysis of the â¼70% lysine-selective proteome in MCF-7 cells using activity-based protein profiling (ABPP). We quantifically assessed 1216 lysine-labeled peptides in cell lysates and identified 386 modified lysine sites including 43 mitochondrial-localized proteins in live MCF-7 cells. Labeled proteins significantly preferred the mitochondria. This pyridinium-based methodology demonstrates the importance of analyzing endogenous proteins under native conditions and provides a robust chemical strategy utilizing either lysine-selective protein labeling or spatiotemporal profiling in a living system.
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The reactivity of pyridine is a complex topic due to its unique electronic structure. The reactions of atomic boron with pyridine molecules in solid neon have been investigated using matrix isolation infrared absorption spectroscopy. Three products (marked as A, B, and C) were observed and characterized through 10B, D and 15N isotopic substitution pyridine regents as well as quantum chemical calculations. In the reaction, the ground-state boron atom can attack the lone pair electrons of the nitrogen atom in the pyridine molecule, resulting in the formation of a 1-boropyridinyl radical (A). Alternatively, addition to the aromatic π-system of pyridine can occur in a [1,4] type, leading to the formation of a B[η2(1,4)-C5H5N] complex (B). Under UV-visible light (280 < λ < 580 nm) irradiation, these two compounds can further undergo photo-isomerization to form BN-embedded seven-membered azaborepin compounds (C). The observation of species A, B, and the subsequent photo-isomerization to species C is consistent with theoretical predictions, indicating that these reactions are kinetically favorable. This research provides valuable insights into the future design and synthesis of corresponding BN heterocyclic derivatives.
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Chemical labeling methods for proteins are highly researched. Herein, we introduced ß-carbonyl sulfonium compounds for selective cysteine modification in proteins within biological systems. Structural tuning led to sulfonium-based probes with high reactivity and selectivity. These probes show excellent biocompatibility, cell uptake, and specificity towards cysteine profiling in live cells.
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Cisteína , Compostos de Sulfônio , Cisteína/química , Proteínas/química , Compostos de Sulfônio/químicaRESUMO
AIMS: In this study, the control effects of synthetic microbial communities composed of peanut seed bacteria against seed aflatoxin contamination caused by Aspergillus flavus and root rot by Fusarium oxysporum were evaluated. METHODS AND RESULTS: Potentially conserved microbial synthetic communities (C), growth-promoting synthetic communities (S), and combined synthetic communities (CS) of peanut seeds were constructed after 16S rRNA Illumina sequencing, strain isolation, and measurement of plant growth promotion indicators. Three synthetic communities showed resistance to root rot and CS had the best effect after inoculating into peanut seedlings. This was achieved by increased defense enzyme activity and activated salicylic acid (SA)-related, systematically induced resistance in peanuts. In addition, CS also inhibited the reproduction of A. flavus on peanut seeds and the production of aflatoxin. These effects are related to bacterial degradation of toxins and destruction of mycelia. CONCLUSIONS: Inoculation with a synthetic community composed of seed bacteria can help host peanuts resist the invasion of seeds by A. flavus and seedlings by F. oxysporum and promote the growth of peanut seedlings.
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Aflatoxinas , Sementes , RNA Ribossômico 16S/genética , Sementes/microbiologia , Fungos/genética , Plântula/microbiologia , Bactérias/genética , Arachis/microbiologiaRESUMO
BACKGROUND: The repair of nasal alar defects is challenging for plastic surgeons, and there is currently no standard operation. Herein, the authors reported the clinical outcomes of a nasofacial groove pedicled flap for the reconstruction of alar defect. METHODS: This retrospective study included patients who underwent the nasofacial groove pedicled flap for the reconstruction of alar defect between January 2018 and June 2020. Photographs of standard facial postures were taken before and after surgery to record the surgical results of the patients. The patient's medical history was reviewed retrospectively. Self-reported satisfaction of patients on scar morphology and reconstructive effect were evaluated with a questionnaire survey. RESULTS: There were 26 eligible patients enrolled, and all patients were followed up for more than 1 year after surgery. All flaps were free of ischemia and necrosis and healed well. No patient experienced restricted nostril ventilation. Eight patients underwent reoperation to trim the flap pedicle and the scar. Eight patients (8/26) reported "very satisfied," and 17 patients (17/26) reported "satisfied" with the repair effect and scar morphology. One patient went through multiple laser treatments to improve her scars but still remained visible hyperpigmentation. She was dissatisfied with postoperative flap pigmentation but was satisfied with the correction effect. CONCLUSIONS: The clinical results indicated that the nasal groove flap was safe for the treatment of the lateral alar defect, and the patients were satisfied with the clinical results. The authors believe that this flap can be used as an alternative method for repairing the lateral alar defect. LEVEL OF EVIDENCE: Level -IV, therapeutic study.
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Endophytic symbioses between plants and fungi are a dominant feature of many terrestrial ecosystems, yet little is known about the signaling that defines these symbiotic associations. Hydrogen peroxide (H2O2) is recognized as a key signal mediating the plant adaptive response to both biotic and abiotic stresses. However, the role of H2O2 in plant-fungal symbiosis remains elusive. Using a combination of physiological analysis, plant and fungal deletion mutants, and comparative transcriptomics, we reported that various environmental conditions differentially affect the interaction between Arabidopsis and the root endophyte Phomopsis liquidambaris, and link this process to alterations in H2O2 levels and H2O2 fluxes across root tips. We found that enhanced H2O2 efflux leading to a moderate increase in H2O2 levels at the plant-fungal interface is required for maintaining plant-fungal symbiosis. Disturbance of plant H2O2 homeostasis compromises the symbiotic ability of plant roots. Moreover, the fungus-regulated H2O2 dynamics modulate the rhizosphere microbiome by selectively enriching for the phylum Cyanobacteria, with strong antioxidant defenses. Our results demonstrated that the regulation of H2O2 dynamics at the plant-fungal interface affects the symbiotic outcome in response to external conditions and highlight the importance of the root endophyte in reshaping the rhizosphere microbiota.
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Arabidopsis , Endófitos , Homeostase , Peróxido de Hidrogênio , Microbiota , Raízes de Plantas , Rizosfera , Simbiose , Arabidopsis/microbiologia , Arabidopsis/fisiologia , Endófitos/fisiologia , Peróxido de Hidrogênio/metabolismo , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Ascomicetos/fisiologiaRESUMO
KDF1 has been reported to be correlated with carcinogenesis. However, its role and mechanism are far from clear. To explore the possible role and underlying mechanism of KDF1 in lung adenocarcinoma (LUAD), we investigated KDF1 expression in LUAD tissues and the influence of KDF1 in the phenotype of LUAD cells (A549 and PC-9) as well as the underlying mechanism. Compared to non-tumor lung epithelial cells, KDF1 was upregulated in the cancer cells of the majority of LUAD patients, and its expression was correlated with tumor size. Patients with enhanced KDF1 in cancer cells (compared with paired adjacent non-neoplastic lung epithelial cells) had shorter overall survival than patients with no increased KDF1 in cancer cells. Knockdown of KDF1 inhibited the migration, proliferation and invasion of LUAD cells in vitro. And overexpression of KDF1 increased the growth of the subcutaneous tumors in mice. In terms of molecular mechanisms, overexpression of KDF1 induced the expression of AKT, p-AKT and p-STAT3. In KDF1-overexpressing A549 cells, inhibition of the STAT3 pathway decreased the level of AKT and p-AKT, whereas inhibition of the AKT pathway had no effect on the activation of STAT3. Inhibition of STAT3 or AKT pathways reversed the promoting effects of KDF1 overexpression on the LUAD cell phenotype and STAT3 inhibition appeared to have a better effect. Finally, in the cancer cells of LUAD tumor samples, the KDF1 level was observed to correlate positively with the level of p-STAT3. All these findings suggest that KDF1, which activates STAT3 and the downstream AKT pathway in LUAD, acts as a tumor-promoting factor and may represent a therapeutic target.
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Cell surface proteins (CSPs) are valuable targets for therapeutic agents, but achieving highly selective CSP enrichment in cellular physiology remains a technical challenge. To address this challenge, we propose a newly developed sulfo-pyridinium ester (SPE) cross-linking probe, followed by two-step imaging and enrichment. The SPE probe showed higher efficiency in labeling proteins than similar NHS esters at the level of cell lysates and demonstrated specificity for Lys in competitive experiments. More importantly, this probe could selectively label the cell membranes in cell imaging with only negligible labeling of the intracellular compartment. Moreover, we successfully performed this strategy on MCF-7 live cells to label 425 unique CSPs from 1162 labeled proteins. Finally, we employed our probe to label the CSPs of insulin-cultured MCF-7, revealing several cell surface targets of key functional biomarkers and insulin-associated pathogenesis. The above results demonstrate that the SPE method provides a promising tool for the selective labeling of cell surface proteins and monitoring transient cell surface events.
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Insulinas , Proteoma , Humanos , Proteoma/metabolismo , Membrana Celular/metabolismo , Proteínas de Membrana/metabolismo , Células MCF-7RESUMO
Lysine-specific demethylase 1 (LSD1) is a promising therapeutic target, especially in cancer treatment. Despite several LSD1 inhibitors being discovered for the cofactor pocket, none are FDA-approved. We aimed to develop stabilized peptides for irreversible LSD1 binding, focusing on unique cysteine residue Cys360 in LSD1 and SNAIL1. We created LSD1 C360-targeting peptides, like cyclic peptide S9-CMC1, using our Cysteine-Methionine cyclization strategy. S9-CMC1 effectively inhibited LSD1 at the protein level, as confirmed by MS analysis showing covalent bonding to Cys360. In cells, S9-CMC1 inhibited LSD1 activity, increasing H3K4me1 and H3K4me2 levels, leading to G1 cell cycle arrest and apoptosis and inhibiting cell proliferation. Remarkably, S9-CMC1 showed therapeutic potential in A549 xenograft animal models, regulating LSD1 activity and significantly inhibiting tumor growth with minimal organ damage. These findings suggest LSD1 C360 as a promising site for covalent LSD1 inhibitors' development.
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Cisteína , Neoplasias , Animais , Humanos , Peptídeos/farmacologia , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Proliferação de Células , Histona Desmetilases/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Linhagem Celular TumoralRESUMO
Through systematic optimization of halopyridinium compounds, we established a peptide coupling protocol utilizing 4-iodine N-methylpyridinium (4IMP) for solid-phase peptide synthesis (SPPS). The 4IMP coupling reagent is easily prepared, bench stable, and cost-effective. Employing 4IMP in the SPPS process has showcased remarkable chemoselectivity and efficiency, effectively eliminating racemization and epimerization. This achievement has been substantiated through the successful synthesis of a range of peptides via the direct utilization of commercially available amino acid substrates for SPPS.
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Peptídeos , Compostos de Piridínio , Peptídeos/química , Aminoácidos/química , Técnicas de Síntese em Fase Sólida/métodosRESUMO
Fungal endophytes play critical roles in helping plants adapt to adverse environmental conditions. The root endophyte Phomopsis liquidambaris can promote the growth and disease control of peanut plants grown under monocropping systems; however, how such beneficial traits are produced is largely unknown. Since the plant endophytic microbiome is directly linked to plant growth and health, and the composition of which has been found to be potentially influenced by microbial inoculants, this study aims to clarify the roles of root endophytic bacterial communities in P. liquidambaris-mediated plant fitness enhancement under monocropping conditions. Here, we found that P. liquidambaris inoculation induced significant changes in the root bacterial community: enriching some beneficial bacteria such as Bradyrhizobium sp. and Streptomyces sp. in the roots, and improving the core microbial-based interaction network. Next, we assembled and simplified a synthetic community (SynII) based on P. liquidambaris-derived key taxa, including Bacillus sp. HB1, Bacillus sp. HB9, Burkholderia sp. MB7, Pseudomonas sp. MB2, Streptomyces sp. MB6, and Bradyrhizobium sp. MB15. Furthermore, the application of the simplified synthetic community suppressed root rot caused by Fusarium oxysporum, promoted plant growth, and increased peanut yields under continuous monocropping conditions. The resistance of synII to F. oxysporum is related to the increased activity of defense enzymes. In addition, synII application significantly increased shoot and root biomass, and yield by 35.56%, 81.19%, and 34.31%, respectively. Collectively, our results suggest that the reshaping of root core microbiota plays an important role in the probiotic-mediated adaptability of plants under adverse environments.
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Bacillus , Microbiota , Endófitos , Resistência à Doença , Arachis/microbiologia , Bactérias/genética , Raízes de Plantas/microbiologiaRESUMO
BACKGROUND: Restricted ventilation is common after rhinoplasty with an endogenous extension stent. The authors proposed an exogenous extension stent concept for Asian rhinoplasty patients to avoid this problem. Herein, we introduce an innovative stent in rhinoplasty for Asians, which is an application of this concept. METHODS: An L-shaped expanded polytetrafluoroethylene is hand-carved, and the long arm is placed at the nose back to improve the flatness of the nose, while the short arm supports the nasal column to raise the nose tip. The prosthesis does not occupy nasal volume and therefore theoretically does not affect nasal ventilation. The fan-shaped ear cartilage was placed at the nasal tip to prevent visualization of the nasal tip. The safety and effectiveness of this method were verified through 20 years of clinical practice. The difficulty of learning and popularizing the method was tested through the course of rhinoplasty among 22 plastic surgeons. RESULTS: After 20 years of clinical practice, it was found that this stent could not only effectively improve the nasal dorsum and tip morphology, but also did not actually affect the nasal volume and thus did not affect the nasal ventilation of patients. Among the trainees in plastic surgery, we found that it was not difficult to learn this method of rhinoplasty and the trainees could complete the prosthesis carving well after standardized training. CONCLUSION: This stent consisting of expanded polytetrafluoroethylene and ear cartilage is suitable in rhinoplasty for Asians with significant advantages, one of which is that it has no risk of resulting in restricted nasal ventilation. LEVEL OF EVIDENCE: Level IV.
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Implantes Dentários , Rinoplastia , Humanos , Rinoplastia/métodos , Cartilagem da Orelha/cirurgia , Politetrafluoretileno , Nariz/cirurgia , Stents , Septo Nasal/cirurgia , Cartilagens Nasais/cirurgiaRESUMO
Rice spikelet rot disease (RSRD) caused by Fusarium proliferatum seriously reduces rice yield and produces mycotoxins that threaten human health. The root symbiotic endophytic fungus Phomopsis liquidambaris reduces RSRD incidence and fumonisins accumulation in grain by 21.5 and 9.3%, respectively, while the mechanism of disease resistance remains largely elusive. Here, we found that B3 significantly reduced the abundance of pathogen from 79.91 to 2.84% and considerably enriched resistant microbes Pseudomonas and Proteobacteria in the spikelet microbial community. Further study revealed that B3 altered the metabolites of spikelets, especially hordenine and l-aspartic acid, which played a key role in reshaping the microbiome and supporting the growth of the functional core microbe Pseudomonas, and inhibited the pathogen growth and mycotoxin production. This study provided a feasibility of regulating the function of aboveground microbial communities by manipulating plant subsurface tissues to control disease and mycotoxin pollutants in agricultural production.
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Fumonisinas , Fusarium , Micotoxinas , Oryza , Humanos , Micotoxinas/metabolismo , Oryza/metabolismo , Fumonisinas/análise , Fungos/metabolismo , Grão Comestível/químicaRESUMO
The ability to balance conflicting functional demands is critical for ensuring organismal survival. The transcription and repair of the mitochondrial genome (mtDNA) requires separate enzymatic activities that can sterically compete1, suggesting a life-long trade-off between these two processes. Here in Caenorhabditis elegans, we find that the bZIP transcription factor ATFS-1/Atf5 (refs. 2,3) regulates this balance in favour of mtDNA repair by localizing to mitochondria and interfering with the assembly of the mitochondrial pre-initiation transcription complex between HMG-5/TFAM and RPOM-1/mtRNAP. ATFS-1-mediated transcriptional inhibition decreases age-dependent mtDNA molecular damage through the DNA glycosylase NTH-1/NTH1, as well as the helicase TWNK-1/TWNK, resulting in an enhancement in the functional longevity of cells and protection against decline in animal behaviour caused by targeted and severe mtDNA damage. Together, our findings reveal that ATFS-1 acts as a molecular focal point for the control of balance between genome expression and maintenance in the mitochondria.
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Proteínas de Caenorhabditis elegans , DNA Mitocondrial , Animais , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Caenorhabditis elegans/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Dano ao DNA , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismoRESUMO
Anthropogenic nitrogen inputs lead to a high ammonium (NH4+)/nitrate (NO3-) ratio in the soil, which restricts hyphal spreading of soil fungi. Access of symbiotic fungi to roots is a prerequisite for plant-fungal interactions. Hyphosphere bacteria protect fungi from environmental stress, yet the impact of hyphosphere bacteria on adaptation of host fungi to NH4+-enriched conditions remains unclear. By developing soil microcosm assays, we report that a plant-symbiotic fungus, Phomopsis liquidambaris, harbors specific hyphosphere bacteria that facilitate hyphal spreading and assist in the root colonization in NH4+-enriched soil. Genetic manipulation, 16S rRNA gene analysis and coinoculation assays revealed that the genus Enterobacter was enriched in the hyphosphere of NH4+-sensitive wild-type compared to NH4+-preferring nitrite reductase-deficient strain. The representative Enterobacter sp. SZ2-promoted hyphal spreading is only evident in nonsterilized soil. We further identified an increased abundance and diversity of ammonia-oxidizing archaea (AOA) and a synchronously decreased NH4+:NO3- ratio following SZ2 inoculation. Microbial supplementation and inhibitor assays showed that AOA-mediated reduction in NH4+:NO3- ratio is responsible for SZ2-enhanced fungal adaptation to NH4+-enriched conditions. The Ph. liquidambaris-Enterobacter-AOA triple interaction promoted rice growth in NH4+-enriched soil. Our study reveals the essential role of hyphosphere microorganism-based hyphal spreading in plant-fungal symbiosis establishment within nitrogen-affected agroecosystems.
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Compostos de Amônio , Simbiose , RNA Ribossômico 16S/genética , Solo/química , Bactérias , Amônia , Nitrogênio , Microbiologia do Solo , Raízes de Plantas/microbiologiaRESUMO
Ectomycorrhizal fungi play an irreplaceable role in phosphorus cycling. However, ectomycorrhizal fungi have a limited ability to dissolve chelated inorganic phosphorus, which is the main component of soil phosphorus. Endofungal bacteria in ectomycorrhizal fruiting bodies are always closely related to the ecological function of ectomycorrhizal fungi. In this study, we explore endofungal bacteria in the fruiting body of Tylopilus neofelleus and their function during the absorption of chelated inorganic phosphorus by host pine through the ectomycorrhizal system. The results showed that the endofungal bacterial microbiota in the fruiting body of T. neofelleus might be related to the dissolution of chelated inorganic phosphorus in soil. The soluble phosphorus content in the combined system of T. neofelleus and endofungal bacteria Bacillus sp. strain B5 was five times higher than the sum of T. neofelleus-only treatment and Bacillus sp. strain B5-only treatment in the dissolution experiment of chelated inorganic phosphorus. The results showed that T. neofelleus not only promoted the proliferation of Bacillus sp. strain B5 in the combined system but also improved the expression of genes related to organic acid metabolism, as assesed by transcriptomic analysis. Lactic acid content was five times higher in the combined system than the sum of T. neofelleus-only treatment and Bacillus sp. strain B5-only treatment. Two essential genes related to lactate metabolism of Bacillus sp. strain B5, gapA and pckA, were significantly upregulated. Finally, in a pot experiment, we verified that T. neofelleus and Bacillus sp. strain B5 could synergistically promote the absorption of chelated inorganic phosphorus by Pinus sylvestris in a ternary symbiotic system. IMPORTANCE Ectomycorrhizal fungi (ECMF) have a limited ability to dissolve chelated inorganic phosphorus, which is the main component of soil phosphorus. In the natural environment, the extraradical hyphae of ECMF alone may not satisfy the phosphorus demand of the plant ectomycorrhizal system. In this study, our results innovatively show that the ectomycorrhizal system might be a ternary symbiont in which ectomycorrhizal fungi might recruit endofungal bacteria that could synergistically promote the mineralization of chelated inorganic phosphorus, which ultimately promotes plant phosphorus absorption by the ectomycorrhizal system.