RESUMEN
Soil (or plant) water deficit accelerates plant reproduction. However, the underpinning molecular mechanisms remain unknown. By modulating cell division/number, ABSCISIC ACID-INSENSITIVE 5 (ABI5), a key bZIP (basic (region) leucine zippers) transcription factor, regulates both seed development and abiotic stress responses. The KIP-RELATED PROTEIN (KRP) cyclin-dependent kinases (CDKs) play an essential role in controlling cell division, and SHOOT MERISTEMLESS (STM) plays a key role in the specification of flower meristem identity. Here, our findings show that abscisic acid (ABA) signaling and/or metabolism in adjust reproductive outputs (such as rosette leaf number and open flower number) under water-deficient conditions in Arabidopsis (Arabidopsis thaliana) plants. Reproductive outputs increased under water-sufficient conditions but decreased under water-deficient conditions in the ABA signaling/metabolism mutants abscisic acid2-1 (aba2-1), aba2-11, abscisic acid insensitive3-1 (abi3-1), abi4-1, abi5-7, and abi5-8. Further, under water-deficient conditions, ABA induced-ABI5 directly bound to the promoter of KRP1, which encodes a CDK that plays an essential role in controlling cell division, and this binding subsequently activated KRP1 expression. In turn, KRP1 physically interacted with STM, which functions in the specification of flower meristem identity, promoting STM degradation. We further demonstrate that reproductive outputs are adjusted by the ABI5-KRP1-STM molecular module under water-deficient conditions. Together, our findings reveal the molecular mechanism by which ABA signaling and/or metabolism regulate reproductive development under water-deficient conditions. These findings provide insights that may help guide crop yield improvement under water deficiency.
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Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Flores , Regulación de la Expresión Génica de las Plantas , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Arabidopsis/fisiología , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Ácido Abscísico/metabolismo , Flores/genética , Flores/crecimiento & desarrollo , Flores/fisiología , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Transducción de Señal , Meristema/genética , Meristema/crecimiento & desarrollo , Meristema/metabolismo , Reproducción , Mutación/genética , Quinasas Ciclina-Dependientes/metabolismo , Quinasas Ciclina-Dependientes/genética , Proteínas de HomeodominioRESUMEN
Dendrobium officinale is a rare and precious medicinal plant. Southern blight is a destructive disease in the artificial cultivation of D. officinale, and one of its pathogens is Sclerotium delphinii. S. delphinii is a phytopathogenic fungus with a wide host range with extremely strong pathogenicity. In this study, S. delphinii was isolated from D. officinale with southern blight. Subsequently, this specific strain underwent thorough whole-genome sequencing using the PacBio Sequel II platform, which employed single-molecule real-time (SMRT) technology. Comprehensive annotations were obtained through functional annotation of protein sequences using various publicly available databases. The genome of S. delphinii measures 73.66 Mb, with an N90 contig size of 2,707,110 bp, and it contains 18,506 putative predictive genes. This study represents the first report on the genome size assembly and annotation of S. delphinii, making it the initial species within the Sclerotium genus to undergo whole-genome sequencing, which can provide solid data and a theoretical basis for further research on the pathogenesis, omics of S. delphinii.
RESUMEN
The Erp3 protein, which is an important member of the p24 family, is primarily responsible for the transport of cargo from the ER to the Golgi apparatus in Saccharomyces cerevisiae. However, the function of Erp3 in plant pathogenic fungi has not been reported. In this study, we characterized the ERP3 gene in Ceratocystis fimbriata, which causes the devastating disease sweetpotato black rot. The ΔCferp3 mutants exhibited slow growth, reduced conidia production, attenuated virulence, and reduced ability to induce host to produce toxins. Further analysis revealed that CfErp3 was localized in the ER and vesicles and regulated endocytosis, cell wall integrity, and osmotic stress responses, modulated ROS levels, and the production of ipomeamarone during pathogen-host interactions. These results indicate that CfErp3 regulates C. fimbriata growth and pathogenicity as well as the production of ipomeamarone in sweetpotato by controlling endocytosis, oxidative homeostasis, and responses to cell wall and osmotic stresses.
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Ascomicetos , Sesquiterpenos , Virulencia/genética , Ceratocystis , Saccharomyces cerevisiaeRESUMEN
To investigate the potential antifungal mechanisms of rhizosphere Actinobacteria against Ceratocystis fimbriata in sweet potato, a comprehensive approach combining biochemical analyses and multi-omics techniques was employed in this study. A total of 163 bacterial strains were isolated from the rhizosphere soil of sweet potato. Among them, strain MEPS155, identified as Streptomyces djakartensis, exhibited robust and consistent inhibition of C. fimbriata mycelial growth in in vitro dual culture assays, attributed to both cell-free supernatant and volatile organic compounds. Moreover, strain MEPS155 demonstrated diverse plant growth-promoting attributes, including the production of indole-3-acetic acid, 1-aminocyclopropane-1-carboxylate deaminase, phosphorus solubilization, nitrogen fixation, and enzymatic activities such as cellulase, chitinase, and protease. Notably, strain MEPS155 exhibited efficacy against various sweet potato pathogenic fungi. Following the inoculation of strain MEPS155, a significant reduction (P < 0.05) in malondialdehyde content was observed in sweet potato slices, indicating a potential protective effect. The whole genome of MEPS155 was characterized by a size of 8,030,375 bp, encompassing 7234 coding DNA sequences and 32 secondary metabolite biosynthetic gene clusters. Transcriptomic analysis revealed 1869 differentially expressed genes in the treated group that cultured with C. fimbriata, notably influencing pathways associated with porphyrin metabolism, fatty acid biosynthesis, and biosynthesis of type II polyketide products. These alterations in gene expression are hypothesized to be linked to the production of secondary metabolites contributing to the inhibition of C. fimbriata. Metabolomic analysis identified 1469 potential differently accumulated metabolites (PDAMs) when comparing MEPS155 and the control group. The up-regulated PDAMs were predominantly associated with the biosynthesis of various secondary metabolites, including vanillin, myristic acid, and protocatechuic acid, suggesting potential inhibitory effects on plant pathogenic fungi. Our study underscores the ability of strain S. djakartensis MEPS155 to inhibit C. fimbriata growth through the production of secretory enzymes or secondary metabolites. The findings contribute to a theoretical foundation for future investigations into the role of MEPS155 in postharvest black rot prevention in sweet potato.
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Ascomicetos , Ipomoea batatas , Enfermedades de las Plantas , Rizosfera , Streptomyces , Ipomoea batatas/microbiología , Streptomyces/genética , Streptomyces/metabolismo , Streptomyces/aislamiento & purificación , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Ascomicetos/crecimiento & desarrollo , Ascomicetos/metabolismo , Ascomicetos/genética , Microbiología del Suelo , Antifúngicos/farmacología , Antifúngicos/metabolismo , MultiómicaRESUMEN
The fungal cell wall is the first layer exposed to the external environment. The cell wall has key roles in regulating cell functions, such as cellular stability, permeability, and protection against stress. Understanding the structure of the cell wall and the mechanism of its biogenesis is important for the study of fungi. Highly conserved in fungi, including Magnaporthe oryzae, the cell wall-integrity (CWI) pathway is the primary signaling cascade regulating cell-wall structure and function. The CWI pathway has been demonstrated to correlate with pathogenicity in many phytopathogenic fungi. In the synthesis of the cell wall, the CWI pathway cooperates with multiple signaling pathways to regulate cell morphogenesis and secondary metabolism. Many questions have arisen regarding the cooperation of different signaling pathways with the CWI pathway in regulating cell-wall synthesis and pathogenicity. In this review, we summarized the latest advances in the M. oryzae CWI pathway and cell-wall structure. We discussed the CWI pathway components and their involvement in different aspects, such as virulence factors, the possibility of the pathway as a target for antifungal therapies, and crosstalk with other signaling pathways. This information will aid in better understanding the universal functions of the CWI pathway in regulating cell-wall synthesis and pathogenicity in M. oryzae. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Magnaporthe , Oryza , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Virulencia , Oryza/microbiología , Pared Celular/metabolismo , Enfermedades de las Plantas/microbiología , Regulación Fúngica de la Expresión GénicaRESUMEN
A Gram-positive, aerobic actinomycete, designated strain KLBMP 9356T, was isolated from weathered potash tailings soil sampled in Xuzhou, Jiangsu Province, PR China. The colonies were cream-coloured, convex and rounded. The optimal growth conditions of strain KLBMP 9356T were 1 % (w/v) NaCl, 28 °C and pH 7. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain KLBMP 9356T showed the highest similarity to Nocardioides zhouii CGMCC 1.11084T (98.9 %) and Nocardioides glacieisoli CGMCC 1.11097T (98.7 %). Results from two tree-making algorithms supported the position that strain KLBMP 9356T forms a stable clade with N. zhouii CGMCC 1.11084T and N. glacieisoli CGMCC 1.11097T. Strain KLBMP 9356T exhibited low digital DNA-DNA hybridization values with N. zhouii CGMCC 1.11084T (27.6 %) and N. glacieisoli CGMCC 1.11097T (31.4 %). The average nucleotide identity values between strain KLBMP 9356T and N. zhouii CGMCC 1.11084T and N. glacieisoli CGMCC 1.11097T were 83.8% and 85.9%, respectively. The peptidoglycan in the cell wall of the novel strain was ll-2,6-diaminopimelic acid and the predominant menaquinone was MK-8(H4). The major fatty acids (>10 %) were C17:1ω8c and C18:1ω9c. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, lyso-phospatidylglycerol and phosphatidylinositol. The genomic DNA G+C content was 71.6 mol%. Based on its morphological, chemotaxonomic and phylogenetic characteristics, strain KLBMP 9356T represents a novel species of the genus Nocardioides, for which the name Nocardioides potassii sp. nov. is proposed. The type strain is KLBMP 9356T (=CGMCC 4.7738T=NBRC 115493T).
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Ácidos Grasos , Fosfolípidos , Ácidos Grasos/química , Fosfolípidos/química , Nocardioides , Suelo , Filogenia , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Microbiología del Suelo , Vitamina K 2/químicaRESUMEN
A Gram-stain-positive, aerobic actinomycete strain, designated KLBMP 8922T, was isolated from a soil sample collected from weathering dolomite crust in Guizhou Province, PR China. KLBMP 8922T showed the 16S rRNA gene similarities to Yinghuangia seranimata CCTCC AA 206006T (98.7â%), Yinghuangia catbensis VN07A0015T (98.3â%) and Yinghuangia aomiensis M24DS4T (98.2â%). The taxonomic status of this strain was investigated by using a polyphasic approach. The aerial mycelia of KLBMP 8922T formed spore chains, and spores were cylindrical with smooth surfaces. The whole-cell sugars were ribose, mannose and galactose with traces of glucose and xylose. The diagnostic amino acids of the cell wall were ll-diaminopimelic acid, alanine and glutamic acid. The predominant menaquinones were MK-9(H6) and MK-9(H8). The diagnostic phospholipids were diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositolmannoside, phosphatidylethanolamine, an unidentified phospholipid and an unidentified lipid. The major cellular fatty acids (>10â%) were iso-C15â:â0, iso-C16â:â0 and iso-C16â:â1H. The genomic DNA G+C content was 72.0 mol%. The digital DNA-DNA hybridization (dDDH) value between KLBMP 8922T and Y. seranimata CCTCC AA 206006T was 24.1â%, and the average nucleotide identity (ANI) value was 81.0â%. On the basis of a combination of morphological, chemotaxonomic and phylogenetic characteristics, strain KLBMP 8922T represents a novel species of the genus Yinghuangia for which the name Yinghuangia soli sp. nov. is proposed. The type strain was KLBMP 8922T (= CGMCC 1.19360T = NBRC 115572T).
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Ácidos Grasos , Suelo , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Fosfolípidos/químicaRESUMEN
Strain KLBMP 9083T, a novel actinobacterium, was isolated from weathered soils collected from a karst area in Anshun, Guizhou Province, PR China. The taxonomic position of strain KLBMP 9083T was studied using the polyphasic approach. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain KLBMP 9083T formed a stabilized monophyletic clade with its closest relative strain Antribacter gilvus CGMCC 1.13856T (98.4â% 16S rRNA gene sequence similarity). The peptidoglycan hydrolysates contained alanine, glutamic acid, threonine and lysine. The polar lipids were composed of diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, an unidentified phosphoglycolipid, an unidentified phospholipid and an unidentified glycolipid. The predominant menaquinones were MK-9(H8) (87.1â%), MK-9(H6) (7.3â%) and MK-9(H4) (5.6â%). The major fatty acids (>10â%) were anteiso-C15â:â0 and iso-C15â:â0. The genomic DNA G+C content was 72.3 mol%. The digital DNA-DNA hybridization and average nucleotide identity values between strain KLBMP 9083T and A. gilvus CGMCC 1.13856T were 23.4 and 79.9â%, respectively. On the basis of morphological, chemotaxonomic and phylogenetic characteristics, strain KLBMP 9083T represents a novel species of the genus Antribacter, for which the name Antribacter soli sp. nov. is proposed. The type strain is KLBMP 9083T (=CGMCC 4.7737T=NBRC 115577T).
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Actinobacteria , Actinomycetales , Ácidos Grasos/química , Suelo , Filogenia , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Fosfolípidos , Vitamina K 2RESUMEN
AIMS: To provide valuable information for a comprehensive understanding of the multicellular behavior of Bacillus velezensis Bs916 regulated by surfactin and other natural signals by Transcriptome. METHODS AND RESULTS: Transcriptomics revealed a distinct effect on gene expression alterations caused by disruption of the surfactin gene cluster(Δsrf) and 100 µg/ml surfactin addition(Δsrf + SRF). A total of 1573 differential expression genes were identified among Bs916, Δsrf, and Δsrf + SRF and grouped into eight categories based on their expression profiles. RT-qPCR analysis of 30 candidate genes showed high consistency with those of transcriptome. Additionally, the expression of eight candidate genes regulated by surfactin in a dose-dependent manner was revealed by lacZ fusion. Based on the above evidence, we proposed that surfactin can act as an extracellular signal for monitoring biofilm formation in Bs916 by directly regulating the expression of AbrB, DegS-degU, and SinI-SinR, and indirectly regulating the phosphorylation of ComA and Spo0A. CONCLUSIONS: The biofilm of Δsrf was unable to restore significantly by surfactin addition, combined inclusion of surfactin (SRF), exopolysaccharide (EPS), and γ-poly-dl-glutamic acid (γ-PGA), results in significant restoration of Δsrf biofilm formation, thereby a preliminary model was presented about the molecular mechanism by which the signaling molecule surfactin regulates Bs916 multicellular behavior.
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Bacillus , Transcriptoma , Bacillus/fisiología , Perfilación de la Expresión Génica , Familia de Multigenes , Biopelículas , Bacillus subtilis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Lipopéptidos/farmacología , Lipopéptidos/metabolismoRESUMEN
BACKGROUND: Postoperative cognitive dysfunction (POCD) has been reported as a significant complication in elderly patients. Various methods have been proposed for reducing the incidence and severity of POCD. Intravenous lidocaine administration has been reported in the literature to reduce POCD, but the effect of lidocaine remains controversial. METHODS: We screened Medline, Embase, Cochrane Library, and China National Knowledge Infrastructure (up to April 2022) databases following a search strategy for intravenous lidocaine on POCD. We also screened related bibliographies on lidocaine for POCD. Ten articles comprising 1517 patients were selected and analyzed. We divided the postoperative follow-up period as follows: short term (<30 days), medium term (30-90 days), and long term (>90 days). OUTCOMES: We found that lidocaine could attenuate the overall incidence of POCD, especially in the short term. There were no differences between lidocaine and placebo on the overall severity of POCD. CONCLUSION: Lidocaine administered intravenously could attenuate the overall incidence of POCD and its severity in the short term.
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Complicaciones Cognitivas Postoperatorias , Anciano , Humanos , Administración Intravenosa , China , Bases de Datos Factuales , LidocaínaRESUMEN
BACKGROUND: Emergence delirium (ED) is generally occurred after anesthesia associated with increased risks of long-term adverse outcomes. Therefore, this study aimed to evaluate the efficacy of preconditioning with nasal splint and mouth-breathing training on prevention of ED after general anesthesia. METHODS: This randomized controlled trial enrolled 200 adult patients undergoing ESS. Patients were randomized to receive either nasal splinting and mouth breathing training (n = 100) or standard care (n = 100) before surgery. The primary outcome was the occurrence of ED within 30 min of extubation, assessed using the Riker Sedation-Agitation Scale. Logistic regression identified risk factors for ED. RESULTS: Totally 200 patients were randomized and 182 aged from 18 to 82 years with 59.9% of males were included in the final analysis (90 in C-group and 92 in P-group). ED occurred in 16.3% of the intervention group vs. 35.6% of controls (P = 0.004). Male sex, smoking and function endoscopic sinus surgery (FESS) were independent risk factors for ED. CONCLUSIONS: Preoperative nasal splinting and mouth breathing training significantly reduced the incidence of emergence delirium in patients undergoing endoscopic sinus surgery. TRIAL REGISTRATION: ChiCTR1900024925 ( https://www.chictr.org.cn/index.aspx ) registered on 3/8/2019.
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Anestesiología , Delirio del Despertar , Adulto , Humanos , Masculino , Delirio del Despertar/prevención & control , Respiración por la Boca , Extubación Traqueal , Anestesia GeneralRESUMEN
SnRK1 protein kinase plays hub roles in plant carbon and nitrogen metabolism. However, the function of SnRK1 in legume nodulation and symbiotic nitrogen fixation is still elusive. In this study, we identified GmNodH, a putative sulfotransferase, as an interacting protein of GmSnRK1 by yeast two-hybrid screen. The qRT-PCR assays indicate that GmNodH gene is highly expressed in soybean roots and could be induced by rhizobial infection and nitrate stress. Fluorescence microscopic analyses showed that GmNodH was colocalized with GsSnRK1 on plasma membrane. The physical interaction between GmNodH and GmSnRK1 was further verified by using split-luciferase complementary assay and pull-down approaches. In vitro phosphorylation assay showed that GmSnRK1 could phosphorylate GmNodH at Ser193. To dissect the function and genetic relationship of GmSnRK1 and GmNodH in soybean, we co-expressed the wild-type and mutated GmSnRK1 and GmNodH genes in soybean hairy roots and found that co-expression of GmSnRK1/GmNodH genes significantly promoted soybean nodulation rates and the expression levels of nodulation-related GmNF5α and GmNSP1 genes. Taken together, this study provides the first biological evidence that GmSnRK1 may interact with and phosphorylate GmNodH to synergistically regulate soybean nodulation.
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Glycine max , Nodulación de la Raíz de la Planta , Nodulación de la Raíz de la Planta/genética , Glycine max/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fijación del Nitrógeno/genética , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Simbiosis/genética , Regulación de la Expresión Génica de las PlantasRESUMEN
Predatory mites are important biological control agents used against phytophagous mites and small insects. They face various environmental pressures, especially fluctuating climate factors. Neoseiulus californicus, a commercially available phytoseiid mite, is adapted to a wide range of temperature conditions. We investigated the regulatory mechanisms governing the plastic response of N. californicus for coping with environmental temperature variations. The mitogen-activated protein kinase (MAPK) signaling pathway is a highly conserved pathway of cell signal transduction that responds to environmental stress. We isolated two MAPKK genes (NcMAPKK4 and NcMAPKK6) from N. californicus and studied their functions. Developmental stage-specific expression level analysis showed that in adults, particularly females, NcMAPKK4 and NcMAPKK6 levels were higher than in other developmental stages. The expression level analysis at extremely high and low temperature conditions demonstrated that NcMAPKK4 could be induced significantly by adverse thermal stresses, whereas NcMAPKK6 distinctly responded to heat shock, indicating their different roles in thermal stress responses. After silencing of NcMAPKK4, both heat and cold resistance decreased significantly, whereas NcMAPKK6 knockdown had a greater influence on heat resistance. Knockdown of NcMAPKKs also reduced the activities of antioxidant enzymes, suggesting the regulation of NcMAPKKs was closely related to the antioxidant process in oxidative stress caused by external stimuli. These results indicate an important role of NcMAPKKs in the response to thermal stress and provide insight into the MAPK cascade pathway in the environmental adaptation mechanisms of phytoseiid mites.
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Ácaros , Femenino , Animales , Ácaros/genética , Antioxidantes , Proteínas Quinasas Activadas por Mitógenos/genética , Temperatura , Frío , Conducta Predatoria , Control Biológico de Vectores/métodosRESUMEN
BACKGROUND: Taxol from Taxus species is a precious drug used for the treatment of cancer and can effectively inhibit the proliferation of cancer cells. However, the growth of Taxus plants is very slow and the content of taxol is quite low. Therefore, it is of great significance to improve the yield of taxol by modern biotechnology without destroying the wild forest resources. Endophytic fungus which symbiosis with their host plants can promote the growth and secondary metabolism of medicinal plants. RESULTS: Here, an endophytic fungus KL27 was isolated from T. chinensis, and identified as Pseudodidymocyrtis lobariellae. The fermentation broth of KL27 (KL27-FB) could significantly promote the accumulation of taxol in needles of T. chinensis, reaching 0.361 ± 0.082 mg/g·DW (dry weight) at 7 days after KL27-FB treatment, which is 3.26-fold increase as compared to the control. The RNA-seq and qRT-PCR showed that KL27-FB could significantly increase the expression of key genes involved in the upstream pathway of terpene synthesis (such as DXS and DXR) and those in the taxol biosynthesis pathway (such as GGPPS, TS, T5OH, TAT, T10OH, T14OH, T2OH, TBT, DBAT and PAM), especially at the early stage of the stimulation. Moreover, the activation of jasmonic acid (JA) biosynthesis and JA signal transduction, and its crosstalk with other hormones, such as gibberellin acid (GA), ethylene (ET) and salicylic acid (SA), explained the elevation of most of the differential expressed genes related to taxol biosynthesis pathway. Moreover, TF (transcriptional factor)-encoding genes, including MYBs, ethylene-responsive transcription factors (ERFs) and basic/helix-loop-helix (bHLH), were detected as differential expressed genes after KL27-FB treatment, further suggested that the regulation of hormone signaling on genes of taxol biosynthesis was mediated by TFs. CONCLUSIONS: Our results indicated that fermentation broth of endophytic fungus KL27-FB could effectively enhance the accumulation of taxol in T. chinensis needles by regulating the phytohormone metabolism and signal transduction and further up-regulating the expression of multiple key genes involved in taxol biosynthesis. This study provides new insight into the regulatory mechanism of how endophytic fungus promotes the production and accumulation of taxol in Taxus sp.
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Ascomicetos/fisiología , Endófitos/fisiología , Regulación de la Expresión Génica de las Plantas , Paclitaxel/biosíntesis , Reguladores del Crecimiento de las Plantas/metabolismo , Transducción de Señal , Taxus/metabolismo , Genes de Plantas , Paclitaxel/metabolismo , Taxus/microbiología , Regulación hacia ArribaRESUMEN
Owing to multiple antibiotic resistance, Pseudomonas aeruginosa causes the most intractable infections to human beings worldwide, thus exploring novel drugs to defend against this bacterium remains of great importance. In this study, we purified a novel cochlioquinone B derivative (CoB1) from Salvia miltiorrhiza endophytic Bipolaris sorokiniana and reveal its role in host defense against P. aeruginosa infection by activating cytoprotective autophagy in alveolar macrophages (AMs) both in vivo and in vitro. Using a P. aeruginosa infection model, we observed that CoB1-treated mice manifest weakened lung injury, reduced bacterial systemic dissemination, decreased mortality, and dampened inflammatory responses, compared with the wild type littermates. We demonstrate that CoB1-induced autophagy in mouse AMs is associated with decreased PAK1 expression via the ubiquitination-mediated degradation pathway. The inhibition of PAK1 decreases the phosphorylation level of Akt, blocks the Akt/mTOR signaling pathway, and promotes the release of ULK1/2-Atg13-FIP200 complex from mTOR to initiate autophagosome formation, resulting in increased bacterial clearance capacity. Together, our results provide a molecular basis for the use of CoB1 to regulate host immune responses against P. aeruginosa infection and indicate that CoB1 is a potential option for the treatment of infection diseases.
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Autofagia/efectos de los fármacos , Benzoquinonas/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Quinasas p21 Activadas/metabolismo , Animales , Células Cultivadas , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Ratones , Ratones Endogámicos C57BL , Infecciones por Pseudomonas/metabolismo , Transducción de Señal/efectos de los fármacos , Ubiquitinación/efectos de los fármacosRESUMEN
SUMOylation, the covalent attachment of the small ubiquitin-like modifier (SUMO) to target proteins, is emerging as a key modulator of eukaryotic immune function. In plants, a SUMO1/2-dependent process has been proposed to control the deployment of host defense responses. The molecular mechanism underpinning this activity remains to be determined, however. Here we show that increasing nitric oxide levels following pathogen recognition promote S-nitrosylation of the Arabidopsis SUMO E2 enzyme, SCE1, at Cys139. The SUMO-conjugating activities of both SCE1 and its human homolog, UBC9, were inhibited following this modification. Accordingly, mutation of Cys139 resulted in increased levels of SUMO1/2 conjugates, disabled immune responses, and enhanced pathogen susceptibility. Our findings imply that S-nitrosylation of SCE1 at Cys139 enables NO bioactivity to drive immune activation by relieving SUMO1/2-mediated suppression. The control of global SUMOylation is thought to occur predominantly at the level of each substrate via complex local machineries. Our findings uncover a parallel and complementary mechanism by suggesting that total SUMO conjugation may also be regulated directly by SNO formation at SCE1 Cys139. This Cys is evolutionary conserved and specifically S-nitrosylated in UBC9, implying that this immune-related regulatory process might be conserved across phylogenetic kingdoms.
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Proteínas de Arabidopsis/inmunología , Arabidopsis/inmunología , Cisteína Endopeptidasas/inmunología , Óxido Nítrico/inmunología , Enzimas Ubiquitina-Conjugadoras/inmunología , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cisteína Endopeptidasas/genética , Humanos , Óxido Nítrico/genética , Enzimas Ubiquitina-Conjugadoras/genéticaRESUMEN
BACKGROUND: Allium sativum (garlic) is an economically important food source and medicinal plant rich in sulfides and other protective substances such as alliin, the precursor of allicin biosynthesis. Cysteine, serine and sulfur is the precursor of alliin biosynthesis. However, little is known about the alliin content under abiotic stress or the mechanism by which it is synthesized. RESULTS: The findings revealed that the content of alliin was lowest in the garlic roots, and highest in the buds. Furthermore, alliin levels decreased in mature leaves following wounding. Transcriptome data generated over time after wounding further revealed significant up-regulation of genes integral to the biosynthetic pathways of cysteine and serine in mature garlic leaves. CONCLUSIONS: The findings suggest that differential expression of cysteine, serine and sulfide-related genes underlies the accumulation of alliin and its precursors in garlic, providing a basis for further analyses of alliin biosynthesis.
Asunto(s)
Cisteína/análogos & derivados , Ajo/genética , Expresión Génica , Hojas de la Planta/fisiología , Cisteína/biosíntesis , SulfóxidosRESUMEN
An efficient reactive oxygen species (ROS) detoxification system is vital for the survival of the pathogenic fungus Aspergillus fumigatus within the host high-ROS environment of the host. Therefore, identifying and targeting factors essential for oxidative stress response is one approach to developing novel treatments for fungal infections. The oxidation resistance 1 (Oxr1) protein is essential for protection against oxidative stress in mammals, but its functions in pathogenic fungi remain unknown. The present study aimed to characterize the role of an Oxr1 homolog in A. fumigatus. The results indicated that the OxrA protein plays an important role in oxidative stress resistance by regulating the catalase function in A. fumigatus, and overexpression of catalase can rescue the phenotype associated with OxrA deficiency. Importantly, the deficiency of oxrA decreased the virulence of A. fumigatus and altered the host immune response. Using the Aspergillus-induced lung infection model, we demonstrated that the ΔoxrA mutant strain induced less tissue damage along with decreased levels of lactate dehydrogenase (LDH) and albumin release. Additionally, the ΔoxrA mutant caused inflammation at a lower degree, along with a markedly reduced influx of neutrophils to the lungs and a decreased secretion of cytokine usually associated with recruitment of neutrophils in mice. These results characterize the role of OxrA in A. fumigatus as a core regulator of oxidative stress resistance and fungal pathogenesis. IMPORTANCE Knowledge of ROS detoxification in fungal pathogens is useful in the design of new antifungal drugs and could aid in the study of oxidative stress resistance mechanisms. In this study, we demonstrate that OxrA protein localizes to the mitochondria and functions to protect against oxidative damage. We demonstrate that OxrA contributes to oxidative stress resistance by regulating catalase function, and overexpression of catalase (CatA or CatB) can rescue the phenotype that is associated with OxrA deficiency. Remarkably, a loss of OxrA attenuated the fungal virulence in a mouse model of invasive pulmonary aspergillosis and altered the host immune response. Therefore, our finding indicates that inhibition of OxrA might be an effective approach for alleviating A. fumigatus infection. The present study is, to the best of our knowledge, a pioneer in reporting the vital role of Oxr1 protein in pathogenic fungi.
Asunto(s)
Aspergilosis , Aspergillus fumigatus , Proteínas Fúngicas/metabolismo , Estrés Oxidativo , Animales , Aspergillus fumigatus/enzimología , Aspergillus fumigatus/patogenicidad , Catalasa , Ratones , Especies Reactivas de Oxígeno , VirulenciaRESUMEN
Nitric oxide (NO) regulates the deployment of a phalanx of immune responses, chief among which is the activation of a constellation of defence-related genes. However, the underlying molecular mechanisms remain largely unknown. The Arabidopsis thaliana zinc finger transcription factor (ZF-TF), S-nitrosothiol (SNO) Regulated 1 (SRG1), is a central target of NO bioactivity during plant immunity. Here we characterize the remaining members of the SRG gene family. Both SRG2 and, especially, SRG3 were positive regulators of salicylic acid-dependent plant immunity. Analysis of SRG single, double and triple mutants implied that SRG family members have additive functions in plant immunity and, surprisingly, are under reciprocal regulation. SRG2 and SRG3 localized to the nucleus and functioned as ethylene-responsive element binding factor-associated amphiphilic repression (EAR) domain-dependent transcriptional repressors: NO abolished this activity for SRG3 but not for SRG2. Consistently, loss of GSNOR function, resulting in increased (S)NO concentrations, fully suppressed the disease resistance phenotype established from SRG3 but not SRG2 overexpression. Remarkably, SRG3 but not SRG2 was S-nitrosylated in vitro and in vivo. Our findings suggest that the SRG family has separable functions in plant immunity, and, surprisingly, these ZF-TFs exhibit reciprocal regulation. It is remarkable that, through neofunctionalization, the SRG family has evolved to become differentially regulated by the key immune-related redox cue, NO.
Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Óxido Nítrico/metabolismo , Inmunidad de la Planta , Dedos de ZincRESUMEN
Gastric cancer is one of the most common malignant tumors in the world, and prevention through diet is one of the ways to control. Houttuynia cordata thunb.(HCT) is a plant having medicine and food function, has many biological properties. However, the effect of food style on the anticancer activity of HCT is not clear. So, we investigate the effect of heat treatment on anticancer activity of HCT. HCT extracts (heated aerial stem, heated subterraneous stem, heated leaves defined as HAS, HSS, HL, respectively, and not heated defined as NAS, NSS, NL, respectively) were obtained, and their inhibited activity were detected by alamar blue assay. The cell apoptosis was detected by DAPI staining and flow cytometry analysis. Western blot was performed to test the expression of apoptotic related protein. HCT showed the anticancer activity in four human tumor cell lines. Interestingly, heat treatment could increase the anticancer activity. In SCG-7901 cells, heat treatment increased anticancer activity of AS by 2-14 folds and induced apoptosis through regulating the intrinsic signaling pathways. Intriguingly, the caspase nine specific inhibitor blocked AS-reduced cell viability. Heat treatment increased the anticancer activity of HCT, and can be used as a dietary style for prevention of gastric cancer.