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1.
Cell ; 159(3): 558-71, 2014 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-25417107

RESUMO

The recognition of modified histones by "reader" proteins constitutes a key mechanism regulating gene expression in the chromatin context. Compared with the great variety of readers for histone methylation, few protein modules that recognize histone acetylation are known. Here, we show that the AF9 YEATS domain binds strongly to histone H3K9 acetylation and, to a lesser extent, H3K27 and H3K18 acetylation. Crystal structural studies revealed that AF9 YEATS adopts an eight-stranded immunoglobin fold and utilizes a serine-lined aromatic "sandwiching" cage for acetyllysine readout, representing a novel recognition mechanism that is distinct from that of known acetyllysine readers. ChIP-seq experiments revealed a strong colocalization of AF9 and H3K9 acetylation genome-wide, which is important for the chromatin recruitment of the H3K79 methyltransferase DOT1L. Together, our studies identified the evolutionarily conserved YEATS domain as a novel acetyllysine-binding module and established a direct link between histone acetylation and DOT1L-mediated H3K79 methylation in transcription control.


Assuntos
Código das Histonas , Metiltransferases/química , Metiltransferases/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Acetilação , Sequência de Aminoácidos , Regulação da Expressão Gênica , Histona Acetiltransferases/química , Histona Acetiltransferases/metabolismo , Histona-Lisina N-Metiltransferase , Histonas/metabolismo , Humanos , Metilação , Modelos Moleculares , Dados de Sequência Molecular , Processamento de Proteína Pós-Traducional , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Transcrição Gênica
2.
EMBO J ; 42(19): e113328, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37641865

RESUMO

Eukaryotic organisms adapt to environmental fluctuations by altering their epigenomic landscapes and transcriptional programs. Nucleosomal histones carry vital epigenetic information and regulate gene expression, yet the mechanisms underlying chromatin-bound histone exchange remain elusive. Here, we found that histone H2Bs are globally degraded in Caenorhabditis elegans during starvation. Our genetic screens identified mutations in ubiquitin and ubiquitin-related enzymes that block H2B degradation in starved animals, identifying lysine 31 as the crucial residue for chromatin-bound H2B ubiquitination and elimination. Retention of aberrant nucleosomal H2B increased the association of the FOXO transcription factor DAF-16 with chromatin, generating an ectopic gene expression profile detrimental to animal viability when insulin/IGF signaling was reduced in well-fed animals. Furthermore, we show that the ubiquitin-proteasome system regulates chromosomal histone turnover in human cells. During larval development, C. elegans epidermal cells undergo H2B turnover after fusing with the epithelial syncytium. Thus, histone degradation may be a widespread mechanism governing dynamic changes of the epigenome.


Assuntos
Caenorhabditis elegans , Histonas , Animais , Humanos , Histonas/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Insulina/metabolismo , Cromatina , Ubiquitinação , Ubiquitina/metabolismo
3.
Nature ; 577(7788): 121-126, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31853060

RESUMO

Modifications of histone proteins have essential roles in normal development and human disease. Recognition of modified histones by 'reader' proteins is a key mechanism that mediates the function of histone modifications, but how the dysregulation of these readers might contribute to disease remains poorly understood. We previously identified the ENL protein as a reader of histone acetylation via its YEATS domain, linking it to the expression of cancer-driving genes in acute leukaemia1. Recurrent hotspot mutations have been found in the ENL YEATS domain in Wilms tumour2,3, the most common type of paediatric kidney cancer. Here we show, using human and mouse cells, that these mutations impair cell-fate regulation by conferring gain-of-function in chromatin recruitment and transcriptional control. ENL mutants induce gene-expression changes that favour a premalignant cell fate, and, in an assay for nephrogenesis using murine cells, result in undifferentiated structures resembling those observed in human Wilms tumour. Mechanistically, although bound to largely similar genomic loci as the wild-type protein, ENL mutants exhibit increased occupancy at a subset of targets, leading to a marked increase in the recruitment and activity of transcription elongation machinery that enforces active transcription from target loci. Furthermore, ectopically expressed ENL mutants exhibit greater self-association and form discrete and dynamic nuclear puncta that are characteristic of biomolecular hubs consisting of local high concentrations of regulatory factors. Such mutation-driven ENL self-association is functionally linked to enhanced chromatin occupancy and gene activation. Collectively, our findings show that hotspot mutations in a chromatin-reader domain drive self-reinforced recruitment, derailing normal cell-fate control during development and leading to an oncogenic outcome.


Assuntos
Linhagem da Célula , Cromatina/genética , Proteínas de Ligação a DNA/metabolismo , Mutação com Ganho de Função , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Células HEK293 , Humanos , Camundongos , Néfrons/metabolismo , Néfrons/patologia , Fatores de Transcrição/química , Fatores de Transcrição/genética
4.
Proc Natl Acad Sci U S A ; 120(42): e2302780120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37812701

RESUMO

Brain L-serine is critical for neurodevelopment and is thought to be synthesized solely from glucose. In contrast, we found that the influx of L-serine across the blood-brain barrier (BBB) is essential for brain development. We identified the endothelial Slc38a5, previously thought to be a glutamine transporter, as an L-serine transporter expressed at the BBB in early postnatal life. Young Slc38a5 knockout (KO) mice exhibit developmental alterations and a decrease in brain L-serine and D-serine, without changes in serum or liver amino acids. Slc38a5-KO brains exhibit accumulation of neurotoxic deoxysphingolipids, synaptic and mitochondrial abnormalities, and decreased neurogenesis at the dentate gyrus. Slc38a5-KO pups exhibit motor impairments that are affected by the administration of L-serine at concentrations that replenish the serine pool in the brain. Our results highlight a critical role of Slc38a5 in supplying L-serine via the BBB for proper brain development.


Assuntos
Barreira Hematoencefálica , Encéfalo , Camundongos , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Transporte Biológico , Transporte de Íons , Serina/metabolismo , Camundongos Knockout
5.
Genes Dev ; 32(1): 58-69, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29437725

RESUMO

Histone acetylation is associated with active transcription in eukaryotic cells. It helps to open up the chromatin by neutralizing the positive charge of histone lysine residues and providing binding platforms for "reader" proteins. The bromodomain (BRD) has long been thought to be the sole protein module that recognizes acetylated histones. Recently, we identified the YEATS domain of AF9 (ALL1 fused gene from chromosome 9) as a novel acetyl-lysine-binding module and showed that the ENL (eleven-nineteen leukemia) YEATS domain is an essential acetyl-histone reader in acute myeloid leukemias. The human genome encodes four YEATS domain proteins, including GAS41, a component of chromatin remodelers responsible for H2A.Z deposition onto chromatin; however, the importance of the GAS41 YEATS domain in human cancer remains largely unknown. Here we report that GAS41 is frequently amplified in human non-small cell lung cancer (NSCLC) and is required for cancer cell proliferation, survival, and transformation. Biochemical and crystal structural studies demonstrate that GAS41 binds to histone H3 acetylated on H3K27 and H3K14, a specificity that is distinct from that of AF9 or ENL. ChIP-seq (chromatin immunoprecipitation [ChIP] followed by high-throughput sequencing) analyses in lung cancer cells reveal that GAS41 colocalizes with H3K27ac and H3K14ac on the promoters of actively transcribed genes. Depletion of GAS41 or disruption of the interaction between its YEATS domain and acetylated histones impairs the association of histone variant H2A.Z with chromatin and consequently suppresses cancer cell growth and survival both in vitro and in vivo. Overall, our study identifies GAS41 as a histone acetylation reader that promotes histone H2A.Z deposition in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Amplificação de Genes , Genes cdc , Histonas/fisiologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Regiões Promotoras Genéticas , Domínios e Motivos de Interação entre Proteínas , Fatores de Transcrição/química , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia
6.
J Cell Mol Med ; 28(9): e18372, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38747737

RESUMO

Multicellular organisms have dense affinity with the coordination of cellular activities, which severely depend on communication across diverse cell types. Cell-cell communication (CCC) is often mediated via ligand-receptor interactions (LRIs). Existing CCC inference methods are limited to known LRIs. To address this problem, we developed a comprehensive CCC analysis tool SEnSCA by integrating single cell RNA sequencing and proteome data. SEnSCA mainly contains potential LRI acquisition and CCC strength evaluation. For acquiring potential LRIs, it first extracts LRI features and reduces the feature dimension, subsequently constructs negative LRI samples through K-means clustering, finally acquires potential LRIs based on Stacking ensemble comprising support vector machine, 1D-convolutional neural networks and multi-head attention mechanism. During CCC strength evaluation, SEnSCA conducts LRI filtering and then infers CCC by combining the three-point estimation approach and single cell RNA sequencing data. SEnSCA computed better precision, recall, accuracy, F1 score, AUC and AUPR under most of conditions when predicting possible LRIs. To better illustrate the inferred CCC network, SEnSCA provided three visualization options: heatmap, bubble diagram and network diagram. Its application on human melanoma tissue demonstrated its reliability in CCC detection. In summary, SEnSCA offers a useful CCC inference tool and is freely available at https://github.com/plhhnu/SEnSCA.


Assuntos
Comunicação Celular , Análise de Célula Única , Humanos , Ligantes , Análise de Célula Única/métodos , Software , Biologia Computacional/métodos , Algoritmos , Máquina de Vetores de Suporte , Análise de Sequência de RNA/métodos , Melanoma/metabolismo , Melanoma/patologia , Melanoma/genética , Proteoma/metabolismo , Redes Neurais de Computação
7.
Small ; : e2311779, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530085

RESUMO

Micrometer-sized Si particles are beneficial to practical lithium-ion batteries in regard to low cost and high volumetric energy density in comparison with nanostructured Si anodes. However, both the issues of electrical contact loss and overgrowth of solid electrolyte interface for microscale Si induced by colossal volume change still remain to be addressed. Herein, a scalable and template-free method is introduced to fabricate yolk-shell structured Si anode from commercially available Si microparticles. The void is created via a one-step alkali etching process with the remaining silicon core as the yolk, and a double-walled shell is formed from simultaneous in situ growth of the conformal native oxide layer and subsequent carbon coating. In this configuration, the well-defined void spaces allow the Si core to expand without compromising structural integrity, while the double-walled shell acts as a static capsule to confine silicon fragments despite likely particle fracture. Therefore, electrical connectivity is maintained on both the particle and electrode level during deep galvanostatic cycling, and the solid-electrolyte interface is stabilized on the shell surface. Owing to the benefits of tailored design, excellent cycling stability (capacity retention of 95% after 100 cycles) and high coulombic efficiency (99.5%) are realized in a practical full-cell demonstration.

8.
Opt Express ; 32(9): 15801-15812, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859221

RESUMO

In this paper, we introduce the application of multiple-mode index modulation (MMIM) to filter bank multi-carrier (FBMC) for the first time in visible light communication (VLC) systems. Additionally, we propose a group-interleaved precoding (GIP) technique to enhance the performance of MM-FBMC-IM-based VLC systems. The GIP technique reduces complexity in precoding by grouping and achieves equalization of the signal-to-noise ratio (SNR) through subcarrier interleaving. Furthermore, we develop a robust low-complexity maximum likelihood (LCML) detector, which can maintain the same computational complexity as a conventional LCML detector and achieve similar performance as an ML detector. The effectiveness and superiority of the proposed MM-FBMC-IM-based VLC system with GIP are demonstrated through comprehensive validation by both simulation and experimental results.

9.
BMC Cancer ; 24(1): 46, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195455

RESUMO

BACKGROUND: Prompt response to induction chemotherapy is a prognostic factor in pediatric acute myeloid leukemia. In this study, we aimed to evaluate the prognostic significance of multiparametric flow cytometry-minimal residual disease (MFC-MRD), assessed at the end of the first and second induction courses. METHODS: MFC-MRD was performed at the end of the first induction (TP1) in 524 patients and second induction (TP2) in 467 patients who were treated according to the modified Medical Research Council (UK) acute myeloid leukemia 15 protocol. RESULTS: Using a 0.1% cutoff level, patients with MFC-MRD at the two time points had lower event-free survival and overall survival. Only the TP2 MFC-MRD level could predict the outcome in a separate analysis of high and intermediate risks based on European LeukemiaNet risk stratification and KMT2A rearrangement. The TP2 MFC-MRD level could further differentiate the prognosis of patients into complete remission or non-complete remission based on morphological evaluation. Multivariate analysis indicated the TP2 MFC-MRD level as an independent adverse prognostic factor for event-free survival and overall survival. When comparing patients with MFC-MRD ≥ 0.1%, those who underwent hematopoietic stem cell transplant during the first complete remission had significantly higher 5-year event-free survival and overall survival and lower cumulative incidence of relapse than those who only received consolidation chemotherapy. CONCLUSIONS: The TP2 MFC-MRD level can predict the outcomes in pediatric patients with acute myeloid leukemia and help stratify post-remission treatment.


Assuntos
Leucemia Mieloide , Humanos , Criança , Citometria de Fluxo , Neoplasia Residual , Prognóstico , Movimento Celular , Resposta Patológica Completa
10.
Eur Radiol ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374482

RESUMO

OBJECTIVES: To evaluate the additional advantages of integrating contrast-enhanced ultrasound (CEUS) into the Ovarian-Adnexal Reporting and Data System (O-RADS) ultrasound (US) for the characterization of adnexal lesions with solid components. MATERIALS AND METHODS: This prospective multicenter study recruited women suspected of having adnexal lesions with solid components between September 2021 and December 2022. All patients scheduled for surgery underwent preoperative CEUS and US examinations. The lesions were categorized according to the O-RADS US system, and quantitative CEUS indexes were recorded. Pathological results served as the reference standard. Univariable and multivariable analyses were performed to identify risk factors for malignancy in adnexal lesions with solid components. Receiver operating characteristic (ROC) curve analysis was employed to assess diagnostic performance. RESULTS: A total of 180 lesions in 175 women were included in the study. Among these masses, 80 were malignant and 100 were benign. Multivariable analysis revealed that serum CA-125, the presence of acoustic shadowing, and peak intensity (PI) ratio (PImass/PIuterus) of solid components on CEUS were independently associated with adnexal malignancy. The modified CEUS risk stratification model demonstrated superior diagnostic value in assessing adnexal lesions with solid components compared to O-RADS US (AUC: 0.91 vs 0.78, p < 0.001) and exhibited comparable performance to the Assessment of Different NEoplasias in the adnexa (ADNEX) model (AUC 0.91 vs 0.86, p = 0.07). CONCLUSION: Our findings underscore the potential value of CEUS as an adjunctive tool for enhancing the precision of diagnostic evaluations of O-RADS US. CLINICAL RELEVANCE STATEMENT: The promising performance of the modified CEUS risk stratification model suggests its potential to mitigate unnecessary surgeries in the characterization of adnexal lesions with solid components. KEY POINTS: • The additional value of CEUS to O-RADS US in distinguishing between benign and malignant adnexal lesions with solid components requires further evaluation. • The modified CEUS risk stratification model displayed superior diagnostic value and specificity in characterizing adnexal lesions with solid components when compared to O-RADS US. • The inclusion of CEUS demonstrated potential in reducing the need for unnecessary surgeries in the characterization of adnexal lesions with solid components.

11.
Am J Bot ; : e16319, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38641926

RESUMO

PREMISE: Endophytic and mycorrhizal fungi are crucial in facilitating plant nutrition acquisition and stress tolerance. In epiphytic habitats, plants face nutrition and water stress, but their roots are mostly nonmycorrhizal and especially lacking in arbuscular mycorrhizal associations. Ophioderma pendulum is an epiphytic fern with a partially mycoheterotrophic lifestyle, likely heavily reliant on symbiotic fungi. To characterize fungal associations in the sporophyte of O. pendulum, we focused on leaves and roots of O. pendulum, seeking to reveal the fungal communities in these organs. METHODS: Roots and leaves from O. pendulum in a subtropical forest were examined microscopically to observe the morphology of fungal structures and determine the percentage of various fungal structures in host tissues. Fungal composition was profiled using metabarcoding techniques that targeted ITS2 of the nuclear ribosomal DNA. RESULTS: Roots were consistently colonized by arbuscular mycorrhizal fungi (Glomeromycota), especially Acaulospora. Unlike previous findings on epiphytic ferns, dark septate endophytes were rare in O. pendulum roots. Leaves were predominantly colonized by Ascomycota fungi, specifically the classes Dothideomycetes (46.88%), Eurotiomycetes (11.51%), Sordariomycetes (6.23%), and Leotiomycetes (6.14%). Across sampling sites, fungal community compositions were similar in the roots but differed significantly in the leaves. CONCLUSIONS: Ophioderma pendulum maintains stable, single-taxon-dominant communities in the roots, primarily featuring arbuscular mycorrhizal fungi, whereas the leaves may harbor opportunistic fungal colonizers. Our study underlines the significance of mycorrhizal fungi in the adaptation of epiphytic ferns.

12.
Org Biomol Chem ; 22(24): 4978-4986, 2024 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-38832762

RESUMO

Ganoderma lucidum, a fungus used in traditional Chinese medicine, is known for its medicinal value attributed to its active components called Ganoderma triterpenoids (GTs). However, the limited isolation rate of these GTs has hindered their potential as promising drug candidates. Therefore, it is imperative to achieve large-scale preparation of GTs. In this study, four GTs were effectively synthesised from lanosterol. The antitumor activity of these GTs was evaluated in vivo. Endertiin B exhibited potent inhibitory activity against breast cancer cells (9.85 ± 0.91 µM and 12.12 ± 0.95 µM). Further investigations demonstrated that endertiin B significantly upregulated p21 and p27 and downregulated cyclinD1 expression, arresting the cell cycle at the G0/G1 phase and inducing apoptosis by decreasing BCL-2 and increasing BAX and BAK levels. Additionally, endertiin B was found to reduce the expression of proteins associated with the PI3K-AKT signaling pathway. To summarize, endertiin B effectively inhibited cell proliferation by blocking the cell cycle and inducing apoptosis through the PI3K-AKT pathway.


Assuntos
Antineoplásicos , Apoptose , Proliferação de Células , Reishi , Triterpenos , Triterpenos/farmacologia , Triterpenos/química , Triterpenos/síntese química , Triterpenos/isolamento & purificação , Reishi/química , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Animais , Camundongos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Relação Estrutura-Atividade , Feminino , Ciclo Celular/efeitos dos fármacos , Estrutura Molecular
13.
Bioorg Chem ; 144: 107166, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38308998

RESUMO

Twelve phthalideisoquinoline hemiacetal alkaloids including eight new ones (1-8) and one natural alkaloid characterized by an aziridine moiety with unassigned NMR data (9), were isolated and identified from the bulbs of Corydalis decumbens. Their structures were established by comprehensive analyses of HRESIMS, NMR, X-ray crystallography, and ECD analyses. The unambiguously established structures of the phthalideisoquinoline hemiacetal alkaloids indicated that the absolute configurations of C-1, C-9, and C-7' were confusable only relied on coupling constants. A summary of their ECD spectra was concluded and provided an insight for C-1, C-9, and C-7' absolute configuration assignment. These new compounds were evaluated to induce autophagy flux through flow cytometry analysis. Moreover, compounds 2 and 6 could significantly induce autophagy and inhibit Tau pathology by AMPK-ULK1 pathway activation, which provided an avenue for anti-AD lead compounds discovery.


Assuntos
Alcaloides , Corydalis , Corydalis/química , Proteínas Quinases Ativadas por AMP/metabolismo , Alcaloides/química , Espectroscopia de Ressonância Magnética , Autofagia
14.
Environ Res ; 249: 118385, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38331140

RESUMO

Silkworm pupae, by-product of sericulture industry, is massively discarded. The degradation rate of silkworm pupae protein is critical to further employment, which reduces the impact of waste on the environment. Herein, magnetic Janus mesoporous silica nanoparticles immobilized proteinase K mutant T206M and Mucor circinelloides aspartic protease were employed in the co-degradation. The thermostability of T206M improved by enhancing structural rigidity (t1/2 by 30 min and T50 by 5 °C), prompting the degradation efficiency. At 65 °C and pH 7, degradation rate reached the highest of 61.7%, which improved by 26% compared with single free protease degradation. Besides, the immobilized protease is easy to separate and reuse, which maintains 50% activity after 10 recycles. Therefore, immobilized protease co-degradation was first applied to the development and utilization of silkworm pupae resulting in the release of promising antioxidant properties and reduces the environmental impact by utilizing a natural and renewable resource.


Assuntos
Bombyx , Endopeptidase K , Nanopartículas de Magnetita , Mucor , Pupa , Bombyx/metabolismo , Animais , Mucor/enzimologia , Nanopartículas de Magnetita/química , Endopeptidase K/metabolismo , Enzimas Imobilizadas/metabolismo , Enzimas Imobilizadas/química , Ácido Aspártico Proteases/metabolismo , Ácido Aspártico Proteases/química , Proteínas de Insetos/metabolismo , Proteínas de Insetos/química
15.
Mol Cell ; 62(2): 181-193, 2016 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-27105114

RESUMO

Recognition of histone covalent modifications by chromatin-binding protein modules ("readers") constitutes a major mechanism for epigenetic regulation, typified by bromodomains that bind acetyllysine. Non-acetyl histone lysine acylations (e.g., crotonylation, butyrylation, propionylation) have been recently identified, but readers that prefer these acylations have not been characterized. Here we report that the AF9 YEATS domain displays selectively higher binding affinity for crotonyllysine over acetyllysine. Structural studies revealed an extended aromatic sandwiching cage with crotonyl specificity arising from π-aromatic and hydrophobic interactions between crotonyl and aromatic rings. These features are conserved among the YEATS, but not the bromodomains. Using a cell-based model, we showed that AF9 co-localizes with crotonylated histone H3 and positively regulates gene expression in a YEATS domain-dependent manner. Our studies define the evolutionarily conserved YEATS domain as a family of crotonyllysine readers and specifically demonstrate that the YEATS domain of AF9 directly links histone crotonylation to active transcription.


Assuntos
Crotonatos/metabolismo , Histonas/metabolismo , Proteínas Nucleares/metabolismo , Processamento de Proteína Pós-Traducional , Transcrição Gênica , Ativação Transcricional , Acetilação , Animais , Sítios de Ligação , Montagem e Desmontagem da Cromatina , Epigênese Genética , Células HEK293 , Histonas/química , Histonas/genética , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lisina , Camundongos , Modelos Moleculares , Mutação , Proteínas Nucleares/química , Proteínas Nucleares/genética , Domínios Proteicos , Células RAW 264.7 , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição , Transfecção
16.
Mol Cell ; 63(3): 470-84, 2016 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-27477906

RESUMO

Histone acetylation, including acetylated H3K14 (H3K14ac), is generally linked to gene activation. Monomethylated histone H3 lysine 4 (H3K4me1), together with other gene-activating marks, denotes active genes. In contrast to usual gene-activating functions of H3K14ac and H3K4me1, we here show that the dual histone modification mark H3K4me1-H3K14ac is recognized by ZMYND8 (also called RACK7) and can function to counteract gene expression. We identified ZMYND8 as a transcriptional corepressor of the H3K4 demethylase JARID1D. ZMYND8 antagonized the expression of metastasis-linked genes, and its knockdown increased the cellular invasiveness in vitro and in vivo. The plant homeodomain (PHD) and Bromodomain cassette in ZMYND8 mediated the combinatorial recognition of H3K4me1-H3K14ac and H3K4me0-H3K14ac by ZMYND8. These findings uncover an unexpected role for the signature H3K4me1-H3K14ac in attenuating gene expression and reveal a metastasis-suppressive epigenetic mechanism in which ZMYND8's PHD-Bromo cassette couples H3K4me1-H3K14ac with downregulation of metastasis-linked genes.


Assuntos
Movimento Celular , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias da Próstata/metabolismo , Receptores de Superfície Celular/metabolismo , Acetilação , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Histonas/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Masculino , Camundongos Nus , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Modelos Moleculares , Invasividade Neoplásica , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Interferência de RNA , Receptores de Quinase C Ativada , Receptores de Superfície Celular/genética , Fatores de Tempo , Transcrição Gênica , Transfecção , Carga Tumoral , Proteínas Supressoras de Tumor
17.
Artigo em Inglês | MEDLINE | ID: mdl-38662115

RESUMO

OBJECTIVE: This purpose of this study is to investigate the effectiveness and safety of utilizing the arterial spin-labeling (ASL) combined with diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) combined with DWI double mismatch in the endovascular treatment of patients diagnosed with wake-up stroke (WUS). METHODS: In this single-center trial, patients diagnosed with WUS underwent thrombectomy if acute ischemic lesions were observed on DWI indicating large precerebral circulation occlusion. Patients with no significant parenchymal hypersignal on FLAIR and ASL imaging showing a hypoperfusion tissue to infarct core volume ratio of at least 1.2 were included. The participants were divided into groups receiving endovascular thrombectomy plus medical therapy or medical therapy alone, based on their subjective preference. Functional outcomes were assessed using the ordinal score on the modified Rankin scale (mRs) at 90 days, along with the rate of functional independence. RESULTS: In this study, a total of 77 patients were included, comprising 38 patients in the endovascular therapy group and 39 patients in the medical therapy group. The endovascular therapy group exhibited more favorable changes in the distribution of functional prognosis measured by mRs at 90 days, compared to the medical therapy group (adjusted common odds ratio, 3.25; 95% CI, 1.03 to 10.26; P < 0.01). Additionally, the endovascular therapy group had a higher proportion of patients achieving functional independence (odds ratio, 4.0; 95% CI, 1.36 to 11.81; P < 0.01). Importantly, there were no significant differences observed in the incidence of intracranial hemorrhage or mortality rates between the two groups. CONCLUSION: Guided by the ASL-DWI and FLAIR-DWI double mismatch, endovascular thrombectomy combined with standard medical treatment appears to yield superior functional outcomes in patients with WUS and large vessel occlusion compared to standard medical treatment alone.

18.
J Clin Apher ; 39(1): e22103, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38098278

RESUMO

The purpose of this retrospective study is to compare the efficacy and safety of the centrifugal separation therapeutic plasma exchange (TPE) using citrate anticoagulant (cTPEc) with membrane separation TPE using heparin anticoagulant (mTPEh) in liver failure patients. The patients treated by cTPEc were defined as cTPEc group and those treated by mTPEh were defined as mTPEh group, respectively. Clinical characteristics were compared between the two groups. Survival analyses of two groups and subgroups classified by the model for end-stage liver disease (MELD) score were performed by Kaplan-Meier method and were compared by the log-rank test. In this study, there were 51 patients in cTPEc group and 18 patients in mTPEh group, respectively. The overall 28-day survival rate was 76% (39/51) in cTPEc group and 61% (11/18) in mTPEh group (P > .05). The 90-day survival rate was 69% (35/51) in cTPEc group and 50% (9/18) in mTPEh group (P > .05). MELD score = 30 was the best cut-off value to predict the prognosis of patients with liver failure treated with TPE, in mTPEh group as well as cTPEc group. The median of total calcium/ionized calcium ratio (2.84, range from 2.20 to 3.71) after cTPEc was significantly higher than the ratio (1.97, range from 1.73 to 3.19) before cTPEc (P < .001). However, there was no significant difference between the mean concentrations of total calcium before cTPEc and at 48 h after cTPEc. Our study concludes that there was no statistically significant difference in survival rate and complications between cTPEc and mTPEh groups. The liver failure patients tolerated cTPEc treatment via peripheral vascular access with the prognosis similar to mTPEh. The prognosis in patients with MELD score < 30 was better than in patients with MELD score ≥ 30 in both groups. In this study, the patients with acute liver failure (ALF) and acute on chronic liver failure (ACLF) treated with cTPEc tolerated the TPE frequency of every other day without significant clinical adverse event of hypocalcemia with similar outcomes to the mTPEh treatment. For liver failure patients treated with cTPEc, close clinical observation and monitoring ionized calcium are necessary to ensure the patients' safety.


Assuntos
Insuficiência Hepática Crônica Agudizada , Doença Hepática Terminal , Humanos , Insuficiência Hepática Crônica Agudizada/terapia , Troca Plasmática/métodos , Estudos Retrospectivos , Heparina/uso terapêutico , Cálcio , Doença Hepática Terminal/terapia , Índice de Gravidade de Doença , Anticoagulantes/uso terapêutico
19.
J Fish Dis ; 47(3): e13893, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38062566

RESUMO

Enterospora epinepheli is an intranuclear microsporidian parasite causing serious emaciative disease in hatchery-bred juvenile groupers (Epinephelus spp.). Rapid and sensitive detection is urgently needed as its chronic infection tends to cause emaciation as well as white faeces syndrome and results in fry mortality. This study established a TaqMan probe-based real-time quantitative PCR assays targeting the small subunit rRNA (SSU) gene of E. epinepheli. The relationship between the standard curve of cycle threshold (Ct) and the logarithmic starting quantity (SQ) was determined as Ct = -3.177 lg (SQ) + 38.397. The correlation coefficient (R2 ) was 0.999, and the amplification efficiency was 106.4%. The detection limit of the TaqMan probe-based qPCR assay was 1.0 × 101 copies/µL and that is 100 times sensitive than the traditional PCR method. There is no cross-reaction with other aquatic microsporidia such as Ecytonucleospora hepatopenaei, Nucleospora hippocampi, Potaspora sp., Ameson portunus. The intra-assay and inter-assay showed great repeatability and reproducibility. In addition, the test of clinical samples showed that this assay effectively detected E. epinepheli in the grouper's intestine tissue. The established TaqMan qPCR assays will be a valuable diagnostic tool for the epidemiological investigation as well as prevention and control of E. epinepheli.


Assuntos
Apansporoblastina , Bass , Doenças dos Peixes , Microsporídios , Animais , Bass/genética , Reprodutibilidade dos Testes , Doenças dos Peixes/diagnóstico , Melhoramento Vegetal , Microsporídios/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade
20.
Biomed Chromatogr ; 38(5): e5838, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38342982

RESUMO

Strobilanthes sarcorrhiza (CTS) is a medicinal plant with various pharmacological effects such as tonifying kidney and anti-inflammatory. However, the chemical composition and difference of its four parts (leaves, stems, rhizomes, and root tubers) have been rarely reported. In this study, ultrafast flow liquid chromatography coupled with quadrupole-time-of-flight MS was applied to analyze the chemical profile of CTS and identify 55 compounds, including terpenoids, phenylethanol glycosides, fatty acid derivatives, chain glycosides, flavonoid glycosides, and others. Among these compounds, 34 compounds were first identified in CTS. They were mainly terpenoids, phenylethanol glycosides, fatty acid derivatives, and so forth. Multivariate statistical analysis, such as principal component analysis and orthogonal partial least squares-discriminant analysis were also used to evaluate the difference in chemical compounds from the four parts of CTS. The results showed that phenylethanol glycosides were the main compounds of the underground parts, while terpenoids were the main compounds of the aboveground parts. This study revealed the chemical diversity and similarity of CTS and suggested that the rhizomes could be used as an alternative medicinal part to improve the resource utilization of CTS.


Assuntos
Espectrometria de Massas , Análise Multivariada , Espectrometria de Massas/métodos , Cromatografia Líquida/métodos , Extratos Vegetais/química , Terpenos/análise , Terpenos/química , Glicosídeos/análise , Glicosídeos/química , Cromatografia Líquida de Alta Pressão/métodos
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