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Asymmetric cell divisions (ACDs) generate two daughter cells with identical genetic information but distinct cell fates through epigenetic mechanisms. However, the process of partitioning different epigenetic information into daughter cells remains unclear. Here, we demonstrate that the nucleosome remodeling and deacetylase (NuRD) complex is asymmetrically segregated into the surviving daughter cell rather than the apoptotic one during ACDs in Caenorhabditis elegans. The absence of NuRD triggers apoptosis via the EGL-1-CED-9-CED-4-CED-3 pathway, while an ectopic gain of NuRD enables apoptotic daughter cells to survive. We identify the vacuolar H+-adenosine triphosphatase (V-ATPase) complex as a crucial regulator of NuRD's asymmetric segregation. V-ATPase interacts with NuRD and is asymmetrically segregated into the surviving daughter cell. Inhibition of V-ATPase disrupts cytosolic pH asymmetry and NuRD asymmetry. We suggest that asymmetric segregation of V-ATPase may cause distinct acidification levels in the two daughter cells, enabling asymmetric epigenetic inheritance that specifies their respective life-versus-death fates.
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Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , ATPases Vacuolares Próton-Translocadoras , Caenorhabditis elegans/genética , Animais , ATPases Vacuolares Próton-Translocadoras/metabolismo , ATPases Vacuolares Próton-Translocadoras/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Divisão Celular Assimétrica , Apoptose , Epigênese Genética , Nucleossomos/metabolismoRESUMO
AlphaMissense identifies 23 million human missense variants as likely pathogenic, but only 0.1% have been clinically classified. To experimentally validate these predictions, chemical mutagenesis presents a rapid, cost-effective method to produce billions of mutations in model organisms. However, the prohibitive costs and limitations in the throughput of whole-genome sequencing (WGS) technologies, crucial for variant identification, constrain its widespread application. Here, we introduce a Tn5 transposase-assisted tagmentation technique for conducting WGS in Caenorhabditis elegans, Escherichia coli, Saccharomyces cerevisiae, and Chlamydomonas reinhardtii. This method, demands merely 20â min of hands-on time for a single-worm or single-cell clones and incurs a cost below 10 US dollars. It effectively pinpoints causal mutations in mutants defective in cilia or neurotransmitter secretion and in mutants synthetically sterile with a variant analogous to the B-Raf Proto-oncogene, Serine/Threonine Kinase (BRAF) V600E mutation. Integrated with chemical mutagenesis, our approach can generate and identify missense variants economically and efficiently, facilitating experimental investigations of missense variants in diverse species.
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Caenorhabditis elegans , Transposases , Sequenciamento Completo do Genoma , Animais , Caenorhabditis elegans/genética , Sequenciamento Completo do Genoma/métodos , Transposases/genética , Transposases/metabolismo , Chlamydomonas reinhardtii/genética , Saccharomyces cerevisiae/genética , Escherichia coli/genéticaRESUMO
BACKGROUND: Community-acquired pneumonia (CAP) is a common and serious condition that can be caused by a variety of pathogens. However, much remains unknown about how these pathogens interact with the lower respiratory commensals, and whether any correlation exists between the dysbiosis of the lower respiratory microbiota and disease severity and prognosis. METHODS: We conducted a retrospective cohort study to investigate the composition and dynamics of sputum microbiota in patients diagnosed with CAP. In total, 917 sputum specimens were collected consecutively from 350 CAP inpatients enrolled in six hospitals following admission. The V3-V4 region of the 16 S rRNA gene was then sequenced. RESULTS: The sputum microbiota in 71% of the samples were predominately composed of respiratory commensals. Conversely, 15% of the samples demonstrated dominance by five opportunistic pathogens. Additionally, 5% of the samples exhibited sterility, resembling the composition of negative controls. Compared to non-severe CAP patients, severe cases exhibited a more disrupted sputum microbiota, characterized by the highly dominant presence of potential pathogens, greater deviation from a healthy state, more significant alterations during hospitalization, and sparser bacterial interactions. The sputum microbiota on admission demonstrated a moderate prediction of disease severity (AUC = 0.74). Furthermore, different pathogenic infections were associated with specific microbiota alterations. Acinetobacter and Pseudomonas were more abundant in influenza A infections, with Acinetobacter was also enriched in Klebsiella pneumoniae infections. CONCLUSION: Collectively, our study demonstrated that pneumonia may not consistently correlate with severe dysbiosis of the respiratory microbiota. Instead, the degree of microbiota dysbiosis was correlated with disease severity in CAP patients.
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Infecções Comunitárias Adquiridas , Microbiota , Índice de Gravidade de Doença , Escarro , Humanos , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/epidemiologia , Masculino , Feminino , Escarro/microbiologia , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Estudos Longitudinais , Estudos de Coortes , Disbiose/microbiologia , Disbiose/diagnóstico , Pneumonia/microbiologia , Pneumonia/diagnóstico , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/epidemiologia , Idoso de 80 Anos ou mais , AdultoRESUMO
The greater yam (Dioscorea alata), a widely cultivated and nutritious food crop, suffers from widespread yield reduction due to anthracnose caused by Colletotrichum gloeosporioides. Latent infection often occurs before anthracnose phenotypes can be detected, making early prevention difficult and causing significant harm to agricultural production. Through comparative genomic analysis of 60 genomes of 38 species from the Colletotrichum genus, this study identified 17 orthologous gene groups (orthogroups) that were shared by all investigated C. gloeosporioides strains but absent from all other Colletotrichum species. Four of the 17 C. gloeosporioides-specific orthogroups were used as molecular markers for PCR primer designation and C. gloeosporioides detection. All of them can specifically detect C. gloeosporioides out of microbes within and beyond the Colletotrichum genus with different sensitivities. To establish a rapid, portable, and operable anthracnose diagnostic method suitable for field use, specific recombinase polymerase amplification (RPA) primer probe combinations were designed, and a lateral flow (LF)-RPA detection kit for C. gloeosporioides was developed, with the sensitivity reaching the picogram (pg) level. In conclusion, this study identified C. gloeosporioides-specific molecular markers and developed an efficient method for C. gloeosporioides detection, which can be applied to the prevention and control of yam anthracnose as well as anthracnose caused by C. gloeosporioides in other crops. The strategy adopted by this study also serves as a reference for the identification of molecular markers and diagnosis of other plant pathogens.
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The nucleosome remodeling and deacetylase (NuRD) complex is essential for gene expression and cell fate determination, and missense mutations of NuRD caused neurodevelopmental diseases. However, the molecular pathogenesis of clinic NuRD variants is unknown. Here, we introduced a clinic CHD3 (L915F) variant into Caenorhabditis elegans homologue LET-418, impairing germline and vulva development and ultimately causing animal sterility. Our ATAC-seq and RNA-seq analyses revealed that this variant generated an abnormal open chromatin structure and disrupted the expression of developmental genes. Through genetic suppressor screens, we uncovered that intragenic mutations, likely renovating NuRD activity, restored animal viability. We also found that intergenic mutations in nucleosome remodeling factor NURF that counteracts NuRD rescued abnormal chromatin structure, gene expression, and animal sterility. We propose that two antagonistic chromatin-remodeling factors coordinate to establish the proper chromatin status and transcriptome and that inhibiting NURF may provide insights for treatment of NuRD mutation-related diseases.
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Proteínas de Drosophila , Infertilidade , Animais , Feminino , Nucleossomos , Montagem e Desmontagem da Cromatina , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Cromatina , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Proteínas de Drosophila/metabolismo , Caenorhabditis elegans/metabolismoRESUMO
As a classic issue, structural seismic bearing capacity could not be accurately predicted since it was based on a structural ultimate state with inherent uncertainty. This result led to rare research efforts to discover structures' general and definite working laws from their experimental data. This study is to reveal the seismic working law of a bottom frame structure from its shaking table strain data by applying structural stressing state theory: (1) The tested strains are transformed into generalized strain energy density (GSED) values. (2) The method is proposed to express the stressing state mode and the corresponding characteristic parameter. (3) According to the natural law of quantitative and qualitative change, the Mann-Kendall criterion detects the mutation feature in the evolution of characteristic parameters versus seismic intensity. Moreover, it is verified that the stressing state mode also presents the corresponding mutation feature, which reveals the starting point in the seismic failure process of the bottom frame structure. (4) The Mann-Kendall criterion distinguishes the elastic-plastic branch (EPB) feature in the bottom frame structure's normal working process, which could be taken as the design reference. This study presents a new theoretical basis to determine the bottom frame structure's seismic working law and update the design code. Meanwhile, this study opens up the application of seismic strain data in structural analysis.
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In the original publication [...].
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Reducing carbon emissions in cities is crucial for addressing climate change, while the city-level emissions of different compositions and their relationships with socio-economic features remain largely unknown in China. Here, we explored the city-level emission pattern from the industrial, transportation, and household sectors and the emission intensity, as well as their associations with socio-economic features in China, using the up-to-date (2020) CO2 emissions based on 0.1° grid (10 × 10 km) emission data. The results show that: (1) CO2 emissions from the industrial sector were considerably dominant (78%), followed by indirect (10%), transportation (8%), and household (2%) emissions on the national scale; (2) combining total emissions with emission intensity, high emission-high intensity cities, which are the most noteworthy regions, were concentrated in the North, while low emission-low intensity types mainly occurred in the South-West; (3) cities with a higher GDP tend to emit more CO2, while higher-income cities tend to emit less CO2, especially from the household sector. Cities with a developed economy, as indicated by GDP and income, would have low emissions per GDP, representing a high emission efficiency. Reducing the proportion of the secondary sector of the economy could significantly decrease CO2 emissions, especially for industrial cities. Therefore, the carbon reduction policy in China should focus on the industrial cities in the North with high emission-high intensity performance. Increasing the income and proportion of the tertiary industry and encouraging compact cities can effectively reduce the total emissions during the economic development and urbanization process.
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Carbono , Desenvolvimento Econômico , Cidades , Carbono/análise , Dióxido de Carbono/análise , ChinaRESUMO
In this paper, a finite element model (FEM) is developed based on a set of circular steel tube reinforced concrete (CTRC) columns with axial compression and eccentric compression tests. The stressing state characteristics of the FEM are modeled in the form of characteristic pairs (mode-characteristic parameters) based on the structural stressing state theory and the proposed correlation modeling method. The slope increasing criterion is applied to the correlation characteristic parameter curve to obtain the characteristic point Q where the CTRC stressing state undergoes a qualitative change, and the characteristic point Q is defined as the new failure load point of the CTRC column. By selecting the element strain energy density at different locations of the FEM for correlation stressing state modeling and dividing the correlation stressing state sub-modes (concrete, steel tube, vertical reinforcement, and stirrup reinforcement), the structural stressing state theory and the rationality of the proposed correlation stressing state modeling method are verified. In addition, the certainty and reasonableness of the failure load points of the CTRC columns are revealed and verified.
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Rationale: Alteration of human respiratory microbiota had been observed in coronavirus disease (COVID-19). How the microbiota is associated with the prognosis in COVID-19 is unclear. Objectives: To characterize the feature and dynamics of the respiratory microbiota and its associations with clinical features in patients with COVID-19. Methods: We conducted metatranscriptome sequencing on 588 longitudinal oropharyngeal swab specimens collected from 192 patients with COVID-19 (including 39 deceased patients) and 95 healthy controls from the same geographic area. Meanwhile, the concentration of 27 cytokines and chemokines in plasma was measured for patients with COVID-19. Measurements and Main Results: The upper respiratory tract (URT) microbiota in patients with COVID-19 differed from that in healthy controls, whereas deceased patients possessed a more distinct microbiota, both on admission and before discharge/death. The alteration of URT microbiota showed a significant correlation with the concentration of proinflammatory cytokines and mortality. Specifically, Streptococcus-dominated microbiota was enriched in recovered patients, and showed high temporal stability and resistance against pathogens. In contrast, the microbiota in deceased patients was more susceptible to secondary infections and became more deviated from the norm after admission. Moreover, the abundance of S. parasanguinis on admission was significantly correlated with prognosis in nonsevere patients (lower vs. higher abundance, odds ratio, 7.80; 95% CI, 1.70-42.05). Conclusions: URT microbiota dysbiosis is a remarkable manifestation of COVID-19; its association with mortality suggests it may reflect the interplay between pathogens, symbionts, and the host immune status. Whether URT microbiota could be used as a biomarker for diagnosis and prognosis of respiratory diseases merits further investigation.
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COVID-19/microbiologia , COVID-19/mortalidade , Microbiota , Infecções Respiratórias/microbiologia , Infecções Respiratórias/mortalidade , Adulto , Idoso , COVID-19/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , SARS-CoV-2RESUMO
Cancers of the digestive system are malignant diseases. Our study focused on colon cancer, esophageal cancer (ESCC), rectal cancer, gastric cancer (GC), and rectosigmoid junction cancer to identify possible biomarkers for these diseases. The transcriptome data were downloaded from the TCGA database (The Cancer Genome Atlas Program), and a network was constructed using the WGCNA algorithm. Two significant modules were found, and coexpression networks were constructed. CytoHubba was used to identify hub genes of the two networks. GO analysis suggested that the network genes were involved in metabolic processes, biological regulation, and membrane and protein binding. KEGG analysis indicated that the significant pathways were the calcium signaling pathway, fatty acid biosynthesis, and pathways in cancer and insulin resistance. Some of the most significant hub genes were hsa-let-7b-3p, hsa-miR-378a-5p, hsa-miR-26a-5p, hsa-miR-382-5p, and hsa-miR-29b-2-5p and SECISBP2 L, NCOA1, HERC1, HIPK3, and MBNL1, respectively. These genes were predicted to be associated with the tumor prognostic reference for this patient population.
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MOTIVATION: Methylation and transcription factors (TFs) are part of the mechanisms regulating gene expression. However, the numerous mechanisms regulating the interactions between methylation and TFs remain unknown. We employ machine-learning techniques to discover the characteristics of TFs that bind to methylation sites. RESULTS: The classical machine-learning analysis process focuses on improving the performance of the analysis method. Conversely, we focus on the functional properties of the TF sequences. We obtain the principal properties of TFs, namely, the basic polar and hydrophobic Ile amino acids affecting the interaction between TFs and methylated DNA. The recall of the positive instances is 0.878 when their basic polar value is >0.1743. Both basic polar and hydrophobic Ile amino acids distinguish 74% of TFs bound to methylation sites. Therefore, we infer that basic polar amino acids affect the interactions of TFs with methylation sites. Based on our results, the role of the hydrophobic Ile residue is consistent with that described in previous studies, and the basic polar amino acids may also be a key factor modulating the interactions between TFs and methylation. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Fatores de Transcrição , Sequência de Bases , Sítios de Ligação , Metilação , Ligação Proteica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
BACKGROUND: A novel coronavirus (CoV), severe acute respiratory syndrome (SARS)-CoV-2, has infected >75â 000 individuals and spread to >20 countries. It is still unclear how fast the virus evolved and how it interacts with other microorganisms in the lung. METHODS: We have conducted metatranscriptome sequencing for bronchoalveolar lavage fluid samples from 8 patients with SARS-CoV-2, and also analyzed data from 25 patients with community-acquired pneumonia (CAP), and 20 healthy controls for comparison. RESULTS: The median number of intrahost variants was 1-4 in SARS-CoV-2-infected patients, ranged from 0 to 51 in different samples. The distribution of variants on genes was similar to those observed in the population data. However, very few intrahost variants were observed in the population as polymorphisms, implying either a bottleneck or purifying selection involved in the transmission of the virus, or a consequence of the limited diversity represented in the current polymorphism data. Although current evidence did not support the transmission of intrahost variants in a possible person-to-person spread, the risk should not be overlooked. Microbiotas in SARS-CoV-2-infected patients were similar to those in CAP, either dominated by the pathogens or with elevated levels of oral and upper respiratory commensal bacteria. CONCLUSION: SARS-CoV-2 evolves in vivo after infection, which may affect its virulence, infectivity, and transmissibility. Although how the intrahost variant spreads in the population is still elusive, it is necessary to strengthen the surveillance of the viral evolution in the population and associated clinical changes.
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Infecções por Coronavirus/epidemiologia , Coronavirus , Pandemias , Pneumonia Viral/epidemiologia , Síndrome Respiratória Aguda Grave , Betacoronavirus , COVID-19 , Variação Genética , Genômica , Humanos , SARS-CoV-2RESUMO
Brown planthopper (BPH) is one of the most destructive insects affecting rice (Oryza sativa L.) production. Phenylalanine ammonia-lyase (PAL) is a key enzyme involved in plant defense against pathogens, but the role of PAL in insect resistance is still poorly understood. Here we show that expression of the majority of PALs in rice is significantly induced by BPH feeding. Knockdown of OsPALs significantly reduces BPH resistance, whereas overexpression of OsPAL8 in a susceptible rice cultivar significantly enhances its BPH resistance. We found that OsPALs mediate resistance to BPH by regulating the biosynthesis and accumulation of salicylic acid and lignin. Furthermore, we show that expression of OsPAL6 and OsPAL8 in response to BPH attack is directly up-regulated by OsMYB30, an R2R3 MYB transcription factor. Taken together, our results demonstrate that the phenylpropanoid pathway plays an important role in BPH resistance response, and provide valuable targets for genetic improvement of BPH resistance in rice.
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Hemípteros/efeitos dos fármacos , Oryza/enzimologia , Oryza/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Fenilalanina Amônia-Liase/farmacologia , Doenças das Plantas/imunologia , Fatores de Transcrição/metabolismo , Animais , DNA de Plantas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Técnicas de Silenciamento de Genes , Genes de Plantas , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/fisiologia , Lignina/metabolismo , Oryza/genética , Oryza/imunologia , Fenilalanina Amônia-Liase/genética , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Ácido Salicílico/metabolismoRESUMO
Rice and maize are the principal food crop species worldwide. The mechanism of gene regulation for the yield of rice and maize is still the research focus at present. Seed size, weight and shape are important traits of crop yield in rice and maize. Most members of three gene families, APETALA2/ethylene response factor, auxin response factors and MADS, were identified to be involved in yield traits in rice and maize. Analysis of molecular regulation mechanisms related to yield traits provides theoretical support for the improvement of crop yield. Genetic regulatory network analysis can provide new insights into gene families with the improvement of sequencing technology. Here, we analyzed the evolutionary relationships and the genetic regulatory network for the gene family members to predicted genes that may be involved in yield-related traits in rice and maize. The results may provide some theoretical and application guidelines for future investigations of molecular biology, which may be helpful for developing new rice and maize varieties with high yield traits.
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The lysin motif (LysM) family comprise a number of defense proteins that play important roles in plant immunity. The LysM family includes LysM-containing receptor-like proteins (LYP) and LysM-containing receptor-like kinase (LYK). LysM generally recognizes the chitin and peptidoglycan derived from bacteria and fungi. Approximately 4000 proteins with the lysin motif (Pfam PF01476) are found in prokaryotes and eukaryotes. Our study identified 57 LysM genes and 60 LysM proteins in wheat and renamed these genes and proteins based on chromosome distribution. According to the phylogenetic and gene structure of intron-exon distribution analysis, the 60 LysM proteins were classified into seven groups. Gene duplication events had occurred among the LysM family members during the evolution process, resulting in an increase in the LysM gene family. Synteny analysis suggested the characteristics of evolution of the LysM family in wheat and other species. Systematic analysis of these species provided a foundation of LysM genes in crop defense. A comprehensive analysis of the expression and cis-elements of LysM gene family members suggested that they play an essential role in defending against plant pathogens. The present study provides an overview of the LysM family in the wheat genome as well as information on systematic, phylogenetic, gene duplication, and intron-exon distribution analyses that will be helpful for future functional analysis of this important protein family, especially in Gramineae species.
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Resistência à Doença/genética , Família Multigênica/genética , Proteínas de Plantas/genética , Triticum/genética , Motivos de Aminoácidos/genética , Resistência à Doença/imunologia , Evolução Molecular , Duplicação Gênica/imunologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas/imunologia , Genoma de Planta , Filogenia , Melhoramento Vegetal/métodos , Proteínas Serina-Treonina Quinases/genética , Receptores de Superfície Celular/genética , Sintenia/imunologia , Triticum/crescimento & desenvolvimento , Triticum/imunologiaRESUMO
In response to the current coronavirus disease 2019 (COVID-19) pandemic, it is crucial to understand the origin, transmission, and evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which relies on close surveillance of genomic diversity in clinical samples. Although the mutation at the population level had been extensively investigated, how the mutations evolve at the individual level is largely unknown. Eighteen time-series fecal samples were collected from nine patients with COVID-19 during the convalescent phase. The nucleic acids of SARS-CoV-2 were enriched by the hybrid capture method. First, we demonstrated the outstanding performance of the hybrid capture method in detecting intra-host variants. We identified 229 intra-host variants at 182 sites in 18 fecal samples. Among them, nineteen variants presented frequency changes > 0.3 within 1-5 days, reflecting highly dynamic intra-host viral populations. Moreover, the evolution of the viral genome demonstrated that the virus was probably viable in the gastrointestinal tract during the convalescent period. Meanwhile, we also found that the same mutation showed a distinct pattern of frequency changes in different individuals, indicating a strong random drift. In summary, dramatic changes of the SARS-CoV-2 genome were detected in fecal samples during the convalescent period; whether the viral load in feces is sufficient to establish an infection warranted further investigation.
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COVID-19/prevenção & controle , Fezes/virologia , Genoma Viral/genética , SARS-CoV-2/genética , COVID-19/epidemiologia , COVID-19/virologia , Convalescença , Perfilação da Expressão Gênica/métodos , Genômica/métodos , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mutação , Pandemias , Polimorfismo de Nucleotídeo Único , SARS-CoV-2/fisiologia , Fatores de TempoRESUMO
The completion of the rice genome sequence paved the way for rice functional genomics research. Additionally, the functional characterization of transcription factors is currently a popular and crucial objective among researchers. Transcription factors are one of the groups of proteins that bind to either enhancer or promoter regions of genes to regulate expression. On the basis of several typical examples of transcription factor analyses, we herein summarize selected research strategies and methods and introduce their advantages and disadvantages. This review may provide some theoretical and technical guidelines for future investigations of transcription factors, which may be helpful to develop new rice varieties with ideal traits.