ABSTRACT
The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/-) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection.
Subject(s)
Amino Acyl-tRNA Synthetases/metabolism , Disease Resistance/immunology , Host-Pathogen Interactions/immunology , Virus Diseases/immunology , Virus Diseases/metabolism , Amino Acyl-tRNA Synthetases/chemistry , Amino Acyl-tRNA Synthetases/genetics , Animals , Antiviral Agents/pharmacology , Disease Models, Animal , Immunity, Innate , Mice , Mice, Knockout , Peptides/pharmacology , Phosphorylation , Protein Binding , RNA Virus Infections/immunology , RNA Virus Infections/metabolism , RNA Virus Infections/virology , RNA Viruses/drug effects , RNA Viruses/immunology , RNA-Binding Proteins/metabolism , Signal Transduction , Ubiquitination , Virus Diseases/virology , Virus ReplicationABSTRACT
Tight regulation of Toll-like receptor (TLR)-mediated inflammatory responses is important for innate immunity. Here, we show that T-cell death-associated gene 51 (TDAG51/PHLDA1) is a novel regulator of the transcription factor FoxO1, regulating inflammatory mediator production in the lipopolysaccharide (LPS)-induced inflammatory response. TDAG51 induction by LPS stimulation was mediated by the TLR2/4 signaling pathway in bone marrow-derived macrophages (BMMs). LPS-induced inflammatory mediator production was significantly decreased in TDAG51-deficient BMMs. In TDAG51-deficient mice, LPS- or pathogenic Escherichia coli infection-induced lethal shock was reduced by decreasing serum proinflammatory cytokine levels. The recruitment of 14-3-3ζ to FoxO1 was competitively inhibited by the TDAG51-FoxO1 interaction, leading to blockade of FoxO1 cytoplasmic translocation and thereby strengthening FoxO1 nuclear accumulation. TDAG51/FoxO1 double-deficient BMMs showed significantly reduced inflammatory mediator production compared with TDAG51- or FoxO1-deficient BMMs. TDAG51/FoxO1 double deficiency protected mice against LPS- or pathogenic E. coli infection-induced lethal shock by weakening the systemic inflammatory response. Thus, these results indicate that TDAG51 acts as a regulator of the transcription factor FoxO1, leading to strengthened FoxO1 activity in the LPS-induced inflammatory response.
Subject(s)
Escherichia coli , Lipopolysaccharides , Mice , Animals , 14-3-3 Proteins , Transcription Factors/genetics , Inflammation MediatorsABSTRACT
Histone deacetylase 3 (HDAC3) is a crucial epigenetic modulator essential for various developmental and physiological functions. Although its dysfunction is increasingly recognized in abnormal phenotypes, to our knowledge, there have been no established reports of human diseases directly linked to HDAC3 dysfunction. Using trio exome sequencing and extensive phenotypic analysis, we correlated heterozygous de novo variants in HDAC3 with a neurodevelopmental disorder having variable clinical presentations, frequently associated with intellectual disability, developmental delay, epilepsy, and musculoskeletal abnormalities. In a cohort of six individuals, we identified missense variants in HDAC3 (c.277G>A [p.Asp93Asn], c.328G>A [p.Ala110Thr], c.601C>T [p.Pro201Ser], c. 797T>C [p.Leu266Ser], c.799G>A [p.Gly267Ser], and c.1075C>T [p.Arg359Cys]), all located in evolutionarily conserved sites and confirmed as de novo. Experimental studies identified defective deacetylation activity in the p.Asp93Asn, p.Pro201Ser, p.Leu266Ser, and p.Gly267Ser variants, positioned near the enzymatic pocket. In addition, proteomic analysis employing co-immunoprecipitation revealed that the disrupted interactions with molecules involved in the CoREST and NCoR complexes, particularly in the p.Ala110Thr variant, consist of a central pathogenic mechanism. Moreover, immunofluorescence analysis showed diminished nuclear to cytoplasmic fluorescence ratio in the p.Ala110Thr, p.Gly267Ser, and p.Arg359Cys variants, indicating impaired nuclear localization. Taken together, our study highlights that de novo missense variants in HDAC3 are associated with a broad spectrum of neurodevelopmental disorders, which emphasizes the complex role of HDAC3 in histone deacetylase activity, multi-protein complex interactions, and nuclear localization for proper physiological functions. These insights open new avenues for understanding the molecular mechanisms of HDAC3-related disorders and may inform future therapeutic strategies.
Subject(s)
Epigenesis, Genetic , Histone Deacetylases , Mutation, Missense , Neurodevelopmental Disorders , Humans , Histone Deacetylases/genetics , Histone Deacetylases/metabolism , Mutation, Missense/genetics , Neurodevelopmental Disorders/genetics , Male , Female , Child, Preschool , Child , Intellectual Disability/genetics , Exome Sequencing , Adolescent , Developmental Disabilities/genetics , Phenotype , Infant , Nuclear Receptor Co-Repressor 1/genetics , Nuclear Receptor Co-Repressor 1/metabolismABSTRACT
H1 linker histones are the most abundant chromatin-binding proteins1. In vitro studies indicate that their association with chromatin determines nucleosome spacing and enables arrays of nucleosomes to fold into more compact chromatin structures. However, the in vivo roles of H1 are poorly understood2. Here we show that the local density of H1 controls the balance of repressive and active chromatin domains by promoting genomic compaction. We generated a conditional triple-H1-knockout mouse strain and depleted H1 in haematopoietic cells. H1 depletion in T cells leads to de-repression of T cell activation genes, a process that mimics normal T cell activation. Comparison of chromatin structure in normal and H1-depleted CD8+ T cells reveals that H1-mediated chromatin compaction occurs primarily in regions of the genome containing higher than average levels of H1: the chromosome conformation capture (Hi-C) B compartment and regions of the Hi-C A compartment marked by PRC2. Reduction of H1 stoichiometry leads to decreased H3K27 methylation, increased H3K36 methylation, B-to-A-compartment shifting and an increase in interaction frequency between compartments. In vitro, H1 promotes PRC2-mediated H3K27 methylation and inhibits NSD2-mediated H3K36 methylation. Mechanistically, H1 mediates these opposite effects by promoting physical compaction of the chromatin substrate. Our results establish H1 as a critical regulator of gene silencing through localized control of chromatin compaction, 3D genome organization and the epigenetic landscape.
Subject(s)
Chromatin Assembly and Disassembly , Chromatin/genetics , Epigenesis, Genetic , Histones/metabolism , Animals , CD8-Positive T-Lymphocytes/metabolism , Cell Differentiation/genetics , Chromatin/chemistry , Chromatin/metabolism , Enhancer of Zeste Homolog 2 Protein/metabolism , Female , Gene Silencing , Histones/chemistry , Lymphocyte Activation/genetics , Male , Methylation , Mice , Mice, KnockoutABSTRACT
High-quality and complete reference genome assemblies are fundamental for the application of genomics to biology, disease, and biodiversity conservation. However, such assemblies are available for only a few non-microbial species1-4. To address this issue, the international Genome 10K (G10K) consortium5,6 has worked over a five-year period to evaluate and develop cost-effective methods for assembling highly accurate and nearly complete reference genomes. Here we present lessons learned from generating assemblies for 16 species that represent six major vertebrate lineages. We confirm that long-read sequencing technologies are essential for maximizing genome quality, and that unresolved complex repeats and haplotype heterozygosity are major sources of assembly error when not handled correctly. Our assemblies correct substantial errors, add missing sequence in some of the best historical reference genomes, and reveal biological discoveries. These include the identification of many false gene duplications, increases in gene sizes, chromosome rearrangements that are specific to lineages, a repeated independent chromosome breakpoint in bat genomes, and a canonical GC-rich pattern in protein-coding genes and their regulatory regions. Adopting these lessons, we have embarked on the Vertebrate Genomes Project (VGP), an international effort to generate high-quality, complete reference genomes for all of the roughly 70,000 extant vertebrate species and to help to enable a new era of discovery across the life sciences.
Subject(s)
Genome , Genomics/methods , Vertebrates/genetics , Animals , Birds , Gene Library , Genome Size , Genome, Mitochondrial , Haplotypes , High-Throughput Nucleotide Sequencing , Molecular Sequence Annotation , Sequence Alignment , Sequence Analysis, DNA , Sex Chromosomes/geneticsABSTRACT
As the process that silences gene expression ensues during development, the stage is set for the activity of Polycomb-repressive complex 2 (PRC2) to maintain these repressed gene profiles. PRC2 catalyzes a specific histone posttranslational modification (hPTM) that fosters chromatin compaction. PRC2 also facilitates the inheritance of this hPTM through its self-contained "write and read" activities, key to preserving cellular identity during cell division. As these changes in gene expression occur without changes in DNA sequence and are inherited, the process is epigenetic in scope. Mutants of mammalian PRC2 or of its histone substrate contribute to the cancer process and other diseases, and research into these aberrant pathways is yielding viable candidates for therapeutic targeting. The effectiveness of PRC2 hinges on its being recruited to the proper chromatin sites; however, resolving the determinants to this process in the mammalian case was not straightforward and thus piqued the interest of many in the field. Here, we chronicle the latest advances toward exposing mammalian PRC2 and its high maintenance.
Subject(s)
Epigenesis, Genetic , Gene Expression Regulation , Polycomb Repressive Complex 2/genetics , Polycomb Repressive Complex 2/metabolism , Animals , Chromatin/metabolism , Humans , Mutation , Neoplasms/genetics , Neoplasms/physiopathology , Protein Transport , Research/trendsABSTRACT
The histone methyltransferase activity of PRC2 is central to the formation of H3K27me3-decorated facultative heterochromatin and gene silencing. In addition, PRC2 has been shown to automethylate its core subunits, EZH1/EZH2 and SUZ12. Here, we identify the lysine residues at which EZH1/EZH2 are automethylated with EZH2-K510 and EZH2-K514 being the major such sites in vivo. Automethylated EZH2/PRC2 exhibits a higher level of histone methyltransferase activity and is required for attaining proper cellular levels of H3K27me3. While occurring independently of PRC2 recruitment to chromatin, automethylation promotes PRC2 accessibility to the histone H3 tail. Intriguingly, EZH2 automethylation is significantly reduced in diffuse intrinsic pontine glioma (DIPG) cells that carry a lysine-to-methionine substitution in histone H3 (H3K27M), but not in cells that carry either EZH2 or EED mutants that abrogate PRC2 allosteric activation, indicating that H3K27M impairs the intrinsic activity of PRC2. Our study demonstrates a PRC2 self-regulatory mechanism through its EZH1/2-mediated automethylation activity.
Subject(s)
Glioma/enzymology , Glioma/genetics , Histones/metabolism , Child , Enzyme Activation , Gene Silencing , Histones/genetics , Humans , Lysine/metabolism , Methylation , Polycomb Repressive Complex 2/metabolism , Protein Subunits/genetics , Protein Subunits/metabolismABSTRACT
PRC2 is a therapeutic target for several types of cancers currently undergoing clinical trials. Its activity is regulated by a positive feedback loop whereby its terminal enzymatic product, H3K27me3, is specifically recognized and bound by an aromatic cage present in its EED subunit. The ensuing allosteric activation of the complex stimulates H3K27me3 deposition on chromatin. Here we report a stepwise feedback mechanism entailing key residues within distinctive interfacing motifs of EZH2 or EED that are found to be mutated in cancers and/or Weaver syndrome. PRC2 harboring these EZH2 or EED mutants manifested little activity in vivo but, unexpectedly, exhibited similar chromatin association as wild-type PRC2, indicating an uncoupling of PRC2 activity and recruitment. With genetic and chemical tools, we demonstrated that targeting allosteric activation overrode the gain-of-function effect of EZH2Y646X oncogenic mutations. These results revealed critical implications for the regulation and biology of PRC2 and a vulnerability in tackling PRC2-addicted cancers.
Subject(s)
Allosteric Regulation/physiology , Chromatin/metabolism , Polycomb Repressive Complex 2/metabolism , Abnormalities, Multiple/metabolism , Cell Line, Tumor , Congenital Hypothyroidism/metabolism , Craniofacial Abnormalities/metabolism , Enhancer of Zeste Homolog 2 Protein/metabolism , Hand Deformities, Congenital/metabolism , Histones/metabolism , Humans , Neoplasms/metabolismABSTRACT
The maintenance of gene expression patterns during metazoan development is achieved, in part, by the actions of polycomb repressive complex 2 (PRC2). PRC2 catalyzes mono-, di-, and trimethylation of histone H3 at lysine 27 (H3K27), with H3K27me2/3 being strongly associated with silenced genes. We demonstrate that EZH1 and EZH2, the two mutually exclusive catalytic subunits of PRC2, are differentially activated by various mechanisms. Whereas both PRC2-EZH1 and PRC2-EZH2 are able to catalyze mono- and dimethylation, only PRC2-EZH2 is strongly activated by allosteric modulators and specific chromatin substrates to catalyze trimethylation of H3K27 in mouse embryonic stem cells (mESCs). However, we also show that a PRC2-associated protein, AEBP2, can stimulate the activity of both complexes through a mechanism independent of and additive to allosteric activation. These results have strong implications regarding the cellular requirements for and the accompanying adjustments in PRC2 activity, given the differential expression of EZH1 and EZH2 upon cellular differentiation.
Subject(s)
Polycomb Repressive Complex 2/metabolism , Animals , Catalysis , Cell Line , Chromatin/metabolism , DNA-Binding Proteins/metabolism , Enhancer of Zeste Homolog 2 Protein/metabolism , HEK293 Cells , Histones/metabolism , Humans , Lysine/metabolism , Methylation , MiceABSTRACT
Polycomb repressive complex 2 (PRC2) maintains gene silencing by catalyzing methylation of histone H3 at lysine 27 (H3K27me2/3) within chromatin. By designing a system whereby PRC2-mediated repressive domains were collapsed and then reconstructed in an inducible fashion in vivo, a two-step mechanism of H3K27me2/3 domain formation became evident. First, PRC2 is stably recruited by the actions of JARID2 and MTF2 to a limited number of spatially interacting "nucleation sites," creating H3K27me3-forming Polycomb foci within the nucleus. Second, PRC2 is allosterically activated via its binding to H3K27me3 and rapidly spreads H3K27me2/3 both in cis and in far-cis via long-range contacts. As PRC2 proceeds further from the nucleation sites, its stability on chromatin decreases such that domains of H3K27me3 remain proximal, and those of H3K27me2 distal, to the nucleation sites. This study demonstrates the principles of de novo establishment of PRC2-mediated repressive domains across the genome.
Subject(s)
Polycomb Repressive Complex 2/metabolism , Polycomb-Group Proteins/metabolism , Animals , Chromatin/metabolism , Gene Silencing , Histone Code , Histones/metabolism , Lysine/metabolism , Methylation , Mice , Mice, Inbred C57BL , Mouse Embryonic Stem Cells , Protein Binding , Protein Processing, Post-TranslationalABSTRACT
BACKGROUND AND AIM: In relation to the new umbrella terminology for steatotic liver disease (SLD), we aimed to elucidate the prevalence, distribution, and clinical characteristics of the SLD subgroups in the primary care setting. APPROACH AND RESULTS: We retrospectively collected data from 2535 individuals who underwent magnetic resonance elastography and MRI proton density fat fraction during health checkups in 5 primary care health promotion clinics. We evaluated the presence of cardiometabolic risk factors according to predefined criteria and divided all the participants according to the new SLD classification. The prevalence of SLD was 39.13% in the total cohort, and 95.77% of the SLD cases had metabolic dysfunction (one or more cardiometabolic risk factors). The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) was 29.51%, with those of metabolic dysfunction and alcohol associated steatotic liver disease (MetALD) and alcohol-associated liver disease (ALD) at 7.89% and 0.39%, respectively. According to the old criteria, the prevalence of NAFLD was 29.11%, and 95.80% of the NAFLD cases fulfilled the new criteria for MASLD. The distribution of SLD subtypes was highest for MASLD, at 75.40%, followed by MetALD at 20.06%, cryptogenic SLD at 3.33%, and ALD at 1.01%. The MetALD group had a significantly higher mean magnetic resonance elastography than the MASLD or ALD group. CONCLUSION: Almost all the patients with NAFLD met the new criteria for MASLD. The fibrosis burden of the MetALD group was higher than those of the MASLD and ALD groups.
Subject(s)
Fatty Liver , Liver Cirrhosis , Primary Health Care , Humans , Male , Female , Middle Aged , Prevalence , Retrospective Studies , Liver Cirrhosis/epidemiology , Liver Cirrhosis/pathology , Adult , Fatty Liver/epidemiology , Fatty Liver/pathology , Fatty Liver/diagnostic imaging , Magnetic Resonance Imaging , Non-alcoholic Fatty Liver Disease/epidemiology , Non-alcoholic Fatty Liver Disease/pathology , Non-alcoholic Fatty Liver Disease/diagnostic imaging , Aged , Elasticity Imaging TechniquesABSTRACT
S-acylation, also known as palmitoylation, is the most abundant form of protein lipidation in humans. This reversible posttranslational modification, which targets thousands of proteins, is catalyzed by 23 members of the DHHC family of integral membrane enzymes. DHHC enzymes use fatty acyl-CoA as the ubiquitous fatty acyl donor and become autoacylated at a catalytic cysteine; this intermediate subsequently transfers the fatty acyl group to a cysteine in the target protein. Protein S-acylation intersects with almost all areas of human physiology, and several DHHC enzymes are considered as possible therapeutic targets against diseases such as cancer. These efforts would greatly benefit from a detailed understanding of the molecular basis for this crucial enzymatic reaction. Here, we combine X-ray crystallography with all-atom molecular dynamics simulations to elucidate the structure of the precatalytic complex of human DHHC20 in complex with palmitoyl CoA. The resulting structure reveals that the fatty acyl chain inserts into a hydrophobic pocket within the transmembrane spanning region of the protein, whereas the CoA headgroup is recognized by the cytosolic domain through polar and ionic interactions. Biochemical experiments corroborate the predictions from our structural model. We show, using both computational and experimental analyses, that palmitoyl CoA acts as a bivalent ligand where the interaction of the DHHC enzyme with both the fatty acyl chain and the CoA headgroup is important for catalytic chemistry to proceed. This bivalency explains how, in the presence of high concentrations of free CoA under physiological conditions, DHHC enzymes can efficiently use palmitoyl CoA as a substrate for autoacylation.
Subject(s)
Acyl Coenzyme A/chemistry , Acyl Coenzyme A/metabolism , Acyltransferases/metabolism , Acyltransferases/genetics , Catalytic Domain , Cell Membrane/enzymology , Gene Expression Regulation, Enzymologic , Humans , Lipoylation , Models, Molecular , Molecular Dynamics Simulation , Mutation , Protein Binding , Protein Conformation , Protein DomainsABSTRACT
NANOG protein levels correlate with stem cell pluripotency. NANOG concentrations fluctuate constantly with low NANOG levels leading to spontaneous cell differentiation. Previous literature implicated Pin1, a phosphorylation-dependent prolyl isomerase, as a key player in NANOG stabilization. Here, using NMR spectroscopy, we investigate the molecular interactions of Pin1 with the NANOG unstructured N-terminal domain that contains a PEST sequence with two phosphorylation sites. Phosphorylation of NANOG PEST peptides increases affinity to Pin1. By systematically increasing the amount of cis PEST conformers, we show that the peptides bind tighter to the prolyl isomerase domain (PPIase) of Pin1. Phosphorylation and cis Pro enhancement at both PEST sites lead to a 5-10-fold increase in NANOG binding to the Pin1 WW domain and PPIase domain, respectively. The cis-populated NANOG PEST peptides can be potential inhibitors for disrupting Pin1-dependent NANOG stabilization in cancer stem cells.
Subject(s)
NIMA-Interacting Peptidylprolyl Isomerase , Nanog Homeobox Protein , NIMA-Interacting Peptidylprolyl Isomerase/metabolism , NIMA-Interacting Peptidylprolyl Isomerase/chemistry , NIMA-Interacting Peptidylprolyl Isomerase/genetics , Nanog Homeobox Protein/metabolism , Nanog Homeobox Protein/genetics , Phosphorylation , Humans , Protein Stability , Protein Binding , StereoisomerismABSTRACT
We report the observation of superconductivity in (Pt0.2Ir0.8)3Zr5 with a chiral space group (P6122) at low temperatures. The bulk nature of the superconductivity at a transition temperature of 2.2 K was confirmed using specific heat measurements. We revealed that (Pt0.2Ir0.8)3Zr5 obeys the weak-coupling Bardeen-Cooper-Schrieffer model, and the dominant mechanism in the upper critical field is the orbital pair-breaking limit rather than the Pauli-Clogston limit. This indicates that the antisymmetric spin-orbit coupling caused by the chiral crystal structure does not significantly affect the superconductivity of (Pt0.2Ir0.8)3Zr5.
ABSTRACT
BACKGROUND: We investigated the role of tumor cell-intrinsic PD-L1 signaling in the epithelial-mesenchymal transition (EMT) in non-small-cell lung cancer (NSCLC) and the role of EMT as a predictive biomarker for immune checkpoint inhibitor (ICI) therapy. METHODS: PD-L1-overexpressing or PD-L1-knockdown NSCLC cells underwent RNA-seq and EMT phenotype assessment. Mouse lung cancer LLC cells were injected into nude mice. Two cohorts of patients with NSCLC undergoing ICI therapy were analyzed. RESULTS: RNA-seq showed that EMT pathways were enriched in PD-L1-high NSCLC cells. EMT was enhanced by PD-L1 in NSCLC cells, which was mediated by transforming growth factor-ß (TGFß). PD-L1 promoted the activation of p38-MAPK by binding to and inhibiting the protein phosphatase PPM1B, thereby increasing the TGFß production. Tumor growth and metastasis increased in nude mice injected with PD-L1-overexpressing LLC cells. In the ICI cohort, EMT signature was higher in patients with progressive disease than in those with responses, and EMT was significantly associated with poor survival in PD-L1-high NSCLC. In PD-L1-high NSCLC, EMT was associated with increased M2-macrophage and regulatory T-cell infiltrations and decreased cytotoxic T-cell infiltration. CONCLUSIONS: Tumor cell-intrinsic PD-L1 function contributes to NSCLC progression by promoting EMT. EMT may predict an unfavorable outcome after ICI therapy in PD-L1-high NSCLC.
Subject(s)
B7-H1 Antigen , Carcinoma, Non-Small-Cell Lung , Epithelial-Mesenchymal Transition , Immune Checkpoint Inhibitors , Lung Neoplasms , Mice, Nude , Signal Transduction , Humans , Immune Checkpoint Inhibitors/pharmacology , Immune Checkpoint Inhibitors/therapeutic use , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Lung Neoplasms/immunology , Animals , B7-H1 Antigen/metabolism , B7-H1 Antigen/genetics , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/immunology , Mice , Cell Line, Tumor , Transforming Growth Factor beta/metabolism , FemaleABSTRACT
BACKGROUND & AIMS: Oral antiviral therapy with nucleos(t)ide analogues (NAs) for chronic hepatitis B (CHB) is well-tolerated and lifesaving, but real-world data on utilization are limited. We examined rates of evaluation and treatment in patients from the REAL-B consortium. METHODS: This was a cross-sectional study nested within our retrospective multinational clinical consortium (2000-2021). We determined the proportions of patients receiving adequate evaluation, meeting AASLD treatment criteria, and initiating treatment at any time during the study period. We also identified factors associated with receiving adequate evaluation and treatment using multivariable logistic regression analyses. RESULTS: We analyzed 12,566 adult treatment-naïve patients with CHB from 25 centers in 9 countries (mean age 47.1 years, 41.7% female, 96.1% Asian, 49.6% Western region, 8.7% cirrhosis). Overall, 73.3% (9,206 patients) received adequate evaluation. Among the adequately evaluated, 32.6% (3,001 patients) were treatment eligible by AASLD criteria, 83.3% (2,500 patients) of whom were initiated on NAs, with consistent findings in analyses using EASL criteria. On multivariable logistic regression adjusting for age, sex, cirrhosis, and ethnicity plus region, female sex was associated with adequate evaluation (adjusted odds ratio [aOR] 1.13, p = 0.004), but female treatment-eligible patients were about 50% less likely to initiate NAs (aOR 0.54, p <0.001). Additionally, the lowest evaluation and treatment rates were among Asian patients from the West, but no difference was observed between non-Asian patients and Asian patients from the East. Asian patients from the West (vs. East) were about 40-50% less likely to undergo adequate evaluation (aOR 0.60) and initiate NAs (aOR 0.54) (both p <0.001). CONCLUSIONS: Evaluation and treatment rates were suboptimal for patients with CHB in both the East and West, with significant sex and ethnic disparities. Improved linkage to care with linguistically competent and culturally sensitive approaches is needed. IMPACT AND IMPLICATIONS: Significant sex and ethnic disparities exist in hepatitis B evaluation and treatment, with female treatment-eligible patients about 50% less likely to receive antiviral treatment and Asian patients from Western regions also about 50% less likely to receive adequate evaluation or treatment compared to Asians from the East (there was no significant difference between Asian patients from the East and non-Asian patients). Improved linkage to care with linguistically competent and culturally sensitive approaches is needed.
Subject(s)
Antiviral Agents , Healthcare Disparities , Hepatitis B, Chronic , Humans , Female , Male , Antiviral Agents/therapeutic use , Cross-Sectional Studies , Middle Aged , Retrospective Studies , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/ethnology , Adult , Healthcare Disparities/statistics & numerical data , Healthcare Disparities/ethnology , Sex Factors , Ethnicity/statistics & numerical data , Global HealthABSTRACT
NF-κB essential modulator (NEMO) is a key regulatory protein that functions during NF-κB- and interferon-mediated signaling in response to extracellular stimuli and pathogen infections. Tight regulation of NEMO is essential for host innate immune responses and for maintenance of homeostasis. Here, we report that the E3 ligase MARCH2 is a novel negative regulator of NEMO-mediated signaling upon bacterial or viral infection. MARCH2 interacted directly with NEMO during the late phase of infection and catalyzed K-48-linked ubiquitination of Lys326 on NEMO, which resulted in its degradation. Deletion of MARCH2 resulted in marked resistance to bacterial/viral infection, along with increased innate immune responses both in vitro and in vivo. In addition, MARCH2-/- mice were more susceptible to LPS challenge due to massive production of cytokines. Taken together, these findings provide new insight into the molecular regulation of NEMO and suggest an important role for MARCH2 in homeostatic control of innate immune responses.
Subject(s)
Intracellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/metabolism , Ubiquitin-Protein Ligases/metabolism , Ubiquitins/metabolism , Animals , Cell Line , Female , Gene Deletion , Humans , Immunity, Innate/physiology , Intracellular Signaling Peptides and Proteins/genetics , Membrane Proteins/deficiency , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Inbred ICR , Mice, Knockout , NF-kappa B/metabolism , Signal Transduction/genetics , Transcriptome , Ubiquitin-Protein Ligases/genetics , UbiquitinationABSTRACT
The orphan nuclear receptor estrogen-related receptor α (ERRα; NR3B1) is a key metabolic regulator, but its function in regulating inflammation remains largely unknown. Here, we demonstrate that ERRα negatively regulates Toll-like receptor (TLR)-induced inflammation by promoting Tnfaip3 transcription and fine-tuning of metabolic reprogramming in macrophages. ERRα-deficient (Esrra(-/-)) mice showed increased susceptibility to endotoxin-induced septic shock, leading to more severe pro-inflammatory responses than control mice. ERRα regulated macrophage inflammatory responses by directly binding the promoter region of Tnfaip3, a deubiquitinating enzyme in TLR signaling. In addition, Esrra(-/-) macrophages showed an increased glycolysis, but impaired mitochondrial respiratory function and biogenesis. Further, ERRα was required for the regulation of NF-κB signaling by controlling p65 acetylation via maintenance of NAD(+) levels and sirtuin 1 activation. These findings unravel a previously unappreciated role for ERRα as a negative regulator of TLR-induced inflammatory responses through inducing Tnfaip3 transcription and controlling the metabolic reprogramming.
Subject(s)
Cysteine Endopeptidases/biosynthesis , Inflammation/immunology , Intracellular Signaling Peptides and Proteins/biosynthesis , Macrophages/metabolism , Receptors, Estrogen/genetics , Toll-Like Receptor 4/immunology , Acetylation , Animals , Calcium/metabolism , Calcium-Calmodulin-Dependent Protein Kinase Kinase/metabolism , Cells, Cultured , Cysteine Endopeptidases/genetics , Enzyme Activation/genetics , Glycolysis/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Lipopolysaccharides , Macrophages/immunology , Mice , Mice, Knockout , Myeloid Differentiation Factor 88/metabolism , NAD/metabolism , Oxidative Phosphorylation , Promoter Regions, Genetic/genetics , Promoter Regions, Genetic/immunology , Shock, Septic/immunology , Signal Transduction , Sirtuin 1/metabolism , TNF Receptor-Associated Factor 6/metabolism , Transcription Factor RelA/metabolism , Transcription, Genetic/genetics , Tumor Necrosis Factor alpha-Induced Protein 3 , Ubiquitination , ERRalpha Estrogen-Related ReceptorABSTRACT
The triple bond in N2 is significantly stronger than the double bond in O2, meaning that synthesizing nitrogen-rich nitrides typically requires activated nitrogen precursors, such as ammonia, plasma-cracked atomic nitrogen, or high-pressure N2. Here, we report a synthesis of nitrogen-rich nitrides under ambient pressure and atmosphere. Using Na2MoO4 and dicyandiamide precursors, we synthesized nitrogen-rich γ-Mo2N3 in an alumina crucible under an ambient atmosphere, heated in a box furnace between 500 and 600 °C. Byproducts of this metathesis reaction include volatile gases and solid Na(OCN), which can be washed away with water. X-ray diffraction and neutron diffraction showed Mo2N3 with a rock salt structure having cation vacancies, with no oxygen incorporation, in contrast to the more common nitrogen-poor rock salt Mo2N with anion vacancies. Moreover, an increase in temperature to 700 °C resulted in molybdenum oxynitride, Mo0.84N0.72O0.27. This work illustrates the potential for dicyandiamide as an ambient-temperature metathesis precursor for an increased effective nitrogen chemical potential under ambient conditions. The classical experimental setting often used for solid-state oxide synthesis, therefore, has the potential to expand the nitride chemistry.
ABSTRACT
Four new compounds, racemic chalcone-monoterpene hybrids (1-3) and a chalcone (9), along with nine known compounds (4-8, 10-13), have been isolated from the buds of Cleistocalyx operculatus. The chemical structures of the isolated compounds were identified through NMR data analysis and confirmed by computational methods, including electronic circular dichroism (ECD) calculations, and further synthetic approaches. Compounds 1-5 were synthesized via a Diels-Alder reaction, a process informed by biomimetic condensation studies that combined chalcones and monoterpenes. These synthetic approaches also yielded various unnatural chalcone-monoterpene derivatives (14-23). The inhibitory effects on protein tyrosine phosphatase 1B (PTP1B) of both naturally isolated and synthetically obtained compounds were evaluated. Compounds 4, 9, 13, and 16b exhibited potent PTP1B inhibitory activity, with IC50 values ranging from 0.9 ± 0.2 to 3.9 ± 0.7 µM. The enantiomers (+)-4 and (-)-16b showed enhanced activity compared to their respective enantiomers. Kinetic studies indicate that all active compounds inhibit PTP1B through mixed mechanisms, and molecular docking simulations agree with the experimental assays on PTP1B. Our results suggest that chalcone-meroterpene adducts from the buds of C. operculatus exhibit potential as antidiabetic agents, partly due to their PTP1B enzyme inhibition.