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1.
PLoS One ; 15(9): e0238477, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32877461

RESUMO

Somatic copy number alterations (CNA) are common in endometrial serous carcinoma (ESC). We used the Tumor Cancer Genome Atlas Pan Cancer dataset (TCGA Pan Can) to explore the impact of somatic CNA and gene expression levels (mRNA) of cancer-related genes in ESC. Results were correlated with clinico-pathologic parameters such as age of onset, disease stage, progression-free survival (PFS) and overall survival (OS) (n = 108). 1,449 genes with recurrent somatic CNA were identified, observed in 10% or more tumor samples. Somatic CNA and mRNA expression levels were highly correlated (r> = 0.6) for 383 genes. Among these, 45 genes were classified in the Tier 1 category of Cancer Genome Census-Catalogue of Somatic Mutations in Cancer. Eighteen of 45 Tier 1 genes had highly correlated somatic CNA and mRNA expression levels including ARNT, PIK3CA, TBLXR1, ASXL1, EIF4A2, HOOK3, IKBKB, KAT6A, TCEA1, KAT6B, ERBB2, BRD4, KEAP1, PRKACA, DNM2, SMARCA4, AKT2, SS18L1. Our results are in agreement with previously reported somatic CNA for ERBB2, BRD4 and PIK3C in ESC. In addition, AKT2 (p = 0.002) and KAT6A (p = 0.015) amplifications were more frequent in tumor samples from younger patients (<60), and CEBPA (p = 0.028) and MYC (p = 0.023) amplifications were more common with advanced (stage III and IV) disease stage. Patients with tumors carrying KAT6A and MYC amplifications had shorter PFS and OS. The hazard ratio (HR) of KAT6A was 2.82 [95 CI 1.12-7.07] for PFS and 3.87 [95 CI 1.28-11.68] for OS. The HR of MYC was 2.25 [95 CI 1.05-4.81] and 2.62[95 CI 1.07-6.41] for PFS and OS, respectively.


Assuntos
Neoplasias do Endométrio/genética , Histona Acetiltransferases/genética , Biomarcadores Tumorais/genética , Classe I de Fosfatidilinositol 3-Quinases , Cistadenocarcinoma Seroso/genética , Variações do Número de Cópias de DNA/genética , DNA Helicases , Bases de Dados Genéticas , Intervalo Livre de Doença , Neoplasias do Endométrio/patologia , Feminino , Perfilação da Expressão Gênica/métodos , Histona Acetiltransferases/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch , Mutação , Fator 2 Relacionado a NF-E2 , Proteínas Nucleares/genética , Oncogenes , Neoplasias Ovarianas/patologia , Prognóstico , Intervalo Livre de Progressão , Fatores de Transcrição , Transcriptoma/genética
2.
Mol Cell Biol ; 40(18)2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32661120

RESUMO

The DNA and protein complex known as chromatin is subject to posttranslational modifications (PTMs) that regulate cellular functions such that PTM dysregulation can lead to disease, including cancer. One critical PTM is acetylation/deacetylation, which is being investigated as a means to develop targeted cancer therapies. The histone acetyltransferase (HAT) family of proteins performs histone acetylation. In humans, MOF (hMOF), a member of the MYST family of HATs, acetylates histone H4 at lysine 16 (H4K16ac). MOF-mediated acetylation plays a critical role in the DNA damage response (DDR) and embryonic stem cell development. Functionally, MOF is found in two distinct complexes: NSL (nonspecific lethal) in humans and MSL (male-specific lethal) in flies. The NSL complex is also able to acetylate additional histone H4 sites. Dysregulation of MOF activity occurs in multiple cancers, including ovarian cancer, medulloblastoma, breast cancer, colorectal cancer, and lung cancer. Bioinformatics analysis of KAT8, the gene encoding hMOF, indicated that it is highly overexpressed in kidney tumors as part of a concerted gene coexpression program that can support high levels of chromosome segregation and cell proliferation. The linkage between MOF and tumor proliferation suggests that there are additional functions of MOF that remain to be discovered.


Assuntos
Dano ao DNA , Células-Tronco Embrionárias/citologia , Histona Acetiltransferases/metabolismo , Acetilação , Carcinogênese/metabolismo , Diferenciação Celular/fisiologia , Núcleo Celular/metabolismo , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/metabolismo , Cromatina/metabolismo , Células-Tronco Embrionárias/metabolismo , Células-Tronco Embrionárias/fisiologia , Histonas/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas Nucleares/metabolismo , Processamento de Proteína Pós-Traducional
3.
Nucleic Acids Res ; 48(14): 7899-7913, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32609816

RESUMO

In the Elongator-dependent modification pathway, chemical modifications are introduced at the wobble uridines at position 34 in transfer RNAs (tRNAs), which serve to optimize codon translation rates. Here, we show that this three-step modification pathway exists in Dictyostelium discoideum, model of the evolutionary superfamily Amoebozoa. Not only are previously established modifications observable by mass spectrometry in strains with the most conserved genes of each step deleted, but also additional modifications are detected, indicating a certain plasticity of the pathway in the amoeba. Unlike described for yeast, D. discoideum allows for an unconditional deletion of the single tQCUG gene, as long as the Elongator-dependent modification pathway is intact. In gene deletion strains of the modification pathway, protein amounts are significantly reduced as shown by flow cytometry and Western blotting, using strains expressing different glutamine leader constructs fused to GFP. Most dramatic are these effects, when the tQCUG gene is deleted, or Elp3, the catalytic component of the Elongator complex is missing. In addition, Elp3 is the most strongly conserved protein of the modification pathway, as our phylogenetic analysis reveals. The implications of this observation are discussed with respect to the evolutionary age of the components acting in the Elongator-dependent modification pathway.


Assuntos
Dictyostelium/genética , RNA de Transferência/metabolismo , Anticódon/química , Anticódon/metabolismo , Códon , Dictyostelium/metabolismo , Deleção de Genes , Glutamina , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Mutação , Nucleosídeos/química , Filogenia , Biossíntese de Proteínas , Proteínas de Protozoários/classificação , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Uridina/metabolismo
4.
Mol Cell Endocrinol ; 515: 110917, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32593740

RESUMO

Obesity patients are more susceptible to develop COVID-19 severe outcome due to the role of angiotensin-converting enzyme 2 (ACE2) in the viral infection. ACE2 is regulated in the human cells by different genes associated with increased (TLR3, HAT1, HDAC2, KDM5B, SIRT1, RAB1A, FURIN and ADAM10) or decreased (TRIB3) virus replication. RNA-seq data revealed 14857 genes expressed in human subcutaneous adipocytes, including genes mentioned above. Irisin treatment increased by 3-fold the levels of TRIB3 transcript and decreased the levels of other genes. The decrease in FURIN and ADAM10 expression enriched diverse biological processes, including extracellular structure organization. Our results, in human subcutaneous adipocytes cell culture, indicate a positive effect of irisin on the expression of multiple genes related to viral infection by SARS-CoV-2; furthermore, translatable for other tissues and organs targeted by the novel coronavirus and present, thus, promising approaches for the treatment of COVID-19 infection as therapeutic strategy to decrease ACE2 regulatory genes.


Assuntos
Adipócitos/efeitos dos fármacos , Fibronectinas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína ADAM10/genética , Proteína ADAM10/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Betacoronavirus/genética , Betacoronavirus/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Infecções por Coronavirus/virologia , Fibronectinas/genética , Fibronectinas/metabolismo , Furina/genética , Furina/metabolismo , Ontologia Genética , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Biológicos , Anotação de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Obesidade/virologia , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/virologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo , Proteínas rab1 de Ligação ao GTP/genética , Proteínas rab1 de Ligação ao GTP/metabolismo
5.
PLoS Genet ; 16(5): e1008770, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32453730

RESUMO

Hormone-dependent activation of enhancers includes histone hyperacetylation and mediator recruitment. Histone hyperacetylation is mostly explained by a bimodal switch model, where histone deacetylases (HDACs) disassociate from chromatin, and histone acetyl transferases (HATs) are recruited. This model builds on decades of research on steroid receptor regulation of transcription. Yet, the general concept of the bimodal switch model has not been rigorously tested genome wide. We have used a genomics approach to study enhancer hyperacetylation by the thyroid hormone receptor (TR), described to operate as a bimodal switch. H3 acetylation, HAT and HDAC ChIP-seq analyses of livers from hypo- and hyperthyroid wildtype, TR deficient and NCOR1 disrupted mice reveal three types of thyroid hormone (T3)-regulated enhancers. One subset of enhancers is bound by HDAC3-NCOR1 in the absence of hormone and constitutively occupy TR and HATs irrespective of T3 levels, suggesting a poised enhancer state in absence of hormone. In presence of T3, HDAC3-NCOR1 dissociates from these enhancers leading to histone hyperacetylation, suggesting a histone acetylation rheostat function of HDACs at poised enhancers. Another subset of enhancers, not occupied by HDACs, is hyperacetylated in a T3-dependent manner, where TR is recruited to chromatin together with HATs. Lastly, a subset of enhancers, is not occupied directly by TR yet requires TR for histone hyperacetylation. This indirect enhancer activation involves co-association with TR bound enhancers within super-enhancers or topological associated domains. Collectively, this demonstrates various mechanisms controlling hormone-dependent transcription and adds significant details to the otherwise simple bimodal switch model.


Assuntos
Elementos Facilitadores Genéticos/efeitos dos fármacos , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Receptores dos Hormônios Tireóideos/genética , Hormônios Tireóideos/farmacologia , Acetilação , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Histona Desacetilases/metabolismo , Fígado/química , Masculino , Camundongos , Correpressor 1 de Receptor Nuclear/genética , Correpressor 1 de Receptor Nuclear/metabolismo
6.
Nucleic Acids Res ; 48(11): 5953-5966, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32396165

RESUMO

The modification of histones by acetyl groups has a key role in the regulation of chromatin structure and transcription. The Arabidopsis thaliana histone acetyltransferase GCN5 regulates histone modifications as part of the Spt-Ada-Gcn5 Acetyltransferase (SAGA) transcriptional coactivator complex. GCN5 was previously shown to acetylate lysine 14 of histone 3 (H3K14ac) in the promoter regions of its target genes even though GCN5 binding did not systematically correlate with gene activation. Here, we explored the mechanism through which GCN5 controls transcription. First, we fine-mapped its GCN5 binding sites genome-wide and then used several global methodologies (ATAC-seq, ChIP-seq and RNA-seq) to assess the effect of GCN5 loss-of-function on the expression and epigenetic regulation of its target genes. These analyses provided evidence that GCN5 has a dual role in the regulation of H3K14ac levels in their 5' and 3' ends of its target genes. While the gcn5 mutation led to a genome-wide decrease of H3K14ac in the 5' end of the GCN5 down-regulated targets, it also led to an increase of H3K14ac in the 3' ends of GCN5 up-regulated targets. Furthermore, genome-wide changes in H3K14ac levels in the gcn5 mutant correlated with changes in H3K9ac at both 5' and 3' ends, providing evidence for a molecular link between the depositions of these two histone modifications. To understand the biological relevance of these regulations, we showed that GCN5 participates in the responses to biotic stress by repressing salicylic acid (SA) accumulation and SA-mediated immunity, highlighting the role of this protein in the regulation of the crosstalk between diverse developmental and stress-responsive physiological programs. Hence, our results demonstrate that GCN5, through the modulation of H3K14ac levels on its targets, controls the balance between biotic and abiotic stress responses and is a master regulator of plant-environmental interactions.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Homeostase , Lisina/metabolismo , Ácido Salicílico/metabolismo , Regiões 5' não Traduzidas/genética , Acetilação , Arabidopsis/imunologia , Histonas/química , Lisina/química , Imunidade Vegetal/genética , Regiões Promotoras Genéticas/genética , Transcrição Genética
7.
Muscle Nerve ; 62(1): 128-136, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32304242

RESUMO

INTRODUCTION: Emery-Dreifuss muscular dystrophy (EDMD) is a disease characterized by skeletal muscle wasting, major tendon contractures, and cardiac conduction defects. Mutations in the gene encoding emerin cause EDMD1. Our previous studies suggested that emerin activation of histone deacetylase 3 (HDAC3) to reduce histone 4-lysine 5 (H4K5) acetylation (ac) is important for myogenic differentiation. METHODS: Pharmacological inhibitors (Nu9056, L002) of histone acetyltransferases targeting acetylated H4K5 were used to test whether increased acetylated H4K5 was responsible for the impaired differentiation seen in emerin-deficient myogenic progenitors. RESULTS: Nu9056 and L002 rescued impaired differentiation in emerin deficiency. SRT1720, which inhibits the nicotinamide adenine dinucleotide (NAD)+ -dependent deacetylase sirtuin 1 (SIRT1), failed to rescue myotube formation. DISCUSSION: We conclude that emerin regulation of HDAC3 activity to affect H4K5 acetylation dynamics is important for myogenic differentiation. Targeting H4K5ac dynamics represents a potential new strategy for ameliorating the skeletal muscle wasting seen in EDMD1.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Histona Acetiltransferases/antagonistas & inibidores , Distrofia Muscular de Emery-Dreifuss/tratamento farmacológico , Distrofia Muscular de Emery-Dreifuss/patologia , Células-Tronco/efeitos dos fármacos , Tiazóis/uso terapêutico , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Histona Acetiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco/patologia , Tiazóis/farmacologia
8.
Nat Commun ; 11(1): 1498, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32198348

RESUMO

Despite histone H2A variants and acetylation of histones occurring in almost every eukaryotic organism, it has been difficult to establish direct functional links between canonical histones or H2A variant acetylation, deposition of H2A variants and transcription. To disentangle these complex interdependent processes, we devised a highly sensitive strategy for quantifying histone acetylation levels at specific genomic loci. Taking advantage of the unusual genome organization in Trypanosoma brucei, we identified 58 histone modifications enriched at transcription start sites (TSSs). Furthermore, we found TSS-associated H4 and H2A.Z acetylation to be mediated by two different histone acetyltransferases, HAT2 and HAT1, respectively. Whereas depletion of HAT2 decreases H2A.Z deposition and shifts the site of transcription initiation, depletion of HAT1 does not affect H2A.Z deposition but reduces total mRNA levels by 50%. Thus, specifically reducing H4 or H2A.Z acetylation levels enabled us to reveal distinct roles for these modifications in H2A.Z deposition and RNA transcription.


Assuntos
Histonas/metabolismo , Processamento de Proteína Pós-Traducional , RNA/metabolismo , Trypanosoma brucei brucei/metabolismo , Acetilação , Linhagem Celular , Genômica , Histona Acetiltransferases/metabolismo , Código das Histonas , Nucleossomos , RNA Mensageiro , Sítio de Iniciação de Transcrição , Transcriptoma , Trypanosoma brucei brucei/genética
9.
Biochem Pharmacol ; 175: 113914, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32173363

RESUMO

Transcriptional coactivators p300 and CBP catalyze the acetylation of lysine residues in histone proteins. Upregulation of p300 and CBP has been associated with lung, colorectal and hepatocellular cancer, indicating an important role of p300 and CBP in tumorigenesis. Recently, the novel p300 and CBP-selective inhibitor A485 became available, which was shown to inhibit proliferation of 124 different cancer cell lines. Here, we found that downregulation of EP300 or CREBBP enhances apoptosis upon TRAIL stimulation in non-small-cell lung cancer (NSCLC) cells. A485 upregulates pro- and anti-apoptotic genes at the mRNA level, implying an apoptosis-modulating effect in NSCLC cells. However, A485 alone does not induce apoptosis. Interestingly, we observed that the number of apoptotic cells increases upon combined treatment with A485 and TRAIL. Therefore, A485, as a TRAIL-sensitizer, was used in combination with TRAIL in wild type of NSCLC cell lines (HCC827 and H1650) and cells with acquired erlotinib resistance (HCC827-ER and H1650-ER). Our results show that the combination of A485 and TRAIL synergistically increases cell death and inhibits long-term cell proliferation. Furthermore, this combination inhibits the growth of 3D spheroids of EGFR-TKI-resistant cells. Taken together, we demonstrate a successful combination of A485 and TRAIL in EGFR-TKI-sensitive and resistant NSCLC cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/enzimologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Inibidores Enzimáticos/administração & dosagem , Histona Acetiltransferases/antagonistas & inibidores , Neoplasias Pulmonares/enzimologia , Ligante Indutor de Apoptose Relacionado a TNF/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Histona Acetiltransferases/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
10.
Zhonghua Gan Zang Bing Za Zhi ; 28(2): 147-151, 2020 Feb 20.
Artigo em Chinês | MEDLINE | ID: mdl-32164066

RESUMO

Objective: To investigate the effect of knockdown of O-GlcNAc transferase (OGT) on hepatocyte fat synthesis. Methods: Liver cell line L02 were used to established the model of hepatic steatosis. The levels of OGT and O-GlcNAc protein were detected by Western blot. The OGT knockdown cell line of L02 cells was established, and its lipid formation ability was detected after induction of oleic acid (OA). Real-time quantitative PCR (qRT-PCR) and Western blot were used to detect mRNA and protein expression of enzymes related to fat synthesis. An independent sample t test was used. Results: Western blot showed that the expression of OGT and O-GlcNAc was increased in L02 cells after adipogenesis (P < 0.05). After shOGT lentivirus infects L02 cells, OGT mRNA levels were down-regulated (P < 0.01). Oil red O staining showed that the lipid in L02 shOGT cells decreased, qRT-PCR showed that the mRNA expressions of fat synthase (ACC1), (FASN) and (SCD1) were decreased, the difference was statistically significant (P < 0.05), protein Expression is consistent with mRNA expression. Conclusion: Knockdown of OGT can inhibit hepatocyte fat synthesis by reducing O-GlcNAc levels.


Assuntos
Antígenos de Neoplasias/metabolismo , Fígado Gorduroso , Hepatócitos/metabolismo , Histona Acetiltransferases/metabolismo , Hialuronoglucosaminidase/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Linhagem Celular , Humanos
11.
Sci Adv ; 6(4): eaax0021, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32010779

RESUMO

Lysine acetyltransferase 6A (KAT6A) and its paralog KAT6B form stoichiometric complexes with bromodomain- and PHD finger-containing protein 1 (BRPF1) for acetylation of histone H3 at lysine 23 (H3K23). We report that these complexes also catalyze H3K23 propionylation in vitro and in vivo. Immunofluorescence microscopy and ATAC-See revealed the association of this modification with active chromatin. Brpf1 deletion obliterates the acylation in mouse embryos and fibroblasts. Moreover, we identify BRPF1 variants in 12 previously unidentified cases of syndromic intellectual disability and demonstrate that these cases and known BRPF1 variants impair H3K23 propionylation. Cardiac anomalies are present in a subset of the cases. H3K23 acylation is also impaired by cancer-derived somatic BRPF1 mutations. Valproate, vorinostat, propionate and butyrate promote H3K23 acylation. These results reveal the dual functionality of BRPF1-KAT6 complexes, shed light on mechanisms underlying related developmental disorders and various cancers, and suggest mutation-based therapy for medical conditions with deficient histone acylation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ligação a DNA/metabolismo , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Neoplasias/etiologia , Neoplasias/metabolismo , Transtornos do Neurodesenvolvimento/etiologia , Transtornos do Neurodesenvolvimento/metabolismo , Acetilação , Proteínas Adaptadoras de Transdução de Sinal/genética , Sequência de Aminoácidos , Animais , Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Linhagem Celular , Análise Mutacional de DNA , Proteínas de Ligação a DNA/genética , Suscetibilidade a Doenças , Predisposição Genética para Doença , Histona Acetiltransferases/genética , Humanos , Imagem por Ressonância Magnética , Camundongos , Camundongos Knockout , Modelos Biológicos , Complexos Multiproteicos/metabolismo , Mutação , Neoplasias/diagnóstico , Transtornos do Neurodesenvolvimento/diagnóstico , Fenótipo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Processamento de Proteína Pós-Traducional , Síndrome
12.
Plant Mol Biol ; 103(1-2): 1-7, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32088831

RESUMO

KEY MESSAGE: The auxin signaling and root morphogenesis are harmoniously controlled by two counteracted teams including (1) auxin/indole-3-acetic acid (AUX/IAA)-histone deacetylase (HDA) and (2) auxin response factor (ARF)-histone acetyltransferase (HAT). The involvement of histone acetylation in the regulation of transcription was firstly reported a few decades ago. In planta, auxin is the first hormone group that was discovered and it is also the most studied phytohormone. Current studies have elucidated the functions of histone acetylation in the modulation of auxin signaling as well as in the regulation of root morphogenesis under both normal and stress conditions. Based on the recent outcomes, this review is to provide a hierarchical view about the functions of histone acetylation in auxin signaling and root morphogenesis. In this report, we suggest that the auxin signaling must be controlled harmoniously by two counteracted teams including (1) auxin/indole-3-acetic acid (AUX/IAA)-histone deacetylase (HDA) and (2) auxin response factor (ARF)-histone acetyltransferase (HAT). Moreover, the balance in auxin signaling is very critical to contribute to normal root morphogenesis.


Assuntos
Histonas/metabolismo , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Acetilação , Histona Acetiltransferases/metabolismo , Histona Desacetilases/metabolismo , Homeostase , Morfogênese , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
13.
Med Sci Monit ; 26: e919241, 2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31955177

RESUMO

BACKGROUND This study aimed to investigate the expression of microRNA-639 (miR-639) in tumor tissue from patients with hepatocellular carcinoma (HCC) and its effects on patient outcome, to identify the targets for miR-639 using bioinformatics and luciferase reporter analysis, and the effects of miR-639 in human HCC cells in vitro to identify the molecular pathways involved. MATERIAL AND METHODS Expression levels of miR-639 were compared in tumor tissue and adjacent normal liver tissue from 50 patients with HCC, and Kaplan-Meier curves identified the association with overall survival (OS). miR-639 expression was measured in HCC cells cultured in vitro using quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and Western blot. HCC cells were studied using the MTT assay, the colony formation assay, and the transwell assay. Bioinformatics and luciferase reporter analysis identified the role of the histone acetyltransferase gene, KAT7, in HCC. RESULTS The expression of miR-639 was significantly reduced in HCC tissues compared with normal adjacent liver tissues, and inhibited cell proliferation and epithelial-mesenchymal transition (EMT) of HCC cells. Bioinformatics and luciferase reporter analysis showed that miR-639 directly targeted KAT7 and inhibit its expression. KAT7 expression promoted cell proliferation, and migration of human HCC cells in vitro, and miR-639 inhibited cell proliferation and EMT by down-regulating the KAT7/Wnt/ß-catenin signaling pathway. CONCLUSIONS miR-639 was down-regulated in HCC tumor tissue, and inhibited proliferation and migration of HCC cells by the down-regulation of KAT7/Wnt/ß-catenin signaling and was associated with reduced OS. These findings supported the potential role of miR-639 as a tumor suppressor.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Movimento Celular/genética , Regulação para Baixo/genética , Histona Acetiltransferases/metabolismo , Neoplasias Hepáticas/genética , MicroRNAs/genética , Via de Sinalização Wnt/genética , Regiões 3' não Traduzidas/genética , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Análise de Sobrevida
14.
Int Microbiol ; 23(1): 121-126, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31915950

RESUMO

In the present manuscript, we describe the mechanisms involved in the yeast-to-hypha dimorphic transition of the plant pathogenic Basidiomycota fungus Ustilago maydis. During its life cycle, U. maydis presents two stages: one in the form of haploid saprophytic yeasts that divide by budding and the other that is the product of the mating of sexually compatible yeast cells (sporidia), in the form of mycelial dikaryons that invade the plant host. The occurrence of the involved dimorphic transition is controlled by the two mating loci a and b. In addition, the dimorphic event can be obtained in vitro by different stimuli: change in the pH of the growth medium, use of different carbon sources, and by nitrogen depletion. The presence of other factors and mechanisms may affect this phenomenon; among these, we may cite the PKA and MAPK signal transduction pathways, polyamines, and factors that affect the structure of the nucleosomes. Some of these factors and conditions may affect all these dimorphic events, or they may be specific for only one or more but not all the processes involved. The conclusion reached by these experiments is that U. maydis has constituted a useful model for the analysis of the mechanisms involved in cell differentiation of fungi in general.


Assuntos
Transdução de Sinais , Ustilago/citologia , Ustilago/fisiologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Metilação de DNA , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Histidina Quinase/metabolismo , Histona Acetiltransferases/metabolismo , Homeostase , Concentração de Íons de Hidrogênio , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Poliaminas/metabolismo
15.
Nature ; 577(7792): 717-720, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31969703

RESUMO

Gene transcription by RNA polymerase II is regulated by activator proteins that recruit the coactivator complexes SAGA (Spt-Ada-Gcn5-acetyltransferase)1,2 and transcription factor IID (TFIID)2-4. SAGA is required for all regulated transcription5 and is conserved among eukaryotes6. SAGA contains four modules7-9: the activator-binding Tra1 module, the core module, the histone acetyltransferase (HAT) module and the histone deubiquitination (DUB) module. Previous studies provided partial structures10-14, but the structure of the central core module is unknown. Here we present the cryo-electron microscopy structure of SAGA from the yeast Saccharomyces cerevisiae and resolve the core module at 3.3 Å resolution. The core module consists of subunits Taf5, Sgf73 and Spt20, and a histone octamer-like fold. The octamer-like fold comprises the heterodimers Taf6-Taf9, Taf10-Spt7 and Taf12-Ada1, and two histone-fold domains in Spt3. Spt3 and the adjacent subunit Spt8 interact with the TATA box-binding protein (TBP)2,7,15-17. The octamer-like fold and its TBP-interacting region are similar in TFIID, whereas Taf5 and the Taf6 HEAT domain adopt distinct conformations. Taf12 and Spt20 form flexible connections to the Tra1 module, whereas Sgf73 tethers the DUB module. Binding of a nucleosome to SAGA displaces the HAT and DUB modules from the core-module surface, allowing the DUB module to bind one face of an ubiquitinated nucleosome.


Assuntos
Microscopia Crioeletrônica , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/ultraestrutura , Saccharomyces cerevisiae , Transativadores/química , Transativadores/ultraestrutura , Transcrição Genética , Regulação Fúngica da Expressão Gênica , Histona Acetiltransferases/química , Histona Acetiltransferases/metabolismo , Histona Acetiltransferases/ultraestrutura , Histonas/metabolismo , Modelos Moleculares , Nucleossomos/química , Nucleossomos/metabolismo , Nucleossomos/ultraestrutura , Ligação Proteica , Domínios Proteicos , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/ultraestrutura , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteína de Ligação a TATA-Box/química , Proteína de Ligação a TATA-Box/metabolismo , Transativadores/metabolismo , Fator de Transcrição TFIID/metabolismo , Ubiquitinação
16.
Jpn J Clin Oncol ; 50(3): 241-253, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-31990345

RESUMO

BACKGROUND: This study aims to analyse the expression of human MOF in endometrial carcinoma cells and its relationship with estrogen and estrogen receptor and to investigate the effect of estrogen-human MOF on the malignant biological behaviours of endometrial carcinoma cells. METHODS: The expression of human MOF was detected in different endometrial tissues by immunohistochemistry. The effects of human MOF, human MOF combined with estrogen stimulation and estrogen plus anti-human MOF antibody blocking on the proliferation of endometrial carcinoma cells were evaluated by western blotting, real-time polymerase chain reaction, cell proliferation assay and cell cycle distribution. Bioinformatics was used to identify the correlations of human MOF and estrogen and involved pathways. RESULTS: The expression levels of human MOF in endometrial carcinoma tissues were significantly higher than that in atypical hyperplasia and normal endometrial tissues. High expression of human MOF was associated with late-stage cancer, lymph node metastasis and short survival time, and it was also an independent prognostic risk factor for endometrial carcinoma. After human MOF knockdown, the proliferation, migration and invasive capacity of Ishikawa cells decreased and cell apoptosis increased. After stimulation with estrogen, the PI3K/Akt and Ras-Raf-MEK-ERK signalling pathways were activated, and the expression of the human MOF protein was increased. human MOF (KAT8) expression showed a positive correlation with ESR1 expression, and KAT8-associated genes were enriched in the cell cycle pathways and splicing pathways. CONCLUSION: Human MOF was highly expressed in endometrial carcinoma and associated with proliferation. Estrogen/estrogen receptor enhanced human MOF expression; promoted the proliferation, migration and invasion of Ishikawa cells; and inhibited cell apoptosis by activating the PI3K/Akt and Ras-Raf-MEK-ERK signalling pathways.


Assuntos
Neoplasias do Endométrio/metabolismo , Estrogênios/metabolismo , Histona Acetiltransferases/metabolismo , Receptores Estrogênicos/metabolismo , Adulto , Idoso , Apoptose , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Endométrio/metabolismo , Feminino , Histona Acetiltransferases/genética , Humanos , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Quinases/metabolismo , Transdução de Sinais , Adulto Jovem
17.
Nature ; 577(7792): 711-716, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31969704

RESUMO

SAGA (Spt-Ada-Gcn5-acetyltransferase) is a 19-subunit complex that stimulates transcription via two chromatin-modifying enzymatic modules and by delivering the TATA box binding protein (TBP) to nucleate the pre-initiation complex on DNA, a pivotal event in the expression of protein-encoding genes1. Here we present the structure of yeast SAGA with bound TBP. The core of the complex is resolved at 3.5 Å resolution (0.143 Fourier shell correlation). The structure reveals the intricate network of interactions that coordinate the different functional domains of SAGA and resolves an octamer of histone-fold domains at the core of SAGA. This deformed octamer deviates considerably from the symmetrical analogue in the nucleosome and is precisely tuned to establish a peripheral site for TBP, where steric hindrance represses binding of spurious DNA. Complementary biochemical analysis points to a mechanism for TBP delivery and release from SAGA that requires transcription factor IIA and whose efficiency correlates with the affinity of DNA to TBP. We provide the foundations for understanding the specific delivery of TBP to gene promoters and the multiple roles of SAGA in regulating gene expression.


Assuntos
Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Pichia , Regiões Promotoras Genéticas/genética , Proteína de Ligação a TATA-Box/metabolismo , Transativadores/química , Transativadores/metabolismo , Sítios de Ligação , DNA Fúngico/química , DNA Fúngico/metabolismo , Regulação Fúngica da Expressão Gênica , Histona Acetiltransferases/química , Histona Acetiltransferases/metabolismo , Histonas/química , Histonas/metabolismo , Modelos Moleculares , Pichia/química , Pichia/genética , Ligação Proteica , Conformação Proteica , Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores Associados à Proteína de Ligação a TATA/química , Fatores Associados à Proteína de Ligação a TATA/metabolismo , Proteína de Ligação a TATA-Box/química , Fator de Transcrição TFIIA/química , Fator de Transcrição TFIIA/metabolismo , Fator de Transcrição TFIID/química , Fator de Transcrição TFIID/metabolismo
18.
Nature ; 577(7789): 266-270, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31827282

RESUMO

Acute myeloid leukaemia (AML) is a heterogeneous disease characterized by transcriptional dysregulation that results in a block in differentiation and increased malignant self-renewal. Various epigenetic therapies aimed at reversing these hallmarks of AML have progressed into clinical trials, but most show only modest efficacy owing to an inability to effectively eradicate leukaemia stem cells (LSCs)1. Here, to specifically identify novel dependencies in LSCs, we screened a bespoke library of small hairpin RNAs that target chromatin regulators in a unique ex vivo mouse model of LSCs. We identify the MYST acetyltransferase HBO1 (also known as KAT7 or MYST2) and several known members of the HBO1 protein complex as critical regulators of LSC maintenance. Using CRISPR domain screening and quantitative mass spectrometry, we identified the histone acetyltransferase domain of HBO1 as being essential in the acetylation of histone H3 at K14. H3 acetylated at K14 (H3K14ac) facilitates the processivity of RNA polymerase II to maintain the high expression of key genes (including Hoxa9 and Hoxa10) that help to sustain the functional properties of LSCs. To leverage this dependency therapeutically, we developed a highly potent small-molecule inhibitor of HBO1 and demonstrate its mode of activity as a competitive analogue of acetyl-CoA. Inhibition of HBO1 phenocopied our genetic data and showed efficacy in a broad range of human cell lines and primary AML cells from patients. These biological, structural and chemical insights into a therapeutic target in AML will enable the clinical translation of these findings.


Assuntos
Histona Acetiltransferases/metabolismo , Leucemia Mieloide Aguda/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Linhagem Celular Tumoral , Histona Acetiltransferases/química , Histona Acetiltransferases/genética , Humanos , Leucemia Mieloide Aguda/genética , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Estrutura Terciária de Proteína
19.
Cell Mol Life Sci ; 77(4): 637-649, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31535175

RESUMO

HBO1 complexes are major acetyltransferase responsible for histone H4 acetylation in vivo, which belongs to the MYST family. As the core catalytic subunit, HBO1 consists of an N-terminal domain and a C-terminal MYST domain that are in charge of acetyl-CoA binding and acetylation reaction. HBO1 complexes are multimeric and normally consist of two native subunits MEAF6, ING4 or ING5 and two kinds of cofactors as chromatin reader: Jade-1/2/3 and BRPF1/2/3. The choices of subunits to form the HBO1 complexes provide a regulatory switch to potentiate its activity between histone H4 and H3 tails. Thus, HBO1 complexes present multiple functions in histone acetylation, gene transcription, DNA replication, protein ubiquitination, and immune regulation, etc. HBO1 is a co-activator for CDT1 to facilitate chromatin loading of MCM complexes and promotes DNA replication licensing. This process is regulated by mitotic kinases such as CDK1 and PLK1 by phosphorylating HBO1 and modulating its acetyltransferase activity, therefore, connecting histone acetylation to regulations of cell cycle and DNA replication. In addition, both gene amplification and protein overexpression of HBO1 confirmed its oncogenic role in cancers. In this paper, we review the recent advances and discuss our understanding of the multiple functions, activity regulation, and disease relationship of HBO1.


Assuntos
Histona Acetiltransferases/metabolismo , Neoplasias/metabolismo , Acetilação , Animais , Carcinogênese/genética , Carcinogênese/metabolismo , Replicação do DNA , Regulação Neoplásica da Expressão Gênica , Histona Acetiltransferases/química , Histona Acetiltransferases/genética , Histonas/genética , Histonas/metabolismo , Humanos , Modelos Moleculares , Neoplasias/genética , Ativação Transcricional
20.
Biochimie ; 168: 268-276, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31786230

RESUMO

Histone acetyltransferase (Hpa2) is an unusual acetyltransferase, with a wide range of substrates; including histones, polyamines and aminoglycosides antibiotic. Hpa2 belongs to GNAT superfamily and GNATs are well known for the formation of homo-oligomers. However, the reason behind their oligomerization remained unexplored. Here, oligomeric states of Hpa2 were explored, to understand the functional significance of oligomerization. Biochemical analysis suggests that Hpa2 exists as dimer in solution and self-assembles into tetramer in the spermine, spermidine and kanamycin bound form. Stability analysis with denaturants concludes that homo-oligomerization of Hpa2 relies on bound substrate and not on experimental conditions. Homo-oligomerization in Hpa2 depicts direct correlation with its polyamine acetylating capacity. This correlation and in silico model structures suggest that oligomerization of Hpa2 is associated with the hastening of acetylation process. Interestingly, polyamine acetylation down regulates biofilms formation in E. coli BL21/Hpa2-transformants cells. Therefore, we propose that Hpa2 manipulates survival strategies of the bacterium via polyamines and antibiotics acetylation.


Assuntos
Acinetobacter baumannii/enzimologia , Histona Acetiltransferases/química , Histona Acetiltransferases/metabolismo , Poliaminas/metabolismo , Acetilação , Biofilmes , Farmacorresistência Bacteriana Múltipla , Escherichia coli/metabolismo , Escherichia coli/fisiologia , Canamicina/metabolismo , Multimerização Proteica , Espermidina/metabolismo , Espermina/metabolismo
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