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1.
Cell ; 186(4): 786-802.e28, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36754049

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that results from many diverse genetic causes. Although therapeutics specifically targeting known causal mutations may rescue individual types of ALS, these approaches cannot treat most cases since they have unknown genetic etiology. Thus, there is a pressing need for therapeutic strategies that rescue multiple forms of ALS. Here, we show that pharmacological inhibition of PIKFYVE kinase activates an unconventional protein clearance mechanism involving exocytosis of aggregation-prone proteins. Reducing PIKFYVE activity ameliorates ALS pathology and extends survival of animal models and patient-derived motor neurons representing diverse forms of ALS including C9ORF72, TARDBP, FUS, and sporadic. These findings highlight a potential approach for mitigating ALS pathogenesis that does not require stimulating macroautophagy or the ubiquitin-proteosome system.


Assuntos
Esclerose Lateral Amiotrófica , Fosfatidilinositol 3-Quinases , Animais , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Neurônios Motores , Mutação , Proteína FUS de Ligação a RNA/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Modelos Animais de Doenças
2.
Cell ; 182(1): 226-244.e17, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32649875

RESUMO

Lung cancer in East Asia is characterized by a high percentage of never-smokers, early onset and predominant EGFR mutations. To illuminate the molecular phenotype of this demographically distinct disease, we performed a deep comprehensive proteogenomic study on a prospectively collected cohort in Taiwan, representing early stage, predominantly female, non-smoking lung adenocarcinoma. Integrated genomic, proteomic, and phosphoproteomic analysis delineated the demographically distinct molecular attributes and hallmarks of tumor progression. Mutational signature analysis revealed age- and gender-related mutagenesis mechanisms, characterized by high prevalence of APOBEC mutational signature in younger females and over-representation of environmental carcinogen-like mutational signatures in older females. A proteomics-informed classification distinguished the clinical characteristics of early stage patients with EGFR mutations. Furthermore, integrated protein network analysis revealed the cellular remodeling underpinning clinical trajectories and nominated candidate biomarkers for patient stratification and therapeutic intervention. This multi-omic molecular architecture may help develop strategies for management of early stage never-smoker lung adenocarcinoma.


Assuntos
Progressão da Doença , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteogenômica , Fumar/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinógenos/toxicidade , Estudos de Coortes , Citosina Desaminase/metabolismo , Ásia Oriental , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Genoma Humano , Humanos , Metaloproteinases da Matriz/metabolismo , Mutação/genética , Análise de Componente Principal
3.
Nature ; 579(7798): 219-223, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32132712

RESUMO

Ultrathin two-dimensional (2D) semiconducting layered materials offer great potential for extending Moore's law of the number of transistors in an integrated circuit1. One key challenge with 2D semiconductors is to avoid the formation of charge scattering and trap sites from adjacent dielectrics. An insulating van der Waals layer of hexagonal boron nitride (hBN) provides an excellent interface dielectric, efficiently reducing charge scattering2,3. Recent studies have shown the growth of single-crystal hBN films on molten gold surfaces4 or bulk copper foils5. However, the use of molten gold is not favoured by industry, owing to its high cost, cross-contamination and potential issues of process control and scalability. Copper foils might be suitable for roll-to-roll processes, but are unlikely to be compatible with advanced microelectronic fabrication on wafers. Thus, a reliable way of growing single-crystal hBN films directly on wafers would contribute to the broad adoption of 2D layered materials in industry. Previous attempts to grow hBN monolayers on Cu (111) metals have failed to achieve mono-orientation, resulting in unwanted grain boundaries when the layers merge into films6,7. Growing single-crystal hBN on such high-symmetry surface planes as Cu (111)5,8 is widely believed to be impossible, even in theory. Nonetheless, here we report the successful epitaxial growth of single-crystal hBN monolayers on a Cu (111) thin film across a two-inch c-plane sapphire wafer. This surprising result is corroborated by our first-principles calculations, suggesting that the epitaxial growth is enhanced by lateral docking of hBN to Cu (111) steps, ensuring the mono-orientation of hBN monolayers. The obtained single-crystal hBN, incorporated as an interface layer between molybdenum disulfide and hafnium dioxide in a bottom-gate configuration, enhanced the electrical performance of transistors. This reliable approach to producing wafer-scale single-crystal hBN paves the way to future 2D electronics.

4.
Nucleic Acids Res ; 52(D1): D1569-D1578, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37897338

RESUMO

PlantPAN 4.0 (http://PlantPAN.itps.ncku.edu.tw/) is an integrative resource for constructing transcriptional regulatory networks for diverse plant species. In this release, the gene annotation and promoter sequences were expanded to cover 115 species. PlantPAN 4.0 can help users characterize the evolutionary differences and similarities among cis-regulatory elements; furthermore, this system can now help in identification of conserved non-coding sequences among homologous genes. The updated transcription factor binding site repository contains 3428 nonredundant matrices for 18305 transcription factors; this expansion helps in exploration of combinational and nucleotide variants of cis-regulatory elements in conserved non-coding sequences. Additionally, the genomic landscapes of regulatory factors were manually updated, and ChIP-seq data sets derived from a single-cell green alga (Chlamydomonas reinhardtii) were added. Furthermore, the statistical review and graphical analysis components were improved to offer intelligible information through ChIP-seq data analysis. These improvements included easy-to-read experimental condition clusters, searchable gene-centered interfaces for the identification of promoter regions' binding preferences by considering experimental condition clusters and peak visualization for all regulatory factors, and the 20 most significantly enriched gene ontology functions for regulatory factors. Thus, PlantPAN 4.0 can effectively reconstruct gene regulatory networks and help compare genomic cis-regulatory elements across plant species and experiments.


Assuntos
Bases de Dados Genéticas , Regulação da Expressão Gênica de Plantas , Plantas , Regiões Promotoras Genéticas , Redes Reguladoras de Genes , Plantas/genética , Ligação Proteica
5.
PLoS Pathog ; 19(11): e1011500, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37948471

RESUMO

Host cell entry of vaccinia virus (a poxvirus) proceeds through multiple steps that involve many viral proteins to mediate cell infection. Upon binding to cells, vaccinia virus membrane fuses with host membranes via a viral entry fusion protein complex comprising 11 proteins: A16, A21, A28, F9, G3, G9, H2, J5, L1, L5 and O3. Despite vaccinia virus having two infectious forms, mature and enveloped, that have different membrane layers, both forms require an identical viral entry fusion complex for membrane fusion. Components of the poxvirus entry fusion complex that have been structurally assessed to date share no known homology with all other type I, II and III viral fusion proteins, and the large number of fusion protein components renders it a unique system to investigate poxvirus-mediated membrane fusion. Here, we determined the NMR structure of a truncated version of vaccinia A28 protein. We also expressed a soluble H2 protein and showed that A28 interacts with H2 protein at a 1:1 ratio in vitro. Furthermore, we performed extensive in vitro alanine mutagenesis to identify A28 protein residues that are critical for H2 binding, entry fusion complex formation, and virus-mediated membrane fusion. Finally, we used molecular dynamic simulations to model full-length A28-H2 subcomplex in membranes. In summary, we characterized vaccinia virus A28 protein and determined residues important in its interaction with H2 protein and membrane components. We also provide a structural model of the A28-H2 protein interaction to illustrate how it forms a 1:1 subcomplex on a modeled membrane.


Assuntos
Poxviridae , Vacínia , Humanos , Vaccinia virus/metabolismo , Simulação de Dinâmica Molecular , Proteínas Virais de Fusão/metabolismo , Poxviridae/metabolismo , Internalização do Vírus
6.
Nano Lett ; 24(25): 7706-7715, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38869369

RESUMO

Field-free switching (FFS) and spin-orbit torque (SOT)-based neuromorphic characteristics were realized in a W/Pt/Co/NiO/Pt heterostructure with a perpendicular exchange bias (HEB) for brain-inspired neuromorphic computing (NC). Experimental results using NiO-based SOT devices guided the development of fully spin-based artificial synapses and sigmoidal neurons for implementation in a three-layer artificial neural network. This system achieved impressive accuracies of 91-96% when applied to the Modified National Institute of Standards and Technology (MNIST) image data set and 78.85-81.25% when applied to Fashion MNIST images, due presumably to the emergence of robust NiO antiferromagnetic (AFM) ordering. The emergence of AFM ordering favored the FFS with an enhanced HEB, which suppressed the memristivity and reduced the recognition accuracy. This indicates a trade-off between the requirements for solid-state memory and those required for brain-inspired NC devices. Nonetheless, our findings revealed opportunities by which the two technologies could be aligned via controllable exchange coupling.

7.
J Biol Chem ; 299(2): 102842, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36581205

RESUMO

The small GTPase KRAS is frequently mutated in pancreatic cancer and its cooperation with the transcription factor MYC is essential for malignant transformation. The key to oncogenic KRAS and MYC working together is the stabilization of MYC expression due to KRAS activating the extracellular signal-regulated kinase 1/2, which phosphorylates MYC at serine 62 (Ser 62). This prevents the proteasomal degradation of MYC while enhancing its transcriptional activity. Here, we identify how this essential signaling connection between oncogenic KRAS and MYC expression is mediated by the inhibitor of apoptosis protein family member Survivin. This discovery stemmed from our finding that Survivin expression is downregulated upon treatment of pancreatic cancer cells with the KRASG12C inhibitor Sotorasib. We went on to show that oncogenic KRAS increases Survivin expression by activating extracellular signal-regulated kinase 1/2 in pancreatic cancer cells and that treating the cells either with siRNAs targeting Survivin or with YM155, a small molecule that potently blocks Survivin expression, downregulates MYC and strongly inhibited their growth. We further determined that Survivin protects MYC from degradation by blocking autophagy, which then prevents cellular inhibitor of protein phosphatase 2A from undergoing autophagic degradation. Cellular inhibitor of protein phosphatase 2A, by inhibiting protein phosphatase 2A, helps to maintain MYC phosphorylation at Ser 62, thereby ensuring its cooperation with oncogenic KRAS in driving cancer progression. Overall, these findings highlight a novel role for Survivin in mediating the cooperative actions of KRAS and MYC during malignant transformation and raise the possibility that targeting Survivin may offer therapeutic benefits against KRAS-driven cancers.


Assuntos
Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas c-myc , Proteínas Proto-Oncogênicas p21(ras) , Survivina , Humanos , Linhagem Celular Tumoral , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neoplasias Pancreáticas/patologia , Proteína Fosfatase 2/metabolismo , Estabilidade Proteica , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Survivina/genética , Survivina/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Neoplasias Pancreáticas
8.
BMC Genomics ; 25(1): 785, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138417

RESUMO

To reduce the use of antibiotics and chemicals in aquaculture, an edible herb, Bidens pilosa, has been selected as a multifunctional feed additive. Although there has been considerable research into the effects of B. pilosa on poultry, the wider effects of B. pilosa, particularly on the growth and gut microbiota of fish, remain largely unexplored. We aimed to investigate the interactive effects between the host on growth and the gut microbiota using transcriptomics and the gut microbiota in B. pilosa-fed tilapia. In this study, we added 0.5% and 1% B. pilosa to the diet and observed that the growth performance of tilapia significantly increased over 8 weeks of feeding. Comparative transcriptome analysis was performed on RNA sequence profiles obtained from liver and muscle tissues. Functional enrichment analysis revealed that B. pilosa regulates several pathways and genes involved in amino acid metabolism, lipid metabolism, carbohydrate metabolism, endocrine system, signal transduction, and metabolism of other amino acids. The expression of the selected growth-associated genes was validated by qRT-PCR. The qRT-PCR results indicated that B. pilosa may enhance growth performance by activating the expression of the liver igf1 and muscle igf1rb genes and inhibiting the expression of the muscle negative regulator mstnb. Both the enhancement of liver endocrine IGF1/IGF1Rb signaling and the suppression of muscle autocrine/paracrine MSTN signaling induced the expression of myogenic regulatory factors (MRFs), myod1, myog and mrf4 in muscle to promote muscle growth in tilapia. The predicted function of the gut microbiota showed several significantly different pathways that overlapped with the KEGG enrichment results of differentially expressed genes in the liver transcriptomes. This finding suggested that the gut microbiota may influence liver metabolism through the gut-liver axis in B. pilosa-fed tilapia. In conclusion, dietary B. pilosa can regulate endocrine IGF1 signaling and autocrine/paracrine MSTN signaling to activate the expression of MRFs to promote muscle growth and alter the composition of gut bacteria, which can then affect liver amino acid metabolism, carbohydrate metabolism, endocrine system, lipid metabolism, metabolism of other amino acids, and signal transduction in the host, ultimately enhancing growth performance. Our results suggest that B. pilosa has the potential to be a functional additive that can be used as an alternative to reduce antibiotic use as a growth promoter in aquaculture.


Assuntos
Ração Animal , Bidens , Microbioma Gastrointestinal , Tilápia , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Tilápia/crescimento & desenvolvimento , Tilápia/microbiologia , Tilápia/genética , Tilápia/metabolismo , Bidens/metabolismo , Bidens/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Transcriptoma , Fígado/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-39251170

RESUMO

BACKGROUND AND AIMS: Early-onset colorectal cancer (CRC) is increasing globally. While the United States have lowered the age of initiation of screening to 45, other countries still start screening at age 50. In Taiwan, the incidence of CRC has declined in 55-74 year-olds after the initiation of screening, but still increased in those 50-54, potentially due to rising precancerous lesion incidence in 40-49 year-olds. This study aimed to explore the chronological trend of the prevalence of colorectal advanced neoplasms (AN) in the screening population aged 40-54. METHODS: We retrospectively analyzed a screening colonoscopy cohort for prevalence of AN in average-risk subjects aged 40-54 from 2003 to 2019. Logistic regression was used to distinguish cohort effect from time-period effect on the prevalence of AN. RESULTS: In total, 27,805 subjects (52.1% male) men were enrolled. There were notable increases in prevalence of AN in all three age groups during the 17-year span, but these were more rapid in age 40-44 (0.99% to 3.22%) and 45-49 (2.50% to 4.19%). Age 50-54 had higher risk of AN [aOR=1.62(1.19-2.19)] in 2003-2008 but not in later periods [2009-2014: aOR=1.08(0.83-1.41)] and [2015-2019: aOR=0.76(0.56-1.03)] when compared with age 45-49. CONCLUSION: The prevalence of AN in age 40-54 increased in the Taiwanese population, with a later birth cohort having a higher prevalence of AN. However, the prevalence of AN in age 45-49 increased more remarkably and approximated that in age 50-54, which may justify earlier initiation of CRC screening at age 45.

10.
Gastroenterology ; 164(6): 921-936.e1, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36764492

RESUMO

BACKGROUND & AIMS: Aberrant DNA methylation is frequent in colorectal cancer (CRC), but underlying mechanisms and pathologic consequences are poorly understood. METHODS: We disrupted active DNA demethylation genes Tet1 and/or Tdg from ApcMin mice and characterized the methylome and transcriptome of colonic adenomas. Data were compared to human colonic adenocarcinomas (COAD) in The Cancer Genome Atlas. RESULTS: There were increased numbers of small intestinal adenomas in ApcMin mice expressing the TdgN151A allele, whereas Tet1-deficient and Tet1/TdgN151A-double heterozygous ApcMin colonic adenomas were larger with features of erosion and invasion. We detected reduction in global DNA hypomethylation in colonic adenomas from Tet1- and Tdg-mutant ApcMin mice and hypermethylation of CpG islands in Tet1-mutant ApcMin adenomas. Up-regulation of inflammatory, immune, and interferon response genes was present in Tet1- and Tdg-mutant colonic adenomas compared to control ApcMin adenomas. This up-regulation was also seen in murine colonic organoids and human CRC lines infected with lentiviruses expressing TET1 or TDG short hairpin RNA. A 127-gene inflammatory signature separated colonic adenocarcinomas into 4 groups, closely aligned with their microsatellite or chromosomal instability and characterized by different levels of DNA methylation and DNMT1 expression that anticorrelated with TET1 expression. Tumors with the CpG island methylator phenotype (CIMP) had concerted high DNMT1/low TET1 expression. TET1 or TDG knockdown in CRC lines enhanced killing by natural killer cells. CONCLUSIONS: Our findings reveal a novel epigenetic regulation, linked to the type of genomic instability, by which TET1/TDG-mediated DNA demethylation decreases methylation levels and inflammatory/interferon/immune responses. CIMP in CRC is triggered by an imbalance of methylating activities over demethylating activities. These mice represent a model of CIMP CRC.


Assuntos
Adenocarcinoma , Adenoma , Neoplasias do Colo , Neoplasias Colorretais , Animais , Humanos , Camundongos , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenoma/genética , Adenoma/patologia , Carcinogênese/genética , Transformação Celular Neoplásica/genética , Neoplasias do Colo/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Ilhas de CpG/genética , Metilação de DNA , Proteínas de Ligação a DNA/genética , Epigênese Genética , Oxigenases de Função Mista/genética , Fenótipo , Proteínas Proto-Oncogênicas/genética
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