Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 172
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
PLoS Pathog ; 20(1): e1011913, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38166144

RESUMO

Mycotoxin deoxynivalenol (DON) produced by the Fusarium graminearum complex is highly toxic to animal and human health. During DON synthesis, the endoplasmic reticulum (ER) of F. graminearum is intensively reorganized, from thin reticular structure to thickened spherical and crescent structure, which was referred to as "DON toxisome". However, the underlying mechanism of how the ER is reorganized into toxisome remains unknown. In this study, we discovered that overproduction of ER-localized DON biosynthetic enzyme Tri4 or Tri1, or intrinsic ER-resident membrane proteins FgHmr1 and FgCnx was sufficient to induce toxisome-shaped structure (TSS) formation under non-toxin-inducing conditions. Moreover, heterologous overexpression of Tri1 and Tri4 proteins in non-DON-producing fungi F. oxysporum f. sp. lycopersici and F. fujikuroi also led to TSS formation. In addition, we found that the high osmolarity glycerol (HOG), but not the unfolded protein response (UPR) signaling pathway was involved in the assembly of ER into TSS. By using toxisome as a biomarker, we screened and identified a novel chemical which exhibited high inhibitory activity against toxisome formation and DON biosynthesis, and inhibited Fusarium growth species-specifically. Taken together, this study demonstrated that the essence of ER remodeling into toxisome structure is a response to the overproduction of ER-localized DON biosynthetic enzymes, providing a novel pathway for management of mycotoxin contamination.


Assuntos
Fusarium , Micotoxinas , Tricotecenos , Humanos , Micotoxinas/metabolismo , Fusarium/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Retículo Endoplasmático/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(28): e2302226120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37399403

RESUMO

Plant intracellular nucleotide-binding domain, leucine-rich repeat-containing receptors (NLRs) activate a robust immune response upon detection of pathogen effectors. How NLRs induce downstream immune defense genes remains poorly understood. The Mediator complex plays a central role in transducing signals from gene-specific transcription factors to the transcription machinery for gene transcription/activation. In this study, we demonstrate that MED10b and MED7 of the Mediator complex mediate jasmonate-dependent transcription repression, and coiled-coil NLRs (CNLs) in Solanaceae modulate MED10b/MED7 to activate immunity. Using the tomato CNL Sw-5b, which confers resistance to tospovirus, as a model, we found that the CC domain of Sw-5b directly interacts with MED10b. Knockout/down of MED10b and other subunits including MED7 of the middle module of Mediator activates plant defense against tospovirus. MED10b was found to directly interact with MED7, and MED7 directly interacts with JAZ proteins, which function as transcriptional repressors of jasmonic acid (JA) signaling. MED10b-MED7-JAZ together can strongly repress the expression of JA-responsive genes. The activated Sw-5b CC interferes with the interaction between MED10b and MED7, leading to the activation of JA-dependent defense signaling against tospovirus. Furthermore, we found that CC domains of various other CNLs including helper NLR NRCs from Solanaceae modulate MED10b/MED7 to activate defense against different pathogens. Together, our findings reveal that MED10b/MED7 serve as a previously unknown repressor of jasmonate-dependent transcription repression and are modulated by diverse CNLs in Solanaceae to activate the JA-specific defense pathways.


Assuntos
Proteínas de Arabidopsis , Imunidade Vegetal , Imunidade Vegetal/genética , Ciclopentanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Complexo Mediador/genética , Complexo Mediador/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
3.
Nature ; 573(7772): 83-86, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31485059

RESUMO

Quasars, which are exceptionally bright objects at the centres (or nuclei) of galaxies, are thought to be produced through the accretion of gas into disks surrounding supermassive black holes1-3. There is observational evidence at galactic and circumnuclear scales4 that gas flows inwards towards accretion disks around black holes, and such an inflow has been measured at the scale of the dusty torus that surrounds the central accretion disk5. At even smaller scales, inflows close to an accretion disk have been suggested to explain the results of recent modelling of the response of gaseous broad emission lines to continuum variations6,7. However, unambiguous observations of inflows that actually reach accretion disks have been elusive. Here we report the detection of redshifted broad absorption lines of hydrogen and helium atoms in a sample of quasars. The lines show broad ranges of Doppler velocities that extend continuously from zero to redshifts as high as about 5,000 kilometres per second. We interpret this as the inward motion of gases at velocities comparable to freefall speeds close to the black hole, constraining the fastest infalling gas to within 10,000 gravitational radii of the black hole (the gravitational radius being the gravitational constant multiplied by the object mass, divided by the speed of light squared). Extensive photoionization modelling yields a characteristic radial distance of the inflow of approximately 1,000 gravitational radii, possibly overlapping with the outer accretion disk.

4.
Plant J ; 114(6): 1490-1505, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36971060

RESUMO

Australian pine (Casuarina spp.) is extensively planted in tropical and subtropical regions for wood production, shelterbelts, environmental protection, and ecological restoration due to their superior biological characteristics, such as rapid growth, wind and salt tolerance, and nitrogen fixation. To analyze the genomic diversity of Casuarina, we sequenced the genomes and constructed de novo genome assemblies of the three most widely planted Casuarina species: C. equisetifolia, C. glauca, and C. cunninghamiana. We generated chromosome-scale genome sequences using both Pacific Biosciences (PacBio) Sequel sequencing and chromosome conformation capture technology (Hi-C). The total genome sizes for C. equisetifolia, C. glauca, and C. cunninghamiana are 268 942 579 bp, 296 631 783 bp, and 293 483 606 bp, respectively, of which 25.91, 27.15, and 27.74% were annotated as repetitive sequences. We annotated 23 162, 24 673, and 24 674 protein-coding genes in C. equisetifolia, C. glauca, and C. cunninghamiana, respectively. We then collected branchlets from male and female individuals for whole-genome bisulfite sequencing (BS-seq) to explore the epigenetic regulation of sex determination in these three species. Transcriptome sequencing (RNA-seq) revealed differential expression of phytohormone-related genes between male and female plants. In summary, we generated three chromosome-level genome assemblies and comprehensive DNA methylation and transcriptome datasets from both male and female material for three Casuarina species, providing a basis for the comprehensive investigation of genomic diversity and functional gene discovery of Casuarina in the future.


Assuntos
Cromossomos , Epigênese Genética , Austrália , Sequência de Bases , Sequências Repetitivas de Ácido Nucleico , Anotação de Sequência Molecular
5.
Plant Physiol ; 191(2): 1017-1035, 2023 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-36417282

RESUMO

The fast growth of Moso bamboo (Phyllostachys edulis) shoots is caused by the rapid elongation of each internode. However, the key underlying cellular processes and epigenetic mechanisms remain largely unexplored. We used microscopy and multi-omics approaches to investigate two regions (bottom and middle) of the 18th internode from shoots of two different heights (2 and 4 m). We observed that internode cells become longer, and that lignin biosynthesis and glycosyltransferase family 43 (GT43) genes are substantially upregulated with shoot height. Nanopore direct RNA sequencing (DRS) revealed a higher N6-methyladenine (m6A) modification rate in 2-m shoots than in 4-m shoots. In addition, different specific m6A modification sites were enriched at different growth stages. Global DNA methylation profiling indicated that DNA methylation levels are higher in 4-m shoots than in 2-m shoots. We also detected shorter poly(A) tail lengths (PALs) in 4-m shoots compared with 2-m shoots. Genes showing differential PAL were mainly enriched in the functional terms of protein translation and vesicle fusion. An association analysis between PALs and DNA methylation strongly suggested that gene body CG methylation levels are positively associated with PAL. This study provides valuable information to better understand post-transcriptional regulations responsible for fast-growing shoots in Moso bamboo.


Assuntos
Regulação da Expressão Gênica de Plantas , Poaceae , Brotos de Planta/metabolismo , Poaceae/genética , RNA/metabolismo , Epigênese Genética
6.
Cell Biochem Funct ; 42(1): e3896, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38081793

RESUMO

Cysteine and glycine-rich protein 2 (Csrp2) has emerged as a key factor in controlling the phenotypic modulation of smooth muscle cells. The phenotypic transition of airway smooth muscle cells (ASMCs) is a pivotal step in developing airway remodeling during the onset of asthma. However, whether Csrp2 mediates the phenotypic transition of ASMCs in airway remodeling during asthma onset is undetermined. This work aimed to address the link between Csrp2 and the phenotypic transition of ASMCs evoked by platelet-derived growth factor (PDGF)-BB in vitro. The overexpression or silencing of Csrp2 in ASMCs was achieved through adenovirus-mediated gene transfer. The expression of mRNA was measured by quantitative real-time-PCR. Protein levels were determined through Western blot analysis. Cell proliferation was detected by EdU assay and Calcein AM assays. Cell cycle distribution was assessed via fluorescence-activated cell sorting assay. Cell migration was evaluated using the scratch-wound assay. The transcriptional activity of Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ) was measured using the luciferase reporter assay. A decline in Csrp2 level occurred in PDGF-BB-stimulated ASMCs. Increasing Csrp2 expression repressed the PDGF-BB-evoked proliferation and migration of ASMCs. Moreover, increasing Csrp2 expression impeded the phenotypic change of PDGF-BB-stimulated ASMCs from a contractile phenotype into a synthetic/proliferative phenotype. On the contrary, the opposite effects were observed in Csrp2-silenced ASMCs. The activity of YAP/TAZ was elevated in PDGF-BB-stimulated ASMCs, which was weakened by Csrp2 overexpression or enhanced by Csrp2 silencing. The YAP/TAZ activator could reverse Csrp2-overexpression-mediated suppression of the PDGF-BB-evoked phenotypic switching of ASMCs, while the YAP/TAZ suppressor could dimmish Csrp2-silencing-mediated enhancement on PDGF-BB-evoked phenotypic switching of ASMCs. In summary, Csrp2 serves as a determinant for the phenotypic switching of ASMCs. Increasing Csrp2 is able to impede PDGF-BB-evoked phenotypic change of ASMCs from a synthetic phenotype into a synthetic/proliferative phenotype through the effects on YAP/TAZ. This work implies that Csrp2 may be a key player in airway remodeling during the onset of asthma.


Assuntos
Asma , Cisteína , Humanos , Becaplermina/genética , Becaplermina/metabolismo , Cisteína/genética , Cisteína/metabolismo , Remodelação das Vias Aéreas , Células Cultivadas , Miócitos de Músculo Liso/metabolismo , Proliferação de Células , Asma/metabolismo , Fenótipo , Movimento Celular
7.
Biol Res ; 57(1): 36, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822414

RESUMO

BACKGROUND: Helicase for meiosis 1 (HFM1), a putative DNA helicase expressed in germ-line cells, has been reported to be closely associated with premature ovarian insufficiency (POI). However, the underlying molecular mechanism has not been clearly elucidated. The aim of this study was to investigate the function of HFM1 in the first meiotic prophase of mouse oocytes. RESULTS: The results suggested that the deficiency of HFM1 resulting in increased apoptosis and depletion of oocytes in mice, while the oocytes were arrested in the pachytene stage of the first meiotic prophase. In addition, impaired DNA double-strand break repair and disrupted synapsis were observed in the absence of HFM1. Further investigation revealed that knockout of HFM1 promoted ubiquitination and degradation of FUS protein mediated by FBXW11. Additionally, the depletion of HFM1 altered the intranuclear localization of FUS and regulated meiotic- and oocyte development-related genes in oocytes by modulating the expression of BRCA1. CONCLUSIONS: These findings elaborated that the critical role of HFM1 in orchestrating the regulation of DNA double-strand break repair and synapsis to ensure meiosis procession and primordial follicle formation. This study provided insights into the pathogenesis of POI and highlighted the importance of HFM1 in maintaining proper meiotic function in mouse oocytes.


Assuntos
Prófase Meiótica I , Oócitos , Ubiquitinação , Animais , Feminino , Camundongos , Apoptose/fisiologia , Quebras de DNA de Cadeia Dupla , Reparo do DNA/fisiologia , Meiose/fisiologia , Prófase Meiótica I/fisiologia , Camundongos Knockout , Oócitos/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Proteína FUS de Ligação a RNA/genética
8.
Proc Natl Acad Sci U S A ; 118(1)2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33372152

RESUMO

Defense of the central nervous system (CNS) against infection must be accomplished without generation of potentially injurious immune cell-mediated or off-target inflammation which could impair key functions. As the CNS is an immune-privileged compartment, inducible innate defense mechanisms endogenous to the CNS likely play an essential role in this regard. Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide known to regulate neurodevelopment, emotion, and certain stress responses. While PACAP is known to interact with the immune system, its significance in direct defense of brain or other tissues is not established. Here, we show that our machine-learning classifier can screen for immune activity in neuropeptides, and correctly identified PACAP as an antimicrobial neuropeptide in agreement with previous experimental work. Furthermore, synchrotron X-ray scattering, antimicrobial assays, and mechanistic fingerprinting provided precise insights into how PACAP exerts antimicrobial activities vs. pathogens via multiple and synergistic mechanisms, including dysregulation of membrane integrity and energetics and activation of cell death pathways. Importantly, resident PACAP is selectively induced up to 50-fold in the brain in mouse models of Staphylococcus aureus or Candida albicans infection in vivo, without inducing immune cell infiltration. We show differential PACAP induction even in various tissues outside the CNS, and how these observed patterns of induction are consistent with the antimicrobial efficacy of PACAP measured in conditions simulating specific physiologic contexts of those tissues. Phylogenetic analysis of PACAP revealed close conservation of predicted antimicrobial properties spanning primitive invertebrates to modern mammals. Together, these findings substantiate our hypothesis that PACAP is an ancient neuro-endocrine-immune effector that defends the CNS against infection while minimizing potentially injurious neuroinflammation.


Assuntos
Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/fisiologia , Sequência de Aminoácidos/genética , Animais , Anti-Infecciosos/metabolismo , Peptídeos Catiônicos Antimicrobianos/metabolismo , Encéfalo/imunologia , Encéfalo/metabolismo , Morte Celular/efeitos dos fármacos , Simulação por Computador , Bases de Dados Genéticas , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Neuropeptídeos/metabolismo , Filogenia , Transdução de Sinais/fisiologia
9.
Arch Gynecol Obstet ; 309(2): 457-467, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37264272

RESUMO

PURPOSE: The aim of this systematic review and meta-analysis is to evaluate the efficacy of stem cell therapy in mouse models of POI and patients with POI. METHODS: The PubMed, Web of Science, and Embase databases were searched from inception to February 2022 for relevant animal and clinical studies. The reference lists of the included reviews were manually searched to identify additional eligible studies. Data were independently extracted by two investigators, and disagreements were resolved by discussion. SYRCLE's risk of bias tool and the MINORS tool were used to assess the quality of animal and clinical studies by two independent investigators. All statistical analyses were conducted using Review Manager 5.3 software. RESULTS: A total of twenty animal studies and six clinical studies were included in this meta-analysis. In animal studies, the results showed that stem cells could improve hormone levels, follicle count, estrous cycle and pregnancy outcome. For hormone levels, stem cells increased serum E2 and AMH levels and decreased serum FSH and LH levels compared with the control group (serum E2 level: SMD: 5.05, 95% CI 4.21-5.90, P < 0.00001; serum AMH level: SMD: 4.42, 95% CI 3.06-5.79, P < 0.00001; serum FSH level: SMD: - 3.79, 95% CI - 4.87 to -  2.70, P < 0.00001; serum LH level: SMD: - 1.31, 95% CI - 1.65 to - 0.96, P < 0.00001). All follicle counts, except for the antral follicle count, were significantly changed compared with the control group. (primordial follicle count: SMD: 4.61, 95% CI 3.65-5.56, P < 0.00001; primary follicle count: SMD: 3.35, 95% CI 1.08-5.63, P = 0.004; secondary follicle count: SMD: 3.23, 95% CI 1.92-4.55, P < 0.00001; total follicle count: SMD: 4.84, 95% CI 2.86-6.83, P < 0.00001; oocyte count: SMD: 7.56, 95% CI 5.92-9.20, P < 0.00001; atretic follicle count: SMD: - 1.79, 95% CI - 2.59 to - 1.00, P < 0.00001). For the estrous cycle, stem cell therapy increased the number of estrous cycles (WMD: 2.72, 95% CI 2.07-3.37, P < 0.00001) and decreased the duration of the estrous cycle (WMD: - 1.26, 95% CI - 1.84 to - 0.69, P < 0.0001) compared with the control group. For pregnancy outcomes, stem cell therapy increased the fertility rate (RR: 3.00, 95% CI 1.74-5.17, P < 0.0001) and litter size (WMD: 3.82, 95% CI 0.36-7.28, P = 0.03) compared with the control group. In animal studies, the asymmetric funnel plot of serum E2 and FSH levels indicated the possibility of publication bias. Unpublished and negative studies may be the source of publication bias. In clinical studies, the results showed that stem cell therapy could decrease serum FSH level (MD: - 30.32, 95% CI - 59.03 to - 1.01, P = 0.04) and increase AFC (MD: 1.07, 95% CI 0.70-1.43, P < 0.00001), pregnancy rate (RD: 0.19, 95% CI 0.04-0.34, P = 0.01) and live birth rate (RD: 0.19, 95% CI 0.07-0.31, P = 0.001) in POI patients. In addition, there was no significant difference in menstrual function regained (RD: 0.22, 95% CI - 0.03-0.46, P = 0.09), oocytes retrieved (MD: 1.00, 95% CI - 0.64-2.64, P = 0.23) and embryos (MD: 0.80, 95% CI - 0.15-1.76, P = 0.10) between different groups. CONCLUSION: This meta-analysis suggested that stem cell therapy might be effective in POI mouse models and patients and could be considered a potential treatment to restore fertility capability in POI patients.


Assuntos
Resultado da Gravidez , Insuficiência Ovariana Primária , Feminino , Animais , Camundongos , Gravidez , Humanos , Insuficiência Ovariana Primária/terapia , Folículo Ovariano/metabolismo , Hormônio Foliculoestimulante , Terapia Baseada em Transplante de Células e Tecidos
10.
Pestic Biochem Physiol ; 190: 105311, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36740345

RESUMO

The calcium-calcineurin and high-osmolarity glycerol (HOG) pathways play crucial roles in fungal development, pathogenicity, and in responses to various environmental stresses. However, interaction of these pathways in regulating fungicide sensitivity remains largely unknown in phytopathogenic fungi. In this study, we investigated the function of the calcium-calcineurin signalling pathway in Fusarium graminearum, the causal agent of Fusarium head blight. Inhibitors of Ca2+ and calcineurin enhanced antifungal activity of tebuconazole (an azole fungicide) against F. graminearum. Deletion of the putative downstream transcription factor FgCrz1 resulted in significantly increased sensitivity of F. graminearum to tebuconazole. FgCrz1-GFP was translocated to the nucleus upon tebuconazole treatment in a calcineurin-dependent manner. In addition, deletion of FgCrz1 increased the phosphorylation of FgHog1 in response to tebuconazole. Moreover, the calcium-calcineurin and HOG signalling pathways exhibited synergistic effect in regulating pathogenicity and sensitivity of F. graminearum to tebuconazole and multiple other stresses. RNA-seq data revealed that FgCrz1 regulated expression of a set of non-CYP51 genes that are associated with tebuconazole sensitivity, including multidrug transporters, membrane lipid biosynthesis and metabolism, and cell wall organization. Our findings demonstrate that the calcium-calcineurin and HOG pathways act coordinately to orchestrate tebuconazole sensitivity and pathogenicity in F. graminearum, which may provide novel insights in management of Fusarium disease.


Assuntos
Fungicidas Industriais , Fusarium , Glicerol/metabolismo , Cálcio/metabolismo , Fungicidas Industriais/farmacologia , Fungicidas Industriais/metabolismo , Calcineurina/genética , Calcineurina/metabolismo , Calcineurina/farmacologia , Virulência/genética , Concentração Osmolar , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Doenças das Plantas/microbiologia
11.
Drug Dev Res ; 84(6): 1037-1071, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37195405

RESUMO

Cell-penetrating peptides (CPPs), first identified in HIV a few decades ago, deserved great attention in the last two decades; especially to support the penetration of anticancer drug means. In the drug delivery discipline, they have been involved in various approaches from mixing with hydrophobic drugs to the use of genetically conjugated proteins. The early classification as cationic and amphipathic CPPs has been extended to a few more classes such as hydrophobic and cyclic CPPs so far. Developing potential sequences utilized almost all methods of modern science: choosing high-efficiency peptides from natural protein sequences, sequence-based comparison, amino acid substitution, obtaining chemical and/or genetic conjugations, in silico approaches, in vitro analysis, animal experiments, etc. The bottleneck effect in this discipline reveals the complications that modern science faces in drug delivery research. Most CPP-based drug delivery systems (DDSs) efficiently inhibited tumor volume and weight in mice, but only in rare cases reduced their levels and continued further processes. The integration of chemical synthesis into the development of CPPs made a significant contribution and even reached the clinical stage as a diagnostic tool. But constrained efforts still face serious problems in overcoming biobarriers to reach further achievements. In this work, we reviewed the roles of CPPs in anticancer drug delivery, focusing on their amino acid composition and sequences. As the most suitable point, we relied on significant changes in tumor volume in mice resulting from CPPs. We provide a review of individual CPPs and/or their derivatives in a separate subsection.


Assuntos
Antineoplásicos , Peptídeos Penetradores de Células , Neoplasias , Animais , Camundongos , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/metabolismo , Peptídeos Penetradores de Células/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sequência de Aminoácidos , Neoplasias/tratamento farmacológico
12.
J Environ Manage ; 325(Pt A): 116532, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36419281

RESUMO

Water conservation function is a critical terrestrial ecosystem service in providing water supply and achieving water security, which has raised concerns under the pressure of climate change. However, the knowledge of variance on multi-time scale, spatiotemporal dynamic, and ecosystem variance of water conservation is insufficient. In this paper, the annual, monthly, and daily scales of water conservation and the spatiotemporal pattern of monthly water conservation were estimated based on the SWAT model from 2010 to 2020 in the Heihe River Basin (HRB). Additionally, EOF (Empirical orthogonal function) analysis was conducted to decompose the time series of water conservation function distribution into temporal coefficients and spatial patterns. The HRB was categorized into six representative ecosystems with three slope grades to illustrate the variance of water conservation function. The annual water conservation depth (WC) slightly decreased (-10.36 mm/10a) from 2010 to 2020, the monthly WC was dominated by the effects of seasonal variation, and the daily WC was highly nonlinear. The high variability and importance region is mainly located in the upstream and the central area of midstream, which deserves more attention for ecological management and priority protection. Moreover, the forest ecosystem is of the highest resilience and great ecological significance, which increased risk of reduced water conservation under the lack of precipitation. Even in a forest-dominated basin, water conservation can be impacted by other ecosystems with the strong influence of human activities. Our results provide scientific evidence for the improvement of water conservation capacity and making the adapted land use policy in Yellow River basins.


Assuntos
Conservação dos Recursos Hídricos , Humanos , Ecossistema , Rios , Florestas , Mudança Climática
13.
Plant J ; 106(2): 435-453, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33506534

RESUMO

In mammals, DNA methylation is associated with aging. However, age-related DNA methylation changes during phase transitions largely remain unstudied in plants. Moso bamboo (Phyllostachys edulis) requires a very long time to transition from the vegetative to the floral phase. To comprehensively investigate the association of DNA methylation with aging, we present here single-base-resolution DNA methylation profiles using both high-throughput bisulfite sequencing and single-molecule nanopore-based DNA sequencing, covering the long period of vegetative growth and transition to flowering in moso bamboo. We discovered that CHH methylation gradually accumulates from vegetative to reproductive growth in a time-dependent fashion. Differentially methylated regions, correlating with chronological aging, occurred preferentially at both transcription start sites and transcription termination sites. Genes with CG methylation changes showed an enrichment of Gene Ontology (GO) categories in 'vegetative to reproductive phase transition of meristem'. Combining methylation data with mRNA sequencing revealed that DNA methylation in promoters, introns and exons may have different roles in regulating gene expression. Finally, circular RNA (circRNA) sequencing revealed that the flanking introns of circRNAs are hypermethylated and enriched in long terminal repeat (LTR) retrotransposons. Together, the observations in this study provide insights into the dynamic DNA methylation and circRNA landscapes, correlating with chronological age, which paves the way to study further the impact of epigenetic factors on flowering in moso bamboo.


Assuntos
Envelhecimento/genética , Metilação de DNA , Flores/crescimento & desenvolvimento , Poaceae/genética , RNA Circular/genética , RNA de Plantas/genética , Envelhecimento/fisiologia , Metilação de DNA/genética , Metilação de DNA/fisiologia , Elementos de DNA Transponíveis/genética , Elementos de DNA Transponíveis/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Estudo de Associação Genômica Ampla , Poaceae/crescimento & desenvolvimento , Poaceae/metabolismo , RNA Circular/metabolismo , RNA Circular/fisiologia , RNA de Plantas/metabolismo , RNA de Plantas/fisiologia , Análise de Sequência de DNA/métodos
14.
Proc Natl Acad Sci U S A ; 116(14): 6944-6953, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30877253

RESUMO

Diversity of α-helical host defense peptides (αHDPs) contributes to immunity against a broad spectrum of pathogens via multiple functions. Thus, resolving common structure-function relationships among αHDPs is inherently difficult, even for artificial-intelligence-based methods that seek multifactorial trends rather than foundational principles. Here, bioinformatic and pattern recognition methods were applied to identify a unifying signature of eukaryotic αHDPs derived from amino acid sequence, biochemical, and three-dimensional properties of known αHDPs. The signature formula contains a helical domain of 12 residues with a mean hydrophobic moment of 0.50 and favoring aliphatic over aromatic hydrophobes in 18-aa windows of peptides or proteins matching its semantic definition. The holistic α-core signature subsumes existing physicochemical properties of αHDPs, and converged strongly with predictions of an independent machine-learning-based classifier recognizing sequences inducing negative Gaussian curvature in target membranes. Queries using the α-core formula identified 93% of all annotated αHDPs in proteomic databases and retrieved all major αHDP families. Synthesis and antimicrobial assays confirmed efficacies of predicted sequences having no previously known antimicrobial activity. The unifying α-core signature establishes a foundational framework for discovering and understanding αHDPs encompassing diverse structural and mechanistic variations, and affords possibilities for deterministic design of antiinfectives.


Assuntos
Células Eucarióticas , Reconhecimento Automatizado de Padrão , Peptídeos/genética , Análise de Sequência de Proteína , Peptídeos/química , Estrutura Secundária de Proteína
15.
Sensors (Basel) ; 22(24)2022 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-36560070

RESUMO

A defense platform is usually based on two methods to make underwater acoustic warfare strategy decisions. One is through Monte-Carlo method online simulation, which is slow. The other is by typical empirical (database) and typical back-propagation (BP) neural network algorithms based on genetic algorithm (GA) optimization, which is less accurate and less robust. Therefore, this paper proposes a method to build an optimal underwater acoustic warfare feedback system using a three-layer GA-BP neural network and dropout processing of the neural network to prevent overfitting, so that the three-layer GA-BP neural network has adequate memory capability while still having suitable generalization capability. This method improves the accuracy and stability of the defense platform in making underwater acoustic warfare strategy decisions, thus increasing the survival probability of the defense platform in the face of incoming torpedoes. This paper uses the optimal underwater acoustic warfare strategies corresponding to incoming torpedoes with different postures as the sample set. Additionally, it uses a three-layer GA-BP neural network with an overfitting treatment for training. The prediction results have less error than the typical single-layer GA-BP neural network, and the survival probability of the defense platform improves by 6.15%. This defense platform underwater acoustic warfare strategy prediction method addresses the impact on the survival probability of the defense platform due to the decision speed and accuracy.


Assuntos
Algoritmos , Redes Neurais de Computação , Simulação por Computador , Acústica , Probabilidade
16.
Int J Mol Sci ; 23(22)2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36430463

RESUMO

Cunninghamia lanceolata (C. lanceolata) belongs to Gymnospermae, which are fast-growing and have desirable wood properties. However, C. lanceolata's stress resistance is little understood. To unravel the physiological and molecular regulation mechanisms under environmental stresses in the typical gymnosperm species of C. lanceolata, three-year-old plants were exposed to simulated drought stress (polyethylene glycol 8000), salicylic acid, and cold treatment at 4 °C for 8 h, 32 h, and 56 h, respectively. Regarding the physiological traits, we observed a decreased protein content and increased peroxidase upon salicylic acid and polyethylene glycol treatment. Superoxide dismutase activity either decreased or increased at first and then returned to normal under the stresses. Regarding the molecular regulation, we used both nanopore direct RNA sequencing and short-read sequencing to reveal a total of 5646 differentially expressed genes in response to different stresses, of which most had functions in lignin catabolism, pectin catabolism, and xylan metabolism, indicating that the development of stem-differentiating xylem was affected upon stress treatment. Finally, we identified a total of 51 AP2/ERF, 29 NAC, and 37 WRKY transcript factors in C. lanceolata. The expression of most of the NAC TFs increased under cold stress, and the expression of most of the WRKY TFs increased under cold and SA stress. These results revealed the transcriptomics responses in C. lanceolata to short-term stresses under this study's experimental conditions and provide preliminary clues about stem-differentiating xylem changes associated with different stresses.


Assuntos
Cunninghamia , Cunninghamia/genética , Perfilação da Expressão Gênica/métodos , Resposta ao Choque Frio/genética , Xilema/genética , Ácido Salicílico
17.
Molecules ; 27(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35744957

RESUMO

Cancer is one of the most serious human diseases, causing millions of deaths worldwide annually, and, therefore, it is one of the most investigated research disciplines. Developing efficient anticancer tools includes studying the effects of different natural enzymes of plant and microbial origin on tumor cells. The development of various smart delivery systems based on enzyme drugs has been conducted for more than two decades. Some of these delivery systems have been developed to the point that they have reached clinical stages, and a few have even found application in selected cancer treatments. Various biological, chemical, and physical approaches have been utilized to enhance their efficiencies by improving their delivery and targeting. In this paper, we review advanced delivery systems for enzyme drugs for use in cancer therapy. Their structure-based functions, mechanisms of action, fused forms with other peptides in terms of targeting and penetration, and other main results from in vivo and clinical studies of these advanced delivery systems are highlighted.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Humanos , Neoplasias/tratamento farmacológico , Peptídeos/uso terapêutico
18.
Plant Biotechnol J ; 19(11): 2164-2176, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34036713

RESUMO

Plants use intracellular nucleotide-binding leucine-rich repeat immune receptors (NLRs) to recognize pathogen-encoded effectors and initiate immune responses. Tomato spotted wilt virus (TSWV), which has been found to infect >1000 plant species, is among the most destructive plant viruses worldwide. The Sw-5b is the most effective and widely used resistance gene in tomato breeding to control TSWV. However, broad application of tomato cultivars carrying Sw-5b has resulted in an emergence of resistance-breaking (RB) TSWV. Therefore, new effective genes are urgently needed to prevent further RB TSWV outbreaks. In this study, we conducted artificial evolution to select Sw-5b mutants that could extend the resistance spectrum against TSWV RB isolates. Unlike regular NLRs, Sw-5b detects viral elicitor NSm using both the N-terminal Solanaceae-specific domain (SD) and the C-terminal LRR domain in a two-step recognition process. Our attempts to select gain-of-function mutants by random mutagenesis involving either the SD or the LRR of Sw-5b failed; therefore, we adopted a stepwise strategy, first introducing a NSmRB -responsive mutation at the R927 residue in the LRR, followed by random mutagenesis involving the Sw-5b SD domain. Using this strategy, we obtained Sw-5bL33P/K319E/R927A and Sw-5bL33P/K319E/R927Q mutants, which are effective against TSWV RB carrying the NSmC118Y or NSmT120N mutation, and against other American-type tospoviruses. Thus, we were able to extend the resistance spectrum of Sw-5b; the selected Sw-5b mutants will provide new gene resources to control RB TSWV.


Assuntos
Solanum lycopersicum , Tospovirus , Resistência à Doença/genética , Solanum lycopersicum/genética , Melhoramento Vegetal , Doenças das Plantas , Domínios Proteicos
19.
Respir Res ; 22(1): 238, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446024

RESUMO

BACKGROUND: Childhood asthma is a common respiratory disease characterized by airway inflammation. Tumor necrosis factor-α-induced protein 8-like 2 (TIPE2) has been found to be involved in the progression of asthma. This study aimed to explore the role of TIPE2 in the regulation of airway smooth muscle cells (ASMCs), which are one of the main effector cells in the development of asthma. MATERIALS AND METHODS: ASMCs were transfected with pcDNA3.0-TIPE2 or si-TIPE2 for 48 h and then treated with platelet-derived growth factor (PDGF)-BB. Cell proliferation of ASMCs was measured using the MTT assay. Cell migration of ASMCs was determined by a transwell assay. The mRNA expression levels of calponin and smooth muscle protein 22α (SM22α) were measured using qRT-PCR. The levels of TIPE2, calponin, SM22α, PI3K, p-PI3K, Akt, and p-Akt were detected by Western blotting. RESULTS: Our results showed that PDGF-BB treatment significantly reduced TIPE2 expression at both the mRNA and protein levels in ASMCs. Overexpression of TIPE2 inhibited PDGF-BB-induced ASMC proliferation and migration. In addition, overexpression of TIPE2 increased the expression of calponin and SM22α in PDGF-BB-stimulated ASMCs. However, an opposite effect was observed with TIPE2 knockdown. Furthermore, TIPE2 overexpression blocked PDGF-BB-induced phosphorylation of PI3K and Akt, whereas the expression of p-PI3K and p-Akt were aggravated by TIPE2 knockdown. Additionally, the effects of TIPE2 overexpression and TIPE2 knockdown were altered by IGF-1 and LY294002 treatments, respectively. CONCLUSIONS: Our findings demonstrate that TIPE2 inhibits PDGF-BB-induced ASMC proliferation, migration, and phenotype switching via the PI3K/Akt signaling pathway. Thus, TIPE2 may be a potential therapeutic target for the treatment of asthma.


Assuntos
Becaplermina/toxicidade , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Músculo Liso/metabolismo , Miócitos de Músculo Liso/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Remodelação das Vias Aéreas/efeitos dos fármacos , Remodelação das Vias Aéreas/fisiologia , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Fenótipo , Inibidores de Fosfoinositídeo-3 Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Traqueia/citologia , Traqueia/efeitos dos fármacos , Traqueia/metabolismo
20.
Gynecol Endocrinol ; 37(3): 246-250, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33274669

RESUMO

OBJECTIVE: Forkhead box P3 (FOXP3), a transcription factor, is regarding critical regulator of the function of regulatory T (Treg) cells and plays a crucial role in the development of autoimmune diseases. Premature ovarian insufficiency (POI) is an autoimmune disease; however, little is known about the association between FOXP3 variants and the susceptibility to POI. METHODS: Long-range polymerase chain reaction was used to analyze complete FOXP3 gene sequences from 153 patients with POI. The frequencies of genotypes and alleles of the FOXP3 gene were compared between patients with POI and 269 East Asian women from the Genome Aggregation (gnomAD) database. RESULTS: Forty-three single-nucleotide polymorphisms (SNPs) were detected, including 25 known SNPs and 18 novel SNPs. The genotype distributions and allele frequencies of two known SNPs (rs17847094 and rs76798919) and three novel SNPs (NC_000023.11:g.49112832G > A, NC_000023.11:g.49112833G > A, and NC_000023.11:g.49120479CT > C) were significantly different between the two groups. Linkage disequilibrium and haplotype analyses of the rs57734889, rs2232365, rs3761548, and rs34629506 SNPs in FOXP3 were performed and compared, and the high D' (standardized disequilibrium coefficients) value indicated that these polymorphisms may contribute to the risk of POI. CONCLUSIONS: This study is the first to show that genetic variants in the regulatory regions of FOXP3 play a vital role in idiopathic POI in the Chinese population.


Assuntos
Fatores de Transcrição Forkhead/genética , Insuficiência Ovariana Primária/genética , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Menopausa Precoce/etnologia , Menopausa Precoce/genética , Polimorfismo de Nucleotídeo Único , Insuficiência Ovariana Primária/epidemiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA