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1.
Nature ; 625(7995): 516-522, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38233617

RESUMO

Perovskite solar cells (PSCs) comprise a solid perovskite absorber sandwiched between several layers of different charge-selective materials, ensuring unidirectional current flow and high voltage output of the devices1,2. A 'buffer material' between the electron-selective layer and the metal electrode in p-type/intrinsic/n-type (p-i-n) PSCs (also known as inverted PSCs) enables electrons to flow from the electron-selective layer to the electrode3-5. Furthermore, it acts as a barrier inhibiting the inter-diffusion of harmful species into or degradation products out of the perovskite absorber6-8. Thus far, evaporable organic molecules9,10 and atomic-layer-deposited metal oxides11,12 have been successful, but each has specific imperfections. Here we report a chemically stable and multifunctional buffer material, ytterbium oxide (YbOx), for p-i-n PSCs by scalable thermal evaporation deposition. We used this YbOx buffer in the p-i-n PSCs with a narrow-bandgap perovskite absorber, yielding a certified power conversion efficiency of more than 25%. We also demonstrate the broad applicability of YbOx in enabling highly efficient PSCs from various types of perovskite absorber layer, delivering state-of-the-art efficiencies of 20.1% for the wide-bandgap perovskite absorber and 22.1% for the mid-bandgap perovskite absorber, respectively. Moreover, when subjected to ISOS-L-3 accelerated ageing, encapsulated devices with YbOx exhibit markedly enhanced device stability.

2.
Mol Cell ; 82(10): 1781-1783, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35594841

RESUMO

Caspases are often considered the final checkpoint for a pathogen to save its replicative niche from collapsing after cell death signaling has been initiated in response to infection. Two recent works (Li et al., 2021; Peng et al., 2022) found that pathogens inhibit host cell death by inactivating multiple caspases with a novel posttranslational modification.


Assuntos
Caspases , Interações Hospedeiro-Patógeno , Caspases/genética , Caspases/metabolismo , Morte Celular , Replicação do DNA
3.
Nature ; 620(7976): 1047-1053, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37459895

RESUMO

Zygotic genome activation (ZGA) activates the quiescent genome to enable the maternal-to-zygotic transition1,2. However, the identity of transcription factors that underlie mammalian ZGA in vivo remains elusive. Here we show that OBOX, a PRD-like homeobox domain transcription factor family (OBOX1-OBOX8)3-5, are key regulators of mouse ZGA. Mice deficient for maternally transcribed Obox1/2/5/7 and zygotically expressed Obox3/4 had a two-cell to four-cell arrest, accompanied by impaired ZGA. The Obox knockout defects could be rescued by restoring either maternal and zygotic OBOX, which suggests that maternal and zygotic OBOX redundantly support embryonic development. Chromatin-binding analysis showed that Obox knockout preferentially affected OBOX-binding targets. Mechanistically, OBOX facilitated the 'preconfiguration' of RNA polymerase II, as the polymerase relocated from the initial one-cell binding targets to ZGA gene promoters and distal enhancers. Impaired polymerase II preconfiguration in Obox mutants was accompanied by defective ZGA and chromatin accessibility transition, as well as aberrant activation of one-cell polymerase II targets. Finally, ectopic expression of OBOX activated ZGA genes and MERVL repeats in mouse embryonic stem cells. These data thus demonstrate that OBOX regulates mouse ZGA and early embryogenesis.


Assuntos
Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Genoma , Proteínas de Homeodomínio , Fatores de Transcrição , Zigoto , Animais , Camundongos , Cromatina/genética , Cromatina/metabolismo , Desenvolvimento Embrionário/genética , Elementos Facilitadores Genéticos/genética , Genoma/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Mutação , Regiões Promotoras Genéticas/genética , RNA Polimerase II/metabolismo , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zigoto/metabolismo
4.
Mol Cell ; 77(1): 164-179.e6, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31732457

RESUMO

The family of bacterial SidE enzymes catalyzes non-canonical phosphoribosyl-linked (PR) serine ubiquitination and promotes infectivity of Legionella pneumophila. Here, we describe identification of two bacterial effectors that reverse PR ubiquitination and are thus named deubiquitinases for PR ubiquitination (DUPs; DupA and DupB). Structural analyses revealed that DupA and SidE ubiquitin ligases harbor a highly homologous catalytic phosphodiesterase (PDE) domain. However, unlike SidE ubiquitin ligases, DupA displays increased affinity to PR-ubiquitinated substrates, which allows DupA to cleave PR ubiquitin from substrates. Interfering with DupA-ubiquitin binding switches its activity toward SidE-type ligase. Given the high affinity of DupA to PR-ubiquitinated substrates, we exploited a catalytically inactive DupA mutant to trap and identify more than 180 PR-ubiquitinated host proteins in Legionella-infected cells. Proteins involved in endoplasmic reticulum (ER) fragmentation and membrane recruitment to Legionella-containing vacuoles (LCV) emerged as major SidE targets. The global map of PR-ubiquitinated substrates provides critical insights into host-pathogen interactions during Legionella infection.


Assuntos
Enzimas Desubiquitinantes/metabolismo , Serina/metabolismo , Ubiquitina/metabolismo , Ubiquitinação/fisiologia , Células A549 , Proteínas de Bactérias/metabolismo , Domínio Catalítico/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Retículo Endoplasmático/metabolismo , Células HEK293 , Células HeLa , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Legionella pneumophila/patogenicidade , Doença dos Legionários/metabolismo , Vacúolos/metabolismo
5.
Nature ; 594(7862): 195-200, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34108697

RESUMO

In the last few decades, topological phase1-11 has emerged as a new classification of matter states beyond the Ginzburg-Landau symmetry-breaking paradigm. The underlying global invariant is usually well characterized by integers, such as Chern numbers or winding numbers-the Abelian charges12-15. Very recently, researchers proposed the notion of non-Abelian topological charges16-19, which possess non-commutative and fruitful braiding structures with multiple (more than one) bandgaps tangled together. Here we experimentally observe the non-Abelian topological charges in a time-reversal and inversion-symmetric transmission line network. The quaternion-valued non-Abelian topological charges are clearly mapped onto an eigenstate-frame sphere. Moreover, we find a non-Abelian quotient relation that provides a global perspective on the distribution of edge/domain-wall states. Our work opens the door towards characterization and manipulation of non-Abelian topological charges, which may lead to interesting observables such as trajectory-dependent Dirac/Weyl node collisions in two-dimensional systems16,17,20, admissible nodal line configurations in three dimensions16,19,20, and may provide insight into certain strongly correlated phases of twisted bilayer graphene21.

6.
Proc Natl Acad Sci U S A ; 121(6): e2318174121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38289955

RESUMO

Atomically dispersed catalysts are a promising alternative to platinum group metal catalysts for catalyzing the oxygen reduction reaction (ORR), while limited durability during the electrocatalytic process severely restricts their practical application. Here, we report an atomically dispersed Co-doped carbon-nitrogen bilayer catalyst with unique dual-axial Co-C bonds (denoted as Co/DACN) by a smart phenyl-carbon-induced strategy, realizing highly efficient electrocatalytic ORR in both alkaline and acidic media. The corresponding half-wave potential for ORR is up to 0.85 and 0.77 V (vs. reversible hydrogen electrode (RHE)) in 0.5 M H2SO4 and 0.1 M KOH, respectively, representing the best ORR activity among all non-noble metal catalysts reported to date. Impressively, the Zn-air battery (ZAB) equipped with Co/DACN cathode achieves outstanding durability after 1,688 h operation at 10 mA cm-2 with a high current density (154.2 mA cm-2) and a peak power density (210.1 mW cm-2). Density functional theory calculations reveal that the unique dual-axial cross-linking Co-C bonds of Co/DACN significantly enhance the stability during ORR and also facilitate the 4e- ORR pathway by forming a joint electron pool due to the improved interlayer electron mobility. We believe that axial engineering opens a broad avenue to develop high-performance heterogeneous electrocatalysts for advanced energy conversion and storage.

7.
PLoS Pathog ; 20(5): e1011783, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38739652

RESUMO

Legionella pneumophila strains harboring wild-type rpsL such as Lp02rpsLWT cannot replicate in mouse bone marrow-derived macrophages (BMDMs) due to induction of extensive lysosome damage and apoptosis. The bacterial factor directly responsible for inducing such cell death and the host factor involved in initiating the signaling cascade that leads to lysosome damage remain unknown. Similarly, host factors that may alleviate cell death induced by these bacterial strains have not yet been investigated. Using a genome-wide CRISPR/Cas9 screening, we identified Hmg20a and Nol9 as host factors important for restricting strain Lp02rpsLWT in BMDMs. Depletion of Hmg20a protects macrophages from infection-induced lysosomal damage and apoptosis, allowing productive bacterial replication. The restriction imposed by Hmg20a was mediated by repressing the expression of several endo-lysosomal proteins, including the small GTPase Rab7. We found that SUMOylated Rab7 is recruited to the bacterial phagosome via SulF, a Dot/Icm effector that harbors a SUMO-interacting motif (SIM). Moreover, overexpression of Rab7 rescues intracellular growth of strain Lp02rpsLWT in BMDMs. Our results establish that L. pneumophila exploits the lysosomal network for the biogenesis of its phagosome in BMDMs.


Assuntos
Legionella pneumophila , Lisossomos , Macrófagos , Fagossomos , Proteínas rab de Ligação ao GTP , proteínas de unión al GTP Rab7 , Legionella pneumophila/metabolismo , Legionella pneumophila/genética , Animais , Proteínas rab de Ligação ao GTP/metabolismo , Camundongos , Fagossomos/metabolismo , Fagossomos/microbiologia , Lisossomos/metabolismo , Lisossomos/microbiologia , Macrófagos/microbiologia , Macrófagos/metabolismo , Doença dos Legionários/metabolismo , Doença dos Legionários/microbiologia , Sumoilação , Camundongos Endogâmicos C57BL , Endossomos/metabolismo , Endossomos/microbiologia
8.
Plant Physiol ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833579

RESUMO

The asymmetrical distribution of auxin supports high intensity blue light (HBL)-mediated phototropism. Flavonoids, secondary metabolites induced by blue light and TRANSPARENT TESTA GLABRA1 (TTG1), alter auxin transport. However, the role of TTG1 in HBL-induced phototropism in Arabidopsis (Arabidopsis thaliana) remains unclear. We found that TTG1 regulates HBL-mediated phototropism. HBL-induced degradation of CRYPTOCHROME 1 (CRY1) was repressed in ttg1-1, and depletion of CRY1 rescued the phototropic defects of the ttg1-1 mutant. Moreover, overexpression of CRY1 in a cry1 mutant background led to phototropic defects in response to HBL. These results indicated that CRY1 is involved in the regulation of TTG1-mediated phototropism in response to HBL. Further investigation showed that TTG1 physically interacts with CRY1 via its N-terminus and that the added TTG1 promotes the dimerization of CRY1. The interaction between TTG1 and CRY1 may promote HBL-mediated degradation of CRY1. TTG1 also physically interacted with blue light inhibitor of cryptochrome 1 (BIC1) and Light-Response Bric-a-Brack/Tramtrack/Broad 2 (LRB2), and these interactions either inhibited or promoted their interaction with CRY1. Exogenous gibberellins (GA) and auxins, two key plant hormones that crosstalk with CRY1, may confer the recovery of phototropic defects in the ttg1-1 mutant and CRY1-overexpressing plants. Our results revealed that TTG1 participates in the regulation of HBL-induced phototropism by modulating CRY1 levels, which are coordinated with GA or IAA signaling.

9.
J Immunol ; 210(8): 1031-1042, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36881872

RESUMO

Previous studies have shown that cysteine-reactive drug metabolites bind covalently with protein to activate patient T cells. However, the nature of the antigenic determinants that interact with HLA and whether T cell stimulatory peptides contain the bound drug metabolite has not been defined. Because susceptibility to dapsone hypersensitivity is associated with the expression of HLA-B*13:01, we have designed and synthesized nitroso dapsone-modified, HLA-B*13:01 binding peptides and explored their immunogenicity using T cells from hypersensitive human patients. Cysteine-containing 9-mer peptides with high binding affinity to HLA-B*13:01 were designed (AQDCEAAAL [Pep1], AQDACEAAL [Pep2], and AQDAEACAL [Pep3]), and the cysteine residue was modified with nitroso dapsone. CD8+ T cell clones were generated and characterized in terms of phenotype, function, and cross-reactivity. Autologous APCs and C1R cells expressing HLA-B*13:01 were used to determine HLA restriction. Mass spectrometry confirmed that nitroso dapsone-peptides were modified at the appropriate site and were free of soluble dapsone and nitroso dapsone. APC HLA-B*13:01-restricted nitroso dapsone-modified Pep1- (n = 124) and Pep3-responsive (n = 48) CD8+ clones were generated. Clones proliferated and secreted effector molecules with graded concentrations of nitroso dapsone-modified Pep1 or Pep3. They also displayed reactivity against soluble nitroso dapsone, which forms adducts in situ, but not with the unmodified peptide or dapsone. Cross-reactivity was observed between nitroso dapsone-modified peptides with cysteine residues in different positions in the peptide sequence. These data characterize a drug metabolite hapten CD8+ T cell response in an HLA risk allele-restricted form of drug hypersensitivity and provide a framework for structural analysis of hapten HLA binding interactions.


Assuntos
Dapsona , Hipersensibilidade a Drogas , Humanos , Cisteína , Linfócitos T CD8-Positivos , Antígenos HLA-B , Peptídeos , Haptenos
10.
Nature ; 572(7769): 387-391, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31330531

RESUMO

The bacterial pathogen Legionella pneumophila creates an intracellular niche permissive for its replication by extensively modulating host-cell functions using hundreds of effector proteins delivered by its Dot/Icm secretion system1. Among these, members of the SidE family (SidEs) regulate several cellular processes through a unique phosphoribosyl ubiquitination mechanism that bypasses the canonical ubiquitination machinery2-4. The activity of SidEs is regulated by another Dot/Icm effector known as SidJ5; however, the mechanism of this regulation is not completely understood6,7. Here we demonstrate that SidJ inhibits the activity of SidEs by inducing the covalent attachment of glutamate moieties to SdeA-a member of the SidE family-at E860, one of the catalytic residues that is required for the mono-ADP-ribosyltransferase activity involved in ubiquitin activation2. This inhibition by SidJ is spatially restricted in host cells because its activity requires the eukaryote-specific protein calmodulin (CaM). We solved a structure of SidJ-CaM in complex with AMP and found that the ATP used in this reaction is cleaved at the α-phosphate position by SidJ, which-in the absence of glutamate or modifiable SdeA-undergoes self-AMPylation. Our results reveal a mechanism of regulation in bacterial pathogenicity in which a glutamylation reaction that inhibits the activity of virulence factors is activated by host-factor-dependent acyl-adenylation.


Assuntos
Calmodulina/metabolismo , Ácido Glutâmico/metabolismo , Legionella pneumophila/enzimologia , Legionella pneumophila/metabolismo , Ubiquitinação , ADP-Ribosilação , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Catálise , Domínio Catalítico , Coenzimas/metabolismo , Células HEK293 , Humanos , Legionella pneumophila/citologia , Modelos Moleculares , Ubiquitina/química , Ubiquitina/metabolismo
11.
Proc Natl Acad Sci U S A ; 119(44): e2202931119, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36306330

RESUMO

The electrochemical CO2 reduction reaction (CO2RR) powered by excess zero-carbon-emission electricity to produce especially multicarbon (C2+) products could contribute to a carbon-neutral to carbon-negative economy. Foundational to the rational design of efficient, selective CO2RR electrocatalysts is mechanistic analysis of the best metal catalyst thus far identified, namely, copper (Cu), via quantum mechanical computations to complement experiments. Here, we apply embedded correlated wavefunction (ECW) theory, which regionally corrects the electron exchange-correlation error in density functional theory (DFT) approximations, to examine multiple C-C coupling steps involving adsorbed CO (*CO) and its hydrogenated derivatives on the most ubiquitous facet, Cu(111). We predict that two adsorbed hydrogenated CO species, either *COH or *CHO, are necessary precursors for C-C bond formation. The three kinetically feasible pathways involving these species yield all three possible products: *COH-CHO, *COH-*COH, and *OCH-*OCH. The most kinetically favorable path forms *COH-CHO. In contrast, standard DFT approximations arrive at qualitatively different conclusions, namely, that only *CO and *COH will prevail on the surface and their C-C coupling paths produce only *COH-*COH and *CO-*CO, with a preference for the first product. This work demonstrates the importance of applying qualitatively and quantitatively accurate quantum mechanical method to simulate electrochemistry in order ultimately to shed light on ways to enhance selectivity toward C2+ product formation via CO2RR electrocatalysts.


Assuntos
Dióxido de Carbono , Cobre , Dióxido de Carbono/metabolismo , Catálise , Cobre/química , Eletroquímica , Carbono
12.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34930823

RESUMO

Coxiella burnetii is a bacterial pathogen that replicates within host cells by establishing a membrane-bound niche called the Coxiella-containing vacuole. Biogenesis of this compartment requires effectors of its Dot/Icm type IV secretion system. A large cohort of such effectors has been identified, but the function of most of them remain elusive. Here, by a cell-based functional screening, we identified the effector Cbu0513 (designated as CinF) as an inhibitor of NF-κB signaling. CinF is highly similar to a fructose-1,6-bisphosphate (FBP) aldolase/phosphatase present in diverse bacteria. Further study reveals that unlike its ortholog from Sulfolobus tokodaii, CinF does not exhibit FBP phosphatase activity. Instead, it functions as a protein phosphatase that specifically dephosphorylates and stabilizes IκBα. The IκBα phosphatase activity is essential for the role of CinF in C. burnetii virulence. Our results establish that C. burnetii utilizes a protein adapted from sugar metabolism to subvert host immunity.


Assuntos
Proteínas de Bactérias , Coxiella burnetii , Fosfoproteínas Fosfatases , Febre Q , Transdução de Sinais , Fatores de Virulência , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Chlorocebus aethiops , Coxiella burnetii/genética , Coxiella burnetii/imunologia , Coxiella burnetii/patogenicidade , Células HEK293 , Células HeLa , Humanos , NF-kappa B/genética , NF-kappa B/imunologia , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/imunologia , Febre Q/genética , Febre Q/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Células Vero , Fatores de Virulência/genética , Fatores de Virulência/imunologia
13.
Nano Lett ; 24(5): 1687-1694, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38253561

RESUMO

Revealing the in-depth structure-property relationship and designing specific capacity electrodes are particularly important for supercapacitors. Despite many efforts made to tune the composition and electronic structure of cobalt oxide for pseudocapacitance, insight into the [CoO]6 octahedron from the microstructure is still insufficient. Herein, we present a tunable [CoO]6 octahedron microstructure in LiCoO2 by a chemical delithiation process. The c-strained strain of the [CoO]6 octahedron is induced to form higher valence Co ions, and the (003) crystalline layer spacing increases to allow more rapid participation of OH- in the redox reaction. Interestingly, the specific capacity of L0.75CO2 is nearly four times higher than that of LiCoO2 at 10 mA g-1. The enhanced activity originated from the asymmetric strain [CoO]6 octahedra, resulting in enhanced electronic conductivity and Co-O hybridization for accelerated redox kinetics. This finding provides new insights into the modification strategy for pseudocapacitive transition metal oxides.

14.
J Infect Dis ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669226

RESUMO

BACKGROUND: The role of Gasdermin D (GSDMD) in bloodstream infection (BSI) diagnosis is unknown. METHODS: Serum GSDMD levels were measured in BSI patients. Endothelial cells and PBMCs were isolated, infected with bacteria/fungi, and intracellular/extracellular GSDMD concentrations were measured. An animal model was established to investigate the association between serum GSDMD levels and BSI incidence/progression. RESULTS: ROC curve analysis indicated that GSDMD could be a potential early diagnostic biomarker for BSI (AUC = 0.9885). Combining GSDMD with procalcitonin (PCT) improved the differential diagnosis of Gram-positive and Gram-negative bacteria (AUC = 0.6699, 66.15% specificity), and early diagnosis of Gram-positive bacteria (98.46% sensitivity), while PCT was not significantly elevated. The combined GSDMD and G-test had higher sensitivity (AUC = 0.7174) for differential diagnosis of bacterial and fungal infections, and early detection of fungal infections (98.44% sensitivity). In vitro and in vivo experiments confirmed that GSDMD levels increased significantly within 2 hours, peaked at 16 hours, and exhibited a time-dependent upward trend. CONCLUSIONS: Serum GSDMD, alone or combined with other biomarkers, has potential for early diagnosis and differential diagnosis of BSI caused by various pathogens. This finding offers a new strategy for early detection and treatment of BSI.

15.
J Cell Mol Med ; 28(7): e18221, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38509759

RESUMO

Gliomas are the most common tumours in the central nervous system. In the present study, we aimed to find a promising anti-glioma compound and investigate the underlying molecular mechanism. Glioma cells were subjected to the 50 candidate compounds at a final concentration of 10 µM for 72 h, and CCK-8 was used to evaluate their cytotoxicity. NPS-2143, an antagonist of calcium-sensing receptor (CASR), was selected for further study due to its potent cytotoxicity to glioma cells. Our results showed that NPS-2143 could inhibit the proliferation of glioma cells and induce G1 phase cell cycle arrest. Meanwhile, NPS-2143 could induce glioma cell apoptosis by increasing the caspase-3/6/9 activity. NPS-2143 impaired the immigration and invasion ability of glioma cells by regulating the epithelial-mesenchymal transition process. Mechanically, NPS-2143 could inhibit autophagy by mediating the AKT-mTOR pathway. Bioinformatic analysis showed that the prognosis of glioma patients with low expression of CASR mRNA was better than those with high expression of CASR mRNA. Gene set enrichment analysis showed that CASR was associated with cell adhesion molecules and lysosomes in glioma. The nude mice xenograft model showed NPS-2143 could suppress glioma growth in vivo. In conclusion, NPS-2143 can suppress the glioma progression by inhibiting autophagy.


Assuntos
Glioma , Naftalenos , Proteínas Proto-Oncogênicas c-akt , Animais , Humanos , Camundongos , Apoptose , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Glioma/tratamento farmacológico , Glioma/genética , Glioma/metabolismo , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , Serina-Treonina Quinases TOR/metabolismo , Naftalenos/farmacologia
16.
J Am Chem Soc ; 146(9): 5964-5976, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38381843

RESUMO

Fluorinated ethers have become promising electrolyte solvent candidates for lithium metal batteries (LMBs) because they are endowed with high oxidative stability and high Coulombic efficiencies of lithium metal stripping/plating. Up to now, most reported fluorinated ether electrolytes are -CF3-based, and the influence of ion solvation in modifying degree of fluorination has not been well-elucidated. In this work, we synthesize a hexacyclic coordinated ether (1-methoxy-3-ethoxypropane, EMP) and its fluorinated ether counterparts with -CH2F (F1EMP), -CHF2 (F2EMP), or -CF3 (F3EMP) as terminal group. With lithium bis(fluorosulfonyl)imide as single salt, the solvation structure, Li-ion transport behavior, lithium deposition kinetics, and high-voltage stability of the electrolytes were systematically studied. Theoretical calculations and spectra reveal the gradually reduced solvating power from nonfluorinated EMP to fully fluorinated F3EMP, which leads to decreased ionic conductivity. In contrast, the weakly solvating fluorinated ethers possess higher Li+ transference number and exchange current density. Overall, partially fluorinated -CHF2 is demonstrated as the desired group. Further full cell testing using high-voltage (4.4 V) and high-loading (3.885 mAh cm-2) LiNi0.8Co0.1Mn0.1O2 cathode demonstrates that F2EMP electrolyte enables 80% capacity retention after 168 cycles under limited Li (50 µm) and lean electrolyte (5 mL Ah-1) conditions and 129 cycles under extremely lean electrolyte (1.8 mL Ah-1) and the anode-free conditions. This work deepens the fundamental understanding on the ion transport and interphase dynamics under various degrees of fluorination and provides a feasible approach toward the design of fluorinated ether electrolytes for practical high-voltage LMBs.

17.
Clin Immunol ; 265: 110291, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38908771

RESUMO

Linear IgA bullous dermatosis (LABD) and dermatitis herpetiformis (DH) represent the major subtypes of IgA mediated autoimmune bullous disorders. We sought to understand the disease etiology by using serum proteomics. We assessed 92 organ damage biomarkers in LAB, DH, and healthy controls using the Olink high-throughput proteomics. The positive proteomic serum biomarkers were used to correlate with clinical features and HLA type. Targeted proteomic analysis of IgA deposition bullous disorders vs. controls showed elevated biomarkers. Further clustering and enrichment analyses identified distinct clusters between LABD and DH, highlighting the involvement of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Comparative analysis revealed biomarkers with distinction between LABD and DH and validated in the skin lesion. Finally, qualitative correlation analysis with DEPs suggested six biomarkers (NBN, NCF2, CAPG, FES, BID, and PXN) have better prognosis in DH patients. These findings provide potential biomarkers to differentiate the disease subtype of IgA deposition bullous disease.

18.
EMBO J ; 39(4): e102806, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-31825121

RESUMO

The Legionella pneumophila effector MavC induces ubiquitination of the E2 ubiquitin-conjugating enzyme UBE2N by transglutamination, thereby abolishing its function in the synthesis of K63 -type polyubiquitin chains. The inhibition of UBE2N activity creates a conundrum because this E2 enzyme is important in multiple signaling pathways, including some that are important for intracellular L. pneumophila replication. Here, we show that prolonged inhibition of UBE2N activity by MavC restricts intracellular bacterial replication and that the activity of UBE2N is restored by MvcA, an ortholog of MavC (50% identity) with ubiquitin deamidase activity. MvcA functions to deubiquitinate UBE2N-Ub using the same catalytic triad required for its deamidase activity. Structural analysis of the MvcA-UBE2N-Ub complex reveals a crucial role of the insertion domain in MvcA in substrate recognition. Our study establishes a deubiquitination mechanism catalyzed by a deamidase, which, together with MavC, imposes temporal regulation of the activity of UBE2N during L. pneumophila infection.


Assuntos
Proteínas de Bactérias/metabolismo , Legionella pneumophila/fisiologia , Transdução de Sinais , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina/metabolismo , Proteínas de Bactérias/genética , Células HEK293 , Humanos , Legionella pneumophila/enzimologia , Legionella pneumophila/genética , Legionella pneumophila/patogenicidade , Poliubiquitina/metabolismo , Sistemas de Secreção Tipo IV , Enzimas de Conjugação de Ubiquitina/genética , Ubiquitinação
19.
Genome Res ; 31(1): 13-26, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33328167

RESUMO

Long noncoding RNAs (lncRNAs) have emerged as diverse functional regulators involved in mammalian development; however, large-scale functional investigation of lncRNAs in mammalian spermatogenesis in vivo is lacking. Here, we delineated the global lncRNA expression landscape in mouse spermatogenesis and identified 968 germ cell signature lncRNAs. By combining bioinformatics and functional screening, we identified three functional lncRNAs (Gm4665, 1700027A15Rik, and 1700052I22Rik) that directly influence spermatogenesis in vivo. Knocking down Gm4665 hampered the development of round spermatids into elongating spermatids and disrupted key spermatogenic gene expression. Mechanistically, lncRNA Gm4665 localized in the nucleus of round spermatids and occupied the genomic regulatory region of important spermatogenic genes including Ip6k1 and Akap3 These findings provide a valuable resource and framework for future functional analysis of lncRNAs in spermatogenesis and their potential roles in other biological processes.


Assuntos
Espermatogênese , Animais , Perfilação da Expressão Gênica , Masculino , Camundongos , RNA Longo não Codificante/genética , Espermátides , Espermatogênese/genética , Transcriptoma
20.
Am J Gastroenterol ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38345246

RESUMO

INTRODUCTION: Significant knowledge gaps exist regarding clinicopathological profiling as well as treatment, surveillance, and survival of duodenal neuroendocrine tumors (dNETs). METHODS: We clinicopathologically characterized and identified racial differences among patients with dNETs at a large safety net hospital. Tumor grades were updated based on the World Health Organization 2019 NET classification, and overall survival was determined. RESULTS: We identified 17 dNETs and found no differences in clinicopathologic characteristics across racial groups. Pathological diagnosis was upgraded in 35% of dNETs, and age >65 years significantly shortened overall survival. DISCUSSION: Larger-scale studies are needed to determine the significance of these findings.

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