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1.
J Med Food ; 24(9): 978-986, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34524028

RESUMO

Epigenetic regulation by histone acetyltransferase (HAT) is associated with various biological processes and the progression of diseases, including nonalcoholic fatty liver disease (NAFLD). The objective of this study was to investigate whether the hypolipidemic properties of black mulberry (Morus atropurpurea Roxb.) fruit extract (BME) contribute toward protection against NAFLD by HAT inhibition. HepG2 cells were treated with oleic and palmitic acids to induce lipid accumulation, which was significantly attenuated by the treatment with BME at 50 and 100 µg/mL. BME also markedly reduced the expression of proteins associated with lipogenesis, which was attributed to the BME-mediated downregulation of lipogenic genes in HepG2 cells. BME significantly inhibited in vitro total HAT and p300 activities. In addition, BME suppressed total acetylated lysine as well as specific histone acetylation of proteins H3K14 and H3K27 in HepG2 cells. Mice were then fed with either a chow diet or western diet (WD), with or without BME (1%, w/w) supplementation, for 12 weeks to confirm hypolipidemic activity of BME. BME attenuated serum nonesterified fatty acids and low-density lipoprotein (LDL) cholesterol levels, which was likely associated with the downregulation of hepatic lipogenic gene expression in WD-fed obese mice. Taken together, the hypolipidemic activity of BME was observed in HepG2 cells treated with fatty acids as well as in livers of obese mice, and the hepatoprotection of BME is likely associated with the inhibition of acetylation. Further investigation is warranted to determine whether BME can be developed into an efficacious dietary intervention to attenuate the progression of NAFLD by epigenetic regulation in clinical settings.


Assuntos
Morus , Hepatopatia Gordurosa não Alcoólica , Acetilação , Animais , Dieta Hiperlipídica/efeitos adversos , Epigênese Genética , Frutas/metabolismo , Células Hep G2 , Histonas/metabolismo , Humanos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia
2.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443600

RESUMO

Organotin(IV) compounds are a class of non-platinum metallo-conjugates exhibiting antitumor activity. The effects of different organotin types has been related to several mechanisms, including their ability to modify acetylation protein status and to promote apoptosis. Here, we focus on triorganotin(IV) complexes of butyric acid, a well-known HDAC inhibitor with antitumor properties. The conjugated compounds were synthesized and characterised by FTIR spectroscopy, multi-nuclear (1H, 13C and 119Sn) NMR, and mass spectrometry (ESI-MS). In the triorganotin(IV) complexes, an anionic monodentate butyrate ligand was observed, which coordinated the tin atom on a tetra-coordinated, monomeric environment similar to ester. FTIR and NMR findings confirm this structure both in solid state and solution. The antitumor efficacy of the triorganotin(IV) butyrates was tested in colon cancer cells and, among them, tributyltin(IV) butyrate (BT2) was selected as the most efficacious. BT2 induced G2/M cell cycle arrest, ER stress, and apoptotic cell death. These effects were obtained using low concentrations of BT2 up to 1 µM, whereas butyric acid alone was completely inefficacious, and the parent compound TBT was poorly effective at the same treatment conditions. To assess whether butyrate in the coordinated form maintains its epigenetic effects, histone acetylation was evaluated and a dramatic decrease in acetyl-H3 and -H4 histones was found. In contrast, butyrate alone stimulated histone acetylation at a higher concentration (5 mM). BT2 was also capable of preventing histone acetylation induced by SAHA, another potent HDAC inhibitor, thus suggesting that it may activate HDACs. These results support a potential use of BT2, a novel epigenetic modulator, in colon cancer treatment.


Assuntos
Apoptose/genética , Ácido Butírico/química , Neoplasias do Colo/patologia , Estresse do Retículo Endoplasmático/genética , Epigênese Genética/efeitos dos fármacos , Compostos de Trialquitina/química , Compostos de Trialquitina/farmacologia , Acetilação/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Histona Desacetilases/metabolismo , Humanos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos
3.
Nat Commun ; 12(1): 5056, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34417458

RESUMO

Melanoma cells rely on developmental programs during tumor initiation and progression. Here we show that the embryonic stem cell (ESC) factor Sall4 is re-expressed in the Tyr::NrasQ61K; Cdkn2a-/- melanoma model and that its expression is necessary for primary melanoma formation. Surprisingly, while Sall4 loss prevents tumor formation, it promotes micrometastases to distant organs in this melanoma-prone mouse model. Transcriptional profiling and in vitro assays using human melanoma cells demonstrate that SALL4 loss induces a phenotype switch and the acquisition of an invasive phenotype. We show that SALL4 negatively regulates invasiveness through interaction with the histone deacetylase (HDAC) 2 and direct co-binding to a set of invasiveness genes. Consequently, SALL4 knock down, as well as HDAC inhibition, promote the expression of an invasive signature, while inhibition of histone acetylation partially reverts the invasiveness program induced by SALL4 loss. Thus, SALL4 appears to regulate phenotype switching in melanoma through an HDAC2-mediated mechanism.


Assuntos
Epigênese Genética , Melanoma/genética , Melanoma/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Fator de Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Animais , Sequência de Bases , Carcinogênese/genética , Carcinogênese/patologia , Adesão Celular/genética , Linhagem Celular Tumoral , Linhagem da Célula , Proliferação de Células , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Histona Desacetilase 2/metabolismo , Histonas/metabolismo , Humanos , Melanócitos/metabolismo , Melanócitos/patologia , Camundongos Nus , Camundongos Transgênicos , Invasividade Neoplásica , Micrometástase de Neoplasia , Ligação Proteica , Carga Tumoral
4.
Pestic Biochem Physiol ; 178: 104908, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34446212

RESUMO

Histone acetylation plays important roles in eukaryotic chromatin modification and gene expression regulation. Acetylation levels are modulated by histone deacetylases (HDACs), which function as key epigenetic factors that regulate gene expression in response to various stresses. HDT701, a member of the HD2 subfamily of HDACs, plays crucial roles in plant responses to abiotic stress and pathogen infection. Here, we analysed the expression pattern of SbHDT701 in sorghum. Real-time fluorescence quantitative PCR (RT-qPCR) results showed that expression of SbHDT701 was tissue-specific, and up-regulated under drought (d-mannitol) and salt (NaCl) stresses. We also determined the optimal expression conditions for SbHDT701 protein accumulation, and successfully expressed and purified SbHDT701 protein. Besides, overexpression of SbHDT701 in could promote the growth of recombinant cells under abiotic stress. SbHDT701 expression in Escherichia coli also increased acetylation modification levels following treatment with 750 mM NaCl, and 100 mM or 300 mM d-mannitol. In summary, the sorghum HDAC SbHDT701 mediates stress responses by enhancing acetylation modification levels.


Assuntos
Histona Desacetilases , Sorghum , Acetilação , Secas , Regulação da Expressão Gênica de Plantas , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Sorghum/genética
5.
FASEB J ; 35(9): e21811, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34369620

RESUMO

Actin cytoskeletal reorganization plays an important role in regulating smooth muscle contraction, which is essential for the modulation of various physiological functions including airway tone. The adapter protein Abi1 (Abelson interactor 1) participates in the control of smooth muscle contraction. The mechanisms by which Abi1 coordinates smooth muscle function are not fully understood. Here, we found that contractile stimulation elicited Abi1 acetylation in human airway smooth muscle (HASM) cells. Mutagenesis analysis identified lysine-416 (K416) as a major acetylation site. Replacement of K416 with Q (glutamine) enhanced the interaction of Abi1 with neuronal Wiskott-Aldrich syndrome protein (N-WASP), an important actin-regulatory protein. Moreover, the expression of K416Q Abi1 promoted actin polymerization and smooth muscle contraction without affecting myosin light chain phosphorylation at Ser-19 and vimentin phosphorylation at Ser-56. Furthermore, p300 is a lysine acetyltransferase that catalyzes acetylation of histone and non-histone proteins in various cell types. Here, we discovered that a portion of p300 was localized in the cytoplasm of HASM cells. Knockdown of p300 reduced the agonist-induced Abi1 acetylation in HASM cells and in mouse airway smooth muscle tissues. Smooth muscle conditional knockout of p300 inhibited actin polymerization and the contraction of airway smooth muscle tissues without affecting myosin light chain phosphorylation and vimentin phosphorylation. Together, our results suggest that contractile stimulation induces Abi1 acetylation via p300 in smooth muscle. Acetylation at K416 promotes the coupling of Abi1 with N-WASP, which facilitates actin polymerization and smooth muscle contraction. This is a novel acetylation-dependent regulation of the actin cytoskeleton in smooth muscle.


Assuntos
Citoesqueleto de Actina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas do Citoesqueleto/metabolismo , Contração Muscular/fisiologia , Músculo Liso/metabolismo , Acetilação , Animais , Células Cultivadas , Proteína p300 Associada a E1A/metabolismo , Humanos , Lisina Acetiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos de Músculo Liso/metabolismo , Cadeias Leves de Miosina/metabolismo , Fosforilação/fisiologia , Transdução de Sinais/fisiologia , Proteína Neuronal da Síndrome de Wiskott-Aldrich/metabolismo
6.
J Cell Sci ; 134(2)2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34432034

RESUMO

Silicosis is characterized by silica exposure-induced lung interstitial fibrosis and formation of silicotic nodules, resulting in lung stiffening. The acetylation of microtubules mediated by α-tubulin N-acetyltransferase 1 (α-TAT1) is a posttranslational modification that promotes microtubule stability in response to mechanical stimulation. α-TAT1 and downstream acetylated α-tubulin (Ac-α-Tub) are decreased in silicosis, promoting the epithelial-mesenchymal transition (EMT); however, the underlying mechanisms are unknown. We found that silica, matrix stiffening or their combination triggered Ac-α-Tub downregulation in alveolar epithelial cells, followed by DNA damage and replication stress. α-TAT1 elevated Ac-α-Tub to limit replication stress and the EMT via trafficking of p53-binding protein 1 (53BP1, also known as TP53BP1). The results provide evidence that α-TAT1 and Ac-α-Tub inhibit the EMT and silicosis fibrosis by preventing 53BP1 mislocalization and relieving DNA damage. This study provides insight into how the cell cycle is regulated during the EMT and why the decrease in α-TAT1 and Ac-α-Tub promotes silicosis fibrosis. This article has an associated First Person interview with the first authors of the paper.


Assuntos
Transição Epitelial-Mesenquimal , Tubulina (Proteína) , Acetilação , Dano ao DNA , Transição Epitelial-Mesenquimal/genética , Humanos , Processamento de Proteína Pós-Traducional , Dióxido de Silício/toxicidade , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo
7.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360712

RESUMO

Histone deacetylase (HDAC) and histone acetyltransferase (HAT) regulate transcription and the most important functions of cells by acetylating/deacetylating histones and non-histone proteins. These proteins are involved in cell survival and death, replication, DNA repair, the cell cycle, and cell responses to stress and aging. HDAC/HAT balance in cells affects gene expression and cell signaling. There are very few studies on the effects of stroke on non-histone protein acetylation/deacetylation in brain cells. HDAC inhibitors have been shown to be effective in protecting the brain from ischemic damage. However, the role of different HDAC isoforms in the survival and death of brain cells after stroke is still controversial. HAT/HDAC activity depends on the acetylation site and the acetylation/deacetylation of the main proteins (c-Myc, E2F1, p53, ERK1/2, Akt) considered in this review, that are involved in the regulation of cell fate decisions. Our review aims to analyze the possible role of the acetylation/deacetylation of transcription factors and signaling proteins involved in the regulation of survival and death in cerebral ischemia.


Assuntos
Isquemia Encefálica/metabolismo , Histona Acetiltransferases/metabolismo , Histona Desacetilases/metabolismo , Modelos Neurológicos , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Fatores de Transcrição/metabolismo , Acetilação , Animais , Humanos
8.
Int J Mol Sci ; 22(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34360775

RESUMO

Coupling glycolysis and mitochondrial tricarboxylic acid cycle, pyruvate dehydrogenase (PDH) complex (PDHC) is highly responsive to cellular demands through multiple mechanisms, including PDH phosphorylation. PDHC also produces acetyl-CoA for protein acetylation involved in circadian regulation of metabolism. Thiamine (vitamin B1) diphosphate (ThDP) is known to activate PDH as both coenzyme and inhibitor of the PDH inactivating kinases. Molecular mechanisms integrating the function of thiamine-dependent PDHC into general redox metabolism, underlie physiological fitness of a cell or an organism. Here, we characterize the daytime- and thiamine-dependent changes in the rat brain PDHC function, expression and phosphorylation, assessing their impact on protein acetylation and metabolic regulation. Morning administration of thiamine significantly downregulates both the PDH phosphorylation at Ser293 and SIRT3 protein level, the effects not observed upon the evening administration. This action of thiamine nullifies the daytime-dependent changes in the brain PDHC activity and mitochondrial acetylation, inducing diurnal difference in the cytosolic acetylation and acetylation of total brain proteins. Screening the daytime dependence of central metabolic enzymes and proteins of thiol/disulfide metabolism reveals that thiamine also cancels daily changes in the malate dehydrogenase activity, opposite to those of the PDHC activity. Correlation analysis indicates that thiamine abrogates the strong positive correlation between the total acetylation of the brain proteins and PDHC function. Simultaneously, thiamine heightens interplay between the expression of PDHC components and total acetylation or SIRT2 protein level. These thiamine effects on the brain acetylation system change metabolic impact of acetylation. The changes are exemplified by the thiamine enhancement of the SIRT2 correlations with metabolic enzymes and proteins of thiol-disulfide metabolism. Thus, we show the daytime- and thiamine-dependent changes in the function and phosphorylation of brain PDHC, contributing to regulation of the brain acetylation system and redox metabolism. The daytime-dependent action of thiamine on PDHC and SIRT3 may be of therapeutic significance in correcting perturbed diurnal regulation.


Assuntos
Encéfalo/metabolismo , Cetona Oxirredutases/metabolismo , Mitocôndrias/enzimologia , Proteínas Mitocondriais/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Sirtuínas/metabolismo , Tiamina/farmacologia , Acetilação/efeitos dos fármacos , Animais , Ciclo do Ácido Cítrico/efeitos dos fármacos , Masculino , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Fatores de Tempo
9.
Org Biomol Chem ; 19(33): 7186-7189, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34378606

RESUMO

Tetracyclic triterpenes and steroids are pharmacologically important molecules, and acetylation could improve their bioactivities. In this study, a highly regio- and stereo-specific acetyltransferase, AmAT19, was discovered from Astragalus membranaceus. AmAT19 could selectively catalyze the 6α-OH acetylation of four tetracyclic triterpenes and steroids. The strict selectivity is associated with different orientations of the 6α/ß-OH as indicated by molecular docking. Acetylated products 1a, 3a and 4a remarkably increased the inhibitory activity against the 3-chymotrypsin-like protease (3CLpro) of SARS-CoV-2, compared to 1, 3, and 4. AmAT19 could be a promising catalyst for specific 6α-OH acetylation to expand the molecular diversity of triterpenes and steroids.


Assuntos
Acetiltransferases/metabolismo , Astrágalo (Planta)/enzimologia , Esteroides/metabolismo , Triterpenos/metabolismo , Acetilação , Catálise
10.
Int J Mol Sci ; 22(16)2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34445236

RESUMO

Sepsis-induced liver dysfunction (SILD) is a common event and is strongly associated with mortality. Establishing a causative link between protein post-translational modification and diseases is challenging. We studied the relationship among lysine acetylation (Kac), sirtuin (SIRTs), and the factors involved in SILD, which was induced in LPS-stimulated HepG2 cells. Protein hyperacetylation was observed according to SIRTs reduction after LPS treatment for 24 h. We identified 1449 Kac sites based on comparative acetylome analysis and quantified 1086 Kac sites on 410 proteins for acetylation. Interestingly, the upregulated Kac proteins are enriched in glycolysis/gluconeogenesis pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) category. Among the proteins in the glycolysis pathway, hyperacetylation, a key regulator of lactate level in sepsis, was observed at three pyruvate kinase M2 (PKM2) sites. Hyperacetylation of PKM2 induced an increase in its activity, consequently increasing the lactate concentration. In conclusion, this study is the first to conduct global profiling of Kac, suggesting that the Kac mechanism of PKM2 in glycolysis is associated with sepsis. Moreover, it helps to further understand the systematic information regarding hyperacetylation during the sepsis process.


Assuntos
Proteínas de Transporte/metabolismo , Lipopolissacarídeos/toxicidade , Fígado/enzimologia , Proteínas de Membrana/metabolismo , Sepse/enzimologia , Hormônios Tireóideos/metabolismo , Acetilação/efeitos dos fármacos , Células Hep G2 , Humanos , Lisina/metabolismo , Sepse/induzido quimicamente
11.
Int J Mol Sci ; 22(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34445348

RESUMO

The periodontal ligament is a soft connective tissue embedded between the alveolar bone and cementum, the surface hard tissue of teeth. Periodontal ligament fibroblasts (PDLF) actively express osteo/cementogenic genes, which contribute to periodontal tissue homeostasis. However, the key factors maintaining the osteo/cementogenic abilities of PDLF remain unclear. We herein demonstrated that PPARγ was expressed by in vivo periodontal ligament tissue and its distribution pattern correlated with alkaline phosphate enzyme activity. The knockdown of PPARγ markedly reduced the osteo/cementogenic abilities of PDLF in vitro, whereas PPARγ agonists exerted the opposite effects. PPARγ was required to maintain the acetylation status of H3K9 and H3K27, active chromatin markers, and the supplementation of acetyl-CoA, a donor of histone acetylation, restored PPARγ knockdown-induced decreases in the osteo/cementogenic abilities of PDLF. An RNA-seq/ChIP-seq combined analysis identified four osteogenic transcripts, RUNX2, SULF2, RCAN2, and RGMA, in the PPARγ-dependent active chromatin region marked by H3K27ac. Furthermore, RUNX2-binding sites were selectively enriched in the PPARγ-dependent active chromatin region. Collectively, these results identified PPARγ as the key transcriptional factor maintaining the osteo/cementogenic abilities of PDLF and revealed that global H3K27ac modifications play a role in the comprehensive osteo/cementogenic transcriptional alterations mediated by PPARγ.


Assuntos
Fibroblastos/fisiologia , Histonas/metabolismo , PPAR gama/fisiologia , Ligamento Periodontal/fisiologia , Acetilação , Diferenciação Celular/genética , Células Cultivadas , Cementogênese/genética , Cementogênese/fisiologia , Regulação da Expressão Gênica , Histona Acetiltransferases/metabolismo , Histonas/química , Humanos , Osteogênese/genética , Osteogênese/fisiologia , Ligamento Periodontal/citologia , Processamento de Proteína Pós-Traducional/genética
12.
Environ Pollut ; 284: 117518, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34261222

RESUMO

Perfluorooctane sulfonate (PFOS), an artificial perfluorinated compound, has been associated with male reproductive disorders. Histone modifications are important epigenetic mediators; however, the impact of PFOS exposure on testicular steroidogenesis through histone modification regulations remains to be elucidated. In this study, we examined the roles of histone modifications in regulating steroid hormone production in male rats chronically exposed to low-level PFOS. The results indicate that PFOS exposure significantly up-regulated the expressions of StAR, CYP11A1 and 3ß-HSD, while CYP17A1 and 17ß-HSD were down-regulated, thus contributing to the elevated progesterone and testosterone levels. Furthermore, PFOS significantly increased the histones H3K9me2, H3K9ac and H3K18ac while reduced H3K9me3 in rat testis. It is known that histone modifications are closely involved in gene transcription. Therefore, to investigate the association between histone modifications and steroidogenic gene regulation, the levels of these histone marks were further measured in steroidogenic gene promoter regions by ChIP. It was found that H3K18ac was augmented in Cyp11a1 promoter, and H3K9ac was increased in Hsd3b after PFOS exposure, which is proposed to result in the activation of CYP11A1 and 3ß-HSD, respectively. To sum up, chronic low-level PFOS exposure activated key steroidogenic gene expression through enhancing histone acetylation (H3K9ac and H3K18ac), ultimately stimulating steroid hormone biosynthesis in rat testis.


Assuntos
Histonas , Testículo , Acetilação , Ácidos Alcanossulfônicos , Animais , Fluorcarbonetos , Histonas/metabolismo , Masculino , Ratos , Testículo/metabolismo , Testosterona/metabolismo
13.
J Immunol ; 207(3): 913-922, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34290107

RESUMO

Metabolic programming is integrally linked to immune cell function. Nowhere is this clearer than in the differentiation of macrophages. Proinflammatory M1 macrophages primarily use glycolysis as a rapid energy source but also to generate antimicrobial compounds, whereas alternatively activated M2 macrophages primarily rely on oxidative phosphorylation for the longevity required for proper wound healing. mTOR signaling has been demonstrated to be a key regulator of immune cell metabolism and function. mTORC2 signaling is required for the generation of M2 macrophages, whereas the role of mTORC1 signaling, a key regulator of glycolysis, has been controversial. By using genetic deletion of mTORC1 signaling in C57BL/6 mouse macrophages, we observed enhanced M1 macrophage function in vitro and in vivo. Surprisingly, this enhancement occurred despite a significant defect in M1 macrophage glycolytic metabolism. Mechanistically, enhanced M1 function occurred because of inhibition of the class III histone deacetylases the sirtuins, resulting in enhanced histone acetylation. Our findings provide a counterpoint to the paradigm that enhanced immune cell function must occur in the presence of increased cellular metabolism and identifies a potential, pharmacologic target for the regulation of inflammatory responses.


Assuntos
Inflamação/imunologia , Macrófagos/imunologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Acetilação , Animais , Células Cultivadas , Reprogramação Celular , Citocinas/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Sirtuínas/metabolismo , Células Th1/imunologia
14.
Nat Commun ; 12(1): 4618, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326347

RESUMO

The transcriptional co-activator and acetyltransferase p300 is required for fundamental cellular processes, including differentiation and growth. Here, we report that p300 forms phase separated condensates in the cell nucleus. The phase separation ability of p300 is regulated by autoacetylation and relies on its catalytic core components, including the histone acetyltransferase (HAT) domain, the autoinhibition loop, and bromodomain. p300 condensates sequester chromatin components, such as histone H3 tail and DNA, and are amplified through binding of p300 to the nucleosome. The catalytic HAT activity of p300 is decreased due to occlusion of the active site in the phase separated droplets, a large portion of which co-localizes with chromatin regions enriched in H3K27me3. Our findings suggest a model in which p300 condensates can act as a storage pool of the protein with reduced HAT activity, allowing p300 to be compartmentalized and concentrated at poised or repressed chromatin regions.


Assuntos
Núcleo Celular/metabolismo , Cromatina/metabolismo , Proteína p300 Associada a E1A/metabolismo , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Células Cultivadas , Proteína p300 Associada a E1A/química , Humanos , Domínios Proteicos
15.
Am J Physiol Cell Physiol ; 321(3): C519-C534, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34319827

RESUMO

Mitochondria are recognized as signaling organelles, because under stress, mitochondria can trigger various signaling pathways to coordinate the cell's response. The specific pathway(s) engaged by mitochondria in response to mitochondrial energy defects in vivo and in high-energy tissues like the heart are not fully understood. Here, we investigated cardiac pathways activated in response to mitochondrial energy dysfunction by studying mice with cardiomyocyte-specific loss of the mitochondrial phosphate carrier (SLC25A3), an established model that develops cardiomyopathy as a result of defective mitochondrial ATP synthesis. Mitochondrial energy dysfunction induced a striking pattern of acylome remodeling, with significantly increased posttranslational acetylation and malonylation. Mass spectrometry-based proteomics further revealed that energy dysfunction-induced remodeling of the acetylome and malonylome preferentially impacts mitochondrial proteins. Acetylation and malonylation modified a highly interconnected interactome of mitochondrial proteins, and both modifications were present on the enzyme isocitrate dehydrogenase 2 (IDH2). Intriguingly, IDH2 activity was enhanced in SLC25A3-deleted mitochondria, and further study of IDH2 sites targeted by both acetylation and malonylation revealed that these modifications can have site-specific and distinct functional effects. Finally, we uncovered a novel cross talk between the two modifications, whereby mitochondrial energy dysfunction-induced acetylation of sirtuin 5 (SIRT5), inhibited its function. Because SIRT5 is a mitochondrial deacylase with demalonylase activity, this finding suggests that acetylation can modulate the malonylome. Together, our results position acylations as an arm of the mitochondrial response to energy dysfunction and suggest a mechanism by which focal disruption to the energy production machinery can have an expanded impact on global mitochondrial function.


Assuntos
Cardiomiopatias/genética , Proteínas de Transporte de Cátions/genética , Isocitrato Desidrogenase/genética , Mitocôndrias Cardíacas/metabolismo , Proteínas Mitocondriais/genética , Miócitos Cardíacos/metabolismo , Proteínas de Transporte de Fosfato/genética , Processamento de Proteína Pós-Traducional , Proteínas Carreadoras de Solutos/genética , Acetilação , Animais , Transporte Biológico , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Proteínas de Transporte de Cátions/deficiência , Metabolismo Energético , Feminino , Redes Reguladoras de Genes , Isocitrato Desidrogenase/metabolismo , Masculino , Malonatos/metabolismo , Camundongos , Camundongos Knockout , Mitocôndrias Cardíacas/genética , Mitocôndrias Cardíacas/patologia , Proteínas Mitocondriais/deficiência , Modelos Moleculares , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/patologia , Proteínas de Transporte de Fosfato/deficiência , Fosfatos , Conformação Proteica , Mapeamento de Interação de Proteínas , Transdução de Sinais , Sirtuínas/genética , Sirtuínas/metabolismo , Proteínas Carreadoras de Solutos/deficiência
16.
Methods Mol Biol ; 2342: 781-808, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34272717

RESUMO

Major routes of metabolism for marketed drugs are predominately driven by enzyme families such as cytochromes P450 and UDP-glucuronosyltransferases. Less studied conjugative enzymes, like N-acetyltransferases (NATs), are commonly associated with detoxification pathways. However, in the clinic, the high occurrence of NAT polymorphism that leads to slow and fast acetylator phenotypes in patient populations has been linked to toxicity for a multitude of drugs. A key example of this is the observed clinical toxicity in patients who exhibit the slow acetylator phenotype and were treated with isoniazid. Toxicity in patients has led to detailed characterization of the two NAT isoforms and their polymorphic genotypes. Investigation in recombinant enzymes, genotyped hepatocytes, and in vivo transgenic models coupled with acetylator status-driven clinical studies have helped understand the role of NATs in drug development, clinical study design and outcomes, and potential roles in human disease models. The selected case studies herein document NAT enzyme kinetics to explore substrate overlap from two human isoforms, preclinical species considerations, and clinical genotype population concerns.


Assuntos
Acetiltransferases/genética , Acetiltransferases/metabolismo , Isoniazida/efeitos adversos , Acetilação , Animais , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Genótipo , Hepatócitos/metabolismo , Humanos , Isoniazida/farmacocinética , Cinética , Polimorfismo Genético
17.
J Photochem Photobiol B ; 221: 112250, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34243022

RESUMO

There is a current concern, among the scientific community, on the pollutants classified as "persistent organic pollutants (POPs)". Pharmaceuticals and personal care products (PPCPs) belong to this family of contaminants; therefore, it is necessary to find more efficient techniques able to achieve their removal from the environment. This study focuses on two different pharmaceuticals: carbamazepine and atenolol, chosen for their widespread use and their different chemical and medical properties. In this work, an organic dye, acetylated riboflavin, has been used in combination with visible light to achieve the photodegradation of these two POPs in <2 h. Moreover, photophysical experiments demonstrated the involvement of the singlet and triplet excited states of acetylated riboflavin and the generated singlet oxygen in the removal of these drugs. Besides, a detailed UFLC-MS-MS analysis of the photoproducts confirmed the oxidation of the drugs. Finally, a plausible mechanism has been postulated.


Assuntos
Carbamazepina/química , Luz , Fotólise/efeitos da radiação , Riboflavina/química , Poluentes Químicos da Água/química , Acetilação , Atenolol/química , Catálise , Cinética , Fotólise/efeitos dos fármacos , Oxigênio Singlete/química , Poluentes Químicos da Água/metabolismo
18.
Sheng Li Xue Bao ; 73(3): 527-534, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34230954

RESUMO

Oogenesis is the basic reproductive process of female mammals and is essential for fertilization and embryo development. Recent studies have shown that epigenetic modifications play an important role in the regulation of mammalian reproductive processes (such as oogenesis, spermatogenesis, preimplantation embryo development and sex differentiation). Taking histone acetylation as an instance, the dynamic changes of histone acetyltransferases (HATs) and deacetylases (HDACs) are involved in the regulation of gene activation and inactivation when numerous key physiological events occur during reproduction. Thereinto, HDAC1 and HDAC2, which are highly homologous in terms of both structure and function, play a pivotal role in murine oogenesis. HDAC1 and 2 jointly regulate the global transcription and the incidence of apoptosis of growing oocytes and affect its subsequent growth and development, which reflects their compensatory function. In addition, HDAC1 and 2 also play a specific part in oogenesis respectively. It has shown that HDAC2 is more critical than HDAC1 for oocyte development, which regulates de novo DNA methylation and chromosome segregation. Reciprocally, HDAC1 is more critical than HDAC2 for preimplantation development. Deficiency of HDAC1 causes the decreased proliferation of embryonic stem cells and the smaller embryoid bodies with irregular shape. In this review, we summarized the role and the current research progress of HDAC1/2 in murine oogenesis, to provide a reference for further understanding the relationship between epigenetic modifications and reproductive regulation.


Assuntos
Histona Desacetilase 1 , Histona Desacetilase 2 , Acetilação , Animais , Desenvolvimento Embrionário , Feminino , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Histona Desacetilases/metabolismo , Masculino , Camundongos , Oócitos , Oogênese
19.
Microb Pathog ; 158: 105109, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34314811

RESUMO

Late expression factor 3 (LEF3) is a single-stranded DNA binding protein of Bombyx mori nucleopolyhedrovirus (BmNPV) with multiple functions. It is an essential factor for viral DNA replication and plays an important regulatory role during BmNPV infection. Our recent quantitative analysis of protein acetylome revealed for the first time that LEF3 can be acetylated at four lysine residues during the viral infection, but the underlying mechanism is unknown. Among the modification sites, two of them (K18 and K27) are located in the conserved nuclear localization sequence region. The acetylation level for K18 especially was up-regulated approximately 7.4 times after 36 h of post-infection. To understand the regulatory function of this modification, site-direct mutagenesis for acetylated mimic (K18Q) or deacetylated mimic (K18R) mutants was performed on LEF3. The fluorescence analysis results showed that the replication capacity of the virus was significantly reduced after K18 acetylation. Meanwhile, co-localization analysis revealed that acetylation at K18 caused LEF3 to lose its nuclear targeting ability and affected the interaction between LEF3 and P143, retaining P143 in the cytoplasm. And further Yeast two-hybrid analysis results also confirmed that the acetylation at K18 did affect the interaction between LEF3 and P143. In conclusion, the acetylation of LEF3 at K18 might act as one of the antiviral strategies for silkworm host by affecting nuclear localization of LEF3, interaction with P143, and then blocking viral replication.


Assuntos
Bombyx , Replicação Viral , Acetilação , Animais , Replicação do DNA , DNA Viral , Nucleopoliedrovírus , Proteínas Virais/genética , Proteínas Virais/metabolismo
20.
Chem Pharm Bull (Tokyo) ; 69(7): 652-660, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34193714

RESUMO

The hydrocarbon-chain packing structure of intercellular lipids in the stratum corneum (SC) is critical to the skin's barrier function. We previously found that formation of V-shaped ceramide reduces the barrier function of skin. There are few agents, apart from ceramides and fatty acids that can improve the orthorhombic packing (Orth) ratio of the intercellular lipid packing structure. In this study, we investigated agents that directly increase the Orth ratio. We selected an intercellular lipid model consisting of ceramide, cholesterol, and palmitic acid and performed differential scanning calorimetry. We focused on natural moisturizing factor components in the SC, and therefore investigated amino acids and their derivatives. The results of our intercellular lipid model-based study indicate that N-acetyl-L-hydroxyproline (AHYP), remarkably, maintains the lamellar structure. We verified the effect of AHYP on the lamellar structure and hydrocarbon chain packing structure of intercellular lipids using time-resolved X-ray diffraction measurements of human SC. We also determined the direct physicochemical effects of AHYP on the Orth ratio of the hydrocarbon-chain packing structure. Hence, the results of our human SC study suggest that AHYP preserves skin barrier function by maintaining the hydrocarbon-chain packing structure of intercellular lipids via electrostatic repulsion. These findings will facilitate the development of skincare formulation that can maintain the skin's barrier function.


Assuntos
Aminoácidos/metabolismo , Absorção Cutânea , Acetilação , Aminoácidos/química , Varredura Diferencial de Calorimetria , Colesterol/química , Epiderme/química , Humanos , Hidroxiprolina/química , Hidroxiprolina/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Nanoestruturas/química , Ácido Palmítico/química , Espalhamento a Baixo Ângulo , Difração de Raios X
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