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1.
Nature ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39236747

RESUMO

Two-terminal monolithic perovskite-silicon tandem solar cells demonstrate huge advantages in power conversion efficiency (PCE) compared to their respective single-junction counterparts1,2. However, suppressing interfacial recombination at the wide-bandgap perovskite/electron transport layer interface, without compromising its superior charge transport performance, remains a significant challenge for perovskite-silicon tandem cells3,4. By exploiting the nanoscale discretely distributed LiF ultrathin layer followed by an additional deposition of diammonium diiodide molecule, we have devised a bilayer intertwined passivation strategy that combines efficient electron extraction with further suppression of nonradiative recombination. We constructed perovskite-silicon tandem devices on double-side textured Czochralski (CZ)-based silicon heterojunction cell, which featured a mildly-textured front surface and a heavily-textured rear surface, leading to simultaneously enhanced photocurrent and uncompromised rear passivation. The resulting perovskite-silicon tandem achieved an independently certified stabilized PCE of 33.89%, accompanied by an impressive fill factor (FF) of 83.0% and an open-circuit voltage (Voc) of nearly 1.97 volts. To our knowledge, this represents the first reported certified efficiency of a two-junction tandem solar cell exceeding the single-junction Shockley-Queisser limit of 33.7%.

2.
Immunity ; 46(6): 992-1004.e5, 2017 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-28636969

RESUMO

RNA interference (RNAi) functions as a potent antiviral immunity in plants and invertebrates; however, whether RNAi plays antiviral roles in mammals remains unclear. Here, using human enterovirus 71 (HEV71) as a model, we showed HEV71 3A protein as an authentic viral suppressor of RNAi during viral infection. When the 3A-mediated RNAi suppression was impaired, the mutant HEV71 readily triggered the production of abundant HEV71-derived small RNAs with canonical siRNA properties in cells and mice. These virus-derived siRNAs were produced from viral dsRNA replicative intermediates in a Dicer-dependent manner and loaded into AGO, and they were fully active in degrading cognate viral RNAs. Recombinant HEV71 deficient in 3A-mediated RNAi suppression was significantly restricted in human somatic cells and mice, whereas Dicer deficiency rescued HEV71 infection independently of type I interferon response. Thus, RNAi can function as an antiviral immunity, which is induced and suppressed by a human virus, in mammals.


Assuntos
Enterovirus Humano A/imunologia , Infecções por Enterovirus/imunologia , Imunidade , Interferência de RNA , RNA Viral/imunologia , Animais , Proteínas Argonautas/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Enterovirus Humano A/genética , Células HEK293 , Humanos , Mamíferos , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Mutação/genética , Ribonuclease III/metabolismo , Proteínas Virais/imunologia
3.
Proc Natl Acad Sci U S A ; 120(19): e2219994120, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37126689

RESUMO

Glutamate (Glu) is the major excitatory transmitter in the nervous system. Impairment of its vesicular release by ß-amyloid (Aß) oligomers is thought to participate in pathological processes leading to Alzheimer's disease. However, it remains unclear whether soluble Aß42 oligomers affect intravesicular amounts of Glu or their release in the brain, or both. Measurements made in this work on single Glu varicosities with an amperometric nanowire Glu biosensor revealed that soluble Aß42 oligomers first caused a dramatic increase in vesicular Glu storage and stimulation-induced release, accompanied by a high level of parallel spontaneous exocytosis, ultimately resulting in the depletion of intravesicular Glu content and greatly reduced release. Molecular biology tools and mouse models of Aß amyloidosis have further established that the transient hyperexcitation observed during the primary pathological stage is mediated by an altered behavior of VGLUT1 responsible for transporting Glu into synaptic vesicles. Thereafter, an overexpression of Vps10p-tail-interactor-1a, a protein that maintains spontaneous release of neurotransmitters by selective interaction with t-SNAREs, resulted in a depletion of intravesicular Glu content, triggering advanced-stage neuronal malfunction. These findings are expected to open perspectives for remediating Aß42-induced neuronal hyperactivity and neuronal degeneration.


Assuntos
Doença de Alzheimer , Ácido Glutâmico , Camundongos , Animais , Ácido Glutâmico/metabolismo , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Neurônios/metabolismo , Encéfalo/metabolismo , Fragmentos de Peptídeos/metabolismo
4.
Plant J ; 119(4): 1859-1879, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38923625

RESUMO

In the field, necrosis area induced by pathogens is usually surrounded by a red circle in apple fruits. However, the underlying molecular mechanism of this phenomenon remains unclear. In this study, we demonstrated that accumulated salicylic acid (SA) induced by fungal infection promoted anthocyanin biosynthesis through MdNPR1-MdTGA2.2 module in apple (Malus domestica). Inoculating apple fruits with Valsa mali or Botryosphaeria dothidea induced a red circle surrounding the necrosis area, which mimicked the phenotype observed in the field. The red circle accumulated a high level of anthocyanins, which was positively correlated with SA accumulation stimulated by fungal invasion. Further analysis showed that SA promoted anthocyanin biosynthesis in a dose-dependent manner in both apple calli and fruits. We next demonstrated that MdNPR1, a master regulator of SA signaling, positively regulated anthocyanin biosynthesis in both apple and Arabidopsis. Moreover, MdNPR1 functioned as a co-activator to interact with and enhance the transactivation activity of MdTGA2.2, which could directly bind to the promoters of anthocyanin biosynthetic and regulatory genes to promote their transcription. Suppressing expression of either MdNPR1 or MdTGA2.2 inhibited coloration of apple fruits, while overexpressing either of them significantly promoted fruit coloration. Finally, we revealed that silencing either MdNPR1 or MdTGA2.2 in apple fruits repressed SA-induced fruit coloration. Therefore, our data determined that fungal-induced SA promoted anthocyanin biosynthesis through MdNPR1-MdTGA2.2 module, resulting in a red circle surrounding the necrosis area in apple fruits.


Assuntos
Antocianinas , Ascomicetos , Frutas , Regulação da Expressão Gênica de Plantas , Malus , Doenças das Plantas , Proteínas de Plantas , Ácido Salicílico , Malus/microbiologia , Malus/genética , Malus/metabolismo , Ácido Salicílico/metabolismo , Antocianinas/biossíntese , Antocianinas/metabolismo , Ascomicetos/fisiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Frutas/microbiologia , Frutas/metabolismo , Frutas/genética , Arabidopsis/microbiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
5.
Mol Biol Evol ; 41(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38768215

RESUMO

High mountains harbor a considerable proportion of biodiversity, but we know little about how diverse plants adapt to the harsh environment. Here we finished a high-quality genome assembly for Dasiphora fruticosa, an ecologically important plant distributed in the Qinghai-Tibetan Plateau and lowland of the Northern Hemisphere, and resequenced 592 natural individuals to address how this horticulture plant adapts to highland. Demographic analysis revealed D. fruticosa underwent a bottleneck after Naynayxungla Glaciation. Selective sweep analysis of two pairs of lowland and highland populations identified 63 shared genes related to cell wall organization or biogenesis, cellular component organization, and dwarfism, suggesting parallel adaptation to highland habitats. Most importantly, we found that stronger purging of estimated genetic load due to inbreeding in highland populations apparently contributed to their adaptation to the highest mountain. Our results revealed how plants could tolerate the extreme plateau, which could provide potential insights for species conservation and crop breeding.


Assuntos
Genoma de Planta , Seleção Genética , Adaptação Fisiológica/genética , Altitude
6.
PLoS Biol ; 20(1): e3001522, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35061665

RESUMO

Nonalcoholic fatty liver disease (NAFLD) affects approximately a quarter of the population worldwide, and persistent overnutrition is one of the major causes. However, the underlying molecular basis has not been fully elucidated, and no specific drug has been approved for this disease. Here, we identify a regulatory mechanism that reveals a novel function of Rab2A in the progression of NAFLD based on energy status and PPARγ. The mechanistic analysis shows that nutrition repletion suppresses the phosphorylation of AMPK-TBC1D1 signaling, augments the level of GTP-bound Rab2A, and then increases the protein stability of PPARγ, which ultimately promotes the hepatic accumulation of lipids in vitro and in vivo. Furthermore, we found that blocking the AMPK-TBC1D1 pathway in TBC1D1S231A-knock-in (KI) mice led to a markedly increased GTP-bound Rab2A and subsequent fatty liver in aged mice. Our studies also showed that inhibition of Rab2A expression alleviated hepatic lipid deposition in western diet-induced obesity (DIO) mice by reducing the protein level of PPARγ and the expression of PPARγ target genes. Our findings not only reveal a new molecular mechanism regulating the progression of NAFLD during persistent overnutrition but also have potential implications for drug discovery to combat this disease.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Proteínas rab de Ligação ao GTP/metabolismo , Envelhecimento , Animais , Regulação da Expressão Gênica , Técnicas de Introdução de Genes , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/fisiologia , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Proteínas rab de Ligação ao GTP/genética
7.
Nano Lett ; 24(1): 331-338, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38108571

RESUMO

Solar-driven photothermal catalytic H2 production from lignocellulosic biomass was achieved by using 1T-2H MoS2 with tunable Lewis acidic sites as catalysts in an alkaline aqueous solution, in which the number of Lewis acidic sites derived from the exposed Mo edges of MoS2 was successfully regulated by both the formation of an edge-terminated 1T-2H phase structure and tunable layer number. Owing to the abundant Lewis acidic sites for the oxygenolysis of lignocellulosic biomass, the 1T-2H MoS2 catalyst shows high photothermal catalytic lignocellulosic biomass-to-H2 transformation performance in polar wood chips, bamboo, rice straw corncobs, and rice hull aqueous solutions, and the highest H2 generation rate and solar-to-H2 (STH) efficiency respectively achieves 3661 µmol·h-1·g-1 and 0.18% in the polar wood chip system under 300 W Xe lamp illumination. This study provides a sustainable and cost-effective method for the direct transformation of renewable lignocellulosic biomass to H2 fuel driven by solar energy.

8.
J Am Chem Soc ; 146(37): 25445-25450, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39235150

RESUMO

To date, it remains challenging to precisely and efficiently construct structurally intriguing polycarbocycles with densely packed stereocenters in organic synthesis. Niduterpenoid B, a naturally occurring ERα inhibitor, exemplifies this complexity with its intricate polycyclic network comprising 5 cyclopentane and 1 cyclopropane rings, featuring 13 contiguous stereocenters, including 4 all-carbon quaternary centers. In this work, we describe the first total synthesis of niduterpenoid B using a structural reorganization strategy. Key features include the following: (1) an efficient methoxy-controlled cascade reaction that precisely forges a highly functionalized tetraquinane (A-D rings) bearing sterically hindered contiguous quaternary stereocenters; (2) a rhodium-catalyzed [1 + 2] cycloaddition that facilitates the construction of a strained 3/5 bicycle (E-F rings) angularly fused with ring D.

9.
J Med Virol ; 96(5): e29635, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38682660

RESUMO

Guangzhou has been the city most affected by the dengue virus (DENV) in China, with a predominance of DENV serotype 1 (DENV-1). Viral factors such as dengue serotype and genotype are associated with severe dengue (SD). However, none of the studies have investigated the relationship between DENV-1 genotypes and SD. To understand the association between DENV-1 genotypes and SD, the clinical manifestations of patients infected with different genotypes were investigated. A total of 122 patients with confirmed DENV-1 genotype infection were recruited for this study. The clinical manifestations, laboratory tests, and levels of inflammatory mediator factors were statistically analyzed to investigate the characteristics of clinical manifestations and immune response on the DENV-1 genotype. In the case of DENV-1 infection, the incidence of SD with genotype V infection was significantly higher than that with genotype I infection. Meanwhile, patients infected with genotype V were more common in ostealgia and bleeding significantly. In addition, levels of inflammatory mediator factors including IFN-γ, TNF-α, IL-10, and soluble vascular cell adhesion molecule 1 were higher in patients with SD infected with genotype V. Meanwhile, the concentrations of regulated upon activation normal T-cell expressed and secreted and growth-related gene alpha were lower in patients with SD infected with genotype V. The higher incidence of SD in patients infected with DENV-1 genotype V may be attributed to elevated cytokines and adhesion molecules, along with decreased chemokines.


Assuntos
Vírus da Dengue , Genótipo , Sorogrupo , Dengue Grave , Humanos , Vírus da Dengue/genética , Vírus da Dengue/classificação , China/epidemiologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Dengue Grave/virologia , Dengue Grave/epidemiologia , Adulto Jovem , Citocinas/sangue , Adolescente , Idoso , Incidência , Criança , Dengue/virologia , Dengue/epidemiologia
10.
Mol Ecol ; 33(5): e17268, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38230514

RESUMO

Ecological divergence due to habitat difference plays a prominent role in the formation of new species, but the genetic architecture during ecological speciation and the mechanism underlying phenotypic divergence remain less understood. Two wild ancestors of rice (Oryza rufipogon and Oryza nivara) are a progenitor-derivative species pair with ecological divergence and provide a unique system for studying ecological adaptation/speciation. Here, we constructed a high-resolution linkage map and conducted a quantitative trait locus (QTL) analysis of 19 phenotypic traits using an F2 population generated from a cross between the two Oryza species. We identified 113 QTLs associated with interspecific divergence of 16 quantitative traits, with effect sizes ranging from 1.61% to 34.1% in terms of the percentage of variation explained (PVE). The distribution of effect sizes of QTLs followed a negative exponential, suggesting that a few genes of large effect and many genes of small effect were responsible for the phenotypic divergence. We observed 18 clusters of QTLs (QTL hotspots) on 11 chromosomes, significantly more than that expected by chance, demonstrating the importance of coinheritance of loci/genes in ecological adaptation/speciation. Analysis of effect direction and v-test statistics revealed that interspecific differentiation of most traits was driven by divergent natural selection, supporting the argument that ecological adaptation/speciation would proceed rapidly under coordinated selection on multiple traits. Our findings provide new insights into the understanding of genetic architecture of ecological adaptation and speciation in plants and help effective manipulation of specific genes or gene cluster in rice breeding.


Assuntos
Oryza , Oryza/genética , Melhoramento Vegetal , Mapeamento Cromossômico , Fenótipo , Locos de Características Quantitativas/genética
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