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1.
Cell ; 179(4): 864-879.e19, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31675497

RESUMO

Physical or mental stress leads to neuroplasticity in the brain and increases the risk of depression and anxiety. Stress exposure causes the dysfunction of peripheral T lymphocytes. However, the pathological role and underlying regulatory mechanism of peripheral T lymphocytes in mood disorders have not been well established. Here, we show that the lack of CD4+ T cells protects mice from stress-induced anxiety-like behavior. Physical stress-induced leukotriene B4 triggers severe mitochondrial fission in CD4+ T cells, which further leads to a variety of behavioral abnormalities including anxiety, depression, and social disorders. Metabolomic profiles and single-cell transcriptome reveal that CD4+ T cell-derived xanthine acts on oligodendrocytes in the left amygdala via adenosine receptor A1. Mitochondrial fission promotes the de novo synthesis of purine via interferon regulatory factor 1 accumulation in CD4+ T cells. Our study implicates a critical link between a purine metabolic disorder in CD4+ T cells and stress-driven anxiety-like behavior.


Assuntos
Ansiedade/metabolismo , Comportamento Animal/fisiologia , Encefalopatias Metabólicas/metabolismo , Estresse Psicológico/metabolismo , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/patologia , Animais , Ansiedade/genética , Ansiedade/imunologia , Ansiedade/fisiopatologia , Encefalopatias Metabólicas/genética , Encefalopatias Metabólicas/fisiopatologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Dinâmica Mitocondrial/genética , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Análise de Célula Única , Estresse Psicológico/genética , Estresse Psicológico/fisiopatologia , Transcriptoma/genética , Xantina/metabolismo
2.
Mol Cell ; 82(6): 1225-1238.e6, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35196517

RESUMO

The long-range interactions of cis-regulatory elements (cREs) play a central role in gene regulation. cREs can be characterized as accessible chromatin sequences. However, it remains technically challenging to comprehensively identify their spatial interactions. Here, we report a new method HiCAR (Hi-C on accessible regulatory DNA), which utilizes Tn5 transposase and chromatin proximity ligation, for the analysis of open-chromatin-anchored interactions with low-input cells. By applying HiCAR in human embryonic stem cells and lymphoblastoid cells, we demonstrate that HiCAR identifies high-resolution chromatin contacts with an efficiency comparable with that of in situ Hi-C over all distance ranges. Interestingly, we found that the "poised" gene promoters exhibit silencer-like function to repress the expression of distal genes via promoter-promoter interactions. Lastly, we applied HiCAR to 30,000 primary human muscle stem cells and demonstrated that HiCAR is capable of analyzing chromatin accessibility and looping using low-input primary cells and clinical samples.


Assuntos
Cromatina , Sequências Reguladoras de Ácido Nucleico , Cromatina/genética , DNA , Regulação da Expressão Gênica , Humanos , Regiões Promotoras Genéticas
3.
Nature ; 607(7919): 480-485, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35859196

RESUMO

Pyroelectricity describes the generation of electricity by temporal temperature change in polar materials1-3. When free-standing pyroelectric materials approach the 2D crystalline limit, how pyroelectricity behaves remained largely unknown. Here, using three model pyroelectric materials whose bonding characters along the out-of-plane direction vary from van der Waals (In2Se3), quasi-van der Waals (CsBiNb2O7) to ionic/covalent (ZnO), we experimentally show the dimensionality effect on pyroelectricity and the relation between lattice dynamics and pyroelectricity. We find that, for all three materials, when the thickness of free-standing sheets becomes small, their pyroelectric coefficients increase rapidly. We show that the material with chemical bonds along the out-of-plane direction exhibits the greatest dimensionality effect. Experimental observations evidence the possible influence of changed phonon dynamics in crystals with reduced thickness on their pyroelectricity. Our findings should stimulate fundamental study on pyroelectricity in ultra-thin materials and inspire technological development for potential pyroelectric applications in thermal imaging and energy harvesting.

4.
Nature ; 612(7940): 503-511, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36477535

RESUMO

The neocortex consists of a vast number of diverse neurons that form distinct layers and intricate circuits at the single-cell resolution to support complex brain functions1. Diverse cell-surface molecules are thought to be key for defining neuronal identity, and they mediate interneuronal interactions for structural and functional organization2-6. However, the precise mechanisms that control the fine neuronal organization of the neocortex remain largely unclear. Here, by integrating in-depth single-cell RNA-sequencing analysis, progenitor lineage labelling and mosaic functional analysis, we report that the diverse yet patterned expression of clustered protocadherins (cPCDHs)-the largest subgroup of the cadherin superfamily of cell-adhesion molecules7-regulates the precise spatial arrangement and synaptic connectivity of excitatory neurons in the mouse neocortex. The expression of cPcdh genes in individual neocortical excitatory neurons is diverse yet exhibits distinct composition patterns linked to their developmental origin and spatial positioning. A reduction in functional cPCDH expression causes a lateral clustering of clonally related excitatory neurons originating from the same neural progenitor and a significant increase in synaptic connectivity. By contrast, overexpression of a single cPCDH isoform leads to a lateral dispersion of clonally related excitatory neurons and a considerable decrease in synaptic connectivity. These results suggest that patterned cPCDH expression biases fine spatial and functional organization of individual neocortical excitatory neurons in the mammalian brain.


Assuntos
Regulação da Expressão Gênica , Neocórtex , Protocaderinas , Animais , Camundongos , Interneurônios/metabolismo , Neocórtex/anatomia & histologia , Neocórtex/citologia , Neocórtex/metabolismo , Neurônios/metabolismo , Protocaderinas/genética , Protocaderinas/metabolismo , Sinapses/metabolismo , Transmissão Sináptica
5.
Proc Natl Acad Sci U S A ; 121(19): e2401386121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38696471

RESUMO

In the meiotic prophase, programmed DNA double-strand breaks are repaired by meiotic recombination. Recombination-defective meiocytes are eliminated to preserve genome integrity in gametes. BRCA1 is a critical protein in somatic homologous recombination, but studies have suggested that BRCA1 is dispensable for meiotic recombination. Here we show that BRCA1 is essential for meiotic recombination. Interestingly, BRCA1 also has a function in eliminating recombination-defective oocytes. Brca1 knockout (KO) rescues the survival of Dmc1 KO oocytes far more efficiently than removing CHK2, a vital component of the DNA damage checkpoint in oocytes. Mechanistically, BRCA1 activates chromosome asynapsis checkpoint by promoting ATR activity at unsynapsed chromosome axes in Dmc1 KO oocytes. Moreover, Brca1 KO also rescues the survival of asynaptic Spo11 KO oocytes. Collectively, our study not only unveils an unappreciated role of chromosome asynapsis in eliminating recombination-defective oocytes but also reveals the dual functions of BRCA1 in safeguarding oocyte genome integrity.


Assuntos
Proteína BRCA1 , Proteínas de Ciclo Celular , Camundongos Knockout , Oócitos , Oócitos/metabolismo , Animais , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Feminino , Camundongos , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Meiose/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/deficiência , Quebras de DNA de Cadeia Dupla , Pareamento Cromossômico/genética , Endodesoxirribonucleases/metabolismo , Endodesoxirribonucleases/genética , Quinase do Ponto de Checagem 2/genética , Quinase do Ponto de Checagem 2/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Proteínas de Ligação a Fosfato/genética , Recombinação Genética , Recombinação Homóloga , Instabilidade Genômica
6.
Nature ; 580(7801): 106-112, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32238932

RESUMO

Radial glial progenitor cells (RGPs) are the major neural progenitor cells that generate neurons and glia in the developing mammalian cerebral cortex1-4. In RGPs, the centrosome is positioned away from the nucleus at the apical surface of the ventricular zone of the cerebral cortex5-8. However, the molecular basis and precise function of this distinctive subcellular organization of the centrosome are largely unknown. Here we show in mice that anchoring of the centrosome to the apical membrane controls the mechanical properties of cortical RGPs, and consequently their mitotic behaviour and the size and formation of the cortex. The mother centriole in RGPs develops distal appendages that anchor it to the apical membrane. Selective removal of centrosomal protein 83 (CEP83) eliminates these distal appendages and disrupts the anchorage of the centrosome to the apical membrane, resulting in the disorganization of microtubules and stretching and stiffening of the apical membrane. The elimination of CEP83 also activates the mechanically sensitive yes-associated protein (YAP) and promotes the excessive proliferation of RGPs, together with a subsequent overproduction of intermediate progenitor cells, which leads to the formation of an enlarged cortex with abnormal folding. Simultaneous elimination of YAP suppresses the cortical enlargement and folding that is induced by the removal of CEP83. Together, these results indicate a previously unknown role of the centrosome in regulating the mechanical features of neural progenitor cells and the size and configuration of the mammalian cerebral cortex.


Assuntos
Centrossomo/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/embriologia , Células Ependimogliais/citologia , Células-Tronco Neurais/citologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Ciclo Celular/metabolismo , Membrana Celular/metabolismo , Membrana Celular/patologia , Proliferação de Células , Centríolos/metabolismo , Córtex Cerebral/patologia , Feminino , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/deficiência , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Microtúbulos/patologia , Neurogênese , Proteínas de Sinalização YAP
7.
Nucleic Acids Res ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39351893

RESUMO

Exploring the causal relationships of diseases with genes, proteins, CpG sites, metabolites and other diseases is fundamental to the life sciences. However, large-scale research using Mendelian randomization (MR) analysis is currently lacking. To address this, we introduce DMRdb (http://www.inbirg.com/DMRdb/), a disease-centric Mendelian randomization database, designed to systematically assess causal relationships of diseases with genes, proteins, CpG sites, metabolites and other diseases. The database consists of three main components: (i) 6640 high-quality disease genome-wide association studies (GWASs) from public sources that were subjected to rigorous quality filtering and standardization; (ii) over 497 billion results from MR analyses involving 6640 disease GWAS datasets, 16 238 expression quantitative trait loci (eQTLs) data, 2564 protein quantitative trait loci (pQTLs) data, 12 000 methylation quantitative trait locus (meQTLs) data and 825 metabolites data and (iii) over 380 000 causal relationship pairs from 1223 literature sources relevant to MR analyses. A user-friendly online database was developed to allow users to query, search, and download all the results. In summary, we anticipate that DMRdb will be a valuable resource for advancing our understanding of disease mechanisms and identifying new biomarkers and therapeutic targets.

8.
Nucleic Acids Res ; 52(11): 6201-6219, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38597673

RESUMO

Genes encoding the KDM5 family of transcriptional regulators are disrupted in individuals with intellectual disability (ID). To understand the link between KDM5 and ID, we characterized five Drosophila strains harboring missense alleles analogous to those observed in patients. These alleles disrupted neuroanatomical development, cognition and other behaviors, and displayed a transcriptional signature characterized by the downregulation of many ribosomal protein genes. A similar transcriptional profile was observed in KDM5C knockout iPSC-induced human glutamatergic neurons, suggesting an evolutionarily conserved role for KDM5 proteins in regulating this class of gene. In Drosophila, reducing KDM5 changed neuronal ribosome composition, lowered the translation efficiency of mRNAs required for mitochondrial function, and altered mitochondrial metabolism. These data highlight the cellular consequences of altered KDM5-regulated transcriptional programs that could contribute to cognitive and behavioral phenotypes. Moreover, they suggest that KDM5 may be part of a broader network of proteins that influence cognition by regulating protein synthesis.


Assuntos
Proteínas de Drosophila , Neurônios , Proteínas Ribossômicas , Animais , Humanos , Drosophila/genética , Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Histona Desmetilases/metabolismo , Histona Desmetilases/genética , Deficiência Intelectual/genética , Deficiência Intelectual/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/genética , Neurônios/metabolismo , Biossíntese de Proteínas , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Ribossomos/genética , Ativação Transcricional
9.
Plant Physiol ; 195(2): 1642-1659, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38431524

RESUMO

Maize (Zea mays) smut is a common biotrophic fungal disease caused by Ustilago maydis and leads to low maize yield. Maize resistance to U. maydis is a quantitative trait. However, the molecular mechanism underlying the resistance of maize to U. maydis is poorly understood. Here, we reported that a maize mutant caused by a single gene mutation exhibited defects in both fungal resistance and plant development. maize mutant highly susceptible to U. maydis (mmsu) with a dwarf phenotype forms tumors in the ear. A map-based cloning and allelism test demonstrated that 1 gene encoding a putative arogenate dehydratase/prephenate dehydratase (ADT/PDT) is responsible for the phenotypes of the mmsu and was designated as ZmADT2. Combined transcriptomic and metabolomic analyses revealed that mmsu had substantial differences in multiple metabolic pathways in response to U. maydis infection compared with the wild type. Disruption of ZmADT2 caused damage to the chloroplast ultrastructure and function, metabolic flux redirection, and reduced the amounts of salicylic acid (SA) and lignin, leading to susceptibility to U. maydis and dwarf phenotype. These results suggested that ZmADT2 is required for maintaining metabolic flux, as well as resistance to U. maydis and plant development in maize. Meanwhile, our findings provided insights into the maize response mechanism to U. maydis infection.


Assuntos
Resistência à Doença , Hidroliases , Doenças das Plantas , Zea mays , Basidiomycota/fisiologia , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Hidroliases/genética , Hidroliases/metabolismo , Mutação/genética , Fenótipo , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Salicílico/metabolismo , Ustilago/genética , Zea mays/microbiologia , Zea mays/genética , Zea mays/crescimento & desenvolvimento
10.
Plant Physiol ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39222356

RESUMO

Maize (Zea mays L.) kernel development is a complex and dynamic process involving cell division and differentiation, into a variety of cell types. Epigenetic modifications, including DNA methylation, play a pivotal role in regulating this process. N6-methyladenosine modification is a universal and dynamic post-transcriptional epigenetic modification that is involved in the regulation of plant development. However, the role of N6-methyladenosine in maize kernel development remains unknown. In this study, we have constructed transcriptome-wide profiles for maize kernels at various stages of early development. Utilizing a combination of MeRIP-seq and RNA-seq analysis, we identified a total of 11,170, 10,973, 11,094, 11,990, 12,203 and 10,893 N6-methyladenosine peaks in maize kernels at 0, 2, 4, 6, 8, and 12 days after pollination, respectively. These N6-methyladenosine modifications were primarily deposited at the 3'-UTRs and were associated with the conserved motif-UGUACA. Additionally, we found that conserved N6-methyladenosine modification are involved in the regulation of genes that are ubiquitously expressed during kernel development. Further analysis revealed that N6-methyladenosine peak intensity was negatively correlated with the mRNA abundance of these ubiquitously expressed genes. Meanwhile, we employed phylogenetic analysis to predict potential regulatory proteins involved in maize kernels development and identified several that participate in the regulation of N6-methyladenosine modifications. Collectively, our results suggest the existence of a novel post-transcriptional epigenetic modification mechanism involved in the regulation of maize kernels development, thereby providing a novel perspective for maize molecular breeding.

11.
Mol Psychiatry ; 29(3): 767-781, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38238548

RESUMO

BACKGROUND: Although network analysis studies of psychiatric syndromes have increased in recent years, most have emphasized centrality symptoms and robust edges. Broadening the focus to include bridge symptoms within a systematic review could help to elucidate symptoms having the strongest links in network models of psychiatric syndromes. We conducted this systematic review and statistical evaluation of network analyses on depressive and anxiety symptoms to identify the most central symptoms and bridge symptoms, as well as the most robust edge indices of networks. METHODS: A systematic literature search was performed in PubMed, PsycINFO, Web of Science, and EMBASE databases from their inception to May 25, 2022. To determine the most influential symptoms and connections, we analyzed centrality and bridge centrality rankings and aggregated the most robust symptom connections into a summary network. After determining the most central symptoms and bridge symptoms across network models, heterogeneity across studies was examined using linear logistic regression. RESULTS: Thirty-three studies with 78,721 participants were included in this systematic review. Seventeen studies with 23 cross-sectional networks based on the Patient Health Questionnaire (PHQ) and Generalized Anxiety Disorder (GAD-7) assessments of clinical and community samples were examined using centrality scores. Twelve cross-sectional networks based on the PHQ and GAD-7 assessments were examined using bridge centrality scores. We found substantial variability between study samples and network features. 'Sad mood', 'Uncontrollable worry', and 'Worrying too much' were the most central symptoms, while 'Sad mood', 'Restlessness', and 'Motor disturbance' were the most frequent bridge centrality symptoms. In addition, the connection between 'Sleep' and 'Fatigue' was the most frequent edge for the depressive and anxiety symptoms network model. CONCLUSION: Central symptoms, bridge symptoms and robust edges identified in this systematic review can be viewed as potential intervention targets. We also identified gaps in the literature and future directions for network analysis of comorbid depression and anxiety.


Assuntos
Ansiedade , Depressão , Feminino , Humanos , Masculino , Ansiedade/complicações , Ansiedade/terapia , Transtornos de Ansiedade , Estudos Transversais , Depressão/complicações , Depressão/terapia
12.
J Am Soc Nephrol ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39446490

RESUMO

BACKGROUND: Damages to subcellular organelles, such as mitochondria and endoplasmic reticulum, are well-recognized in tubular cell injury and death in acute kidney injury (AKI). However, the changes and involvement of Golgi apparatus are much less known. Here, we report the regulation and role of N-acetylgalactosaminyltransferase-3 (GALNT3), a key enzyme for protein glycosylation in Golgi apparatus, in AKI. METHODS: AKI was induced in mice by renal ischemia-reperfusion or cisplatin. In vitro, rat kidney proximal tubular cells were subjected to hypoxia/reoxygenation (H/R) injury. To determine the role of GALNT3, its specific inhibitor T3inh-1 was tested in mice, and the effects of GALNT3 overexpression as well as knockdown were examined in the rat renal proximal tubular cells. EGFR activation was induced by recombinant EGF or by overexpressing EGFR. RESULTS: GALNT3 was significantly decreased in both in vivo and in vitro models of AKI induced by renal ischemia-reperfusion and cisplatin. T3Inh-1, a specific GALNT3 inhibitor, exacerbated ischemic AKI and suppressed tubular cell proliferation in mice. Moreover, knockdown of GALNT3 increased apoptosis during H/R treatment in rat renal proximal tubular cells, while overexpression of GALNT3 attenuated H/R-induced apoptosis, further supporting a protective role of GALNT3. Mechanistically, GALNT3 contributed to O-glycosylation of epidermal growth factor receptor (EGFR) and associated EGFR signalling. Activation or overexpression of EGFR suppressed the pro-apoptotic effect of GALNT3 knockdown in H/R-treated rat renal proximal tubular cells. CONCLUSIONS: GALNT3 protected kidney tubular cells in AKI at least partially through O-glycosylation of EGFR.

13.
Chem Soc Rev ; 53(6): 2972-3001, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38345093

RESUMO

Nanofluidic channels with tailored ion transport dynamics are usually used as channels for ion transport, to enable high-performance ion regulation behaviors. The rational construction of nanofluidics and the introduction of external fields are of vital significance to the advancement and development of these ion transport properties. Focusing on the recent advances of nanofluidics, in this review, various dimensional nanomaterials and their derived homogeneous/heterogeneous nanofluidics are first briefly introduced. Then we discuss the basic principles and properties of ion transport in nanofluidics. As the major part of this review, we focus on recent progress in ion transport in nanofluidics regulated by external physical fields (electric field, light, heat, pressure, etc.) and chemical fields (pH, concentration gradient, chemical reaction, etc.), and reveal the advantages and ion regulation mechanisms of each type. Moreover, the representative applications of these nanofluidic channels in sensing, ionic devices, energy conversion, and other areas are summarized. Finally, the major challenges that need to be addressed in this research field and the future perspective of nanofluidics development and practical applications are briefly illustrated.

14.
Med Res Rev ; 44(4): 1404-1445, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38279990

RESUMO

Neurodegenerative diseases (NDs) cause progressive loss of neuron structure and ultimately lead to neuronal cell death. Since the available drugs show only limited symptomatic relief, NDs are currently considered as incurable. This review will illustrate the principal roles of the signaling systems of cyclic adenosine and guanosine 3',5'-monophosphates (cAMP and cGMP) in the neuronal functions, and summarize expression/activity changes of the associated enzymes in the ND patients, including cyclases, protein kinases, and phosphodiesterases (PDEs). As the sole enzymes hydrolyzing cAMP and cGMP, PDEs are logical targets for modification of neurodegeneration. We will focus on PDE inhibitors and their potentials as disease-modifying therapeutics for the treatment of Alzheimer's disease, Parkinson's disease, and Huntington's disease. For the overlapped but distinct contributions of cAMP and cGMP to NDs, we hypothesize that dual PDE inhibitors, which simultaneously regulate both cAMP and cGMP signaling pathways, may have complementary and synergistic effects on modifying neurodegeneration and thus represent a new direction on the discovery of ND drugs.


Assuntos
Doenças Neurodegenerativas , Inibidores de Fosfodiesterase , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Inibidores de Fosfodiesterase/uso terapêutico , Inibidores de Fosfodiesterase/farmacologia , Animais , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Transdução de Sinais/efeitos dos fármacos
15.
Immunology ; 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39385432

RESUMO

Dysfunctional immune regulation contributes to the pathogenesis of food allergy (FA). The mechanism behind regulatory B-cell dysfunction is unclear. CpG has immune regulatory functions. The purpose of this study is to use CpG to recover the immune suppressive functions of B cells in mice with FA. An FA mouse model was created using ovalbumin as the specific antigen. Flow cytometry was used to isolate B cells from the intestinal tissues. The immune regulatory functions of B cells were assessed using immunological approaches. The results showed that the FA response was linked to low IL-10 levels in gut lavage fluids of FA mice. FA mouse intestinal B cells produced lower amounts of IL-10 as compared with B cells isolated from naïve control mice. Impaired immune suppressive functions were observed in B cells isolated from the FA mouse intestine. The inducibility of the Il10 expression in naïve B cells of the intestine of FA mice was defective. The induction of Il10 expression in FA B cells could be restored by CpG through regulating the methylation status of the Cmip promoter. CpG promoted the therapeutic efficacy of allergen specific immunotherapy by restoring the induction of IL-10+ B cells in the intestine. The expression of Il10 in B cells of the FA mouse intestine was impaired. Administration of CpG could restore the expression of Il10 in B cells in the intestine and promote immunotherapy for FA.

16.
J Am Chem Soc ; 146(28): 19303-19309, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38970779

RESUMO

Sulfur hexafluoride (SF6) is extensively employed in the power industry. However, its emissions significantly contribute to the greenhouse effect. The direct recovery of high purity SF6 from industrial waste gases would benefit its sustainable use, yet this represents a considerable challenge. Herein, we report the enrichment of SF6 from SF6/N2 mixtures via adsorptive separation in a stable Co(II)-pyrazolate MOF BUT-53 (BUT: Beijing University of Technology), which features dynamic molecular traps. BUT-53 exhibits an excellent SF6 adsorption uptake of 2.82 mmol/g at 0.1 bar and 298 K, as well as an unprecedented SF6/N2 (10:90) selectivity of 2485. Besides, the remarkable SF6/N2 selectivity of BUT-53 enables recovery of high purity (>99.9%) SF6 from a low concentration (10%) mixture through a breakthrough experiment. The excellent SF6/N2 separation efficiency was also well maintained under humid conditions (RH = 90%) over multiple cycles. Molecular simulation, single-crystal diffraction, and adsorption kinetics studies elucidate the associated adsorption mechanism and water tolerance.

17.
J Am Chem Soc ; 146(8): 5502-5510, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38359445

RESUMO

Glycoproteins account for numerous biological processes including those associated with diseases and infections. The advancement of glycopeptides has emerged as a promising strategy for unraveling biological pathways and discovering novel medicines. In this arena, a key challenge arises from the absence of efficient synthetic strategies to access glycopeptides and glycoproteins. Here, we present a highly concise approach to bridging saccharides with amino acids and peptides through an amide linkage. Our amide-linked C-glycosyl amino acids and peptides are synthesized through cooperative Ni-catalyzed and photoredox processes. The catalytic process generates a glycosyl radical and an amide carbonyl radical, which subsequently combine to yield the C-glycosyl products. The saccharide reaction partners encompass mono-, di-, and trisaccharides. All 20 natural amino acids, peptides, and their derivatives can efficiently undergo glycosylations with yields ranging from acceptable to high, demonstrating excellent stereoselectivities. As a substantial expansion of applications, we have shown that simple C-glycosyl amino acids can function as versatile building units for constructing C-glycopeptides with intricate spatial complexities.


Assuntos
Amidas , Aminoácidos , Níquel/química , Peptídeos , Carboidratos/química , Glicopeptídeos , Glicoproteínas , Catálise
18.
J Am Chem Soc ; 146(38): 26574-26584, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39264946

RESUMO

The ligated boryl radical (LBR) has emerged as a potent tool for activating alkyl halides in radical transformations through halogen-atom transfer (XAT). However, unactivated alkyl chlorides still present an open challenge for this strategy. We herein describe a new activation mode of the LBR for the activation of unactivated alkyl chlorides to construct a C(sp3)-C(sp3) bond. Mechanistic studies reveal that the success of the protocol relies on a radical replacement process between the LBR and unactivated alkyl chloride, forming an alkyl borane intermediate as the alkyl radical precursor. Aided with the additive K3PO4, the alkyl borane then undergoes one-electron oxidation, generating an alkyl radical. The incorporation of the radical replacement activation model to activate unactivated alkyl chlorides significantly enriches LBR chemistry, which has been applied to activate alkyl iodides, alkyl bromides, and activated alkyl chlorides via XAT.

19.
J Am Chem Soc ; 146(8): 5051-5055, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38373353

RESUMO

The construction of quaternary carbon centers via C-C coupling protocols remains challenging. The coupling of tertiary C(sp3) with secondary or tertiary C(sp3) counterparts has been hindered by pronounced steric clashes and many side reactions. Herein, we have successfully developed a type of bisphosphine ligand iron complex-catalyzed coupling reactions of tertiary alkyl halides with secondary alkyl zinc reagents and efficiently realized the coupling reaction between tertiary C(sp3) and secondary C(sp3) with high selectivity for the initial instance, which provided an efficient method for the construction of quaternary carbon centers with high steric hindrance. The combination of an iron catalyst and directing group of the substrate makes the great challenging transformation possible.

20.
J Am Chem Soc ; 146(11): 7210-7215, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38437461

RESUMO

Transition metal-catalyzed reductive cross-couplings to build C-C/Si bonds have been developed, but the reductive cross-coupling to create the C(sp2)-B bond has not been explored. Herein, we describe a nickel-catalyzed reductive cross-coupling between aryl halides and bromoboranes to construct a C(sp2)-B bond. This protocol offers a convenient approach for the synthesis of a wide range of aryl boronate esters, using readily available starting materials. Mechanistic studies indicate that the key to the success of the reaction is the activation of the B-Br bond of bromoboranes with a Lewis base such as 2-MeO-py. The activation ensures that bromoboranes will react with the active nickel(I) catalyst prior to aryl halides, which is different from the sequence of the general nickel-catalyzed reductive C(sp2)-C/Si cross-coupling, where the oxidative addition of an aryl halide proceeds first. Notably, this approach minimizes the production of undesired homocoupling byproduct without the requirement of excessive quantities of either substrate.

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