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1.
Nature ; 585(7826): 545-550, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32968258

RESUMO

To constrain global warming, we must strongly curtail greenhouse gas emissions and capture excess atmospheric carbon dioxide1,2. Regrowing natural forests is a prominent strategy for capturing additional carbon3, but accurate assessments of its potential are limited by uncertainty and variability in carbon accumulation rates2,3. To assess why and where rates differ, here we compile 13,112 georeferenced measurements of carbon accumulation. Climatic factors explain variation in rates better than land-use history, so we combine the field measurements with 66 environmental covariate layers to create a global, one-kilometre-resolution map of potential aboveground carbon accumulation rates for the first 30 years of natural forest regrowth. This map shows over 100-fold variation in rates across the globe, and indicates that default rates from the Intergovernmental Panel on Climate Change (IPCC)4,5 may underestimate aboveground carbon accumulation rates by 32 per cent on average and do not capture eight-fold variation within ecozones. Conversely, we conclude that maximum climate mitigation potential from natural forest regrowth is 11 per cent lower than previously reported3 owing to the use of overly high rates for the location of potential new forest. Although our data compilation includes more studies and sites than previous efforts, our results depend on data availability, which is concentrated in ten countries, and data quality, which varies across studies. However, the plots cover most of the environmental conditions across the areas for which we predicted carbon accumulation rates (except for northern Africa and northeast Asia). We therefore provide a robust and globally consistent tool for assessing natural forest regrowth as a climate mitigation strategy.


Assuntos
Sequestro de Carbono , Carbono/metabolismo , Agricultura Florestal/estatística & dados numéricos , Agricultura Florestal/tendências , Florestas , Mapeamento Geográfico , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Conservação dos Recursos Naturais , Coleta de Dados , Recuperação e Remediação Ambiental , Aquecimento Global/prevenção & controle , Internacionalidade , Cinética
2.
Proc Natl Acad Sci U S A ; 120(13): e2216796120, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36943877

RESUMO

Programmed-death ligand 1 (PD-L1) and its receptor programmed cell death 1 (PD-1) mediate T cell-dependent immunity against tumors. The abundance of cell surface PD-L1 is a key determinant of the efficacy of immune checkpoint blockade therapy targeting PD-L1. However, the regulation of cell surface PD-L1 is still poorly understood. Here, we show that lysosomal degradation of PD-L1 is regulated by O-linked N-acetylglucosamine (O-GlcNAc) during the intracellular trafficking pathway. O-GlcNAc modifies the hepatocyte growth factor-regulated tyrosine kinase substrate (HGS), a key component of the endosomal sorting machinery, and subsequently inhibits its interaction with intracellular PD-L1, leading to impaired lysosomal degradation of PD-L1. O-GlcNAc inhibition activates T cell-mediated antitumor immunity in vitro and in immune-competent mice in a manner dependent on HGS glycosylation. Combination of O-GlcNAc inhibition with PD-L1 antibody synergistically promotes antitumor immune response. We also designed a competitive peptide inhibitor of HGS glycosylation that decreases PD-L1 expression and enhances T cell-mediated immunity against tumor cells. Collectively, our study reveals a link between O-GlcNAc and tumor immune evasion, and suggests strategies for improving PD-L1-mediated immune checkpoint blockade therapy.


Assuntos
Antígeno B7-H1 , Evasão Tumoral , Animais , Camundongos , Antígeno B7-H1/metabolismo , Inibidores de Checkpoint Imunológico/metabolismo , Lisossomos/metabolismo , Linhagem Celular Tumoral
3.
Acc Chem Res ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872074

RESUMO

ConspectusSophisticated genetic networks play a pivotal role in orchestrating cellular responses through intricate signaling pathways across diverse environmental conditions. Beyond the inherent complexity of natural cellular signaling networks, the construction of artificial signaling pathways (ASPs) introduces a vast array of possibilities for reshaping cellular responses, enabling programmable control of living organisms. ASPs can be integrated with existing cellular networks and redirect output responses as desired, allowing seamless communication and coordination with other cellular processes, thereby achieving designable transduction within cells. Among diversified ASPs, establishing connections between originally independent endogenous genes is of particular significance in modifying the genetic networks, so that cells can be endowed with new capabilities to sense and deal with abnormal factors related to differentiated gene expression (i.e., solve the issues of the aberrant gene expression induced by either external or internal stimuli). In a typical scenario, the two genes X and Y in the cell are originally expressed independently. After the introduction of an ASP, changes in the expression of gene X may exert a designed impact on gene Y, subsequently inducing the cellular response related to gene Y. If X represents a disease signal and Y serves as a therapeutic module, the introduction of the ASP empowers cells with a new spontaneous defense system to handle potential risks, which holds great potential for both fundamental and translational studies.In this Account, we primarily review our endeavors in the construction of RNA-mediated ASPs between endogenous genes that can respond to differentiated RNA expression. In contrast to other molecules that may be restricted to specific pathways, synthetic RNA circuits can be easily utilized and expanded as a general platform for constructing ASPs with a high degree of programmability and tunability for diversified functionalities through predictable Watson-Crick base pairing. We first provide an overview of recent advancements in RNA-based genetic circuits, encompassing but not limited to utilization of RNA toehold switches, siRNA and CRISPR systems. Despite notable progress, most reported RNA circuits have to contain at least one exogenous RNA X as input or one engineered RNA Y as a target, which is not suitable for establishing endogenous gene connections. While exogenous RNAs can be engineered and controlled as desired, constructing a general and efficient platform for manipulation of naturally occurring RNAs poses a formidable challenge, especially for the mammalian system. With a focus on this goal, we are devoted to developing efficient strategies to manipulate cell responses by establishing RNA-mediated ASPs between endogenous genes, particularly in mammalian cells. Our step-by-step progress in engineering customized cell signaling circuits, from bacterial cells to mammalian cells, from gene expression regulation to phenotype control, and from small RNA to long mRNA of low abundance and more complex secondary structures, is systematically described. Finally, future perspectives and potential applications of these RNA-mediated ASPs between endogenous genes are also discussed.

4.
Nucleic Acids Res ; 51(14): 7691-7703, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37395400

RESUMO

Construction of synthetic circuits that can reprogram genetic networks and signal pathways is a long-term goal for manipulation of biosystems. However, it is still highly challenging to build artificial genetic communications among endogenous RNA species due to their sequence independence and structural diversities. Here we report an RNA-based synthetic circuit that can establish regulatory linkages between expression of endogenous genes in both Escherichiacoli and mammalian cells. This design employs a displacement-assembly approach to modulate the activity of guide RNA for function control of CRISPR/Cas9. Our experiments demonstrate the great effectiveness of this RNA circuit for building artificial connections between expression of originally unrelated genes. Both exogenous and naturally occurring RNAs, including small/microRNAs and long mRNAs, are capable of controlling expression of another endogenous gene through this approach. Moreover, an artificial signal pathway inside mammalian cells is also successfully established to control cell apoptosis through our designed synthetic circuit. This study provides a general strategy for constructing synthetic RNA circuits, which can introduce artificial connections into the genetic networks of mammalian cells and alter the cellular phenotypes.


Assuntos
Sistemas CRISPR-Cas , MicroRNAs , Animais , Sistemas CRISPR-Cas/genética , Genes Sintéticos , Redes Reguladoras de Genes/genética , RNA Mensageiro , Edição de Genes , Mamíferos/genética
5.
J Cell Mol Med ; 28(1): e18026, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37961985

RESUMO

In the previous study, we found that the oral sodium valproate (SVP) increased the relative abundance of Akkermansia muciniphila (A. muciniphila) in rats, and plasma aspartate transaminase (AST) and alanine aminotransferase (ALT) activities were positively correlated with A. muciniphila levels. This study aimed to further investigate the role of A. muciniphila in SVP-induced hepatotoxicity by orally supplementing rats with the representative strain of A. muciniphila, A. muciniphila MucT. Additionally, the fresh faeces were incubated anaerobically with SVP to investigate the effect of SVP on faecal A. muciniphila in the absence of host influence. Results showed that A. muciniphila MucT ameliorated the hepatotoxicity and upregulation of A. muciniphila induced by SVP. SVP also induced a noteworthy elevation of A. muciniphila level in vitro, supporting the observation in vivo. Therefore, we speculate that A. muciniphila MucT may be a potential therapeutic strategy for SVP-induced hepatotoxicity. In addition, the increased A. muciniphila induced by SVP may differ from A. muciniphila MucT, but further evidence is needed. These findings provide new insights into the relationships between A. muciniphila and SVP-induced hepatotoxicity, highlighting the potential for different A. muciniphila strains to have distinct or even opposing effects on SVP-induced hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Ácido Valproico , Ratos , Animais , Regulação para Cima , Verrucomicrobia/fisiologia , Akkermansia
6.
J Am Chem Soc ; 146(15): 10934-10942, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38581437

RESUMO

Hydroxylamine (HA, NH2OH) is a critical feedstock in the production of various chemicals and materials, and its efficient and sustainable synthesis is of great importance. Electroreduction of nitrate on Cu-based catalysts has emerged as a promising approach for green ammonia (NH3) production, but the electrosynthesis of HA remains challenging due to overreduction of HA to NH3. Herein, we report the first work on ketone-mediated HA synthesis using nitrate in water. A metal-organic-framework-derived Cu catalyst was developed to catalyze the reaction. Cyclopentanone (CP) was used to capture HA in situ to form CP oxime (CP-O) with C═N bonds, which is prone to hydrolysis. HA could be released easily after electrolysis, and CP was regenerated. It was demonstrated that CP-O could be formed with an excellent Faradaic efficiency of 47.8%, a corresponding formation rate of 34.9 mg h-1 cm-2, and a remarkable carbon selectivity of >99.9%. The hydrolysis of CP-O to release HA and CP regeneration was also optimized, resulting in 96.1 mmol L-1 of HA stabilized in the solution, which was significantly higher than direct nitrate reduction. Detailed in situ characterizations, control experiments, and theoretical calculations revealed the catalyst surface reconstruction and reaction mechanism, which showed that the coexistence of Cu0 and Cu+ facilitated the protonation and reduction of *NO2 and *NH2OH desorption, leading to the enhancement for HA production.

7.
J Am Chem Soc ; 146(10): 6665-6674, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38412223

RESUMO

RNA-cleaving ribozymes are promising candidates as general tools of RNA interference (RNAi) in gene manipulation. However, compared with other RNA systems, such as siRNA and CRISPR technologies, the ribozyme tools are still far from broad applications on RNAi due to their poor performance in the cellular context. In this work, we report an efficient RNAi tool based on chemically modified hammerhead ribozyme (HHR). By the introduction of an intramolecular linkage into the minimal HHR to reconstruct the distal interaction within the tertiary ribozyme structure, this cross-linked HHR exhibits efficient RNA substrate cleavage activities with almost no sequence constraint. Cellular experiments suggest that both exogenous and endogenous RNA expression can be dramatically knocked down by this HHR tool with levels comparable to those of siRNA. Unlike the widely applied protein-recruiting RNA systems (siRNA and CRISPR), this ribozyme tool functions solely on RNA itself with great simplicity, which may provide a new approach for gene manipulation in both fundamental and translational studies.


Assuntos
RNA Catalítico , RNA Catalítico/química , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Processamento de Proteína Pós-Traducional , Conformação de Ácido Nucleico
8.
Crit Rev Eukaryot Gene Expr ; 34(3): 49-59, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38305288

RESUMO

OBJECTIVE: Kinesin family proteins (KIFs) play crucial roles in human tumorigenesis and progression. This study aimed to investigate the expression and association of Kinesin family member 20B (KIF20B) with lung adenocarcinoma (LUAD). METHODS: RNA-seq data from LUAD patients (n = 535) were extracted from TCGA. KIF20B expression was compared between tumor tissues and controls, and between different stages of the disease. Survival and Cox regression analyses were performed, as well as in vitro cellular experiments on A549 cells. RESULTS: KIF20B is upregulated in LUAD tumor tissues compared with controls and is higher in advanced stages. Patients with high expression of KIF20B have shorter survival times. KIF20B is an independent risk factor for the prognosis of LUAD. High KIF20B expression samples were enriched in signaling pathways related to tumor progression. si-KIF20B transfection reduced migration and invasion of A549 cells and increased apoptosis. The expression of p53 and Bax proteins was upregulated by si-KIF20B, while Bcl-2 was down-regulated. DISCUSSION: This study reveals that high KIF20B expression is an independent risk factor for the poor prognosis of LUAD. The inhibition of KIF20B might be of great value for suppressing LUAD progression.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Cinesinas/genética , Cinesinas/metabolismo , Proliferação de Células , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/metabolismo , Fatores de Risco , Regulação Neoplásica da Expressão Gênica
9.
Crit Rev Eukaryot Gene Expr ; 34(5): 69-79, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38842205

RESUMO

Gastric cancer is a most malignancy in digestive tract worldwide. This study aimed to investigate the roles of protein arginine methyltransferase 6 (PRMT6) in gastric cancer. Immunohistochemistry was performed to detect PRMT6 expression in gastric tumors. Real-time transcriptase-quantitative polymerase chain reaction (RT-qPCR) was used to detected mRNA levels. Protein expression was determined using western blot. Gastric cancer cells were co-cultured with CD8+ T cells. Colony formation assay was performed to detect cell proliferation. Flow cytometry was performed to determine CD8+ T cell function and tumor cell apoptosis. PRMT6 was overexpressed in gastric tumors. High level of PRMT6 predicted poor outcomes of gastric cancer patients and inhibition of CD8+ T cell infiltration. PRMT6 promoted proliferation of CD8+ T cells and enhanced its tumor killing ability. Moreover, PRMT6 upregulated annexin A1 (ANXA1) and promoted ANXA1 protein stability. ANXA1 overexpression suppressed the proliferation of CD8+ T cells and promoted tumor cell survival. PRMT6 functions as an oncogene in gastric cancer. PRMT6-mediated protein stability inhibits the infiltration of CD8+ T cells, resulting in immune evasion of gastric cancer. The PRMT6-ANXA1 may be a promising strategy for gastric cancer.


Assuntos
Anexina A1 , Linfócitos T CD8-Positivos , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Proteína-Arginina N-Metiltransferases , Neoplasias Gástricas , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/metabolismo , Humanos , Proteína-Arginina N-Metiltransferases/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Anexina A1/genética , Anexina A1/metabolismo , Linhagem Celular Tumoral , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Regulação para Cima , Apoptose , Evasão Tumoral/genética , Masculino , Evasão da Resposta Imune , Feminino , Proteínas Nucleares
10.
Artigo em Inglês | MEDLINE | ID: mdl-38906440

RESUMO

BACKGROUND AND AIMS: The global rise of chronic hepatitis B (CHB) superimposed on hepatic steatosis (HS) warrants non-invasive, precise tools for assessing fibrosis progression. This study leveraged machine learning (ML) to develop diagnostic models for advanced fibrosis and cirrhosis in this patient population. METHODS: Treatment-naive CHB patients with concurrent HS who underwent liver biopsy in ten medical centers were enrolled as a training cohort and an independent external validation cohort (NCT05766449). Six ML models were implemented to predict advanced fibrosis and cirrhosis. The final models, derived from Shapley Additive exPlanations, were compared to Fibrosis-4 Index (FIB-4), Nonalcoholic fatty liver disease Fibrosis Score (NFS), and Aspartate transaminase to platelet ratio index (APRI) using the area under receiver operating characteristic curve (AUROC), and decision curve analysis (DCA). RESULTS: Of 1,198 eligible patients, the random forest (RF) model achieved AUROCs of 0.778 [95% confidence interval (CI) 0.749-0.807] for diagnosing advanced fibrosis (RF-AF model) and 0.777 (95%CI 0.748-0.806) for diagnosing cirrhosis (RF-C model) in the training cohort, and maintained high AUROCs in the validation cohort. In the training cohort, the RF-AF model obtained an AUROC of 0.825 (95% CI 0.787-0.862) in patients with HBV DNA ≥105 IU/ml, and RF-C model had an AUROC of 0.828 (95% CI 0.774-0.883) in female patients. The two models outperformed FIB-4, NFS, and APRI in the training cohort, and also performed well in the validation cohort. CONCLUSION: The RF models provide reliable, non-invasive tools for identifying advanced fibrosis and cirrhosis in CHB patients with concurrent HS, offering a significant advancement in the co-management of the two diseases.

11.
BMC Plant Biol ; 24(1): 293, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632540

RESUMO

BACKGROUND: Pulsatilla saxatilis, a new species of the genus Pulsatilla has been discovered. The morphological information of this species has been well described, but its chloroplast genome characteristics and comparison with species of the same genus remain to be reported. RESULTS: Our results showed that the total length of chloroplast (cp.) genome of P. saxatilis is 162,659 bp, with a GC content of 37.5%. The cp. genome contains 134 genes, including 90 known protein-coding genes, 36 tRNA genes, and 8 rRNA genes. P. saxatilis demonstrated similar characteristics to other species of genus Pulsatilla. Herein, we compared cp. genomes of 10 species, including P. saxatilis, and found that the cp. genomes of the genus Pulsatilla are extremely similar, with a length of 162,322-163,851 bp. Furthermore, The SSRs of Pulsatilla ranged from 10 to 22 bp in length. Among the four structural regions of the cp. genome, most long repeats and SSRs were detected in the LSC region, followed by that in the SSC region, and least in IRA/ IRB regions. The most common types of long repeats were forward and palindromic repeats, followed by reverse repeats, and only a few complementary repeats were found in 10 cp. genomes. We also analyzed nucleotide diversity and identified ccsA_ndhD, rps16_trnK-UUU, ccsA, and rbcL, which could be used as potential molecular markers for identification of Pulsatilla species. The results of the phylogenetic tree constructed by connecting the sequences of high variation regions were consistent with those of the cp. gene phylogenetic tree, and the species more closely related to P. saxatilis was identified as the P. campanella. CONCLUSION: It was determined that the closest species to P. saxatilis is P. campanella, which is the same as the conclusion based on pollen grain characteristics, but different from the P. chinensis determined based on morphological characteristics. By revealing information on the chloroplast characteristics, development, and evolution of the cp. genome and the potential molecular markers, this study provides effective molecular data regarding the evolution, genetic diversity, and species identification of the genus Pulsatilla.


Assuntos
Genoma de Cloroplastos , Pulsatilla , Animais , Filogenia , Espécies em Perigo de Extinção , Pulsatilla/genética , Cloroplastos/genética
12.
Small ; 20(11): e2308209, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37880867

RESUMO

Orientation guidance has shown its cutting edges in electrodeposition modulation to promote Zn anode stability toward commercialized standards. Nevertheless, large-scale orientational deposition is handicapped by the competition between Zn-ion reduction and mass transfer. Herein, a holistic electrolyte additive protocol is put forward via incorporating bio-derived dextrin molecules into a zinc sulfate electrolyte bath. Electrochemical tests in combination with molecular dynamics simulations demonstrate the alleviation of concentration polarization throughout accelerating Zn2+ diffusion and retarding their reduction. The predominant (101) texture on inert current collectors (i.e., Cu, Ti, and stainless steel) and (101)/(002) textures on Zn foils afford homogeneous electrical field distribution, which is contributed by the work difference to form the 2D nucleus and the adsorption of dextrin molecules, respectively. Consequently, the symmetric cell harvests a longevous cycling lifespan of over 4000 h at 0.5 mA cm-2 /0.5 mAh cm-2 while the Zn@Cu electrode sustains for 240 h at a high depth of discharge of 40%.

13.
Small ; : e2400013, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433394

RESUMO

Ruddlesden-Popper (RP) interface with defined stacking structure will fundamentally influence the optoelectronic performances of lead-halide perovskite (LHP) materials and devices. However, it remains challenging to observe the atomic local structures in LHPs, especially for multi-dimensional RP interface hidden inside the nanocrystal. In this work, the advantages of two imaging modes in scanning transmission electron microscopy (STEM), including high-angle annular dark field (HAADF) and integrated differential phase contrast (iDPC) STEM, are successfully combined to study the bulk and local structures of inorganic and organic/inorganic hybrid LHP nanocrystals. Then, the multi-dimensional RP interfaces in these LHPs are atomically resolved with clear gap and blurred transition region, respectively. In particular, the complex interface by the RP stacking in 3D directions can be analyzed in 2D projected image. Finally, the phase transition, ion missing, and electronic structures related to this interface are investigated. These results provide real-space evidence for observing and analyzing atomic multi-dimensional RP interfaces, which may help to better understand the structure-property relation of LHPs, especially their complex local structures.

14.
Small ; : e2400498, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38863125

RESUMO

Sodium-ion battery (SIB) is a candidate for the stationary energy storage systems because of the low cost and high abundance of sodium. However, the energy density and lifespan of SIBs suffer severely from the irreversible consumption of the Na-ions for the formation of the solid electrolyte interphase (SEI) layer and other side reactions on the electrodes. Here, Na3.5C6O6 is proposed as an air-stable high-efficiency sacrificial additive in the cathode to compensate for the lost sodium. It is characteristic of low desodiation (oxidation) potential (3.4-3.6 V vs. Na+/Na) and high irreversible desodiation capacity (theoretically 378 mAh g-1). The feasibility of using Na3.5C6O6 as a sodium compensation additive is verified with the improved electrochemical performances of a Na2/3Ni1/3Mn1/3Ti1/3O2ǀǀhard carbon cells and cells using other cathode materials. In addition, the structure of Na3.5C6O6 and its desodiation path are also clarified on the basis of comprehensive physical characterizations and the density functional theory (DFT) calculations. This additive decomposes completely to supply abundant Na ions during the initial charge without leaving any electrochemically inert species in the cathode. Its decomposition product C6O6 enters the carbonate electrolyte without bringing any detectable negative effects. These findings open a new avenue for elevating the energy density and/or prolonging the lifetime of the high-energy-density secondary batteries.

15.
Planta ; 260(1): 9, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795149

RESUMO

MAIN CONCLUSION: The secondary metabolic conversion of monolignans to sesquilignans/dilignans was closely related to seed germination and seedling establishment in Arctium lappa. Arctium lappa plants are used as a kind of traditional Chinese medicines for nearly 1500 years, and so far, only a few studies have put focus on the key secondary metabolic changes during seed germination and seedling establishment. In the current study, a combined approach was used to investigate the correlation among secondary metabolites, plant hormone signaling, and transcriptional profiles at the early critical stages of A. lappa seed germination and seedling establishment. Of 50 metabolites in methonolic extracts of A. lappa samples, 35 metabolites were identified with LC-MS/MS and 15 metabolites were identified with GC-MS. Their qualitative properties were examined according to the predicted chemical structures. The quantitative analysis was performed for deciphering their metabolic profiles, discovering that the secondary metabolic conversion from monolignans to sesquilignans/dilignans was closely correlated to the initiation of A. lappa seed germination and seedling establishment. Furthermore, the critical transcriptional changes in primary metabolisms, translational regulation at different cellular compartments, and multiple plant hormone signaling pathways were revealed. In addition, the combined approach provides unprecedented insights into key regulatory mechanisms in both gene transcription and secondary metabolites besides many known primary metabolites during seed germination of an important traditional Chinese medicinal plant species. The results not only provide new insights to understand the regulation of key medicinal components of 'ARCTII FRUCTUS', arctiin and arctigenin at the stages of seed germination and seedling establishment, but also potentially spur the development of seed-based cultivation in A. lappa plants.


Assuntos
Arctium , Germinação , Lignanas , Sementes , Arctium/genética , Arctium/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Lignanas/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Regulação da Expressão Gênica de Plantas , Espectrometria de Massas em Tandem , Lignina/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Metabolismo Secundário
16.
New Phytol ; 241(6): 2480-2494, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296835

RESUMO

Drought stress profoundly hampers both plant growth and crop yield. To combat this, plants have evolved intricate transcriptional regulation mechanisms as a pivotal strategy. Through a genetic screening with rice genome-scale mutagenesis pool under drought stress, we identified an APETALA2/Ethylene Responsive Factor, namely OsERF103, positively responds to drought tolerance in rice. Combining chromatin immunoprecipitation sequencing and RNA sequencing analyses, we pinpointed c. 1000 genes directly influenced by OsERF103. Further results revealed that OsERF103 interacts with Stress-responsive NAC1 (SNAC1), a positive regulator of drought tolerance in rice, to synergistically regulate the expression of key drought-related genes, such as OsbZIP23. Moreover, we found that OsERF103 recruits a Su(var)3-9,enhancer of zeste and trithorax-domain group protein 705, which encodes a histone 3 lysine 4 (H3K4)-specific methyltransferase to specifically affect the deposition of H3K4me3 at loci like OsbZIP23 and other genes linked to dehydration responses. Additionally, the natural alleles of OsERF103 are selected during the domestication of both indica and japonica rice varieties and exhibit significant geographic distribution. Collectively, our findings have unfurled a comprehensive mechanistic framework underlying the OsERF103-mediated cascade regulation of drought response. This discovery not only enhances our understanding of drought signaling but also presents a promising avenue for the genetic improvement of drought-tolerant rice cultivars.


Assuntos
Oryza , Oryza/metabolismo , Estresse Fisiológico/genética , Secas , Plantas Geneticamente Modificadas/metabolismo , Sequências Reguladoras de Ácido Nucleico , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
17.
J Med Virol ; 96(4): e29613, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38634477

RESUMO

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a new nomenclature proposed in 2023. We aimed to compare the diagnostic efficacy of noninvasive tests (NITs) for advanced fibrosis under different nomenclatures in patients with chronic hepatitis B (CHB). A total of 844 patients diagnosed with CHB and concurrent steatotic liver disease (SLD) by liver biopsy were retrospectively enrolled and divided into four groups. The performances of fibrosis-4 (FIB-4), gamma-glutamyl transpeptidase to platelet ratio index (GPRI), aspartate aminotransferase to platelet ratio index (APRI), and liver stiffness measurement (LSM) were compared among the four groups. The four NITs showed similar diagnostic efficacy for nonalcoholic fatty liver disease (NAFLD), MASLD, and metabolic dysfunction-associated fatty liver disease (MAFLD) in patients with CHB with advanced fibrosis. LSM showed the most stable accuracy for NAFLD (AUC = 0.842), MASLD (AUC = 0.846), and MAFLD (AUC = 0.863) compared with other NITs (p < 0.05). Among the four NITs, APRI (AUC = 0.841) and GPRI (AUC = 0.844) performed best in patients with CHB & MetALD (p < 0.05). The cutoff value for GPRI in patients with CHB & MetALD was higher than that in the other three groups, while further comparisons of NITs at different fibrosis stages showed that the median GPRI of CHB & MetALD (1.113) at F3-4 was higher than that in the CHB & MASLD group (0.508) (p < 0.05). Current NITs perform adequately in patients with CHB and SLD; however, alterations in cutoff values for CHB & MetALD need to be noted.


Assuntos
Hepatite B Crônica , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatite B Crônica/complicações , Cirrose Hepática/patologia , Estudos Retrospectivos , Biomarcadores , Biópsia , Aspartato Aminotransferases , Curva ROC , Fígado/patologia
18.
J Med Virol ; 96(4): e29569, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38549467

RESUMO

The natural progression of chronic hepatitis B virus (HBV) infection is dynamic, but the longitudinal landscape of HBV serological markers with host antiviral immune response relevant hepatic inflammatory damage remains undetermined. To this issue, we studied the association of HBV serological markers with the severity of hepatic inflammatory damage and enumerated HBV-specific T cells using the cultured enzyme-linked immune absorbent spot (ELISpot). Five hundred and twenty-four treatment-naïve chronic HBV infection patients were enrolled. The Spearman correlation analysis revealed that in hepatitis B e antigen (HBeAg)-positive patients, all HBV virologic indicators negatively correlated with liver inflammatory damage and fibrosis (p < 0.01). Stronger correlations were accessed in the subgroup of HBeAg-positive patients with HBV DNA > 2 × 106 IU/mL (p < 0.01), whereas negative correlations disappeared in patients with HBV DNA ≤ 2 × 106 IU/mL. Surprisingly, in HBeAg-negative patients, the HBV DNA level was positively correlated with the hepatic inflammatory damage (p < 0.01). The relationship between type Ⅱ interferon genes expression and HBV DNA levels also revealed a direct shift from the initial negative to positive in HBeAg-positive patients with HBV DNA declined below 2 × 106 IU/mL. The number of HBV-specific T cells were identified by interferon γ ELISpot assays and showed a significant increase from HBeAg-positive to HBeAg-negative group. The host's anti-HBV immunity remains effective in HBeAg-positive patients with HBV DNA levels exceeding 2 × 106 IU/mL, as it efficiently eliminates infected hepatocytes and inhibits HBV replication. However, albeit the increasing number of HBV-specific T cells, the host antiviral immune response shifts towards dysfunctional when the HBV DNA load drops below this threshold, which causes more pathological damage and disease progression.


Assuntos
Hepatite B Crônica , Humanos , Vírus da Hepatite B/genética , Antígenos E da Hepatite B/análise , DNA Viral , Imunidade
19.
Hepatology ; 78(4): 1079-1091, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37114494

RESUMO

BACKGROUND AND AIMS: The intratumoral microbiome has been reported to regulate the development and progression of cancers. We aimed to characterize intratumoral microbial heterogeneity (IMH) and establish microbiome-based molecular subtyping of HBV-related HCC to elucidate the correlation between IMH and HCC tumorigenesis. APPROACH AND RESULTS: A case-control study was designed to investigate microbial landscape and characteristic microbial signatures of HBV-related HCC tissues adopting metagenomics next-generation sequencing. Microbiome-based molecular subtyping of HCC tissues was established by nonmetric multidimensional scaling. The tumor immune microenvironment of 2 molecular subtypes was characterized by EPIC and CIBERSORT based on RNA-seq and verified by immunohistochemistry. The gene set variation analysis was adopted to explore the crosstalk between the immune and metabolism microenvironment. A prognosis-related gene risk signature between 2 subtypes was constructed by the weighted gene coexpression network analysis and the Cox regression analysis and then verified by the Kaplan-Meier survival curve.IMH demonstrated in HBV-related HCC tissues was comparably lower than that in chronic hepatitis tissues. Two microbiome-based HCC molecular subtypes, defined as bacteria- and virus-dominant subtypes, were established and significantly correlated with discrepant clinical-pathologic features. Higher infiltration of M2 macrophage was detected in the bacteria-dominant subtype with to the virus-dominant subtype, accompanied by multiple upregulated metabolism pathways. Furthermore, a 3-gene risk signature containing CSAG4 , PIP4P2 , and TOMM5 was filtered out, which could predict the clinical prognosis of HCC patients accurately using the Cancer Genome Atlas data. CONCLUSIONS: Microbiome-based molecular subtyping demonstrated IMH of HBV-related HCC was correlated with a disparity in clinical-pathologic features and tumor microenvironment (TME), which might be proposed as a biomarker for prognosis prediction of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Estudos de Casos e Controles , Vírus da Hepatite B/genética , Neoplasias Hepáticas/etiologia , Microambiente Tumoral
20.
Drug Metab Dispos ; 52(2): 126-134, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38050044

RESUMO

Cytochrome P450 3A (CYP3A) participates in the metabolism of more than 30% of clinical drugs. The vast intra- and inter-individual variations in CYP3A activity pose great challenges to drug development and personalized medicine. It has been disclosed that human CYP3A4 and CYP3A7 are exclusively responsible for the tertiary oxidations of deoxycholic acid (DCA) and glycodeoxycholic acid (GDCA) regioselectivity at C-1ß and C-5ß This work aimed to compare the 1ß- and 5ß-hydroxylation of DCA and GDCA as potential in vitro CYP3A index reactions in both human liver microsomes and recombinant P450 enzymes. The results demonstrated that the metabolic activity of DCA 1ß- and 5ß-hydroxylation was 5-10 times higher than that of GDCA, suggesting that 1ß-hydroxyglycodeoxycholic acid and 5ß-hydroxyglycodeoxycholic acid may originate from DCA oxidation followed by conjugation in humans. Metabolic phenotyping data revealed that DCA 1ß-hydroxylation, DCA 5ß-hydroxylation, and GDCA 5ß-hydroxylation were predominantly catalyzed by CYP3A4 (>80%), while GDCA 1ß-hydroxylation had approximately equal contributions from CYP3A4 (41%) and 3A7 (58%). Robust Pearson correlation was established for the intrinsic clearance of DCA 1ß- and 5ß-hydroxylation with midazolam (MDZ) 1'- and 4-hydroxylation in fourteen single donor microsomes. Although DCA 5ß-hydroxylation exhibited a stronger correlation with MDZ oxidation, DCA 1ß-hydroxylation exhibited higher reactivity than DCA 5ß-hydroxylation. It is therefore suggested that DCA 1ß- and 5ß-hydroxylations may serve as alternatives to T 6ß-hydroxylation as in vitro CYP3A index reactions. SIGNIFICANCE STATEMENT: The oxidation of DCA and GDCA is primarily catalyzed by CYP3A4 and CYP3A7. This work compared the 1ß- and 5ß-hydroxylation of DCA and GDCA as in vitro index reactions to assess CYP3A activities. It was disclosed that the metabolic activity of DCA 1ß- and 5ß-hydroxylation was 5-10 times higher than that of GDCA. Although DCA 1ß-hydroxylation exhibited higher metabolic activity than DCA 5ß-hydroxylation, DCA 5ß-hydroxylation demonstrated stronger correlation with MDZ oxidation than DCA 1ß-hydroxylation in individual liver microsomes.


Assuntos
Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450 , Humanos , Citocromo P-450 CYP3A/metabolismo , Hidroxilação , Ácido Glicodesoxicólico/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Oxirredução , Microssomos Hepáticos/metabolismo , Midazolam/metabolismo
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