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1.
Hum Mol Genet ; 32(22): 3123-3134, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37166351

RESUMO

Germline pathogenic variants in two genes encoding the lysine-specific histone methyltransferase genes SETD1A and SETD2 are associated with neurodevelopmental disorders (NDDs) characterized by developmental delay and congenital anomalies. The SETD1A and SETD2 gene products play a critical role in chromatin-mediated regulation of gene expression. Specific methylation episignatures have been detected for a range of chromatin gene-related NDDs and have impacted clinical practice by improving the interpretation of variant pathogenicity. To investigate if SETD1A and/or SETD2-related NDDs are associated with a detectable episignature, we undertook targeted genome-wide methylation profiling of > 2 M CpGs using a next-generation sequencing-based assay. A comparison of methylation profiles in patients with SETD1A variants (n = 6) did not reveal evidence of a strong methylation episignature. A review of the clinical and genetic features of the SETD2 patient group revealed that, as reported previously, there were phenotypic differences between patients with truncating mutations (n = 4, Luscan-Lumish syndrome; MIM:616831) and those with missense codon 1740 variants [p.Arg1740Trp (n = 4) and p.Arg1740Gln (n = 2)]. Both SETD2 subgroups demonstrated a methylation episignature, which was characterized by hypomethylation and hypermethylation events, respectively. Within the codon 1740 subgroup, both the methylation changes and clinical phenotype were more severe in those with p.Arg1740Trp variants. We also noted that two of 10 cases with a SETD2-NDD had developed a neoplasm. These findings reveal novel epigenotype-genotype-phenotype correlations in SETD2-NDDs and predict a gain-of-function mechanism for SETD2 codon 1740 pathogenic variants.


Assuntos
Cromatina , Transtornos do Neurodesenvolvimento , Humanos , Cromatina/genética , Metilação de DNA/genética , Mutação , Transtornos do Neurodesenvolvimento/genética , Estudos de Associação Genética , Códon
2.
Plant Physiol ; 194(4): 2755-2770, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38235781

RESUMO

Apple Valsa canker (AVC) is a devastating disease of apple (Malus × domestica), caused by Valsa mali (Vm). The Cysteine-rich secretory protein, Antigen 5, and Pathogenesis-related protein 1 (CAP) superfamily protein PATHOGENESIS-RELATED PROTEIN 1-LIKE PROTEIN c (VmPR1c) plays an important role in the pathogenicity of Vm. However, the mechanisms through which it exerts its virulence function in Vm-apple interactions remain unclear. In this study, we identified an apple valine-glutamine (VQ)-motif-containing protein, MdVQ29, as a VmPR1c target protein. MdVQ29-overexpressing transgenic apple plants showed substantially enhanced AVC resistance as compared with the wild type. MdVQ29 interacted with the transcription factor MdWRKY23, which was further shown to bind to the promoter of the jasmonic acid (JA) signaling-related gene CORONATINE INSENSITIVE 1 (MdCOI1) and activate its expression to activate the JA signaling pathway. Disease evaluation in lesion areas on infected leaves showed that MdVQ29 positively modulated apple resistance in a MdWRKY23-dependent manner. Furthermore, MdVQ29 promoted the transcriptional activity of MdWRKY23 toward MdCOI1. In addition, VmPR1c suppressed the MdVQ29-enhanced transcriptional activation activity of MdWRKY23 by promoting the degradation of MdVQ29 and inhibiting MdVQ29 expression and the MdVQ29-MdWRKY23 interaction, thereby interfering with the JA signaling pathway and facilitating Vm infection. Overall, our results demonstrate that VmPR1c targets MdVQ29 to manipulate the JA signaling pathway to regulate immunity. Thus, this study provides an important theoretical basis and guidance for mining and utilizing disease-resistance genetic resources for genetically improving apples.


Assuntos
Ascomicetos , Ciclopentanos , Malus , Oxilipinas , Malus/genética , Malus/metabolismo , Glutamina/metabolismo , Valina/metabolismo , Transdução de Sinais , Doenças das Plantas/genética
3.
J Biol Chem ; 299(3): 102918, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36657642

RESUMO

Multiple proteins bind to telomeric DNA and are important for the role of telomeres in genome stability. A recent study established a broad-complex, tramtrack and bric-à-brac - zinc finger (BTB-ZF) protein, ZBTB10 (zinc finger and BTB domain-containing protein 10), as a telomeric variant repeat-binding protein at telomeres that use an alternative method for lengthening telomeres). ZBTB10 specifically interacts with the double-stranded telomeric variant repeat sequence TTGGGG by employing its tandem C2H2 zinc fingers (ZF1-2). Here, we solved the crystal structure of human ZBTB10 ZF1-2 in complex with a double-stranded DNA duplex containing the sequence TTGGGG to assess the molecular details of this interaction. Combined with calorimetric analysis, we identified the vital residues in TTGGGG recognition and determined the specific recognition mechanisms that are different from those of TZAP (telomere zinc finger-associated protein), a recently defined telomeric DNA-binding protein. Following these studies, we further identified a single amino-acid mutant (Arg767Gln) of ZBTB10 ZF1-2 that shows a preference for the telomeric DNA repeat TTAGGG sequence. We solved the cocrystal structure, providing a structural basis for telomeric DNA recognition by C2H2 ZF proteins.


Assuntos
Proteínas de Ligação a DNA , Proteínas Repressoras , Humanos , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ligação Proteica , Proteínas Repressoras/metabolismo , Telômero/metabolismo , Dedos de Zinco/genética
4.
J Biol Chem ; 299(2): 102903, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36642179

RESUMO

Members of glycosyltransferase family 75 (GT75) not only reversibly catalyze the autoglycosylation of a conserved arginine residue with specific NDP-sugars but also exhibit NDP-pyranose mutase activity that reversibly converts specific NDP-pyranose to NDP-furanose. The latter activity provides valuable NDP-furanosyl donors for glycosyltransferases and requires a divalent cation as a cofactor instead of FAD used by UDP-D-galactopyranose mutase. However, details of the mechanism for NDP-pyranose mutase activity are not clear. Here we report the first crystal structures of GT75 family NDP-pyranose mutases. The novel structures of GT75 member MtdL in complex with Mn2+ and GDP, GDP-D-glucopyranose, GDP-L-fucopyranose, GDP-L-fucofuranose, respectively, combined with site-directed mutagenesis studies, reveal key residues involved in Mn2+ coordination, substrate binding, and catalytic reactions. We also provide a possible catalytic mechanism for this unique type of NDP-pyranose mutase. Taken together, our results highlight key elements of an enzyme family important for furanose biosynthesis.


Assuntos
Actinobacteria , Glicosiltransferases , Transferases Intramoleculares , Galactose/metabolismo , Glicosiltransferases/química , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Transferases Intramoleculares/química , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Mutagênese Sítio-Dirigida , Actinobacteria/enzimologia
5.
Mol Plant Microbe Interact ; 37(6): 520-529, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38470518

RESUMO

E3 ubiquitin ligases play a critical role in plant disease resistance. Among them, the Skp1-Cullin-F-box protein (SCF) ubiquitin ligase complex is the largest family and regulates the ubiquitination of a wide range of proteins. Apple Valsa canker (AVC) is a fungal disease of apple trees caused by the fungus Valsa mali, which can lead to significant economic losses. However, the function of the SCF complex in apple resistance to this disease is still largely unknown. In this study, we identified an SCF ubiquitin ligase complex that can enhance resistance to Valsa canker in apple. Disease evaluation experiments demonstrated that MdSkp1 increased apple resistance to AVC. Furthermore, MdSkp1 interacted with an F-box protein, MdSKIP14, and interacted with a cullin-1 protein, MdCUL1, to form an SCF ubiquitin ligase complex. Additionally, we revealed both MdSKIP14 and MdCUL1 as positive regulators of AVC resistance. In conclusion, our results identified an SCF complex capable of contributing to apple resistance against AVC, providing a theoretical basis for apple disease resistance and the sustainable development of the industry. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Ascomicetos , Resistência à Doença , Malus , Doenças das Plantas , Proteínas de Plantas , Proteínas Ligases SKP Culina F-Box , Malus/microbiologia , Malus/genética , Malus/imunologia , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Resistência à Doença/genética , Proteínas Ligases SKP Culina F-Box/metabolismo , Proteínas Ligases SKP Culina F-Box/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ascomicetos/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Plantas Geneticamente Modificadas
6.
Biochem Biophys Res Commun ; 721: 150122, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38776834

RESUMO

Let-7 was one of the first microRNAs (miRNAs) to be discovered and its expression promotes differentiation during development and function as tumor suppressors in various cancers. The maturation process of let-7 miRNA is tightly regulated by multiple RNA-binding proteins. For example, LIN28 binds to the terminal loops of the precursors of let-7 family and block their processing into mature miRNAs. Trim25 promotes the uridylation-mediated degradation of pre-let-7 modified by LIN28/TUT4. Recently, human pseudouridine synthase TruB1 has been reported to facilitate let-7 maturation by directly binding to pri-let-7 and recruiting Drosha-DGCR8 microprocessor. Through biochemical assay and structural investigation, we show that human TruB1 binds specifically the terminal loop of pri-let-7a1 at nucleotides 31-41, which folds as a small stem-loop architecture. Although TruB1 recognizes the terminal loop of pri-let-7a1 in a way similar to how E. coli TruB interacts with tRNA, a conserved KRKK motif in human and other higher eukaryotes adds an extra binding interface and strengthens the recognition of TruB1 for pri-let-7a1 through electrostatic interactions. These findings reveal the structural basis of TruB1-pri-let-7 interaction which may assists the elucidation of precise role of TruB1 in biogenesis of let-7.


Assuntos
MicroRNAs , Humanos , MicroRNAs/metabolismo , MicroRNAs/genética , Ligação Proteica , Modelos Moleculares , Transferases Intramoleculares/metabolismo , Transferases Intramoleculares/química , Transferases Intramoleculares/genética , Conformação de Ácido Nucleico , Sítios de Ligação , Sequência de Aminoácidos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética
7.
Anal Bioanal Chem ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441613

RESUMO

The development of novel catalyst with high catalytic activity is important for electrochemical non-enzymatic glucose sensing. Here, iridium single-atom/nickel oxide nanoparticle/N-doped graphene nanosheet (Ir1/NiO/NG) with the loading of 1.13 wt% Ir was successfully synthesized for constructing electrochemical non-enzymatic glucose sensor for the first time. The morphology and structure of Ir1/NiO/NG were characterized by XRD, SEM, TEM, HRTEM, and XPS, and the presence of Ir SAs was confirmed by AC-HAADF-STEM. The Ir1/NiO/NG shows 65 mV lower oxidation potential and 3.3 times higher response current than Ni(OH)2/NG. In addition, Ir1/NiO/NG exhibits high sensitivity (70.09 µA mM-1 cm-2), excellent selectivity, low detection limit (2.00 µM), and great stability (91.53% current remaining after 21 days) for electrochemical non-enzymatic glucose sensing. The outstanding catalytic and sensing performance of Ir1/NiO/NG is mainly attributed to synergistic effect of Ir SAs, NiO nanoparticles, and highly conductive NG, which modulate the electronic and geometric structure of Ir1/NiO/NG. This work shows the promising potential of SACs in electrochemical sensing.

8.
J Gastroenterol Hepatol ; 39(3): 544-551, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38059883

RESUMO

BACKGROUND AND AIM: Chromoendoscopy with the use of indigo carmine (IC) dye is a crucial endoscopic technique to identify gastrointestinal neoplasms. However, its performance is limited by the endoscopist's skill, and no standards are available for lesion identification. Thus, we developed an artificial intelligence (AI) model to replace chromoendoscopy. METHODS: This pilot study assessed the feasibility of our novel AI model in the conversion of white-light images (WLI) into virtual IC-dyed images based on a generative adversarial network. The predictions of our AI model were evaluated against the assessments of five endoscopic experts who were blinded to the purpose of this study with a staining quality rating from 1 (unacceptable) to 4 (excellent). RESULTS: The AI model successfully transformed the WLI of polyps with different morphologies and different types of lesions in the gastrointestinal tract into virtual IC-dyed images. The quality ratings of the real IC-dyed and AI images did not significantly differ concerning surface structure (AI vs IC: 3.08 vs 3.00), lesion border (3.04 vs 2.98), and overall contrast (3.14 vs 3.02) from 10 sets of images (10 AI images and 10 real IC-dyed images). Although the score depended significantly on the evaluator, the staining methods (AI or real IC) and evaluators had no significant interaction (P > 0.05) with each other. CONCLUSION: Our results demonstrated the feasibility of employing AI model's virtual IC staining, increasing the possibility of being employed in daily practice. This novel technology may facilitate gastrointestinal lesion identification in the future.


Assuntos
Inteligência Artificial , Lesões Pré-Cancerosas , Humanos , Projetos Piloto , Endoscopia/métodos , Índigo Carmim , Carmim , Lesões Pré-Cancerosas/diagnóstico por imagem
9.
BMC Geriatr ; 24(1): 523, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886643

RESUMO

PURPOSE: Smoking is a risk factor for sarcopenia. Nevertheless, few studies analyzed the independent effects of various smoking dimensions (duration, intensity, cumulative dose) on sarcopenia risk. This is a cross-sectional study based on an older population in Zhejiang Province to determine which smoking dimensions are mainly important for sarcopenia risk and to explore the dose-response relationship between them. METHODS: Our study included 783 patients with sarcopenia and 4918 non-sarcopenic individuals. Logistic regression and restricted cubic with logistic regression (for nonlinear dose effects) were used to obtain odds ratios (ORs) and 95% confidence intervals as well as restricted cubic splines (RCS) curves. RESULTS: Compared with never-smokers, current smokers had an increased risk of sarcopenia (OR = 1.786; 95% CI 1.387-2.301) after adjusting for confounders such as age, sex, education, alcohol consumption, disease history, etc. There was no significant association between smoking intensity and sarcopenia after more than 20 cigarettes per day (OR = 1.484; 95% CI 0.886-2.487), whereas the risk of sarcopenia increased significantly with increasing duration of smoking after more than 40 years (OR = 1.733; 95% CI 1.214-2.473). Meanwhile, there was a significant non-linear dose-response relationship between smoking duration or intensity and the risk of sarcopenia. However, the risk of sarcopenia increased linearly with the number of pack-years of smoking, which is not a significant nonlinear dose-response relationship. CONCLUSIONS: This study indicated the association between smoking and sarcopenia. Both smoking duration and cumulative dose were significantly and positively associated with sarcopenia. These findings reflect the important role of the number of years of smoking in increasing the risk of sarcopenia and provide scientific evidence that different smoking dimensions may influence the risk of the sarcopenia.


Assuntos
Fumar Cigarros , Sarcopenia , Humanos , Sarcopenia/epidemiologia , Estudos Transversais , Masculino , Feminino , Idoso , China/epidemiologia , Fumar Cigarros/epidemiologia , Fumar Cigarros/efeitos adversos , Pessoa de Meia-Idade , Fatores de Risco , Idoso de 80 Anos ou mais
10.
Nucleic Acids Res ; 50(18): 10614-10625, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36177876

RESUMO

In Arabidopsis, HESO1 and URT1 act cooperatively on unmethylated miRNA and mRNA uridylation to induce their degradation. Their collaboration significantly impacts RNA metabolism in plants. However, the molecular mechanism determining the functional difference and complementarity of these two enzymes remains unclear. We previously solved the three-dimensional structure of URT1 in the absence and presence of UTP. In this study, we further determined the structure of URT1 in complex with a 5'-AAAU-3' RNA stretch that mimics the post-catalytic state of the mRNA poly(A) tail after the addition of the first uridine. Structural analysis and enzymatic assays revealed that L527 and Y592 endow URT1 with a preference to interact with purine over pyrimidine at the -1 RNA binding position, thus controlling the optimal number of uridine added to the 3' extremity of poly(A) as two. In addition, we observed that a large-scale conformational rearrangement in URT1 occurs upon binding with RNA from an 'open' to a 'closed' state. Molecular dynamic simulation supports an open-closed conformational selection mechanism employed by URT1 to interact with RNA substrates and maintain distributive enzymatic activity. Based on the above results, a model regarding the catalytic cycle of URT1 is proposed to explain its di-uridylation activity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , RNA Nucleotidiltransferases/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Purinas/metabolismo , RNA Mensageiro/metabolismo , Uridina Trifosfato/metabolismo
11.
Funct Integr Genomics ; 23(3): 232, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37432513

RESUMO

TRIP13 is highly expressed in various human tumors and promotes tumorigenesis. We aimed to explore the biological effect of TRIP13 on gastric cancer. The RNA sequence data were retrieved from TCGA to evaluate TRIP13 mRNA expression in gastric cancer. Paired formalin-fixed paraffin-embedded blocks were further analyzed to verify the relationship between TRIP13 expression and carcinogenic status. The functions of TRIP13 on the proliferation of gastric malignancy were investigated by MTT, flow cytometry, colony formation experiment, and nude mouse tumor formation experiment. Finally, microarray analysis of TRIP13-related pathways was performed to identify the potential underlying mechanism of TRIP13 in gastric cancer. TRIP13 was found to have high expression in tumor samples. TRIP13 expression status was significantly subjective to tumor-node-metastasis (TNM) staging and poor survival. The downregulation of TRIP13 promoted apoptosis and inhibited tumor growth. TRIP13-dependent JAK/STAT and NF-κB signaling cascade were found as two key pathways in the carcinogenesis of GC. In conclusion, TRIP13 participates in the carcinogenesis of stomach cancer, and its overexpression in the cancerous tissues dovetail with advanced stage and survival. Moreover, TRIP13 functions as an upstream regulator of the JAK/STAT and p53 signaling pathways, which play critical roles in developing various malignancies.


Assuntos
Neoplasias Gástricas , Humanos , Animais , Camundongos , Neoplasias Gástricas/genética , Carcinogênese/genética , Regulação para Baixo , Apoptose , NF-kappa B , ATPases Associadas a Diversas Atividades Celulares , Proteínas de Ciclo Celular
12.
Clin Gastroenterol Hepatol ; 21(2): 337-346.e3, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35863686

RESUMO

BACKGROUND AND AIMS: Artificial intelligence (AI)-assisted colonoscopy improves polyp detection and characterization in colonoscopy. However, data from large-scale multicenter randomized controlled trials (RCT) in an asymptomatic population are lacking. METHODS: This multicenter RCT aimed to compare AI-assisted colonoscopy with conventional colonoscopy for adenoma detection in an asymptomatic population. Asymptomatic subjects 45-75 years of age undergoing colorectal cancer screening by direct colonoscopy or fecal immunochemical test were recruited in 6 referral centers in Hong Kong, Jilin, Inner Mongolia, Xiamen, and Beijing. In the AI-assisted colonoscopy, an AI polyp detection system (Eagle-Eye) with real-time notification on the same monitor of the endoscopy system was used. The primary outcome was overall adenoma detection rate (ADR). Secondary outcomes were mean number of adenomas per colonoscopy, ADR according to endoscopist's experience, and colonoscopy withdrawal time. This study received Institutional Review Board approval (CRE-2019.393). RESULTS: From November 2019 to August 2021, 3059 subjects were randomized to AI-assisted colonoscopy (n = 1519) and conventional colonoscopy (n = 1540). Baseline characteristics and bowel preparation quality between the 2 groups were similar. The overall ADR (39.9% vs 32.4%; P < .001), advanced ADR (6.6% vs 4.9%; P = .041), ADR of expert (42.3% vs 32.8%; P < .001) and nonexpert endoscopists (37.5% vs 32.1%; P = .023), and adenomas per colonoscopy (0.59 ± 0.97 vs 0.45 ± 0.81; P < .001) were all significantly higher in the AI-assisted colonoscopy. The median withdrawal time (8.3 minutes vs 7.8 minutes; P = .004) was slightly longer in the AI-assisted colonoscopy group. CONCLUSIONS: In this multicenter RCT in asymptomatic patients, AI-assisted colonoscopy improved overall ADR, advanced ADR, and ADR of both expert and nonexpert attending endoscopists. (ClinicalTrials.gov, Number: NCT04422548).


Assuntos
Adenoma , Pólipos do Colo , Neoplasias Colorretais , Humanos , Detecção Precoce de Câncer , Neoplasias Colorretais/diagnóstico , Colonoscopia , Pólipos do Colo/diagnóstico , Adenoma/diagnóstico , Inteligência Artificial , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
BMC Psychiatry ; 23(1): 44, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650485

RESUMO

BACKGROUND: Accumulating evidence showed that dietary habits might modify the risk of depression. This study aimed to evaluate the longitudinal association of egg consumption with depressive symptoms in the Chinese elderly. METHODS: We analyzed the data from Zhejiang Ageing and Health Cohort Study including 8289 participants. The Patient Health Questionnaire-9 scale (PHQ-9) was used to assess depressive symptoms at baseline and three waves of follow-up (2015, 2016, and 2019-2020). A PHQ-9 cut-off score ≥ 5 was used to define depressive symptoms. The participants with depressive symptoms at baseline were excluded. Egg consumption was evaluated through the diet habits section of the baseline questionnaire. Self-reported egg consumption was measured as the number of eggs per week and categorized into three categories. Log-binomial regression models with Generalized Estimating Equations were utilized to evaluate the association of egg consumption with depressive symptoms and estimate relative risks (RRs). RESULTS: The mean age of included participants was 68.6 years. After 6 years of follow-up, 1385 (16.7%) participants were indicated with depressive symptoms by PHQ-9 at least once. Compared with non-consumers or less-than-weekly consumers, participants consuming < 3 eggs/week and ≥ 3 eggs/week had 30% (RR = 0.70, 95%CI 0.62-0.80) and 38% (RR = 0.62, 95%CI 0.54-0.71) lower risks of depressive symptoms, respectively. A linear association was confirmed (P for trend < 0.01), and each egg increment per week was associated with a 4% lower risk of depressive symptoms (RR = 0.96, 95%CI 0.93-0.99). Sensitivity analyses yielded consistent results to the main analyses. CONCLUSIONS: Egg consumption is prospectively related to a lower risk of depressive symptoms in the Chinese elderly. More prospective studies are needed to verify the association.


Assuntos
Depressão , Humanos , Idoso , Estudos de Coortes , Fatores de Risco , Estudos Prospectivos , Inquéritos e Questionários
14.
Nanotechnology ; 33(13)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34808604

RESUMO

The catalyst of nanoporous Cu (NP-Cu) powders, with the chemical composition of Cu79.63Ni6.85O13.53(at%), was successfully fabricated by dealloying of Zr-Cu-Ni-Al metallic glassy precursors. The as-prepared NP-Cu powders, co-existing with Cu2O phase on Cu ligament surface, had a three-dimensional network porous structure. The NP-Cu powders/H2O2system showed superior catalytic degradation efficiency toward azo dyes in both acidic (pH 2) and neutral (pH 7) environments. Moreover, the cyclic tests indicated that this powder catalyst also exhibited good durability. A novel degradation mechanism of NP-Cu powders/H2O2was proposed: the high degradation performance in acidic environment was mainly derived from heterogeneous reaction involved with a specific pathway related to Cu3+to produce HO·, while in neutral environment it was primarily resulted from homogeneous reaction with the generation of HO· from the classical Cu-based Fenton-like process. This work indicates that the NP-Cu powders have great potential applications as catalysts for wastewater treatments.

15.
Environ Res ; 205: 112318, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742710

RESUMO

Alzheimer's disease (AD) is the most common type of dementia. Impact of air pollution (AP) on the risk of AD is unclear. It is unknown which air pollutants are independently associated with AD and whether fish consumption mitigated the association. We carried out a community-based cohort of 6115 participants aged ≥60 years in China to examine the association of PM2.5, PM10, CO, NO2, SO2 and O3 exposure with AD, and differences in the association between people with low and high consumption of fish. The participants were randomly recruited from six counties in Zhejiang province for health survey to document socio-demographic and disease risk factors in 2014, and were followed up to diagnose AD in 2019. A total of 986 cohort members were diagnosed with AD. Based on the daily mean air pollutants monitored in 2013-2015 in the counties, participants were divided into low, middle and high AP exposure groups for subsequent analysis. The multiple adjusted odds ratio (OR) of AD in participants living with the middle and high levels of PM2.5 exposure versus the low exposure were 1.50 (95% CI 0.90-2.50) and 3.92 (2.09-7.37). The increased ORs were also with PM10 (1.74, 0.65-4.64; 3.00, 1.22-7.41) and CO (2.86, 1.32-6.20; 1.19, 0.45-3.18), but not with NO2 (0.63, 0.17-2.27; 0.95, 0.28-3.19), SO2 (0.44, 0.19-1.001; 1.21, 0.56-2.62), and O3 (0.38, 0.20-0.74; 0.50, 0.21-1.21). There were no significant interaction effects of AP with fish consumption on AD. However, participants with low consumption of fish appeared to have higher ORs in PM2.5 exposure (1.80, 1.39-2.33; 5.18, 3.93-6.82) than those high consumption (1.38, 0.78-2.47; 2.89, 1.50-5.59). Our findings of PM2.5, PM10 and CO exposure significantly increased the risk of AD and the potential mitigating effect of fish consumption on the association provide evidence for developing effective strategies for AD reduction and air pollution control.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Doença de Alzheimer , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/epidemiologia , China/epidemiologia , Estudos de Coortes , Exposição Ambiental/análise , Humanos , Material Particulado/análise , Material Particulado/toxicidade
16.
Phytopathology ; 112(10): 2187-2197, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35509209

RESUMO

Valsa mali is the main pathogenic fungus that causes the apple Valsa canker, a destructive disease severely threatening apple production in the world. However, the underlying key components involved in resistance against V. mali in apple trees remain largely unexplored. Here, we isolated and functionally characterized a G-type lectin S-receptor-like protein kinase MdSRLK3 from the cultivar Royal Gala derivative line GL-3. qRT-PCR showed that the relative expression of MdSRLK3 in apple branches reached its highest level at 24 h post V. mali inoculation, which was 13.42 times higher than without inoculation. Transient overexpression of MdSRLK3 enhanced apple resistance against V. mali, while transient silencing of MdSRLK3 reduced its resistance against the pathogen. More importantly, stable silencing of MdSRLK3 resulted in reduced resistance against this fungus. Furthermore, we demonstrated that MdSRLK3 positively regulated apple resistance by affecting the Ca2+ signaling pathway, and the regulation was also related to the H2O2 and callose signaling pathways. Overall, our data reveal that MdSRLK3 is a positive regulator of apple immunity.


Assuntos
Ascomicetos , Malus , Ascomicetos/metabolismo , Peróxido de Hidrogênio/metabolismo , Lectinas/metabolismo , Malus/genética , Malus/microbiologia , Doenças das Plantas/microbiologia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Transdução de Sinais
17.
Nucleic Acids Res ; 48(19): 11097-11112, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33035348

RESUMO

The microprocessor complex cleaves the primary transcript of microRNA (pri-miRNA) to initiate miRNA maturation. Microprocessor is known to consist of RNase III DROSHA and dsRNA-binding DGCR8. Here, we identify Enhancer of Rudimentary Homolog (ERH) as a new component of Microprocessor. Through a crystal structure and biochemical experiments, we reveal that ERH uses its hydrophobic groove to bind to a conserved region in the N-terminus of DGCR8, in a 2:2 stoichiometry. Knock-down of ERH or deletion of the DGCR8 N-terminus results in a reduced processing of suboptimal pri-miRNAs in polycistronic miRNA clusters. ERH increases the processing of suboptimal pri-miR-451 in a manner dependent on its neighboring pri-miR-144. Thus, the ERH dimer may mediate 'cluster assistance' in which Microprocessor is loaded onto a poor substrate with help from a high-affinity substrate in the same cluster. Our study reveals a role of ERH in the miRNA biogenesis pathway.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Processamento Pós-Transcricional do RNA , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Células HCT116 , Células HEK293 , Humanos , Células K562 , MicroRNAs/metabolismo , Ligação Proteica , Conformação Proteica
18.
Mediators Inflamm ; 2022: 3665934, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36123994

RESUMO

Intervertebral disc degeneration (IVDD) has been a complex disorder resulted from genetic and environmental risk factors. The aim of this study was to identify the risk factors associated with IVDD in orthopaedic patients and develop a prediction model for predicting the risk of IVDD. A total of 309 patients were retrospectively included in the study and randomly divided into the training group and the validation group. The least absolute shrinkage and selection operator regression (LASSO) and the univariate logistic regression analysis were used to optimize factors selection for the IVDD risk model. Multivariable logistic regression analysis was used to establish a predicting nomogram model incorporating the factors. In addition, discrimination, calibration, and clinical usefulness of the nomogram model were evaluated via the C-index, receiver operating characteristic (ROC) curve, calibration plot, and decision curve analysis (DCA). Then, based on the results above, the relationship between IVDD and angiotensin II (AngII) level in peripheral blood was examined prospectively. The predictors of the nomogram include age, sex, hypertension, diabetes, gout, working posture, and exercising hours per week. The C-index values of the training and validation groups were 0.916 (95% CI, 0.876-0.956) and 0.949 (95% CI, 0.909-0.989), respectively, which indicated that the model displayed good discrimination. In addition, the area under the curve (AUC) values of the ROC curve of the training and the validation group were 0.815 (95% CI, 0.759-0.870) and 0.805 (95% CI, 0.718-0.892), respectively, revealing the satisfactory discrimination performance of the model. The prospective investigation showed that the average AngII level in the degenerated group (97.62 ± 44.02 pg/mL) was significantly higher than that in the nondegenerated group (52.91 ± 9.01 pg/mL) (p < 0.001). This present study explored the risk factors for IVDD and established a prediction model, which would effectively predict the risk of IVDD. In addition, based on the prediction model, AngII was revealed to be a potentially auxiliary clinical diagnostic marker for IVDD.


Assuntos
Degeneração do Disco Intervertebral , Nomogramas , Angiotensina II , Humanos , Estudos Prospectivos , Estudos Retrospectivos
19.
Mediators Inflamm ; 2022: 1625290, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757109

RESUMO

Bone homeostasis has been a dynamic equilibrium between osteoclasts (OCs) and osteoblasts (OBs). However, excessive activation of OCs could disturb the bone homeostasis. As a result, effective medical interventions for patients are greatly demanding. NO/guanylate cyclase (GC)/cGMP signaling cascade has been previously reported to regulate bone metabolism, and GC plays a significantly critical role. Vericiguat, as a novel oral soluble guanylate cyclase (sGC) stimulator, has been firstly reported in 2020 to treat patients with heart failure. Nevertheless, the biological effects of Vericiguat on the function of OCs have not yet been explored. In this present study, we found that Vericiguat with the concentration between 0 and 8 µM was noncytotoxic to bone marrow-derived monocyte-macrophage lineage (BMMs). Vericiguat could enhance the differentiation of OCs at concentration of 500 nM, whereas it inhibited OC differentiation at 8 µM. In addition, Vericiguat also showed dual effects on OC fusion and bone resorption in a dose-dependent manner. Furthermore, a molecular assay suggested that the dual regulatory effects of Vericiguat on OCs were mediated by the bidirectional activation of the IκB-α/NF-κB signaling pathway. Taken together, our present study demonstrated the dual effects of Vericiguat on the formation of functional OCs. The regulatory effects of Vericiguat on OCs were achieved by the bidirectional modulation of the IκB-α/NF-κB signaling pathway, and a potential balance between the IκB-α/NF-κB signaling pathway and sGC/cGMP/VASP may exist.


Assuntos
Reabsorção Óssea , Osteoclastos , Reabsorção Óssea/metabolismo , Diferenciação Celular , Compostos Heterocíclicos com 2 Anéis , Humanos , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/metabolismo , Osteoclastos/metabolismo , Pirimidinas , Ligante RANK/metabolismo
20.
Angew Chem Int Ed Engl ; 61(28): e202204290, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35536725

RESUMO

Catalytic selective hydroxylation of unactivated aliphatic (sp3 ) C-H bonds without a directing group represents a formidable task for synthetic chemists. Through directed evolution of P450BSß hydroxylase, we realize oxyfunctionalization of unactivated C-H bonds in a broad spectrum of aliphatic carboxylic acids with varied chain lengths, functional groups and (hetero-)aromatic moieties in a highly chemo-, regio- and enantioselective fashion (>30 examples, Cß/Cα>20 : 1, >99 % ee). The X-ray structure of the evolved variant, P450BSß -L78I/Q85H/G290I, in complex with palmitic acid well rationalizes the experimentally observed regio- and enantioselectivity, and also reveals a reduced catalytic pocket volume that accounts for the increased reactivity with smaller substrates. This work showcases the potential of employing a biocatalyst to enable a chemical transformation that is particularly challenging by chemical methods.


Assuntos
Ácidos Carboxílicos , Sistema Enzimático do Citocromo P-450 , Biocatálise , Sistema Enzimático do Citocromo P-450/metabolismo , Hidroxilação , Estereoisomerismo
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