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1.
Toxicol Lett ; 316: 147-153, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31520700

RESUMO

Asthma is a common chronic inflammatory disease which severely reduces the quality of life in patients. Studies have demonstrated that both PM2.5 and cold stress contribute to the development of asthma. However, the combined effects of these two risking factors are unknown. In this study, we investigated the combined effects of PM2.5 exposure and cold stress (PMCS) on asthma, as well as the underlying mechanisms by using a murine model. After different exposures, the immune-pathological changes and redox states in groups were evaluated. Besides, the balance of TH1/TH2 cells and the acetylation levels of H3K9 and H3K14 in IL-4 gene promotor were detected. Our results showed that, compared with other exposures, PMCS led to an increased inflammation and redox levels in mice. It also significantly increased the percentage of TH2 T cells, which was correlated with hyperacetylation of H3K9 and H3K14 in IL-4 gene promoter in CD4+T cells. Furthermore, a significantly increased P300 and decreased HDAC1 were detected in CD4 + T cells in PMCS group. In conclusion, our findings demonstrated that PMCS exacerbated asthma in mice by increasing H3K9 and H3K14 acetylation in IL-4 gene promoter in CD4 + T cells, and P300 and HDAC1 might contribute to their combined effects.


Assuntos
Asma/induzido quimicamente , Temperatura Baixa/efeitos adversos , Histonas/metabolismo , Interleucina-4/metabolismo , Pulmão/efeitos dos fármacos , Material Particulado/toxicidade , Regiões Promotoras Genéticas , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Acetilação , Animais , Asma/genética , Asma/imunologia , Asma/metabolismo , Modelos Animais de Doenças , Proteína p300 Associada a E1A/metabolismo , Histona Desacetilase 1/metabolismo , Interleucina-4/genética , Interleucina-4/imunologia , Pulmão/imunologia , Pulmão/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Ovalbumina , Tamanho da Partícula , Processamento de Proteína Pós-Traducional , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo
2.
Adv Exp Med Biol ; 1158: 59-70, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31452135

RESUMO

Mitochondria have a central role in cellular metabolism and reversible post-translational modifications regulate activity of mitochondrial proteins. Thanks to advances in proteomics, lysine acetylation has arisen as an important post-translational modification in the mitochondrion. During acetylation an acetyl group is covalently attached to the epsilon amino group in the side chain of lysine residues using acetyl-CoA as the substrate donor. Therefore the positive charge is neutralized, and this can affect the function of proteins thereby regulating enzyme activity, protein interactions, and protein stability. The major deacetylase in mitochondria is SIRT3 whose activity regulates many mitochondrial enzymes. The method of choice for the analysis of acetylated proteins foresees the combination of mass spectrometry-based proteomics with affinity enrichment techniques. Beyond the identification of lysine-acetylated proteins, many studies are moving towards the characterization of acetylated patterns in different diseases. Indeed, modifications in lysine acetylation status can directly alter mitochondrial function and, therefore, be linked to human diseases such as metabolic diseases, cancer, myocardial injury and neurodegenerative diseases. Despite the progress in the characterization of different lysine acetylation sites, additional studies are needed to differentiate the specific changes with a significant biological relevance.


Assuntos
Lisina , Mitocôndrias , Fenótipo , Acetilação , Humanos , Lisina/metabolismo , Mitocôndrias/química , Mitocôndrias/metabolismo , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , Processamento de Proteína Pós-Traducional
3.
Anticancer Res ; 39(8): 4199-4206, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366506

RESUMO

BACKGROUND/AIM: We previously synthesized a glucose-conjugated chlorin compound e6 (G-chlorin e6), and reported that it has very strong antitumor effects. The aim of the present study was to synthesize acetylated glucose-conjugated chlorin (AcN003HP) and evaluate its antitumor effect and excretion. MATERIALS AND METHODS: To evaluate the antitumor effect of AcN003HP, its IC50 was calculated as well as its accumulation in cancer cells was examined by flow cytometry. Confocal microscopy was used to observe the intracellular localization of AcN003HP. The excretion and antitumor effects of AcN003HP were also evaluated in vivo. RESULTS: AcN003HP showed stronger antitumor effects and accumulation into cancer cells compared to talaporfin sodium, a conventional photosensitizer. AcN003HP was localized in the endoplasmic reticulum. In a xenograft tumor mouse model, AcN003HP showed longer excretion time from the body than G-chlorin e6, and photodynamic therapy using AcN003HP showed very strong antitumor effects. CONCLUSION: The safety, improved controllability, and robust antitumor effects suggest AcN003HP as a good next-generation photosensitizer.


Assuntos
Neoplasias Gastrointestinais/terapia , Glucose/administração & dosagem , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Acetilação/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Retículo Endoplasmático/efeitos dos fármacos , Citometria de Fluxo , Neoplasias Gastrointestinais/patologia , Glucose/síntese química , Glucose/química , Humanos , Camundongos , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Porfirinas/administração & dosagem , Porfirinas/síntese química , Porfirinas/química , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Results Probl Cell Differ ; 67: 17-25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31435790

RESUMO

Acetylation is among the most prevalent posttranslational modifications in cells and regulates a number of physiological processes such as gene transcription, cell metabolism, and cell signaling. Although initially discovered on nuclear histones, many non-nuclear proteins have subsequently been found to be acetylated as well. The centrosome is the major microtubule-organizing center in most metazoans. Recent proteomic data indicate that a number of proteins in this subcellular compartment are acetylated. This review gives an overview of our current knowledge on protein acetylation at the centrosome and its functional relevance in organelle biology.


Assuntos
Centrossomo/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas/metabolismo , Acetilação , Animais , Histonas/metabolismo , Humanos , Proteômica
5.
Georgian Med News ; (291): 93-97, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31418739

RESUMO

The article solves a current task concerning a substantiated use of acetylation phenotype as susceptibility biomarker to unfavourable effect of chemical substances in scientific studies. Objective: to study a combined effect of sodium nitrate and cadmium chloride on the prooxidant-antioxidant balance of the blood, liver and functional state of the central nervous system in young rats with different acetylation type. The experimental studies were performed on immature male rats 1,5-month of age. The experimental animals were divided into two groups according to the amount of general sulfadimine excreted with urine: "rapid" and "slow" acetylators. 2 subgroups were differentiated in every group: I - control animals, II - animals subjected to administration of cadmium chloride and sodium nitrate. Administration of sodium nitrate and cadmium chloride to animals in the doses 1/15 DL50 and 1/150 DL50 respectively during 14 days found that at the young age "slow" acetylation type is susceptibility marker, and the criteria of a harmful effect in them are the following: 25% increase protein peroxide oxidation in the blood plasma, 34% and 30% increase of average molecular peptides and ceruloplasmin respectively, and 6,7 times increase of methemoglobin (hemiglobin) concentration. Nitrate-cadmium intoxication caused inhibition of the integral behavioural activity both in slow and rapid acetylators. Disturbed behavioural activity in young animals with "slow" acetylation type under conditions of subacute effect of sodium nitrate and cadmium chloride is caused mainly by an increased content of liver lipoperoxidation secondary products and less - by the levels of average molecular peptides and ceruloplasmin in the blood plasma, and in "rapid" acetylators - by increased products of oxidation-modification proteins.


Assuntos
Acetilação/efeitos dos fármacos , Cádmio/toxicidade , Nitratos/toxicidade , Animais , Biomarcadores/metabolismo , Intoxicação por Cádmio/metabolismo , Masculino , Fenótipo , Ratos
6.
Genes Dev ; 33(17-18): 1280-1292, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31371438

RESUMO

All cells use proteases to adjust protein amounts. Proteases maintain protein homeostasis by degrading nonfunctional toxic proteins and play regulatory roles by targeting particular substrates in response to specific signals. Here we address how cells tune protease specificity to nutritional signals. We report that Salmonella enterica increases the specificity of the broadly conserved proteases Lon and ClpSAP by transforming the Lon activator and substrate HspQ into an inhibitor of the N-degron recognin ClpS, the adaptor of the ClpAP protease. We establish that upon acetylation, HspQ stops being a Lon activator and substrate and that the accumulated HspQ binds to ClpS, hindering degradation of ClpSAP substrates. Growth on glucose promotes HspQ acetylation by increasing acetyl-CoA amounts, thereby linking metabolism to proteolysis. By altering protease specificities but continuing to degrade junk proteins, cells modify the abundance of particular proteins while preserving the quality of their proteomes. This rapid response mechanism linking protease specificity to nutritional signals is broadly conserved.


Assuntos
Proteínas de Bactérias/metabolismo , Fenômenos Fisiológicos da Nutrição , Salmonella enterica/enzimologia , Acetilação , Ativadores de Enzimas/metabolismo , Inibidores Enzimáticos/metabolismo , Glucose/metabolismo , Proteínas de Choque Térmico , Protease La/metabolismo , Ligação Proteica , Proteólise , Salmonella enterica/crescimento & desenvolvimento , Especificidade por Substrato
7.
BMC Vet Res ; 15(1): 267, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31357995

RESUMO

BACKGROUND: In practical production, dairy cows are frequently exposed to bacterial endotoxin (lipopolysaccharide, LPS) when they are subjected to high-concentrate diets, poor hygienic environments, as well as mastitis and metritis. Histone acetylation is an important epigenetic control of DNA transcription and a higher histone acetylation is associated with facilitated transcription. LPS might reduce histone acetylation in the mammary epithelial cells, resulting in lower transcription and mRNA expression of lactation-related genes. This study was conducted to investigate the effect of LPS on histone acetylation in bovine mammary epithelial cells and the efficacy of sodium butyrate (SB) in suppressing the endotoxin-induced adverse effect. Firstly, the bovine mammary epithelial cell line MAC-T cells were treated for 48 h with LPS at different doses of 0, 1, 10, 100, and 1000 endotoxin units (EU)/mL (1 EU = 0.1 ng), and the acetylation levels of histones H3 and H4 as well as the histone deacetylase (HDAC) activity were measured. Secondly, the MAC-T cells were treated for 48 h as follows: control, LPS (100 EU/mL), and LPS (100 EU/mL) plus SB (10 mmol/L), and the acetylation levels of histones H3 and H4 as well as milk gene mRNA expressions were determined. RESULTS: The results showed that HDAC activity increased linearly with increasing LPS doses (P < 0.01). The histone H3 acetylation levels were significantly reduced by LPS, while the histone H4 acetylation levels were not affected by LPS (P > 0.05). Sodium butyrate, an inhibitor of HDAC, effectively suppressed the endotoxin-induced decline of histone H3 acetylation (P < 0.05). As a result, SB significantly enhanced the mRNA expression of lactation-related genes (P < 0.05). CONCLUSIONS: The results suggest one of the adverse effects of LPS on the lactation of bovine mammary gland epithelial cells was due to decreasing histone H3 acetylation through increasing HDAC activity, whereas the endotoxin-induced adverse effects were effectively suppressed by SB.


Assuntos
Ácido Butírico/farmacologia , Endotoxinas/toxicidade , Células Epiteliais/efeitos dos fármacos , Histonas/metabolismo , Glândulas Mamárias Animais/efeitos dos fármacos , Acetilação/efeitos dos fármacos , Animais , Bovinos , Feminino , Antagonistas dos Receptores Histamínicos/farmacologia , Glândulas Mamárias Animais/citologia
8.
J Agric Food Chem ; 67(33): 9344-9353, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31361957

RESUMO

Anthocyanins determine the color and potential health-promoting properties of red fruit juices, but the juices contain remarkably less anthocyanins than the fruits, which is partly caused by the interactions of anthocyanins with the residues of cell wall polysaccharides like pectin. In this study, pectin was modified by ultrasound and enzyme treatments to residues of polysaccharides and oligosaccharides widely differing in their molecular weight. Modifications decreased viscosity and degrees of acetylation and methylation and released smooth and hairy region fragments. Native and modified pectin induced different effects on the concentrations of individual anthocyanins after short-term and long-term incubation caused by both hydrophobic and hydrophilic interactions. Results indicate that both pectin and anthocyanin structure influence these interactions. Linear polymers generated by ultrasound formed insoluble anthocyanin complexes, whereas oligosaccharides produced by enzymes formed soluble complexes with protective properties. The structure of the anthocyanin aglycone apparently influenced interactions more than the sugar moiety.


Assuntos
Antocianinas/química , Beta vulgaris/química , Pectinas/química , Acetilação , Cor , Frutas/química , Sucos de Frutas e Vegetais/análise , Interações Hidrofóbicas e Hidrofílicas , Metilação , Peso Molecular , Ultrassom , Viscosidade
9.
J Agric Food Chem ; 67(31): 8700-8705, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31294561

RESUMO

This study reported a new headspace gas chromatography (HS-GC) for simultaneously determining the degree of deacetylation (DD) and the degree of substitution (DS) in carboxymethyl chitosan (CMCS), which were based on HS-GC measuring the amounts of CO2 released from both the bicarbonate decomposition suppressed by -NH2 and the reaction between the bicarbonate and the acidified carboxymethyl and amino groups in CMCS. The results showed that the present method has a good measurement precision (RSD < 2.55%) and accuracy (relative differences <5.90%). Compared with the current titration-based method, the present HS-GC techniques provide a more reliable testing in the quantification of amino and carboxymethyl contents in CMCS. Moreover, since the HS-GC can perform an automated sample reaction equilibration and measurement, it could be much more efficient than the existing methods in the batch sample analysis.


Assuntos
Quitosana/análogos & derivados , Cromatografia Gasosa/métodos , Acetilação , Quitosana/química
10.
Adv Exp Med Biol ; 1140: 199-224, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31347049

RESUMO

There are only 30,000 human genes, which, according to the central dogma from biology, it means that there should be 30,000 mRNA and 30,000 proteins. However, there are at least 1-2 million protein entities that are expressed in a cell at a given time. This is primarily due to alternative splicing in different cells and tissues, which may lead to expression of different protein isoforms within one cell, but also different protein isoforms in different tissues. A new level of complexity of proteins and protein isoforms is then given by posttranslational modifications (PTMs) of proteins. Here, we discuss the PTMs in proteins and how they are identified by mass spectrometry and proteomics, with specific examples on identification of acetylation, phosphorylation, glycosylation, alkylation, hydroxinonenal-modification or assignment of intramolecular and intermolecular disulfide bridges.


Assuntos
Espectrometria de Massas , Processamento de Proteína Pós-Traducional , Proteômica , Acetilação , Alquilação , Glicosilação , Humanos , Fosforilação
11.
Toxicol Lett ; 314: 63-74, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31306741

RESUMO

This study aimed to verify the toxic effects of prenatal caffeine exposure (PCE) on the podocyte development in male offspring, and to explore the underlying intrauterine programming mechanisms. The pregnant rats were administered with caffeine (30 to 120 mg/kg⋅d) during gestational day (GD) 9 to 20. The male fetus on GD20 and the offspring at postnatal week (PW) 6 and PW28 were sacrificed. The results indicated that PCE caused ultrastructural abnormalities on podocyte, and inhibited the expression of podocyte marker genes such as Nephrin, Wilms tumor 1 (WT1), the histone 3 lysine 9 acetylation (H3K9ac) level in the Kruppel-like factor 4 (KLF4) promoter and its expression in the male offspring from GD20 to PW28. Meanwhile, the expression of glucocorticoid receptor (GR) and histone deacetylase 7 (HDAC7) in the fetus were increased by PCE. In vitro, corticosterone increased GR and HDAC7 whereas reduced the H3K9ac level of KLF4 and KLF4/Nephrin expression. KLF4 over-expression reversed the reduction of Nephrin expression, knockdown of HDAC7 and GR antagonist RU486 partially reversed the inhibitory effects of corticosterone on H3K9ac level and KLF4 expression. In conclusion, PCE caused podocyte developmental toxicity in male offspring, which was associated with corticosterone-induced low-functional programming of KLF4 through GR/HDAC7/H3K9ac pathway.


Assuntos
Cafeína/toxicidade , Estimulantes do Sistema Nervoso Central/toxicidade , Histonas/metabolismo , Nefropatias/induzido quimicamente , Fatores de Transcrição Kruppel-Like/metabolismo , Podócitos/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Acetilação , Animais , Células Cultivadas , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Idade Gestacional , Glucocorticoides/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Nefropatias/embriologia , Nefropatias/genética , Nefropatias/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Lisina , Masculino , Exposição Materna , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Fenótipo , Podócitos/metabolismo , Podócitos/ultraestrutura , Gravidez , Regiões Promotoras Genéticas , Ratos Wistar , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Transdução de Sinais/efeitos dos fármacos
12.
Nat Commun ; 10(1): 3004, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31285436

RESUMO

Identity determining transcription factors (TFs), or core regulatory (CR) TFs, are governed by cell-type specific super enhancers (SEs). Drugs to selectively inhibit CR circuitry are of high interest for cancer treatment. In alveolar rhabdomyosarcoma, PAX3-FOXO1 activates SEs to induce the expression of other CR TFs, providing a model system for studying cancer cell addiction to CR transcription. Using chemical genetics, the systematic screening of chemical matter for a biological outcome, here we report on a screen for epigenetic chemical probes able to distinguish between SE-driven transcription and constitutive transcription. We find that chemical probes along the acetylation-axis, and not the methylation-axis, selectively disrupt CR transcription. Additionally, we find that histone deacetylases (HDACs) are essential for CR TF transcription. We further dissect the contribution of HDAC isoforms using selective inhibitors, including the newly developed selective HDAC3 inhibitor LW3. We show HDAC1/2/3 are the co-essential isoforms that when co-inhibited halt CR transcription, making CR TF sites hyper-accessible and disrupting chromatin looping.


Assuntos
Elementos Facilitadores Genéticos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Rabdomiossarcoma/genética , Acetilação/efeitos dos fármacos , Linhagem Celular Tumoral , Cromatina/efeitos dos fármacos , Cromatina/metabolismo , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Ensaios de Triagem em Larga Escala , Inibidores de Histona Desacetilases/química , Histona Desacetilases/química , Humanos , Simulação de Dinâmica Molecular , Sondas Moleculares/química , Sondas Moleculares/farmacologia , Proteínas de Fusão Oncogênica/genética , Fatores de Transcrição Box Pareados/genética , Cultura Primária de Células , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Rabdomiossarcoma/patologia , Análise de Sequência de RNA , Transcrição Genética/efeitos dos fármacos
13.
Nat Commun ; 10(1): 2909, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266957

RESUMO

Cells form and use biomolecular condensates to execute biochemical reactions. The molecular properties of non-membrane-bound condensates are directly connected to the amino acid content of disordered protein regions. Lysine plays an important role in cellular function, but little is known about its role in biomolecular condensation. Here we show that protein disorder is abundant in protein/RNA granules and lysine is enriched in disordered regions of proteins in P-bodies compared to the entire human disordered proteome. Lysine-rich polypeptides phase separate into lysine/RNA-coacervates that are more dynamic and differ at the molecular level from arginine/RNA-coacervates. Consistent with the ability of lysine to drive phase separation, lysine-rich variants of the Alzheimer's disease-linked protein tau undergo coacervation with RNA in vitro and bind to stress granules in cells. Acetylation of lysine reverses liquid-liquid phase separation and reduces colocalization of tau with stress granules. Our study establishes lysine as an important regulator of cellular condensation.


Assuntos
Lisina/metabolismo , RNA/química , RNA/metabolismo , Proteínas tau/química , Proteínas tau/metabolismo , Acetilação , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Linhagem Celular , Grânulos Citoplasmáticos/genética , Grânulos Citoplasmáticos/metabolismo , Humanos , Lisina/química , Lisina/genética , RNA/genética , Proteínas tau/genética
14.
Eur J Med Chem ; 178: 116-130, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31177073

RESUMO

In this study, a series of novel HDAC inhibitors, using 1,2,4-oxadiazole-containing as the cap group, were synthesized and evaluated in vitro. Compound 14b, N-hydroxy-2-(methyl((3-(1-(4-methylbenzyl)piperidin-4-yl)-1,2,4-oxadiazol-5-yl)methyl)amino)pyrimidine-5-carboxamide, displayed the most potent histone deacetylase (HDAC) inhibition, especially against HDAC1, 2, and 3 with IC50 values of 1.8, 3.6 and 3.0 nM, respectively. In vitro antiproliferative studies confirmed that 14b was more potent than SAHA, with IC50 values against 12 types of cancer cell lines ranging from 9.8 to 44.9 nM. The results of Western blot assays showed that compound 14b can significantly up-regulate the acetylation of the biomarker his-H3 and molecular docking analyses revealed the mode of action of compound 14b against HDAC1. The results of flow-cytometry analysis suggested that compound 14b induces cell cycle arrest at the G1 phase and has apoptotic effects. Further investigation of the activity of 14b on the primary cells of three patients, showed IC50 values of 21.3, 61.1, and 77.4 nM. More importantly, an oral bioavailability of up to 53.52% was observed for 14b. An in vivo pharmacodynamic evaluation demonstrated that compound 14b can significantly inhibit tumor growth in a Daudi Burkitt's lymphoma xenograft model, with tumor inhibition rates of 53.8 and 46.1% observed at 20 and 10 mg/kg when administered p.o. and i.v., respectively. These results indicate that compound 14b may be a suitable lead for further evaluation and development as an HDAC inhibitor and a potent anticancer agent.


Assuntos
Antineoplásicos/uso terapêutico , Linfoma de Burkitt/tratamento farmacológico , Inibidores de Histona Desacetilases/uso terapêutico , Ácidos Hidroxâmicos/uso terapêutico , Oxidiazóis/uso terapêutico , Acetilação/efeitos dos fármacos , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Descoberta de Drogas , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Histona Desacetilase 1/química , Histona Desacetilase 1/metabolismo , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/farmacocinética , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/farmacocinética , Camundongos Endogâmicos NOD , Camundongos SCID , Simulação de Acoplamento Molecular , Estrutura Molecular , Oxidiazóis/síntese química , Oxidiazóis/farmacocinética , Ligação Proteica , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Eur J Med Chem ; 178: 259-286, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31195169

RESUMO

Acetylation, a key component in post-translational modification regulated by HATs and HDACs, is relevant to many crucial cellular contexts in organisms. Based on crucial pharmacophore patterns and the structure of targeted proteins, HAT inhibitors are designed and modified for higher affinity and better bioactivity. However, there are still some challenges, such as cell permeability, selectivity, toxicity and synthetic availability, which limit the improvement of HAT inhibitors. So far, only few HAT inhibitors have been approved for commercialization, indicating the urgent need for more successful and effective structure-based drug design and synthetic strategies. Here, we summarized three classes of HAT inhibitors based on their sources and structural scaffolds, emphasizing on their synthetic methods and structure-activity relationships and molecular mechanisms, hoping to facilitate the development and further application of HAT inhibitors.


Assuntos
Inibidores Enzimáticos/farmacologia , Histona Acetiltransferases/antagonistas & inibidores , Acetilação/efeitos dos fármacos , Animais , Domínio Catalítico , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Histona Acetiltransferases/química , Humanos , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade
16.
BMC Bioinformatics ; 20(1): 346, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208321

RESUMO

BACKGROUND: Acetylation on lysine is a widespread post-translational modification which is reversible and plays a crucial role in some biological activities. To better understand the mechanism, it is necessary to identify acetylation sites in proteins accurately. Computational methods are popular because they are more convenient and faster than experimental methods. In this study, we proposed a new computational method to predict acetylation sites in human by combining sequence features and structural features including physicochemical property (PCP), position specific score matrix (PSSM), auto covariation (AC), residue composition (RC), secondary structure (SS) and accessible surface area (ASA), which can well characterize the information of acetylated lysine sites. Besides, a two-step feature selection was applied, which combined mRMR and IFS. It finally trained a cascade classifier based on SVM, which successfully solved the imbalance between positive samples and negative samples and covered all negative sample information. RESULTS: The performance of this method is measured with a specificity of 72.19% and a sensibility of 76.71% on independent dataset which shows that a cascade SVM classifier outperforms single SVM classifier. CONCLUSIONS: In addition to the analysis of experimental results, we also made a systematic and comprehensive analysis of the acetylation data.


Assuntos
Biologia Computacional/métodos , Máquina de Vetores de Suporte , Acetilação , Sequência de Aminoácidos , Animais , Bases de Dados de Proteínas , Ontologia Genética , Humanos , Lisina/química , Camundongos , Anotação de Sequência Molecular , Matrizes de Pontuação de Posição Específica , Processamento de Proteína Pós-Traducional , Estrutura Secundária de Proteína , Proteínas/química , Proteínas/metabolismo , Ratos
17.
Food Chem ; 293: 396-407, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151627

RESUMO

To explore the involvement of protein lysine acetylation in the conversion of muscle to meat, a quantitative analysis of the acetylome in postmortem porcine muscle with or without antemortem stress was conducted. In total, 771 acetylpeptides containing 681 lysine acetylation sites mapping to 176 acetylproteins were identified. Acetylproteins were enriched in muscle contraction, carbohydrate metabolism, cell apoptosis and calcium signaling. Bioinformatic analysis suggests that preslaughter handling may be associated with glycolysis in postmortem muscle and the overall meat quality, via acetylation of multiple enzymes of glycogenolysis/glycolysis, regulate rigor mortis via acetylation of contractile, ATP production and calcium signaling-related proteins, and regulate stress response, cell apoptosis and meat tenderization via regulating the functions of heat shock proteins and permeability transition pore complex. This study provides the first overview of the acetylome in postmortem muscle as affected by preslaughter handling and broadens knowledge of the biochemistry regulating meat quality development.


Assuntos
Qualidade dos Alimentos , Lisina/metabolismo , Músculo Esquelético/metabolismo , Proteômica/métodos , Carne Vermelha/análise , Acetilação , Animais , Biologia Computacional/métodos , Glicólise , Proteínas de Choque Térmico/metabolismo , Proteínas de Carne/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Mudanças Depois da Morte , Estresse Psicológico , Suínos
18.
Life Sci ; 232: 116591, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31228513

RESUMO

AIMS: Calreticulin (CRT) is a multifunctional protein that protects endothelial cells by alleviating actin cytoskeleton injury, but the underlying mechanism remains unclear. CRT was recently identified as a novel acyltransferase; acetylation at the N-terminus of actin monomers strengthens actin polymerization. This study was undertaken to determine whether CRT protects human microvascular endothelial cells (HMECs) against microwave radiation through actin acetylation. MATERIALS AND METHODS: We prepared a eukaryotic-derived recombinant CRT and incubated the HMECs with it prior to microwave exposure. We then assessed cell injury and endothelial function, detected actin polymerization and acetylation after HMECs exposure to S-band high-power microwaves. Coimmunoprecipitation, pull-down, and ex vitro acetylation reaction were performed to determine whether actin is a novel substrate of CRT acyltransferase. Finally, we employed the mutant experiments to demonstrate the acetylation sites contributing to CRT acetyltransferase activity. KEY FINDINGS: Microwave radiation induced severe cell injury and endothelial contact dysfunction, reduced the polymerization of actin filaments, and destroyed the actin arrangement, ultimately reducing acetylated actin expression. CRT treatment upregulated actin acetylation levels, promoted polymerization, and facilitated thicker and longer F-actin stress fibre formation. Pre-incubation with CRT rescued microwave-induced cell injury, decreased actin acetylation, and rendered the actin cytoskeleton radiation-retardant. The level of acetyl-actin was positively correlated with actin polymerization. Actin was identified as a novel substrate of CRT, being acetylated mainly through the CRT P-domain at lys-206 and -207. SIGNIFICANCE: This work provides a better understanding of the underlying mechanism of CRT-induced cytoprotection, and suggests a novel therapeutic target for microwave radiation-related diseases with endothelial dysfunction.


Assuntos
Actinas/metabolismo , Calreticulina/farmacologia , Microvasos/efeitos dos fármacos , Acetilação/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Linhagem Celular , Citoproteção , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Microvasos/efeitos da radiação , Micro-Ondas , Substâncias Protetoras , Processamento de Proteína Pós-Traducional , Transdução de Sinais
19.
Carbohydr Polym ; 219: 431-440, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151544

RESUMO

Microwave-assisted extraction (MAE) of chitosan from dried fungal biomass of Rhizopus oryzae NRRL1526, obtained by culturing on potato dextrose broth (PDB), was performed and the optimal conditions required were identified using statistical analysis for the first time in this study. This microwave-assisted extraction (MAE) was compared against the conventional autoclave assisted method of chitosan extraction. The full factorial experimental design was used to investigate the impact of operating parameters of MAE, microwave power (100 W-500 W), and duration (10 min-30 min), on alkaline insoluble material (AIM) yield, chitosan yield, and degree of deacetylation (DDA). The effect of operating conditions was then evaluated using full factorial data analysis and optimum condition for MAE of chitosan was identified using response surface methodology to be 300 W and 22 min. This optimum condition identified was then further evaluated and the chitosan obtained characterized. Higher chitosan yield of 13.43 ± 0.3% (w/w) of fungal biomass was obtained when compared to that obtained, 6.67% ± 0.3% (w/w) of dry biomass, for the conventional extraction process. MAE yielded chitosan of higher degree of deacetylation, 94.6 ± 0.9% against 90.6 ± 0.5% (conventional heating), but the molecular weight was observed to be similar to that obtained by using conventional autoclave heating. MAE of chitosan was observed to yield a higher quantity of chitosan when compared to conventional extraction process and obtained chitosan exhibited a higher degree of deacetylation as well as molecular weight. The lower energy consumption of 0.11 kW h for MAE (5 kW h for conventional process) and the concomitant reduction in the energy bill to 1.1 cents from 50 cents, in addition to the above results, show that microwave irradiation is a more efficient and environment-friendly means to obtain chitosan from fungal biomass.


Assuntos
Quitosana , Micro-Ondas , Rhizopus/metabolismo , Acetilação , Biomassa , Quitosana/química , Quitosana/isolamento & purificação , Peso Molecular , Projetos de Pesquisa
20.
BMC Med Genet ; 20(1): 101, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31174490

RESUMO

BACKGROUND: N-terminal acetylation is a common protein modification in human cells and is catalysed by N-terminal acetyltransferases (NATs), mostly cotranslationally. The NAA10-NAA15 (NatA) protein complex is the major NAT, responsible for acetylating ~ 40% of human proteins. Recently, NAA10 germline variants were found in patients with the X-linked lethal Ogden syndrome, and in other familial or de novo cases with variable degrees of developmental delay, intellectual disability (ID) and cardiac anomalies. METHODS: Here we report a novel NAA10 (NM_003491.3) c.248G > A, p.(R83H) missense variant in NAA10 which was detected by whole exome sequencing in two unrelated boys with intellectual disability, developmental delay, ADHD like behaviour, very limited speech and cardiac abnormalities. We employ in vitro acetylation assays to functionally test the impact of this variant on NAA10 enzyme activity. RESULTS: Functional characterization of NAA10-R83H by in vitro acetylation assays revealed a reduced enzymatic activity of monomeric NAA10-R83H. This variant is modelled to have an altered charge density in the acetyl-coenzyme A (Ac-CoA) binding region of NAA10. CONCLUSIONS: We show that NAA10-R83H has a reduced monomeric catalytic activity, likely due to impaired enzyme-Ac-CoA binding. Our data support a model where reduced NAA10 and/or NatA activity cause the phenotypes observed in the two patients.


Assuntos
Acetiltransferases/genética , Deficiência Intelectual/genética , Microcefalia/genética , Mutação de Sentido Incorreto , Acetiltransferase N-Terminal A/genética , Acetiltransferase N-Terminal E/genética , Acetilação , Acetiltransferases/metabolismo , Sequência de Aminoácidos , Pré-Escolar , Humanos , Lactente , Masculino , Modelos Moleculares , Acetiltransferase N-Terminal A/química , Acetiltransferase N-Terminal A/metabolismo , Acetiltransferase N-Terminal E/química , Acetiltransferase N-Terminal E/metabolismo , Fenótipo , Domínios Proteicos , Homologia de Sequência de Aminoácidos , Sequenciamento Completo do Exoma
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