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1.
Water Sci Technol ; 81(7): 1507-1517, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32616702

RESUMO

The main point of this research is to assess the applicability of condensed molasses soluble (CMS), which is an organic by-product of lysine fermentation, as an environmentally friendly complexing agent in rhizofiltration of heavy metal contaminated acid mine drainage (AMD). First, the ecotoxicological properties (growth inhibition, seed germination) of CMS were examined with often applied indicator plant species such as duckweed (Lemna minor) and lettuce (Lactuca sativa) so as to define the possible applicable CMS concentration. Then the heavy metal accumulation and translocation properties of root accumulator plant species, i.e. common reed (Phragmites australis) and sedge (Carex flacca), were studied to optimize CMS concentration for rhizofiltration. Due to the CMS application, significant increase in bioaccumulation was detected in the case of every examined heavy metal (As, Cd, Cu, Pb and Zn) at the end of the experiment. Results also showed that CMS increased the heavy metal concentration in shoots, but did not affect the root accumulation characteristics of the plants. Furthermore, CMS treated plants accumulated heavy metals at higher rates in their roots compared to control. The results suggest that CMS is a viable additive and a complexing agent to aid rhizofiltration of heavy metal contaminated AMD.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Biodegradação Ambiental , Fermentação , Lisina , Mineração , Raízes de Plantas
2.
J Clin Pediatr Dent ; 44(3): 174-179, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32644890

RESUMO

Objective: The aim of the present study was to evaluate the reduction in bacterial loading using Papacarie and Carisolv as an irrigating solution in pulpectomized primary molars. Study design: A controlled, randomized clinical trial involving 120 necrotic canals from both genders between 3 and 7 years old children were included, 30 irrigated with Papacarie [ group I], Carisolv [ group II], 1% NaOCl gel [ group III] and 1% Na0Cl solution [group IV ] each; in all cases, 2 microbiological samples from within the canals were taken with sterile paper points, the first after the canal opening and before the first irrigation, and the second after instrumentation and final irrigation, before obturation. All samples were evaluated by Agar plate method. Results: The results were statistically analyzed by ANOVA. After analyzing samples before and after irrigation in all the groups, a strong significant decrease in bacterial load [ p = < 0.001 ] was found with Papacarie and Carisolv. Conclusion: Papacarie and Carisolv can be suggested as an alternative irrigant for pulpectomy of necrotic teeth.


Assuntos
Dente Molar , Irrigantes do Canal Radicular , Criança , Pré-Escolar , Cavidade Pulpar , Feminino , Ácido Glutâmico , Humanos , Leucina , Lisina , Masculino , Papaína , Preparo de Canal Radicular , Hipoclorito de Sódio
3.
Medicine (Baltimore) ; 99(22): e20372, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32481420

RESUMO

The present study investigated the effectiveness of a Carisolv III + 0.5% sodium hypochlorite (NaOCl)-based root canal irrigant for smear layer removal.Forty maxillary incisors were randomly divided into 4 groups (n = 10 per group). The canals in group A (experimental) were prepared with 0.5% NaOCl, and Carisolv III and 0.5% NaOCl was used for the final washing; groups B and C (positive controls) used 2% and 5.25% NaOCl, respectively; and group D (negative control) used phosphate-buffered saline (PBS). Ethylenediaminetetraacetic acid (EDTA) was used for all of the groups. A 5-point scoring scale and scanning electron microscopy were used to evaluate the effectiveness of the irrigants. The canals were consistently cleaner in the coronal and middle thirds than in the apical thirds (P < .05).For cleaning the root canals, 5.25% NaOCl was more effective than 2% NaOCl, 0.5% NaOCl + Carisolv III, and phosphate-buffered saline , respectively (P < .05). The 2% NaOCl solution showed similar results to 0.5% NaOCl + Carisolv III (P > .05). The combination of 5.25% NaOCl and 17% EDTA remains the most effective irrigant for removal of the root canal smear layer.A combination of Carisolv III + 0.5% NaOCl (with 17% EDTA) showed a cleaning ability similar to that of 2% NaOCl (with 17% EDTA).


Assuntos
Ácido Glutâmico/uso terapêutico , Leucina/uso terapêutico , Lisina/uso terapêutico , Irrigantes do Canal Radicular/uso terapêutico , Tratamento do Canal Radicular/métodos , Hipoclorito de Sódio/uso terapêutico , Adulto , Cavidade Pulpar/cirurgia , Feminino , Humanos , Técnicas In Vitro , Incisivo/cirurgia , Masculino , Pessoa de Meia-Idade
4.
Anticancer Res ; 40(5): 2801-2812, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32366427

RESUMO

BACKGROUND/AIM: The influence of a polyurethane-based tissue adhesive (TissuGlu®) on common complications following breast surgery was investigated. PATIENTS AND METHODS: Within a Randomized-Controlled-Trial 70 women (n=35 TissuGlu®, n=35 drain) underwent a mastectomy with or without sentinel lymph node excision (SLNE), followed by a 90-day postoperative follow-up. RESULTS: Postoperative interventions: Non-inferiority of the application of TissuGlu® was seen. Pain-Level/ Hospitalization: A statistically significant pain reduction from day four onwards (p<0.001) and a shorter hospitalization period (p<0.001) was observed. In contrast, the TissuGlu® group showed increased mean puncture incidence (p=0.013), and increased puncture volume (p=0.021). CONCLUSION: Application of the polyurethane-based tissue adhesive TissuGlu® after mastectomy, with or without SLNE, showed potential for improvement of the clinical outcome. In contrast, high intervention rates and increased puncture volume, caused by recurring seromas following application of the surgical adhesive TissuGlu®, have a negative impact on the patient-specific convalescence.


Assuntos
Adesivos/efeitos adversos , Lisina/efeitos adversos , Mastectomia/efeitos adversos , Uretana/efeitos adversos , Feminino , Humanos , Mastectomia/métodos , Período Pós-Operatório , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento
5.
Anticancer Res ; 40(5): 2537-2548, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32366398

RESUMO

BACKGROUND/AIM: Radiotherapy-induced autophagy affects radiation-sensitivity and radiotherapy efficacy. Histone modifications also occur during radiotherapy. This study assessed radiotherapy effects on histone modification and autophagy in non-small cell lung cancer (NSCLC) cells. MATERIALS AND METHODS: NSCLC cells were subjected to γ-irradiation. Autophagy was detected using western blotting and acridine orange staining. Radiation effect on cell growth was evaluated by clonogenic assay. Histone modifications were assessed by western blotting. Next generation sequencings (NGSs) were conducted to identify histone modification target genes. RESULTS: Radio-protective autophagy and histone H4 lysine 20 trimethylation (H4K20me3) were up-regulated after irradiation. By NGSs, genes that are differentially expressed upon irradiation were identified, including the candidate H4K20me3 target gene GABARAPL1. Furthermore, we showed that GABARAPL1 is essential for the radiation-induced autophagy. CONCLUSION: Our findings revealed the regulatory axis of radiation-induced H4K20me3-GABARAPL1 in radio-protective autophagy. Modulation of this axis may be a new strategy to enhance radiotherapy efficacy in NSCLC.


Assuntos
Autofagia/efeitos da radiação , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Lisina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Linhagem Celular Tumoral , Epigênese Genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Metilação , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , RNA Interferente Pequeno/genética
6.
J Chromatogr A ; 1621: 461085, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32376018

RESUMO

Two analytical methodologies based on the combined use of hydroxypropyl-ß-cyclodextrin and two different amino acid-based chiral ionic liquids (tetrabutylammonium-L-lysine or tetrabutylammonium-L-glutamic acid) in electrokinetic chromatography were developed in this work to perform the enantioselective determination of econazole and sulconazole in pharmaceutical formulations. The influence of different experimental variables such as buffer concentration, applied voltage, nature and concentration of the ionic liquid, temperature and injection time, on the enantiomeric separation was investigated. The combination of hydroxypropyl-ß-cyclodextrin and tetrabutylammonium-L-lysine under the optimized conditions enabled to achieve the enantiomeric determination of both drugs with high enantiomeric resolution (3.5 for econazole and 2.4 for sulconazole). The analytical characteristics of the developed methodologies were evaluated in terms of linearity, precision, LOD, LOQ and recovery showing good performance for the determination of both drugs which were successfully quantitated in pharmaceutical formulations. This work reports the first analytical methodology enabling the enantiomeric determination of sulconazole in pharmaceutical formulations.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/química , Cromatografia Capilar Eletrocinética Micelar/métodos , Econazol/análise , Ácido Glutâmico/química , Imidazóis/análise , Líquidos Iônicos/química , Lisina/química , Compostos de Amônio Quaternário , Estereoisomerismo , Temperatura , Fatores de Tempo
7.
J Anim Sci ; 98(5)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32367123

RESUMO

A study was conducted to evaluate the effects of divergent genetic selection for residual feed intake (RFI) on nitrogen (N) metabolism and lysine utilization in growing pigs. Twenty-four gilts (body weight [BW] 66 ± 5 kg) were selected from generation nine of the low RFI (LRFI; n = 12) and high RFI (HRFI; n = 12) Iowa State University Yorkshire RFI selection lines. Six pigs from each genetic line were assigned to each of two levels of lysine intake: 70% and 100% of estimated requirements based on the potential of each genetic line for protein deposition (PD) and feed intake. For all diets, lysine was first limiting among amino acids. Using isotope tracer, N-balance, and nutrient digestibility evaluation approaches, whole-body N metabolism and the efficiency of lysine utilization were determined for each treatment group. No significant interaction effects of line and diet on dietary N or gross energy digestibility, PD, and the efficiency of lysine utilization for PD were observed. The line did not have a significant effect on PD and digestibility of dietary N and GE. An increase in lysine intake improved N retention in both lines (from 15.0 to 19.6 g/d, SE 1.44, in LRFI pigs; and from 16.9 to 19.8 g/d, SE 1.67, in HRFI pigs; P < 0.01). At the low lysine intakes and when lysine clearly limited PD, the efficiency of using available lysine intake (above maintenance requirements) for PD was 80% and 91% (SE 4.6) for the LRFI and HRFI pigs, respectively (P = 0.006). There were no significant effects of line or of the line by diet interaction on N flux, protein synthesis, and protein degradation. Lysine intake significantly increased (P < 0.05) N flux (from 119 to 150, SE 8.7 g/d), protein synthesis (from 99 to 117, SE 10.6 g of N/d), and protein degradation (from 85 to 100, SE 6.6 g of N/d). The protein synthesis-to-retention ratio tended to be higher in the LRFI line compared with the HRFI line (6.5 vs. 5.8 SE 0.62; P = 0.06), indicating a tendency for the lower efficiency of PD in this group. Collectively, these results indicate that genetic selection for low RFI is not associated with improvements in lysine utilization efficiency, protein turnover, and nutrient digestibility.


Assuntos
Dieta/veterinária , Comportamento Alimentar/fisiologia , Lisina/metabolismo , Nitrogênio/metabolismo , Suínos/genética , Ração Animal/análise , Animais , Peso Corporal , Ingestão de Alimentos/fisiologia , Metabolismo Energético/genética , Metabolismo Energético/fisiologia , Feminino , Lisina/administração & dosagem , Suínos/crescimento & desenvolvimento , Suínos/metabolismo
8.
BMC Bioinformatics ; 21(Suppl 3): 63, 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32321437

RESUMO

BACKGROUND: Protein succinylation has recently emerged as an important and common post-translation modification (PTM) that occurs on lysine residues. Succinylation is notable both in its size (e.g., at 100 Da, it is one of the larger chemical PTMs) and in its ability to modify the net charge of the modified lysine residue from + 1 to - 1 at physiological pH. The gross local changes that occur in proteins upon succinylation have been shown to correspond with changes in gene activity and to be perturbed by defects in the citric acid cycle. These observations, together with the fact that succinate is generated as a metabolic intermediate during cellular respiration, have led to suggestions that protein succinylation may play a role in the interaction between cellular metabolism and important cellular functions. For instance, succinylation likely represents an important aspect of genomic regulation and repair and may have important consequences in the etiology of a number of disease states. In this study, we developed DeepSuccinylSite, a novel prediction tool that uses deep learning methodology along with embedding to identify succinylation sites in proteins based on their primary structure. RESULTS: Using an independent test set of experimentally identified succinylation sites, our method achieved efficiency scores of 79%, 68.7% and 0.48 for sensitivity, specificity and MCC respectively, with an area under the receiver operator characteristic (ROC) curve of 0.8. In side-by-side comparisons with previously described succinylation predictors, DeepSuccinylSite represents a significant improvement in overall accuracy for prediction of succinylation sites. CONCLUSION: Together, these results suggest that our method represents a robust and complementary technique for advanced exploration of protein succinylation.


Assuntos
Aprendizado Profundo , Processamento de Proteína Pós-Traducional , Proteínas/metabolismo , Succinatos/metabolismo , Sítios de Ligação , Ciclo do Ácido Cítrico , Lisina/metabolismo , Proteínas/química
9.
Gene ; 745: 144647, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32247738

RESUMO

AIMS: Post-translational modifications (PTMs) of histones are regulated by the availability of their respective acyl-CoAs. Among these histone PTMs, the metabolic origin of histone butyrylation (Kbu) is still poorly understood. MATERIAL AND METHODS: The impact of starvation on the levels of Kbu was determined by western blotting on histones extracted from the liver of fed and fasted C57BL/6 mice and immunohistochemistry on liver paraffin sections. KEY FINDINGS: Using animal model we provide evidence that the stimulation of ketogenesis following starvation, in addition to histone beta-hydroxybutyrylation (Kbhb), also leads to an increase in histone butyrylation (Kbu). Using an immunohistochemistry (IHC) approach we report first that hepatocytes contained butyrylated histones with important cell-to-cell heterogeneity. More importantly, our investigations based on western blotting and IHC also proposed that the basal levels of Kbu differ between male and female mice, with female mouse hepatocytes containing higher levels of butyrylated histones. Starvation enhanced solely histone Kbu levels in the liver of males but not females. SIGNIFICANCE: This is the first demonstration of a sex-dependent large-scale stimulation of histone acylation. Our data also point to different basal metabolic conditions of the male and female liver cells with a sex-dependent impact on the hepatocytes' epigenome.


Assuntos
Histonas/metabolismo , Fígado/patologia , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Inanição/patologia , Ácido 3-Hidroxibutírico/metabolismo , Acil Coenzima A/metabolismo , Acilação , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Hepatócitos/patologia , Código das Histonas , Humanos , Corpos Cetônicos/metabolismo , Fígado/citologia , Masculino , Camundongos , Fatores Sexuais
10.
Biochem Biophys Res Commun ; 526(4): 947-952, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32291076

RESUMO

The outbreak of corona virus disease 2019 (COVID-19) caused by SARS-CoV-2 infection is spreading globally and quickly, leading to emerging health issues. SARS-CoV-2 enters into and infects host cells through its spike glycoprotein recognizing the cell receptor Angiotensin-converting enzyme II (ACE2). Here, we noticed that ACE2 was further enhanced by SARS-CoV-2 infection. Human germ cells and early embryos express high level of ACE2. Notably, RNA-seq result showed that reduction of H3K27me3, but not H3K4/9/36me3, led to upregulation of Ace2 expression in mouse germ cell line GC-2. In agreement with this result, we found in human embryonic stem cells that ACE2 expression was significantly increased in absence of EZH2, the major enzyme catalyzing H3K27me3. ChIP-seq analysis further confirmed decrease of H3K27me3 signal and increase of H3K27ac signal at ACE2 promoter upon EZH2 knockout. Therefore, we propose that EZH2-mediated H3K27me3 at ACE2 promoter region inhibits ACE2 expression in mammalian cells. This regulatory pattern may also exist in other human cells and tissues. Our discovery provides clues for pathogenesis and targeted drug therapy towards ACE2 expression for prevention and adjuvant therapy of COVID-19.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epigênese Genética , Regulação da Expressão Gênica , Peptidil Dipeptidase A/genética , Pneumonia Viral/virologia , Animais , Células-Tronco Embrionárias , Técnicas de Inativação de Genes , Código das Histonas , Histonas/química , Histonas/metabolismo , Humanos , Lisina/análise , Lisina/metabolismo , Metilação , Camundongos , Especificidade de Órgãos , Pandemias , Regiões Promotoras Genéticas , Transcrição Genética , Regulação para Cima
11.
PLoS One ; 15(4): e0230930, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267870

RESUMO

Human epidemiological studies have shown that paternal aging as one of the risk factors for neurodevelopmental disorders, such as autism, in offspring. A recent study has suggested that factors other than de novo mutations due to aging can influence the biology of offspring. Here, we focused on epigenetic alterations in sperm that can influence developmental programs in offspring. In this study, we qualitatively and semiquantitatively evaluated histone modification patterns in male germline cells throughout spermatogenesis based on immunostaining of testes taken from young (3 months old) and aged (12 months old) mice. Although localization patterns were not obviously changed between young and aged testes, some histone modification showed differences in their intensity. Among histone modifications that repress gene expression, histone H3 lysine 9 trimethylation (H3K9me3) was decreased in the male germline cells of the aged testis, while H3K27me2/3 was increased. The intensity of H3K27 acetylation (ac), an active mark, was lower/higher depending on the stages in the aged testis. Interestingly, H3K27ac was detected on the putative sex chromosomes of round spermatids, while other chromosomes were occupied by a repressive mark, H3K27me3. Among other histone modifications that activate gene expression, H3K4me2 was drastically decreased in the male germline cells of the aged testis. In contrast, H3K79me3 was increased in M-phase spermatocytes, where it accumulates on the sex chromosomes. Therefore, aging induced alterations in the amount of histone modifications and in the differences of patterns for each modification. Moreover, histone modifications on the sex chromosomes and on other chromosomes seems to be differentially regulated by aging. These findings will help elucidate the epigenetic mechanisms underlying the influence of paternal aging on offspring development.


Assuntos
Histonas/genética , Meiose/genética , Espermatócitos/fisiologia , Espermatogênese/genética , Testículo/fisiologia , Acetilação , Animais , Epigênese Genética/genética , Epigenômica/métodos , Expressão Gênica/genética , Código das Histonas/genética , Humanos , Lisina/genética , Masculino , Metilação , Camundongos , Processamento de Proteína Pós-Traducional/genética , Cromossomos Sexuais/genética , Espermátides/fisiologia
12.
PLoS Biol ; 18(4): e3000684, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32275660

RESUMO

5-hydroxymethylcytosine (5hmC) is the most prevalent intermediate on the oxidative DNA demethylation pathway and is implicated in regulation of embryogenesis, neurological processes, and cancerogenesis. Profiling of this relatively scarce genomic modification in clinical samples requires cost-effective high-resolution techniques that avoid harsh chemical treatment. Here, we present a bisulfite-free approach for 5hmC profiling at single-nucleotide resolution, named hmTOP-seq (5hmC-specific tethered oligonucleotide-primed sequencing), which is based on direct sequence readout primed at covalently labeled 5hmC sites from an in situ tethered DNA oligonucleotide. Examination of distinct conjugation chemistries suggested a structural model for the tether-directed nonhomologous polymerase priming enabling theoretical evaluation of suitable tethers at the design stage. The hmTOP-seq procedure was optimized and validated on a small model genome and mouse embryonic stem cells, which allowed construction of single-nucleotide 5hmC maps reflecting subtle differences in strand-specific CG hydroxymethylation. Collectively, hmTOP-seq provides a new valuable tool for cost-effective and precise identification of 5hmC in characterizing its biological role and epigenetic changes associated with human disease.


Assuntos
5-Metilcitosina/análogos & derivados , Análise de Sequência de DNA/métodos , 5-Metilcitosina/química , Acetilação , Animais , Bacteriófago lambda/genética , Linhagem Celular , Metilação de DNA , Células-Tronco Embrionárias/fisiologia , Genoma , Histonas/metabolismo , Lisina/metabolismo , Camundongos , Oligonucleotídeos , Reprodutibilidade dos Testes , Sulfitos
13.
Arch Biochem Biophys ; 686: 108373, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32325089

RESUMO

Non-enzymatic protein glycation results in the formation of advanced glycation end products (AGEs) leads to the pathogenesis of long-term diabetic complications. Iridin (ID), an antioxidant, plays an important role in protecting against oxidative stress and could therefore be an efficacious anti-glycating regimen. Herein, we assessed the anti-glycating potential of ID against d-ribose induced glycation of bovine serum albumin (BSA) by various biophysical and biochemical techniques. Our results from several physicochemical assays advocated that ID was able to evidently prevent the AGEs generation via reducing hyperchromicity, early glycation products (EGPs), carbonyl content (CC), hydroxymethyl furfural (HMF) content, production of fluorescent AGEs, protection against loss of secondary structure (i.e. α-helix and ß-sheets) of proteins, increasing the free lysine and free arginine content, reduced binding of congo red (CR), and reduced thioflavin T (ThT) and 8-aninilo-1-napthalene sulphonate (ANS)-specific fuorescence in glycated-BSA (Gly-BSA). On the basis of these findings, we concluded that ID possesses the significant anti-glycation potential and may be established as a remarkable anti-AGEs therapeutic agent. Further in-vivo and clinical studies are still warranted to uncover the therapeutic effects of ID against age-related as well as metabolic diseases.


Assuntos
Antioxidantes/química , Protaminas/química , Ribose/química , Soroalbumina Bovina/química , Arginina/química , Benzotiazóis/química , Sítios de Ligação , Corantes Fluorescentes/química , Produtos Finais de Glicação Avançada/química , Glicosilação , Lisina/química , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Ligação Proteica , Estrutura Secundária de Proteína
14.
Nat Commun ; 11(1): 1813, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286279

RESUMO

The oocyte cytoplasm can reprogram the somatic cell nucleus into a totipotent state, but with low efficiency. The spatiotemporal chromatin organization of somatic cell nuclear transfer (SCNT) embryos remains elusive. Here, we examine higher order chromatin structures of mouse SCNT embryos using a low-input Hi-C method. We find that donor cell chromatin transforms to the metaphase state rapidly after SCNT along with the dissolution of typical 3D chromatin structure. Intriguingly, the genome undergoes a mitotic metaphase-like to meiosis metaphase II-like transition following activation. Subsequently, weak chromatin compartments and topologically associating domains (TADs) emerge following metaphase exit. TADs are further removed until the 2-cell stage before being progressively reestablished. Obvious defects including stronger TAD boundaries, aberrant super-enhancer and promoter interactions are found in SCNT embryos. These defects are partially caused by inherited H3K9me3, and can be rescued by Kdm4d overexpression. These observations provide insight into chromatin architecture reorganization during SCNT embryo development.


Assuntos
Cromatina/metabolismo , Embrião de Mamíferos/metabolismo , Técnicas de Transferência Nuclear , Animais , Reprogramação Celular , Desenvolvimento Embrionário , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica no Desenvolvimento , Genoma , Histonas/metabolismo , Lisina/metabolismo , Metáfase , Metilação , Camundongos , Regiões Promotoras Genéticas/genética , Zigoto/metabolismo
15.
Nat Genet ; 52(3): 273-282, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32139906

RESUMO

Mutations in enzymes that modify histone H3 at lysine 4 (H3K4) or lysine 36 (H3K36) have been linked to human disease, yet the role of these residues in mammals is unclear. We mutated K4 or K36 to alanine in the histone variant H3.3 and showed that the K4A mutation in mouse embryonic stem cells (ESCs) impaired differentiation and induced widespread gene expression changes. K4A resulted in substantial H3.3 depletion, especially at ESC promoters; it was accompanied by reduced remodeler binding and increased RNA polymerase II (Pol II) activity. Regulatory regions depleted of H3.3K4A showed histone modification alterations and changes in enhancer activity that correlated with gene expression. In contrast, the K36A mutation did not alter H3.3 deposition and affected gene expression at the later stages of differentiation. Thus, H3K4 is required for nucleosome deposition, histone turnover and chromatin remodeler binding at regulatory regions, where tight regulation of Pol II activity is necessary for proper ESC differentiation.


Assuntos
Diferenciação Celular/genética , Montagem e Desmontagem da Cromatina/genética , Código das Histonas/genética , Histonas/genética , Lisina/metabolismo , Sequências Reguladoras de Ácido Nucleico/genética , Alanina/metabolismo , Animais , Elementos Facilitadores Genéticos/genética , Células HEK293 , Humanos , Camundongos , Células-Tronco Embrionárias Murinas , Mutação , Nucleossomos/metabolismo , Regiões Promotoras Genéticas/genética , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Transcrição Genética
16.
Emerg Microbes Infect ; 9(1): 714-726, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32196427

RESUMO

Tick-borne encephalitis virus (TBEV) accounts for approximately 10,000 annual cases of severe encephalitis in Europe and Asia and causes encephalitis in humans. In this study, we demonstrate TBEV appears to activate the interferon (IFN)-ß dependent on RIG-I/MDA5. Both the IFN-ß accumulation and the IFN stimulated genes (ISGs) transcription greatly delay. Further studies reveal that TBEV NS4A could block the phosphorylation and dimerization of STAT1/STAT2 to affect type I and II IFN-mediated STAT signalling. Additional data indicate that the residue at K132 of TBEV NS4A could be modified by ubiquitination and this modification is necessary for the interaction of NS4A with STAT1. Dynamic ubiquitination of the NS4 protein during TBEV infection might account for delayed activation of the ISGs. These results define the TBEV NS4A as an antagonist of the IFN response, by demonstrating a correlation between the association and STAT interference. Our findings provide a foundation for further understanding how TBEV evade innate immunity and a potential viral target for intervention.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Interferon Tipo I/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo , Linhagem Celular , Proteína DEAD-box 58/metabolismo , Vírus da Encefalite Transmitidos por Carrapatos/metabolismo , Humanos , Fatores Reguladores de Interferon/antagonistas & inibidores , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Interferon Tipo I/metabolismo , Helicase IFIH1 Induzida por Interferon/metabolismo , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Interferon beta/genética , Interferon beta/metabolismo , Lisina/metabolismo , Fosforilação , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT2/metabolismo , Transdução de Sinais , Ubiquitinação , Regulação para Cima , Domínios de Homologia de src
17.
Sheng Wu Gong Cheng Xue Bao ; 36(2): 226-240, 2020 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-32147995

RESUMO

As a member of the histone lysine-specific demethylase family, KDM1A plays a pivotal role in biological processes including signal transduction, chromatin reprogramming, embryo development, hematopoiesis, glucose and lipid metabolism. Recently, increasing studies and clinical evidences suggest that the expression of KDM1A is related to initiation and development of tumors and plays a key role in regulating of initiation and development of tumors, such as prostate cancer, breast cancer, lung cancer and liver cancer. KDM1A binds to distinct complexes and mediates different downstream signaling pathways. However, KDM1A often plays an oncogenic role in the initiation and development of tumors. Based on the current literatures, we describe the latest research of KDM1A in the initiation and progression of various tumors, and summarize its mechanism of actions, to provide clues for cancer therapy.


Assuntos
Carcinogênese , Transformação Celular Neoplásica , Histona Desmetilases , Histonas , Humanos , Lisina , Oncogenes
18.
Nat Commun ; 11(1): 1132, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32111831

RESUMO

The promising drug target N-myristoyltransferase (NMT) catalyses an essential protein modification thought to occur exclusively at N-terminal glycines (Gly). Here, we present high-resolution human NMT1 structures co-crystallised with reactive cognate lipid and peptide substrates, revealing high-resolution snapshots of the entire catalytic mechanism from the initial to final reaction states. Structural comparisons, together with biochemical analysis, provide unforeseen details about how NMT1 reaches a catalytically competent conformation in which the reactive groups are brought into close proximity to enable catalysis. We demonstrate that this mechanism further supports efficient and unprecedented myristoylation of an N-terminal lysine side chain, providing evidence that NMT acts both as N-terminal-lysine and glycine myristoyltransferase.


Assuntos
Aciltransferases/química , Aciltransferases/metabolismo , Glicina/metabolismo , Lisina/metabolismo , Aciltransferases/genética , Catálise , Domínio Catalítico , Coenzima A/química , Coenzima A/genética , Coenzima A/metabolismo , Cristalografia por Raios X , Humanos , Cinética , Mutação , Ácido Mirístico/metabolismo , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Especificidade por Substrato
19.
Int J Nanomedicine ; 15: 1457-1468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184598

RESUMO

Purpose: Zinc oxide nanoparticles (nZnO) have been widely used in the medicine field. Numerous mechanistic studies for nZnO's anticancer effects are merely performed under high concentration exposure. However, possible anticancer mechanisms of epigenetic dysregulation induced by low doses of nZnO are unclear. Methods: nZnO were characterized and bladder cancer T24 cells were treated with nZnO for 48 hrs at different exposure concentrations. Cell cycle, apoptosis, cell migration and invasion were determined. We performed qRT-PCR, Western blot and chromatin immunoprecipitation to detect the mRNA and protein levels of signaling pathway cascades for histone modification. Results: In this study, we investigated the potential anticancer effects and mechanisms of nZnO on histone modifications in bladder cancer T24 cells upon low-dose exposure. Our findings showed that low concentrations of nZnO resulted in cell cycle arrest at S phase, facilitated cellular late apoptosis, repressed cell invasion and migration after 48 hrs exposure. These anticancer effects could be attributed to increased RUNX3 levels resulting from reduced H3K27me3 occupancy on the RUNX3 promoter, as well as decreased contents of histone methyltransferase EZH2 and the trimethylation of histone H3K27. Our findings reveal that nZnO are able to enter into the cytoplasm and nucleus of T24 cells. Additionally, both particles and ions from nZnO may jointly contribute to the alteration of histone methylation. Moreover, sublethal nZnO-conducted anticancer effects and epigenetic mechanisms were not associated with oxidative stress or DNA damage. Conclusion: We reveal a novel epigenetic mechanism for anticancer effects of nZnO in bladder cancer cells under low-dose exposure. This study will provide experimental basis for the toxicology and cancer therapy of nanomaterials.


Assuntos
Antineoplásicos/farmacologia , Metilação de DNA/efeitos dos fármacos , Histonas/metabolismo , Nanopartículas Metálicas/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Óxido de Zinco/farmacologia , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Relação Dose-Resposta a Droga , Epigênese Genética/efeitos dos fármacos , Humanos , Lisina/metabolismo , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Estresse Oxidativo/efeitos dos fármacos , Regiões Promotoras Genéticas , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Óxido de Zinco/administração & dosagem
20.
Nat Commun ; 11(1): 1146, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32123171

RESUMO

Linear ubiquitination is a critical regulator of inflammatory signaling pathways. However, linearly ubiquitinated substrates and the biological significance of linear ubiquitination is incompletely understood. Here, we show that STAT1 has linear ubiquitination at Lys511 and Lys652 residues in intact cells, which inhibits STAT1 binding to the type-I interferon receptor IFNAR2, thereby restricting STAT1 activation and resulting in type-I interferon signaling homeostasis. Linear ubiquitination of STAT1 is removed rapidly by OTULIN upon type-I interferon stimulation, which facilitates activation of interferon-STAT1 signaling. Furthermore, viruses induce HOIP expression through the NF-κB pathway, which in turn increases linear ubiquitination of STAT1 and thereby inhibits interferon antiviral response. Consequently, HOIL-1L heterozygous mice have active STAT1 signaling and enhanced responses to type-I interferons. These findings demonstrate a linear ubiquitination-mediated switch between homeostasis and activation of type-I interferon signaling, and suggest potential strategies for clinical antiviral therapy.


Assuntos
Interferon Tipo I/metabolismo , Fator de Transcrição STAT1/metabolismo , Animais , Linhagem Celular , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Interferon Tipo I/farmacologia , Lisina/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Receptor de Interferon alfa e beta/metabolismo , Fator de Transcrição STAT1/genética , Transdução de Sinais/efeitos dos fármacos , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
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