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1.
Methods Mol Biol ; 2589: 317-335, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36255634

RESUMO

Helicobacter pylori infection is one of the leading factors that promotes, among other diseases, gastric cancer (GC). Infection of gastric epithelial cells (GECs) by H. pylori enhances the expression as well as acetylation of the E3 ubiquitin ligase SIAH2 which promotes GC progression. The histone acetyltransferase (HAT) activity of p300 catalyzes SIAH2 acetylation following H. pylori infection. Since reactive oxygen species (ROS) generation in H. pylori-infected GECs accelerates GC progression, acetylation-mediated SIAH2 regulation might be a crucial modifier of ROS generation in the infected GECs. Here, we describe a compendium of methods to evaluate the effects of HAT/lysine acetyl transferase (KAT) inhibitors (HAT/KATi) on SIAH2-mediated ROS regulation in H. pylori-infected GECs.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Helicobacter pylori/metabolismo , Infecções por Helicobacter/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Mucosa Gástrica/metabolismo , Lisina/metabolismo , Células Epiteliais/metabolismo , Neoplasias Gástricas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Histona Acetiltransferases/metabolismo , Transferases/metabolismo
2.
Methods Mol Biol ; 2589: 269-291, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36255631

RESUMO

Posttranslational modifications are important for protein functions and cellular signaling pathways. The acetylation of lysine residues is catalyzed by histone acetyltransferases (HATs) and removed by histone deacetylases (HDACs), with the latter being grouped into four phylogenetic classes. The class III of the HDAC family, the sirtuins (SIRTs), contributes to gene expression, genomic stability, cell metabolism, and tumorigenesis. Thus, several specific SIRT inhibitors (SIRTi) have been developed to target cancer cell proliferation. Here we provide an overview of methods to study SIRT-dependent cell metabolism and mitochondrial functionality. The chapter describes metabolic flux analysis using Seahorse analyzers, methods for normalization of Seahorse data, flow cytometry and fluorescence microscopy to determine the mitochondrial membrane potential, mitochondrial content per cell and mitochondrial network structures, and Western blot analysis to measure mitochondrial proteins.


Assuntos
Sirtuínas , Sirtuínas/metabolismo , Lisina/metabolismo , Filogenia , Acetilação , Histona Desacetilases/metabolismo , Histona Acetiltransferases/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Inibidores de Histona Desacetilases/farmacologia
3.
Methods Mol Biol ; 2589: 361-376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36255637

RESUMO

Experiments determining the chromatin association of histone acetylases (HATs) and deacetylases (HDACs) at the genome-wide level provide precise maps of locus occupancy, but do not allow conclusions on the functional consequences of this locus-specific enrichment. Here we describe a protocol that allows tethering of HATs or HDACs to specific genomic loci upon fusion with a fluorescent protein and a DNA-binding protein such as the E. coli Lac repressor (LacI), which binds to genomically inserted lac operon sequences (lacO) via DNA/protein interactions. Integration of these lacO sequences into a genomic region of interest allows to monitor the functional consequences of HAT/HDAC targeting on chromatin (de)compaction, histone modification, and interaction with other proteins by quantitative light microscopy, as described here. As DNA-binding of LacI can be tightly controlled by the addition of galactose-derivatives, this method also allows to monitor the effects of locus-specific recruitment in a time-resolved manner.


Assuntos
Cromatina , Histona Acetiltransferases , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Cromatina/genética , Repressores Lac/genética , Histonas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Galactose , Histona Desacetilases/metabolismo , DNA/genética , DNA/metabolismo , Acetilação , Acetiltransferases/metabolismo
4.
Dis Model Mech ; 16(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36341679

RESUMO

Pharmacologic strategies that target factors with both pro-apoptotic and anti-proliferative functions in cardiomyocytes (CMs) may be useful for the treatment of ischemic heart disease. One such multifunctional candidate for drug targeting is the acetyltransferase Tip60, which is known to acetylate both histone and non-histone protein targets that have been shown in cancer cells to promote apoptosis and to initiate the DNA damage response, thereby limiting cellular expansion. Using a murine model, we recently published findings demonstrating that CM-specific disruption of the Kat5 gene encoding Tip60 markedly protects against the damaging effects of myocardial infarction (MI). In the experiments described here, in lieu of genetic targeting, we administered TH1834, an experimental drug designed to specifically inhibit the acetyltransferase domain of Tip60. We report that, similar to the effect of disrupting the Kat5 gene, daily systemic administration of TH1834 beginning 3 days after induction of MI and continuing for 2 weeks of a 4-week timeline resulted in improved systolic function, reduced apoptosis and scarring, and increased activation of the CM cell cycle, effects accompanied by reduced expression of genes that promote apoptosis and inhibit the cell cycle and reduced levels of CMs exhibiting phosphorylated Atm. These results support the possibility that drugs that inhibit the acetyltransferase activity of Tip60 may be useful agents for the treatment of ischemic heart disease.


Assuntos
Histona Acetiltransferases , Infarto do Miocárdio , Camundongos , Animais , Histona Acetiltransferases/metabolismo , Apoptose , Miócitos Cardíacos/metabolismo , Histonas/metabolismo , Infarto do Miocárdio/tratamento farmacológico
5.
Subcell Biochem ; 100: 115-141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36301493

RESUMO

The accurate repair of genomic damage mediated by ionizing radiation (IR), chemo- or radiomimetic drugs, or other exogenous agents, is necessary for maintenance of genome integrity, preservation of cellular viability and prevention of oncogenic transformation. Eukaryotes have conserved mechanisms designed to perceive and repair the damaged DNA quite efficiently. Among the different types of DNA damage, double strand breaks (DSB) are the most detrimental. The cellular DNA DSB response is a hierarchical signaling network that integrates damage sensing and repair with chromatin structural changes that involve a range of pre-existing and induced covalent modifications. Recent studies have revealed that pre-existing histone modifications are important contributors within this signaling/repair network. This chapter discusses the role of a critical histone acetyl transferase (HAT) known as MOF (males absent on the first) and the histone deacetylases (HDACs) Sirtuins on histone H4K16 acetylation (H4K16ac) and DNA damage repair. We also discuss the role of this important histone modification in light of metabolic rewiring and its role in regulating human pathophysiologic states.


Assuntos
Envelhecimento , Histona Acetiltransferases , Neoplasias , Sirtuínas , Humanos , Acetilação , Cromatina , DNA/metabolismo , Dano ao DNA , Reparo do DNA , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Histonas/metabolismo , Neoplasias/genética , Sirtuínas/genética , Sirtuínas/metabolismo
6.
Exp Cell Res ; 421(1): 113375, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36208716

RESUMO

MRG domain binding protein (MRGBP) has been proposed to participate in the development of multiple tumors. However, the role of MRGBP in colorectal cancer (CRC) still remains largely unknown. Here, we found that MRGBP expression is significantly elevated in CRC, and that higher MRGBP expression correlates with poorer survival in CRC patients. Experiments in vivo and in vitro indicated that MRGBP promotes CRC cells proliferation, migration, invasion, epithelial-mesenchymal transition (EMT) and xenograft tumor growth. Mechanically, for one thing, we discovered that MRGBP suppresses DKK1 expression, thus further activating the Wnt/ß-catenin pathway in CRC cells. For another, MRGBP also enhances acetylation of NF-kB/p65 pathway. Treatment with Wnt/ß-catenin and NF-kB pathways inhibitors further confirmed the mediation of these two pathways in MRGBP-promoted CRC cell processes. In conclusion, these findings together suggest that MRGBP promotes CRC progression via DKK1/Wnt/ß-catenin and NF-kB/p65 pathways mediated EMT, identifying MRGBP as a promising prognostic and therapeutic target for CRC.


Assuntos
Neoplasias Colorretais , Transição Epitelial-Mesenquimal , Histona Acetiltransferases , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metástase Neoplásica , NF-kappa B/genética , NF-kappa B/metabolismo , Via de Sinalização Wnt/genética , Proteínas Nucleares/metabolismo , Histona Acetiltransferases/metabolismo
7.
Elife ; 112022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36263929

RESUMO

The NuA4 protein complex acetylates histones H4 and H2A to activate both transcription and DNA repair. We report the 3.1-Å resolution cryo-electron microscopy structure of the central hub of NuA4, which flexibly tethers the histone acetyltransferase (HAT) and Trimer Independent of NuA4 involved in Transcription Interactions with Nucleosomes (TINTIN) modules. The hub contains the large Tra1 subunit and a core that includes Swc4, Arp4, Act1, Eaf1, and the C-terminal region of Epl1. Eaf1 stands out as the primary scaffolding factor that interacts with the Tra1, Swc4, and Epl1 subunits and contributes the conserved HSA helix to the Arp module. Using nucleosome-binding assays, we find that the HAT module, which is anchored to the core through Epl1, recognizes H3K4me3 nucleosomes with hyperacetylated H3 tails, while the TINTIN module, anchored to the core via Eaf1, recognizes nucleosomes that have hyperacetylated H2A and H4 tails. Together with the known interaction of Tra1 with site-specific transcription factors, our data suggest a model in which Tra1 recruits NuA4 to specific genomic sites then allowing the flexible HAT and TINTIN modules to select nearby nucleosomes for acetylation.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Nucleossomos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Microscopia Crioeletrônica , Histona Acetiltransferases/metabolismo , Acetilação
8.
Nat Commun ; 13(1): 6202, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261421

RESUMO

Glioma stem cells (GSC) exhibit plasticity in response to environmental and therapeutic stress leading to tumor recurrence, but the underlying mechanisms remain largely unknown. Here, we employ single-cell and whole transcriptomic analyses to uncover that radiation induces a dynamic shift in functional states of glioma cells allowing for acquisition of vascular endothelial-like and pericyte-like cell phenotypes. These vascular-like cells provide trophic support to promote proliferation of tumor cells, and their selective depletion results in reduced tumor growth post-treatment in vivo. Mechanistically, the acquisition of vascular-like phenotype is driven by increased chromatin accessibility and H3K27 acetylation in specific vascular genes allowing for their increased expression post-treatment. Blocking P300 histone acetyltransferase activity reverses the epigenetic changes induced by radiation and inhibits the adaptive conversion of GSC into vascular-like cells and tumor growth. Our findings highlight a role for P300 in radiation-induced stress response, suggesting a therapeutic approach to prevent glioma recurrence.


Assuntos
Glioma , Recidiva Local de Neoplasia , Humanos , Recidiva Local de Neoplasia/patologia , Glioma/genética , Glioma/radioterapia , Glioma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Cromatina/metabolismo , Histona Acetiltransferases/metabolismo
9.
Pharmacol Res ; 185: 106487, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36202184

RESUMO

Alterations in histone modification have been linked to cancer development and progression. Celastrol, a Chinese herbal compound, shows potent anti-tumor effects through multiple signaling pathways. However, the involvement of histone modifications in this process has not yet been illustrated. In this study, barcode sequencing of a eukaryotic genome-wide deletion library revealed that histone modifications, especially histone acetylation associated with the NuA4 histone acetyltransferase complex, were involved in the anti-proliferation actions of celastrol. The essential roles of histone modification were verified by celastrol sensitivity tests in cells lacking specific genes, such as genes encoding the subunits of the NuA4 and Swr1 complex. The combination of celastrol and histone deacetylase inhibitors (HDACi), rather than the combination of celastrol and histone acetyltransferase inhibitors, synergistically suppressed cancer cell proliferation. In addition to upregulating H4K16 acetylation (H4K16ac), celastrol regulates H3K4 tri-methylation and H3S10 phosphorylation. Celastrol treatment significantly enhanced the suppressive effects of HDACi on lung cancer cell allografts in mice, with significant H4K16ac upregulation, indicating that a combination of celastrol and HDACi is a potential novel therapeutic approach for patients with lung cancer.


Assuntos
Inibidores de Histona Desacetilases , Neoplasias Pulmonares , Camundongos , Animais , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Acetilação , Histonas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Histona Acetiltransferases/metabolismo , Histona Acetiltransferases/uso terapêutico
10.
Exp Parasitol ; 242: 108396, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36228701

RESUMO

Chromatin modification through histone acetylation/deacetylation is important for the regulation of transcription as well as DNA replication in eukaryotes. PfGCN5 and PfMYST are two well-studied histone acetyltransferases in Plasmodium. PfMYST containing the MYST domain, zinc finger domain, and the chromodomain primarily acetylates histone 4. Here, we show that PfMYST is expressed in two isoforms, a long version (∼72 kDa) and a short version (∼45 kDa) of the protein, while the shorter version is predominantly present in the nucleus. Further, the association of PfMYST with the putative Plasmodium autonomously replicating sequences (PfARS) was found to be much stronger than the binding of PfGCN5 in these regions with concomitant enrichment of the H4 acetylation level. The binding of PfMYST at these sites was also correlated with another replication protein PfORC1 as well as with the replicating stage (trophozoite) of the parasite. Collectively these results show for the first time the potential role of PfMYST in parasite DNA replication through chromatin modification that may be found useful for the intervention of parasite growth.


Assuntos
Plasmodium falciparum , Proteínas de Protozoários , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Histonas/metabolismo , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Cromatina , Replicação do DNA
11.
Nature ; 610(7932): 569-574, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36198799

RESUMO

Deoxyribonucleic acid in eukaryotes wraps around the histone octamer to form nucleosomes1, the fundamental unit of chromatin. The N termini of histone H4 interact with nearby nucleosomes and play an important role in the formation of high-order chromatin structure and heterochromatin silencing2-4. NuA4 in yeast and its homologue Tip60 complex in mammalian cells are the key enzymes that catalyse H4 acetylation, which in turn regulates chromatin packaging and function in transcription activation and DNA repair5-10. Here we report the cryo-electron microscopy structure of NuA4 from Saccharomyces cerevisiae bound to the nucleosome. NuA4 comprises two major modules: the catalytic histone acetyltransferase (HAT) module and the transcription activator-binding (TRA) module. The nucleosome is mainly bound by the HAT module and is positioned close to a polybasic surface of the TRA module, which is important for the optimal activity of NuA4. The nucleosomal linker DNA carrying the upstream activation sequence is oriented towards the conserved, transcription activator-binding surface of the Tra1 subunit, which suggests a potential mechanism of NuA4 to act as a transcription co-activator. The HAT module recognizes the disk face of the nucleosome through the H2A-H2B acidic patch and nucleosomal DNA, projecting the catalytic pocket of Esa1 to the N-terminal tail of H4 and supporting its function in selective acetylation of H4. Together, our findings illustrate how NuA4 is assembled and provide mechanistic insights into nucleosome recognition and transcription co-activation by a HAT.


Assuntos
Microscopia Crioeletrônica , Histona Acetiltransferases , Nucleossomos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Animais , Acetilação , DNA/química , DNA/metabolismo , DNA/ultraestrutura , Histona Acetiltransferases/química , Histona Acetiltransferases/metabolismo , Histona Acetiltransferases/ultraestrutura , Histonas/química , Histonas/metabolismo , Histonas/ultraestrutura , Nucleossomos/química , Nucleossomos/metabolismo , Nucleossomos/ultraestrutura , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/ultraestrutura , Fatores de Transcrição/metabolismo
12.
Mol Cell Biol ; 42(11): e0017022, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36190236

RESUMO

Trimer Independent of NuA4 involved in Transcription Interactions with Nucleosomes (TINTIN) is an integral module of the essential yeast lysine acetyltransferase complex NuA4 that plays key roles in transcription regulation and DNA repair. Composed of Eaf3, Eaf5, and Eaf7, TINTIN mediates targeting of NuA4 to chromatin through the chromodomain-containing subunit Eaf3 that is shared with the Rpd3S histone deacetylase complex. How Eaf3 mediates chromatin interaction in the context of TINTIN and how is it different from what has been observed in Rpd3S is unclear. Here, we reconstituted recombinant TINTIN and its subassemblies and characterized their biochemical and structural properties. Our coimmunoprecipitation, AlphaFold2 modeling, and hydrogen deuterium exchange mass spectrometry (HDX-MS) analyses revealed that the Eaf3 MRG domain contacts Eaf7 and this binding induces conformational changes throughout Eaf3. Nucleosome-binding assays showed that Eaf3 and TINTIN interact non-specifically with the DNA on nucleosomes. Furthermore, integration into TINTIN enhances the affinity of Eaf3 toward nucleosomes and this improvement is a result of allosteric activation of the Eaf3 chromodomain. Negative stain electron microscopy (EM) analysis revealed that TINTIN binds to the edge of nucleosomes with increased specificity in the presence of H3K36me3. Collectively, our work provides insights into the dynamics of TINTIN and the mechanism by which its interactions with chromatin are regulated.


Assuntos
Nucleossomos , Proteínas de Saccharomyces cerevisiae , Nucleossomos/metabolismo , Regulação Alostérica , Proteínas de Saccharomyces cerevisiae/metabolismo , Histonas/metabolismo , Acetiltransferases/química , Saccharomyces cerevisiae/metabolismo , Cromatina/metabolismo , Histona Acetiltransferases/metabolismo
13.
Genes Dev ; 36(17-18): 985-1001, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36302553

RESUMO

Genome-wide, little is understood about how proteins organize at inducible promoters before and after induction and to what extent inducible and constitutive architectures depend on cofactors. We report that sequence-specific transcription factors and their tethered cofactors (e.g., SAGA [Spt-Ada-Gcn5-acetyltransferase], Mediator, TUP, NuA4, SWI/SNF, and RPD3-L) are generally bound to promoters prior to induction ("poised"), rather than recruited upon induction, whereas induction recruits the preinitiation complex (PIC) to DNA. Through depletion and/or deletion experiments, we show that SAGA does not function at constitutive promoters, although a SAGA-independent Gcn5 acetylates +1 nucleosomes there. When inducible promoters are poised, SAGA catalyzes +1 nucleosome acetylation but not PIC assembly. When induced, SAGA catalyzes acetylation, deubiquitylation, and PIC assembly. Surprisingly, SAGA mediates induction by creating a PIC that allows TFIID (transcription factor II-D) to stably associate, rather than creating a completely TFIID-independent PIC, as generally thought. These findings suggest that inducible systems, where present, are integrated with constitutive systems.


Assuntos
Proteínas de Saccharomyces cerevisiae , Fator de Transcrição TFIID , Fator de Transcrição TFIID/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transativadores/genética , Transativadores/metabolismo , Regiões Promotoras Genéticas/genética , Nucleossomos/genética , Nucleossomos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo
14.
Aging (Albany NY) ; 14(20): 8292-8301, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36309909

RESUMO

α-synuclein (αS) is a ß-sheet intracellular protein that has been implicated as a major pathological hallmark of Parkinson's disease (PD). Several studies have shown that overexpression of αS causes dopaminergic cell loss; however, the role of αS in apoptosis remains not fully known. Therefore, this study aims to address the mechanisms of the αS overexpression model in apoptosis and to its correlation with PD pathogenesis. Here, we used a human αS (hαS) plasmid to characterize the role of ectopic αS in neuronal apoptosis in sporadic PD in vitro. We found that overexpression of αS transcriptionally upregulated Bim-mediated apoptosis in neuronal SH-SY5Y cells. Interestingly, αS overexpression inhibited general control non-depressible 5 (GCN5), a histone acetyltransferase (HAT), and promoted transcriptional upregulation of Bim. Consequently, co-overexpression of GCN5 in the αS overexpressed model showed a reversal of αS toxicity in neuronal cells. These in vitro findings support the hypothesis of αS-mediated histone deacetylation and dopaminergic neuronal loss in PD. Moreover, our study indicates that therapeutic activation/homeostasis of GCN5 may benefit PD and other α-synucleinopathies.


Assuntos
Neuroblastoma , Doença de Parkinson , Humanos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Apoptose/genética , Proteína 11 Semelhante a Bcl-2/metabolismo , Neurônios Dopaminérgicos/metabolismo , Histona Acetiltransferases/metabolismo , Doença de Parkinson/metabolismo
15.
Genetics ; 222(3)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36066422

RESUMO

The NuA4 lysine acetyltransferase complex acetylates histone and nonhistone proteins and functions in transcription regulation, cell cycle progression, and DNA repair. NuA4 harbors an interesting duality in that its catalytic module can function independently and distinctly as picNuA4. At the molecular level, picNuA4 anchors to its bigger brother via physical interactions between the C-terminus of Epl1 and the HSA domain of Eaf1, the NuA4 central scaffolding subunit. This is reflected at the regulatory level, as picNuA4 can be liberated genetically from NuA4 by disrupting the Epl1-Eaf1 interaction. As such, removal of either Eaf1 or the Epl1 C-terminus offers a unique opportunity to elucidate the contributions of Eaf1 and Epl1 to NuA4 biology and in turn their roles in balancing picNuA4 and NuA4 activities. Using high-throughput genetic and gene expression profiling, and targeted functional assays to compare eaf1Δ and epl1-CΔ mutants, we found that EAF1 and EPL1 had both overlapping and distinct roles. Strikingly, loss of EAF1 or its HSA domain led to a significant decrease in the amount of picNuA4, while loss of the Epl1 C-terminus increased picNuA4 levels, suggesting starkly opposing effects on picNuA4 regulation. The eaf1Δ epl1-CΔ double mutants resembled the epl1-CΔ single mutants, indicating that Eaf1's role in picNuA4 regulation depended on the Epl1 C-terminus. Key aspects of this regulation were evolutionarily conserved, as truncating an Epl1 homolog in human cells increased the levels of other picNuA4 subunits. Our findings suggested a model in which distinct aspects of the Epl1-Eaf1 interaction regulated picNuA4 amount and activity.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Acetilação , Histonas/metabolismo , Fatores de Transcrição/metabolismo
16.
J Neurosci ; 42(42): 7984-8001, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36109165

RESUMO

Environmental factors and life experiences impinge on brain circuits triggering adaptive changes. Epigenetic regulators contribute to this neuroadaptation by enhancing or suppressing specific gene programs. The paralogous transcriptional coactivators and lysine acetyltransferases CREB binding protein (CBP) and p300 are involved in brain plasticity and stimulus-dependent transcription, but their specific roles in neuroadaptation are not fully understood. Here we investigated the impact of eliminating either CBP or p300 in excitatory neurons of the adult forebrain of mice from both sexes using inducible and cell type-restricted knock-out strains. The elimination of CBP, but not p300, reduced the expression and chromatin acetylation of plasticity genes, dampened activity-driven transcription, and caused memory deficits. The defects became more prominent in elderly mice and in paradigms that involved enduring changes in transcription, such as kindling and environmental enrichment, in which CBP loss interfered with the establishment of activity-induced transcriptional and epigenetic changes in response to stimulus or experience. These findings further strengthen the link between CBP deficiency in excitatory neurons and etiopathology in the nervous system.SIGNIFICANCE STATEMENT How environmental conditions and life experiences impinge on mature brain circuits to elicit adaptive responses that favor the survival of the organism remains an outstanding question in neurosciences. Epigenetic regulators are thought to contribute to neuroadaptation by initiating or enhancing adaptive gene programs. In this article, we examined the role of CREB binding protein (CBP) and p300, two paralogous transcriptional coactivators and histone acetyltransferases involved in cognitive processes and intellectual disability, in neuroadaptation in adult hippocampal circuits. Our experiments demonstrate that CBP, but not its paralog p300, plays a highly specific role in the epigenetic regulation of neuronal plasticity gene programs in response to stimulus and provide unprecedented insight into the molecular mechanisms underlying neuroadaptation.


Assuntos
Proteína de Ligação a CREB , Epigênese Genética , Masculino , Feminino , Camundongos , Animais , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/metabolismo , Histonas/metabolismo , Histona Acetiltransferases/metabolismo , Acetilação , Fatores de Transcrição/metabolismo , Cromatina/metabolismo , Hipocampo/metabolismo , Fatores de Transcrição de p300-CBP/genética , Fatores de Transcrição de p300-CBP/metabolismo
17.
Front Endocrinol (Lausanne) ; 13: 886594, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060957

RESUMO

The development and growth of a normal prostate gland, as well as its physiological functions, are regulated by the actions of androgens through androgen receptor (AR) signaling which drives multiple cellular processes including transcription, cellular proliferation, and apoptosis in prostate cells. Post-translational regulation of AR plays a vital role in directing its cellular activities via modulating its stability, nuclear localization, and transcriptional activity. Among various post-translational modifications (PTMs), acetylation is an essential PTM recognized in AR and is governed by the regulated actions of acetyltransferases and deacetyltransferases. Acetylation of AR has been identified as a critical step for its activation and depending on the site of acetylation, the intracellular dynamics and activity of the AR can be modulated. Various acetyltransferases such as CBP, p300, PCAF, TIP60, and ARD1 that are known to acetylate AR, may directly coactivate the AR transcriptional function or help to recruit additional coactivators to functionally regulate the transcriptional activity of the AR. Aberrant expression of acetyltransferases and their deregulated activities have been found to interfere with AR signaling and play a key role in development and progression of prostatic diseases, including prostate cancer (PCa). In this review, we summarized recent research advances aimed at understanding the role of various lysine acetyltransferases (KATs) in the regulation of AR activity at the level of post-translational modifications in normal prostate physiology, as well as in development and progression of PCa. Considering the critical importance of KATs in modulating AR activity in physiological and patho-physiological context, we further discussed the potential of targeting these enzymes as a therapeutic option to treat AR-related pathology in combination with hormonal therapy.


Assuntos
Lisina Acetiltransferases , Neoplasias da Próstata , Receptores Androgênicos , Acetilação , Androgênios , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Humanos , Lisina Acetiltransferases/metabolismo , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
18.
Int J Mol Sci ; 23(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36142359

RESUMO

Histone acetyltransferases (HATs) are involved in the epigenetic positive control of gene expression in eukaryotes. CREB-binding proteins (CBP)/p300, a subfamily of highly conserved HATs, have been shown to function as acetylases on both histones and non-histone proteins. In the model plant Arabidopsis thaliana among the five CBP/p300 HATs, HAC1, HAC5 and HAC12 have been shown to be involved in the ethylene signaling pathway. In addition, HAC1 and HAC5 interact and cooperate with the Mediator complex, as in humans. Therefore, it is potentially difficult to discriminate the effect on plant development of the enzymatic activity with respect to their Mediator-related function. Taking advantage of the homology of the human HAC catalytic domain with that of the Arabidopsis, we set-up a phenotypic assay based on the hypocotyl length of Arabidopsis dark-grown seedlings to evaluate the effects of a compound previously described as human p300/CBP inhibitor, and to screen previously described cinnamoyl derivatives as well as newly synthesized analogues. We selected the most effective compounds, and we demonstrated their efficacy at phenotypic and molecular level. The in vitro inhibition of the enzymatic activity proved the specificity of the inhibitor on the catalytic domain of HAC1, thus substantiating this strategy as a useful tool in plant epigenetic studies.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Acetilação , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arseniato Redutases/metabolismo , Proteína de Ligação a CREB/metabolismo , Etilenos/metabolismo , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Humanos , Complexo Mediador/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo
19.
Front Endocrinol (Lausanne) ; 13: 972312, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36171897

RESUMO

Protein acetylation is a reversible post-translational modification, and is involved in many biological processes in cells, such as transcriptional regulation, DNA damage repair, and energy metabolism, which is an important molecular event and is associated with a wide range of diseases such as cancers. Protein acetylation is dynamically regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs) in homeostasis. The abnormal acetylation level might lead to the occurrence and deterioration of a cancer, and is closely related to various pathophysiological characteristics of a cancer, such as malignant phenotypes, and promotes cancer cells to adapt to tumor microenvironment. Therapeutic modalities targeting protein acetylation are a potential therapeutic strategy. This article discussed the roles of protein acetylation in tumor pathology and therapeutic drugs targeting protein acetylation, which offers the contributions of protein acetylation in clarification of carcinogenesis, and discovery of therapeutic drugs for cancers, and lays the foundation for precision medicine in oncology.


Assuntos
Histona Acetiltransferases , Neoplasias , Acetilação , Carcinogênese , Descoberta de Drogas , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Histona Acetiltransferases/uso terapêutico , Histona Desacetilases/genética , Humanos , Neoplasias/tratamento farmacológico , Processamento de Proteína Pós-Traducional , Microambiente Tumoral
20.
Int J Clin Oncol ; 27(11): 1684-1697, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35976474

RESUMO

OBJECTIVE: To explore the effect and mechanism of the miR-339-3p/KAT6A/TRIM24 axis in nasopharyngeal carcinoma (NPC) cell growth and epithelial-mesenchymal transition (EMT) progression. METHODS: CNE2 and 5-8F NPC cell lines were transfected with miR-339-3p-mimic or sh-KAT6A alone or co-transfected with miR-339-3p-mimic and oe-KAT6A. The expression levels of miR-339-3p, KAT6A, TRIM24, and EMT-related proteins were assessed, in addition to cell biological behaviors. Then, the relationship between miR-339-3p and KAT6A was predicted and validated. The correlations between miR-339-3p and KAT6A or between KAT6A and TRIM24 were analyzed by Pearson coefficient and the enrichment of H3K23ac in TRIM24 promoter region was measured by chromatin immunoprecipitation. RESULTS: miR-339-3p was downregulated, but KAT6A and TRIM24 were highly expressed in NPC cells and tissues. Upregulated miR-339-3p or downregulated KAT6A could inhibit the growth and EMT of NPC cells. Further experiments showed that miR-339-3p regulated NPC cell growth and EMT by mediating KAT6A in a targeted fashion. KAT6A was positively correlated with TRIM24, and the enrichment of H3K23ac was much higher in NPC tissues. miR-339-3p suppressed the growth and EMT of NPC cells by the KAT6A/TRIM24 axis. In a xenograft study, miR-339-3p overexpression inhibited NPC tumor growth in vivo. CONCLUSION: Conclusively, miR-339-3p inhibited the growth and EMT of NPC cells via the KAT6A/TRIM24 axis.


Assuntos
Proteínas de Transporte , Histona Acetiltransferases , MicroRNAs , Neoplasias Nasofaríngeas , Humanos , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Histona Acetiltransferases/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Animais
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