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Peripheral sensory neurons widely innervate various tissues to continuously monitor and respond to environmental stimuli. Whether peripheral sensory neurons innervate the spleen and modulate splenic immune response remains poorly defined. Here, we demonstrate that nociceptive sensory nerve fibers extensively innervate the spleen along blood vessels and reach B cell zones. The spleen-innervating nociceptors predominantly originate from left T8-T13 dorsal root ganglia (DRGs), promoting the splenic germinal center (GC) response and humoral immunity. Nociceptors can be activated by antigen-induced accumulation of splenic prostaglandin E2 (PGE2) and then release calcitonin gene-related peptide (CGRP), which further promotes the splenic GC response at the early stage. Mechanistically, CGRP directly acts on B cells through its receptor CALCRL-RAMP1 via the cyclic AMP (cAMP) signaling pathway. Activating nociceptors by ingesting capsaicin enhances the splenic GC response and anti-influenza immunity. Collectively, our study establishes a specific DRG-spleen sensory neural connection that promotes humoral immunity, suggesting a promising approach for improving host defense by targeting the nociceptive nervous system.
Assuntos
Peptídeo Relacionado com Gene de Calcitonina , Centro Germinativo , Imunidade Humoral , Baço , Animais , Masculino , Camundongos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Capsaicina/farmacologia , AMP Cíclico/metabolismo , Dinoprostona/metabolismo , Gânglios Espinais/metabolismo , Centro Germinativo/imunologia , Camundongos Endogâmicos C57BL , Nociceptores/metabolismo , Proteína 1 Modificadora da Atividade de Receptores/metabolismo , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Transdução de Sinais , Baço/inervação , Baço/imunologia , FemininoRESUMO
Oakleaf butterflies in the genus Kallima have a polymorphic wing phenotype, enabling these insects to masquerade as dead leaves. This iconic example of protective resemblance provides an interesting evolutionary paradigm that can be employed to study biodiversity. We integrated multi-omic data analyses and functional validation to infer the evolutionary history of Kallima species and investigate the genetic basis of their variable leaf wing patterns. We find that Kallima butterflies diversified in the eastern Himalayas and dispersed to East and Southeast Asia. Moreover, we find that leaf wing polymorphism is controlled by the wing patterning gene cortex, which has been maintained in Kallima by long-term balancing selection. Our results provide macroevolutionary and microevolutionary insights into a model species originating from a mountain ecosystem.
Assuntos
Borboletas , Animais , Biodiversidade , Evolução Biológica , Borboletas/genética , Ecossistema , Fenótipo , Asas de AnimaisRESUMO
Alpha-synuclein (αS) is a conformationally plastic protein that reversibly binds to cellular membranes. It aggregates and is genetically linked to Parkinson's disease (PD). Here, we show that αS directly modulates processing bodies (P-bodies), membraneless organelles that function in mRNA turnover and storage. The N terminus of αS, but not other synucleins, dictates mutually exclusive binding either to cellular membranes or to P-bodies in the cytosol. αS associates with multiple decapping proteins in close proximity on the Edc4 scaffold. As αS pathologically accumulates, aberrant interaction with Edc4 occurs at the expense of physiologic decapping-module interactions. mRNA decay kinetics within PD-relevant pathways are correspondingly disrupted in PD patient neurons and brain. Genetic modulation of P-body components alters αS toxicity, and human genetic analysis lends support to the disease-relevance of these interactions. Beyond revealing an unexpected aspect of αS function and pathology, our data highlight the versatility of conformationally plastic proteins with high intrinsic disorder.
Assuntos
Doença de Parkinson , alfa-Sinucleína , Humanos , Doença de Parkinson/metabolismo , Corpos de Processamento , Estabilidade de RNA , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismoRESUMO
Rich fossil evidence suggests that many traits and functions related to terrestrial evolution were present long before the ancestor of lobe- and ray-finned fishes. Here, we present genome sequences of the bichir, paddlefish, bowfin, and alligator gar, covering all major early divergent lineages of ray-finned fishes. Our analyses show that these species exhibit many mosaic genomic features of lobe- and ray-finned fishes. In particular, many regulatory elements for limb development are present in these fishes, supporting the hypothesis that the relevant ancestral regulation networks emerged before the origin of tetrapods. Transcriptome analyses confirm the homology between the lung and swim bladder and reveal the presence of functional lung-related genes in early ray-finned fishes. Furthermore, we functionally validate the essential role of a jawed vertebrate highly conserved element for cardiovascular development. Our results imply the ancestors of jawed vertebrates already had the potential gene networks for cardio-respiratory systems supporting air breathing.
Assuntos
Evolução Biológica , Peixes/genética , Nadadeiras de Animais/fisiologia , Animais , Fenômenos Fisiológicos Cardiovasculares , Sistema Cardiovascular/anatomia & histologia , Extremidades/fisiologia , Peixes/classificação , Genoma , Pulmão/anatomia & histologia , Pulmão/fisiologia , Filogenia , Receptores Odorantes/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Vertebrados/classificação , Vertebrados/genéticaRESUMO
Lungfishes are the closest extant relatives of tetrapods and preserve ancestral traits linked with the water-to-land transition. However, their huge genome sizes have hindered understanding of this key transition in evolution. Here, we report a 40-Gb chromosome-level assembly of the African lungfish (Protopterus annectens) genome, which is the largest genome assembly ever reported and has a contig and chromosome N50 of 1.60 Mb and 2.81 Gb, respectively. The large size of the lungfish genome is due mainly to retrotransposons. Genes with ultra-long length show similar expression levels to other genes, indicating that lungfishes have evolved high transcription efficacy to keep gene expression balanced. Together with transcriptome and experimental data, we identified potential genes and regulatory elements related to such terrestrial adaptation traits as pulmonary surfactant, anxiolytic ability, pentadactyl limbs, and pharyngeal remodeling. Our results provide insights and key resources for understanding the evolutionary pathway leading from fishes to humans.
Assuntos
Adaptação Biológica , Evolução Biológica , Peixes/genética , Sequenciamento Completo do Genoma , Nadadeiras de Animais/anatomia & histologia , Nadadeiras de Animais/fisiologia , Animais , Extremidades/anatomia & histologia , Extremidades/fisiologia , Peixes/anatomia & histologia , Peixes/classificação , Peixes/fisiologia , Filogenia , Fenômenos Fisiológicos Respiratórios , Sistema Respiratório/anatomia & histologia , Vertebrados/genéticaRESUMO
CTCF is crucial for chromatin structure and transcription regulation in early embryonic development. However, the kinetics of CTCF chromatin occupation in preimplantation embryos have remained unclear. In this study, we used CUT&RUN technology to investigate CTCF occupancy in mouse preimplantation development. Our findings revealed that CTCF begins binding to the genome prior to zygotic genome activation (ZGA), with a preference for CTCF-anchored chromatin loops. Although the majority of CTCF occupancy is consistently maintained, we identified a specific set of binding sites enriched in the mouse-specific short interspersed element (SINE) family B2 that are restricted to the cleavage stages. Notably, we discovered that the neuroprotective protein ADNP counteracts the stable association of CTCF at SINE B2-derived CTCF-binding sites. Knockout of Adnp in the zygote led to impaired CTCF binding signal recovery, failed deposition of H3K9me3, and transcriptional derepression of SINE B2 during the morula-to-blastocyst transition, which further led to unfaithful cell differentiation in embryos around implantation. Our analysis highlights an ADNP-dependent restriction of CTCF binding during cell differentiation in preimplantation embryos. Furthermore, our findings shed light on the functional importance of transposable elements (TEs) in promoting genetic innovation and actively shaping the early embryo developmental process specific to mammals.
Assuntos
Cromatina , Desenvolvimento Embrionário , Animais , Camundongos , Sítios de Ligação , Blastocisto/metabolismo , Cromatina/metabolismo , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Mamíferos , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Zigoto/metabolismoRESUMO
Rice is sensitive to cold and can be grown only in certain climate zones. Human selection of japonica rice has extended its growth zone to regions with lower temperature, while the molecular basis of this adaptation remains unknown. Here, we identify the quantitative trait locus COLD1 that confers chilling tolerance in japonica rice. Overexpression of COLD1(jap) significantly enhances chilling tolerance, whereas rice lines with deficiency or downregulation of COLD1(jap) are sensitive to cold. COLD1 encodes a regulator of G-protein signaling that localizes on plasma membrane and endoplasmic reticulum (ER). It interacts with the G-protein α subunit to activate the Ca(2+) channel for sensing low temperature and to accelerate G-protein GTPase activity. We further identify that a SNP in COLD1, SNP2, originated from Chinese Oryza rufipogon, is responsible for the ability of COLD(jap/ind) to confer chilling tolerance, supporting the importance of COLD1 in plant adaptation.
Assuntos
Proteínas e Peptídeos de Choque Frio/metabolismo , Oryza/fisiologia , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Cruzamento , Proteínas e Peptídeos de Choque Frio/genética , Temperatura Baixa , Retículo Endoplasmático , Proteínas de Ligação ao GTP/química , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Mutação , Oryza/citologia , Oryza/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Alinhamento de SequênciaRESUMO
Metformin, the most prescribed antidiabetic medicine, has shown other benefits such as anti-ageing and anticancer effects1-4. For clinical doses of metformin, AMP-activated protein kinase (AMPK) has a major role in its mechanism of action4,5; however, the direct molecular target of metformin remains unknown. Here we show that clinically relevant concentrations of metformin inhibit the lysosomal proton pump v-ATPase, which is a central node for AMPK activation following glucose starvation6. We synthesize a photoactive metformin probe and identify PEN2, a subunit of γ-secretase7, as a binding partner of metformin with a dissociation constant at micromolar levels. Metformin-bound PEN2 forms a complex with ATP6AP1, a subunit of the v-ATPase8, which leads to the inhibition of v-ATPase and the activation of AMPK without effects on cellular AMP levels. Knockout of PEN2 or re-introduction of a PEN2 mutant that does not bind ATP6AP1 blunts AMPK activation. In vivo, liver-specific knockout of Pen2 abolishes metformin-mediated reduction of hepatic fat content, whereas intestine-specific knockout of Pen2 impairs its glucose-lowering effects. Furthermore, knockdown of pen-2 in Caenorhabditis elegans abrogates metformin-induced extension of lifespan. Together, these findings reveal that metformin binds PEN2 and initiates a signalling route that intersects, through ATP6AP1, the lysosomal glucose-sensing pathway for AMPK activation. This ensures that metformin exerts its therapeutic benefits in patients without substantial adverse effects.
Assuntos
Hipoglicemiantes , Metformina , ATPases Vacuolares Próton-Translocadoras , Proteínas Quinases Ativadas por AMP/metabolismo , Adenosina Trifosfatases/metabolismo , Secretases da Proteína Precursora do Amiloide , Animais , Caenorhabditis elegans/metabolismo , Diabetes Mellitus/tratamento farmacológico , Glucose/metabolismo , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Lisossomos/metabolismo , Proteínas de Membrana , Metformina/agonistas , Metformina/metabolismo , Metformina/farmacologia , ATPases Vacuolares Próton-Translocadoras/metabolismoRESUMO
MicroRNAs (miRNAs) are a class of nonprotein-coding short transcripts that provide a layer of post-transcriptional regulation essential to many plant biological processes. MiR858, which targets the transcripts of MYB transcription factors, can affect a range of secondary metabolic processes. Although miR858 and its 187-nt precursor have been well studied in Arabidopsis (Arabidopsis thaliana), a systematic investigation of miR858 precursors and their functions across plant species is lacking due to a problem in identifying the transcripts that generate this subclass. By re-evaluating the transcript of miR858 and relaxing the length cut-off for identifying hairpins, we found in kiwifruit (Actinidia chinensis) that miR858 has long-loop hairpins (1,100 to 2,100 nt), whose intervening sequences between miRNA generating complementary sites were longer than all previously reported miRNA hairpins. Importantly, these precursors of miR858 containing long-loop hairpins (termed MIR858L) are widespread in seed plants including Arabidopsis, varying between 350 and 5,500 nt. Moreover, we showed that MIR858L has a greater impact on proanthocyanidin and flavonol levels in both Arabidopsis and kiwifruit. We suggest that an active MIR858L-MYB regulatory module appeared in the transition of early land plants to large upright flowering plants, making a key contribution to plant secondary metabolism.
Assuntos
Actinidia , Arabidopsis , Regulação da Expressão Gênica de Plantas , MicroRNAs , RNA de Plantas , MicroRNAs/genética , MicroRNAs/metabolismo , Actinidia/genética , Actinidia/metabolismo , Arabidopsis/genética , RNA de Plantas/genética , RNA de Plantas/metabolismo , Sementes/genética , Sementes/metabolismo , Sequência de BasesRESUMO
The flower-infecting fungus Ustilaginoidea virens causes rice false smut, which is a severe emerging disease threatening rice (Oryza sativa) production worldwide. False smut not only reduces yield, but more importantly produces toxins on grains, posing a great threat to food safety. U. virens invades spikelets via the gap between the 2 bracts (lemma and palea) enclosing the floret and specifically infects the stamen and pistil. Molecular mechanisms for the U. virens-rice interaction are largely unknown. Here, we demonstrate that rice flowers predominantly employ chitin-triggered immunity against U. virens in the lemma and palea, rather than in the stamen and pistil. We identify a crucial U. virens virulence factor, named UvGH18.1, which carries glycoside hydrolase activity. Mechanistically, UvGH18.1 functions by binding to and hydrolyzing immune elicitor chitin and interacting with the chitin receptor CHITIN ELICITOR BINDING PROTEIN (OsCEBiP) and co-receptor CHITIN ELICITOR RECEPTOR KINASE1 (OsCERK1) to impair their chitin-induced dimerization, suppressing host immunity exerted at the lemma and palea for gaining access to the stamen and pistil. Conversely, pretreatment on spikelets with chitin induces a defense response in the lemma and palea, promoting resistance against U. virens. Collectively, our data uncover a mechanism for a U. virens virulence factor and the critical location of the host-pathogen interaction in flowers and provide a potential strategy to control rice false smut disease.
Assuntos
Quitina , Flores , Hypocreales , Oryza , Doenças das Plantas , Oryza/microbiologia , Oryza/metabolismo , Oryza/genética , Doenças das Plantas/microbiologia , Quitina/metabolismo , Flores/microbiologia , Hypocreales/patogenicidade , Hypocreales/genética , Hypocreales/metabolismo , Transdução de Sinais , Interações Hospedeiro-Patógeno , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Virulência , Fatores de Virulência/metabolismo , Fatores de Virulência/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genéticaRESUMO
Tumor heterogeneity presents a challenge for inferring clonal evolution and driver gene identification. Here, we describe a method for analyzing the cancer genome at a single-cell nucleotide level. To perform our analyses, we first devised and validated a high-throughput whole-genome single-cell sequencing method using two lymphoblastoid cell line single cells. We then carried out whole-exome single-cell sequencing of 90 cells from a JAK2-negative myeloproliferative neoplasm patient. The sequencing data from 58 cells passed our quality control criteria, and these data indicated that this neoplasm represented a monoclonal evolution. We further identified essential thrombocythemia (ET)-related candidate mutations such as SESN2 and NTRK1, which may be involved in neoplasm progression. This pilot study allowed the initial characterization of the disease-related genetic architecture at the single-cell nucleotide level. Further, we established a single-cell sequencing method that opens the way for detailed analyses of a variety of tumor types, including those with high genetic complex between patients.
Assuntos
Evolução Clonal , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Janus Quinase 2/genética , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Análise de Célula Única/métodos , Trombocitemia Essencial/genética , Exoma , Genoma Humano , Humanos , Masculino , Pessoa de Meia-Idade , MutaçãoRESUMO
Sulfur in nature consists of two abundant stable isotopes, with two more neutrons in the heavy one (34S) than in the light one (32S). The two isotopes show similar physicochemical properties and are usually considered an integral system for chemical research in various fields. In this work, a model study based on a Li-S battery was performed to reveal the variation between the electrochemical properties of the two S isotopes. Provided with the same octatomic ring structure, the cyclo-34S8 molecules form stronger S-S bonds than cyclo-32S8 and are more prone to react with Li. The soluble Li polysulfides generated by the Li-34S conversion reaction show a stronger cation-solvent interaction yet a weaker cation-anion interaction than the 32S-based counterparts, which facilitates quick solvation of polysulfides yet hinders their migration from the cathode to the anode. Consequently, the Li-34S cell shows improved cathode reaction kinetics at the solid-liquid interface and inhibited shuttle of polysulfides through the electrolyte so that it demonstrates better cycling performance than the Li-32S cell. Based on the varied shuttle kinetics of the isotopic-S-based polysulfides, an electrochemical separation method for 34S/32S isotope is proposed, which enables a notably higher separation factor than the conventional separation methods via chemical exchange or distillation and brings opportunities to low-cost manufacture, utilization, and research of heavy chalcogen isotopes.
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Immune-mediated necrotizing myopathy (IMNM) is an autoimmune disorder associated with the presence of autoantibodies, characterized by severe clinical presentation with rapidly progressive muscular weakness and elevated levels of creatine kinase, while traditional pharmacological approaches possess varying and often limited effects. Considering the pathogenic role of autoantibodies, chimeric antigen receptor (CAR)-T cells targeting B cell maturation antigen (BCMA) have emerged as a promising therapeutic strategy. We reported here a patient with anti-signal recognition particle IMNM refractory to multiple available therapies, who was treated with BCMA-targeting CAR-T cells, exhibited favorable safety profiles, sustained reduction in pathogenic autoantibodies, and persistent clinical improvements over 18 mo. Longitudinal single-cell RNA, B cell receptor, T cell receptor sequencing analysis presented the normalization of immune microenvironment after CAR-T cell infusion, including reconstitution of B cell lineages, replacement of T cell subclusters, and suppression of overactivated immune cells. Analysis on characteristics of CAR-T cells in IMNM demonstrated a more active expansion of CD8+ CAR-T cells, with a dynamic phenotype shifting pattern similar in CD4+ and CD8+ CAR-T cells. A comparison of CD8+ CAR-T cells in patients with IMNM and those with malignancies collected at different timepoints revealed a more NK-like phenotype with enhanced tendency of cell death and neuroinflammation and inhibited proliferating ability of CD8+ CAR-T cells in IMNM while neuroinflammation might be the distinct characteristics. Further studies are warranted to define the molecular features of CAR-T cells in autoimmunity and to seek higher efficiency and longer persistence of CAR-T cells in treating autoimmune disorders.
Assuntos
Doenças Autoimunes , Mieloma Múltiplo , Doenças Musculares , Receptores de Antígenos Quiméricos , Humanos , Mieloma Múltiplo/tratamento farmacológico , Antígeno de Maturação de Linfócitos B , Doenças Neuroinflamatórias , Imunoterapia Adotiva , Doenças Autoimunes/terapia , Autoanticorpos , Doenças Musculares/terapia , Análise de Célula Única , Terapia Baseada em Transplante de Células e Tecidos , Microambiente TumoralRESUMO
Small peptides modulate multiple processes in plant cells, but their regulation by post-translational modification remains unclear. ROT4 (ROTUNDIFOLIA4) belongs to a family of Arabidopsis non-secreted small peptides, but knowledge on its molecular function and how it is regulated is limited. Here, we find that ROT4 is S-acylated in plant cells. S-acylation is an important form of protein lipidation, yet so far it has not been reported to regulate small peptides in plants. We show that this modification is essential for the plasma membrane association of ROT4. Overexpression of S-acylated ROT4 results in a dramatic increase in immune gene expression. S-acylation of ROT4 enhances its interaction with BSK5 (BRASSINOSTEROID-SIGNALING KINASE 5) to block the association between BSK5 and PEPR1 (PEP RECEPTOR1), a receptor kinase for secreted plant elicitor peptides (PEPs), thereby activating immune signaling. Phenotype analysis indicates that S-acylation is necessary for ROT4 functions in pathogen resistance, PEP response, and the regulation of development. Collectively, our work reveals an important role for S-acylation in the cross-talk of non-secreted and secreted peptide signaling in plant immunity.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Plantas/metabolismo , Peptídeos/metabolismo , Acilação , Imunidade Vegetal , Proteínas Quinases/metabolismoRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMO
Emerging infectious diseases, such as severe acute respiratory syndrome (SARS) and Zika virus disease, present a major threat to public health1-3. Despite intense research efforts, how, when and where new diseases appear are still a source of considerable uncertainty. A severe respiratory disease was recently reported in Wuhan, Hubei province, China. As of 25 January 2020, at least 1,975 cases had been reported since the first patient was hospitalized on 12 December 2019. Epidemiological investigations have suggested that the outbreak was associated with a seafood market in Wuhan. Here we study a single patient who was a worker at the market and who was admitted to the Central Hospital of Wuhan on 26 December 2019 while experiencing a severe respiratory syndrome that included fever, dizziness and a cough. Metagenomic RNA sequencing4 of a sample of bronchoalveolar lavage fluid from the patient identified a new RNA virus strain from the family Coronaviridae, which is designated here 'WH-Human 1' coronavirus (and has also been referred to as '2019-nCoV'). Phylogenetic analysis of the complete viral genome (29,903 nucleotides) revealed that the virus was most closely related (89.1% nucleotide similarity) to a group of SARS-like coronaviruses (genus Betacoronavirus, subgenus Sarbecovirus) that had previously been found in bats in China5. This outbreak highlights the ongoing ability of viral spill-over from animals to cause severe disease in humans.
Assuntos
Betacoronavirus/classificação , Doenças Transmissíveis Emergentes/complicações , Doenças Transmissíveis Emergentes/virologia , Infecções por Coronavirus/complicações , Infecções por Coronavirus/virologia , Pneumonia Viral/complicações , Pneumonia Viral/virologia , Síndrome Respiratória Aguda Grave/etiologia , Síndrome Respiratória Aguda Grave/virologia , Adulto , Betacoronavirus/genética , COVID-19 , China , Doenças Transmissíveis Emergentes/diagnóstico por imagem , Doenças Transmissíveis Emergentes/patologia , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/patologia , Genoma Viral/genética , Humanos , Pulmão/diagnóstico por imagem , Masculino , Filogenia , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/patologia , RNA Viral/genética , Recombinação Genética/genética , SARS-CoV-2 , Síndrome Respiratória Aguda Grave/diagnóstico por imagem , Síndrome Respiratória Aguda Grave/patologia , Tomografia Computadorizada por Raios X , Sequenciamento Completo do GenomaRESUMO
The high-valent cobalt-oxo species (Co(IV)=O) is being increasingly investigated for water purification because of its high redox potential, long half-life, and antiinterference properties. However, generation of Co(IV)=O is inefficient and unsustainable. Here, a cobalt-single-atom catalyst with N/O dual coordination was synthesized by O-doping engineering. The O-doped catalyst (Co-OCN) greatly activated peroxymonosulfate (PMS) and achieved a pollutant degradation kinetic constant of 73.12 min-1 g-2, which was 4.9 times higher than that of Co-CN (catalyst without O-doping) and higher than those of most reported single-atom catalytic PMS systems. Co-OCN/PMS realized Co(IV)=O dominant oxidation of pollutants by increasing the steady-state concentration of Co(IV)=O (1.03 × 10-10 M) by 5.9 times compared with Co-CN/PMS. A competitive kinetics calculation showed that the oxidation contribution of Co(IV)=O to micropollutant degradation was 97.5% during the Co-OCN/PMS process. Density functional theory calculations showed that O-doping influenced the charge density (increased the Bader charge transfer from 0.68 to 0.85 e), optimized the electron distribution of the Co center (increased the d-band center from -1.14 to -1.06 eV), enhanced the PMS adsorption energy from -2.46 to -3.03 eV, and lowered the energy barrier for generation of the key reaction intermediate (*O*H2O) during Co(IV)=O formation from 1.12 to 0.98 eV. The Co-OCN catalyst was fabricated on carbon felt for a flow-through device, which achieved continuous and efficient removal of micropollutants (degradation efficiency of >85% after 36 h operation). This study provides a new protocol for PMS activation and pollutant elimination through single-atom catalyst heteroatom-doping and high-valent metal-oxo formation during water purification.
RESUMO
Most of kiwifruit cultivars (e.g. Actinidia chinensis cv. Donghong, "DH") were sensitive to waterlogging, thus, waterlogging resistant rootstocks (e.g. Actinidia valvata Dunn, "Dunn") were widely used for kiwifruit industry. Those different species provided ideal materials to understand the waterlogging responses in kiwifruit. Compared to the weaken growth and root activities in "DH", "Dunn" maintained the relative high root activities under the prolonged waterlogging. Based on comparative analysis, transcript levels of pyruvate decarboxylase (PDCs) and alcohol dehydrogenase (ADHs) showed significantly difference between these two species. Both PDCs and ADHs had been significantly increased by waterlogging in "DH", while they were only limitedly triggered by 2 days stress and subsided during the prolonged waterlogging in "Dunn". Thus, 19 differentially expressed transcript factors (DETFs) had been isolated using weighted gene co-expression network analysis combined with transcriptomics and transcript levels of PDCs and ADHs in waterlogged "DH". Among these DETFs, dual luciferase and electrophoretic mobility shift assays indicated AcMYB68 could bind to and trigger the activity of AcPDC2 promoter. The stable over-expression of AcMYB68 significantly up-regulated the transcript levels of PDCs but inhibited the plant growth, especially the roots. Moreover, the enzyme activities of PDC in 35S::AcMYB68 were significantly enhanced during the waterlogging response than that in wild type plants. Most interestingly, comparative analysis indicated that the expression patterns of AcMYB68 and the previously characterized AcERF74/75 (the direct regulator on ADHs) either showed no responses (AcMYB68 and AcERF74) or very limited response (AcERF75) in "Dunn". Taken together, the restricted responses of AcMYB68 and AcERF74/75 in "Dunn" endow its waterlogging tolerance.
Assuntos
Actinidia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Piruvato Descarboxilase , Actinidia/genética , Actinidia/fisiologia , Actinidia/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Piruvato Descarboxilase/genética , Piruvato Descarboxilase/metabolismo , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Água/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Estresse Fisiológico , Regiões Promotoras Genéticas/genéticaRESUMO
The coronavirus SARS-CoV-2, the agent of the deadly COVID-19 pandemic, is an enveloped virus propagating within the endocytic and secretory organelles of host mammalian cells. Enveloped viruses modify the ionic homeostasis of organelles to render their intra-luminal milieu permissive for viral entry, replication and egress. Here, we show that infection of Vero E6 cells with the delta variant of the SARS-CoV-2 alkalinizes the endoplasmic reticulum (ER)-Golgi intermediate compartment (ERGIC) as well as lysosomes, mimicking the effect of inhibitors of vacuolar proton ATPases. We further show the envelope protein of SARS-CoV-2 accumulates in the ERGIC when expressed in mammalian cells and selectively dissipates the ERGIC pH. This viroporin action is prevented by mutations of Val25 but not Asn15 within the channel pore of the envelope (E) protein. We conclude that the envelope protein acts as a proton channel in the ERGIC to mitigate the acidity of this intermediate compartment. The altered pH homeostasis of the ERGIC likely contributes to the virus fitness and pathogenicity, making the E channel an attractive drug target for the treatment of COVID-19.
Assuntos
COVID-19 , Proteínas do Envelope Viral , Animais , Humanos , Proteínas do Envelope Viral/metabolismo , Proteínas Viroporinas/metabolismo , COVID-19/metabolismo , Prótons , Pandemias , SARS-CoV-2/metabolismo , Complexo de Golgi/metabolismo , Lisossomos/metabolismo , Mamíferos/metabolismoRESUMO
Key transcription factors (TFs) play critical roles in zygotic genome activation (ZGA) during early embryogenesis, whereas genome-wide occupancies of only a few factors have been profiled during ZGA due to the limitation of cell numbers or the lack of high-quality antibodies. Here, we present FitCUT&RUN, a modified CUT&RUN method, in which an Fc fragment of immunoglobulin G is used for tagging, to profile TF occupancy in an antibody-free manner and demonstrate its reliability and robustness using as few as 5000 K562 cells. We applied FitCUT&RUN to zebrafish undergoing embryogenesis to generate reliable occupancy profiles of three known activators of zebrafish ZGA: Nanog, Pou5f3, and Sox19b. By profiling the time-series occupancy of Nanog during zebrafish ZGA, we observed a clear trend toward a gradual increase in Nanog occupancy and found that Nanog occupancy prior to the major phase of ZGA is important for the activation of some early transcribed genes.