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1.
Gene ; 851: 146928, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36191822

RESUMO

Bone formation is controlled by histone modifying enzymes that regulate post-translational modifications on nucleosomal histone proteins and control accessibility of transcription factors to gene promoters required for osteogenesis. Enhancer of Zeste homolog 2 (EZH2/Ezh2), a histone H3 lysine 27 (H3K27) methyl transferase, is a suppressor of osteoblast differentiation. Ezh2 is regulated by SET and MYND domain-containing protein 2 (SMYD2/Smyd2), a lysine methyltransferase that modifies both histone and non-histone proteins. Here, we examined whether Smyd2 modulates Ezh2 suppression of osteoblast differentiation. Musculoskeletal RNA-seq data show that SMYD2/Smyd2 is the most highly expressed SMYD/Smyd member in human bone tissues and mouse osteoblasts. Smyd2 loss of function analysis in mouse MC3T3 osteoblasts using siRNA depletion enhances proliferation and calcium deposition. Loss of Smyd2 protein does not affect alkaline phosphatase activity nor does it result in a unified expression response for standard osteoblast-related mRNA markers (e.g., Bglap, Ibsp, Spp1, Sp7), indicating that Smyd2 does not directly control osteoblast differentiation. Smyd2 protein depletion enhances levels of the osteo-suppressive Ezh2 protein and H3K27 trimethylation (H3K27me3), as expected from increased cell proliferation, while elevating the osteo-inductive Runx2 protein. Combined siRNA depletion of both Smyd2 and Ezh2 protein is more effective in promoting calcium deposition when compared to loss of either protein. Collectively, our results indicate that Smyd2 inhibits proliferation and indirectly the subsequent mineral deposition by osteoblasts. Mechanistically, Smyd2 represents a functional epigenetic regulator that operates in parallel to the suppressive effects of Ezh2 and H3K27 trimethylation on osteoblast differentiation.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste , Lisina , Camundongos , Animais , Humanos , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Lisina/metabolismo , Metiltransferases/metabolismo , RNA Interferente Pequeno/metabolismo , Cálcio/metabolismo , Domínios MYND , Osteoblastos/metabolismo , Histonas/metabolismo , Proliferação de Células/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo
2.
Cell Rep ; 41(8): 111703, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36417856

RESUMO

Macrophages are critical immune cells in inflammatory diseases, and their differentiation and function are tightly regulated by histone modifications. H3K79 methylation is a histone modification associated with active gene expression, and DOT1L is the only histone methyltransferase for H3K79. Here we determine the role of DOT1L in macrophages by applying a selective DOT1L inhibitor in mouse and human macrophages and using myeloid-specific Dot1l-deficient mice. We found that DOT1L directly regulates macrophage function by controlling lipid biosynthesis gene programs including central lipid regulators like sterol regulatory element-binding proteins SREBP1 and SREBP2. DOT1L inhibition also leads to macrophage hyperactivation, which is associated with disrupted SREBP pathways. In vivo, myeloid Dot1l deficiency reduces atherosclerotic plaque stability and increases the activation of inflammatory plaque macrophages. Our data show that DOT1L is a crucial regulator of macrophage inflammatory responses and lipid regulatory pathways and suggest a high relevance of H3K79 methylation in inflammatory disease.


Assuntos
Histona-Lisina N-Metiltransferase , Placa Aterosclerótica , Humanos , Camundongos , Animais , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Macrófagos/metabolismo , Lipídeos
3.
Epigenetics Chromatin ; 15(1): 36, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36411491

RESUMO

Epigenetic modifications to histone proteins serve an important role in regulating permissive and repressive chromatin states, but despite the identification of many histone PTMs and their perceived role, the epigenetic writers responsible for generating these chromatin signatures are not fully characterized. Here, we report that the canonical histone H3K9 methyltransferases EHMT1/GLP and EHMT2/G9a are capable of catalyzing methylation of histone H3 lysine 23 (H3K23). Our data show that while both enzymes can mono- and di-methylate H3K23, only EHMT1/GLP can tri-methylate H3K23. We also show that pharmacologic inhibition or genetic ablation of EHMT1/GLP and/or EHMT2/G9a leads to decreased H3K23 methylation in mammalian cells. Taken together, this work identifies H3K23 as a new direct methylation target of EHMT1/GLP and EHMT2/G9a, and highlights the differential activity of these enzymes on H3K23 as a substrate.


Assuntos
Histona-Lisina N-Metiltransferase , Histonas , Animais , Metilação , Histonas/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Processamento de Proteína Pós-Traducional , Histona Metiltransferases/genética , Cromatina , Mamíferos/genética
4.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(10): 1303-1314, 2022 Oct 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36411681

RESUMO

OBJECTIVES: Our previous study has verified that high level of SET and MYND domain-containing protein 2 (SMYD2) plays an important role in acquiring aggressive ability for liver cancer cells in hepatocellular carcinoma. MiR-200b as a tumor suppressor gene involves in a variety of cancers. This study aims to investigate the correlation between miR-200b and SMYD2 in hepatocellular carcinoma and the underlying mechanism. METHODS: Firstly, the levels of SMYD2 and miR-200b in hepatocellular carcinoma tissues and matched adjacent non-tumor liver tissues were tested with real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. Secondly, we evaluated the interaction between miR-200b and SMYD2 using dual-luciferase reporter assay. Thirdly, we elucidated the effect of miR-200b on SMYD2 and its downstream targets p53/CyclinE1. Finally, we silenced SMYD2 in hepatocellular carcinoma cell lines to investigate its effect on tumor proliferation and cell cycle progression, and further confirmed the correlation among SMYD2 and p53/CyclinE1. RESULTS: Compared with the matched adjacent non-tumor liver tissues, miR-200b was obviously decreased, and SMYD2 was significantly increased in hepatocellular carcinoma (both P<0.05). Spearman's rank correlation revealed that miR-200b expression was negatively correlated with SMYD2 (P<0.01). Computer algorithm and dual-luciferase reporter assay revealed that miR-200b directly targeted and suppressed SMYD2 in HEK 293T cells. The down-regulated miR-200b expression promoted hepatoma cell proliferation (P<0.05) and increased SMYD2 expression(P<0.01), while the up-regulated expression of miR-200b had an opposite effect. The knockdown of SMYD2 suppressed the proliferation of MHCC-97L cells (P<0.01), down-regulated CyclinE1, and up-regulated p53 expression (both P<0.05). CONCLUSIONS: MiR-200b is involved in hepatocellular carcinoma progression via targeting SMYD2 and regulating SMYD2/p53/CyclinE1 signaling pathway and may be used as a potential target for hepatocellular carcinoma treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais , Neoplasias Hepáticas/patologia , Proliferação de Células/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo
5.
Genes (Basel) ; 13(11)2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36360250

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is the sixth most prevalent non-skin cancer in the world. While immunotherapy has revolutionized the standard of care treatment in patients with recurrent/metastatic HNSCC, more than 70% of patients do not respond to this treatment, making the identification of novel therapeutic targets urgent. Recently, research endeavors have focused on how epigenetic modifications may affect tumor initiation and progression of HNSCC. The nuclear receptor binding SET domain (NSD) family of protein methyltransferases NSD1-NSD3 is of particular interest for HNSCC, with NSD1 and NSD3 being amongst the most commonly mutated or amplified genes respectively in HNSCC. Preclinical studies have identified both oncogenic and tumor-suppressing properties across NSD1, NSD2, and NSD3 within the context of HNSCC. The purpose of this review is to provide a better understanding of the contribution of the NSD family of protein methyltransferases to the pathogenesis of HNSCC, underscoring their promise as novel therapeutic targets in this devastating disease.


Assuntos
Neoplasias de Cabeça e Pescoço , Histona-Lisina N-Metiltransferase , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Recidiva Local de Neoplasia/genética , Neoplasias de Cabeça e Pescoço/genética , Epigênese Genética
6.
Sci Rep ; 12(1): 19251, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357422

RESUMO

Posttranslational modifications (PTMs) on histone tails regulate eukaryotic gene expression by impacting the chromatin structure and by modulating interactions with other cellular proteins. One such PTM has been identified as serine and threonine glycosylation, the introduction of the ß-N-acetylglucosamine (GlcNAc) moiety on histone H3 tail at position Ser10 and Thr32. The addition of the ß-O-GlcNAc moiety on serine or threonine residues is facilitated by the O-GlcNAc transferase (OGT), and can be removed by the action of O-GlcNAcase (OGA). Conflicting reports on histone tail GlcNAc modification in vivo prompted us to investigate whether synthetic histone H3 tail peptides in conjunction with other PTMs are substrates for OGT and OGA in vitro. Our enzymatic assays with recombinantly expressed human OGT revealed that the unmodified and PTM-modified histone H3 tails are not substrates for OGT at both sites, Ser10 and Thr32. In addition, full length histone H3 was not a substrate for OGT. Conversely, our work demonstrates that synthetic peptides containing the GlcNAc functionality at Ser10 are substrates for recombinantly expressed human OGA, yielding deglycosylated histone H3 peptides. We also show that the catalytic domains of human histone lysine methyltransferases G9a, GLP and SETD7 and histone lysine acetyltransferases PCAF and GCN5 do somewhat tolerate glycosylated H3Ser10 close to lysine residues that undergo methylation and acetylation reactions, respectively. Overall, this work indicates that GlcNAcylation of histone H3 tail peptide in the presence of OGT does not occur in vitro.


Assuntos
Histonas , Lisina , Humanos , Histonas/metabolismo , Glicosilação , Lisina/metabolismo , N-Acetilglucosaminiltransferases/genética , Acetilglucosamina/metabolismo , Processamento de Proteína Pós-Traducional , Treonina/metabolismo , Peptídeos/metabolismo , Serina/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo
7.
Nat Commun ; 13(1): 6907, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376321

RESUMO

Transcription replication collisions (TRCs) constitute a major intrinsic source of genome instability but conclusive evidence for a causal role of TRCs in tumor initiation is missing. We discover that lack of the H4K20-dimethyltransferase KMT5B (also known as SUV4-20H1) in muscle stem cells de-represses S-phase transcription by increasing H4K20me1 levels, which induces TRCs and aberrant R-loops in oncogenic genes. The resulting replication stress and aberrant mitosis activate ATR-RPA32-P53 signaling, promoting cellular senescence, which turns into rapid rhabdomyosarcoma formation when p53 is absent. Inhibition of S-phase transcription ameliorates TRCs and formation of R-loops in Kmt5b-deficient MuSCs, validating the crucial role of H4K20me1-dependent, tightly controlled S-phase transcription for preventing collision errors. Low KMT5B expression is prevalent in human sarcomas and associated with tumor recurrence, suggesting a common function of KMT5B in sarcoma formation. The study uncovers decisive functions of KMT5B for maintaining genome stability by repressing S-phase transcription via control of H4K20me1 levels.


Assuntos
Células-Tronco Adultas , Histona-Lisina N-Metiltransferase , Humanos , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Recidiva Local de Neoplasia , Fase S/genética , Instabilidade Genômica , Transformação Celular Neoplásica/genética , Células-Tronco Adultas/metabolismo , Replicação do DNA/genética
8.
Nat Commun ; 13(1): 6578, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36323669

RESUMO

Enhancer deregulation is a well-established pro-tumorigenic mechanism but whether it plays a regulatory role in tumor immunity is largely unknown. Here, we demonstrate that tumor cell ablation of mixed-lineage leukemia 3 and 4 (MLL3 and MLL4, also known as KMT2C and KMT2D, respectively), two enhancer-associated histone H3 lysine 4 (H3K4) mono-methyltransferases, increases tumor immunogenicity and promotes anti-tumor T cell response. Mechanistically, MLL4 ablation attenuates the expression of RNA-induced silencing complex (RISC) and DNA methyltransferases through decommissioning enhancers/super-enhancers, which consequently lead to transcriptional reactivation of the double-stranded RNA (dsRNA)-interferon response and gasdermin D (GSDMD)-mediated pyroptosis, respectively. More importantly, we reveal that both the dsRNA-interferon signaling and GSDMD-mediated pyroptosis are of critical importance to the increased anti-tumor immunity and improved immunotherapeutic efficacy in MLL4-ablated tumors. Thus, our findings establish tumor cell enhancers as an additional layer of immune evasion mechanisms and suggest the potential of targeting enhancers or their upstream and/or downstream molecular pathways to overcome immunotherapeutic resistance in cancer patients.


Assuntos
Histona-Lisina N-Metiltransferase , Neoplasias , Humanos , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Elementos Facilitadores Genéticos , Histonas/metabolismo , RNA de Cadeia Dupla , Piroptose , Neoplasias/genética , Neoplasias/terapia , Neoplasias/metabolismo , Interferons/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
9.
Cell Death Dis ; 13(11): 953, 2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36371383

RESUMO

Macroautophagy/autophagy is an evolutionarily conserved and tightly regulated catabolic process involved in the maintenance of cellular homeostasis whose dysregulation is implicated in several pathological processes. Autophagy begins with the formation of phagophores that engulf cytoplasmic cargo and mature into double-membrane autophagosomes; the latter fuse with lysosomes/vacuoles for cargo degradation and recycling. Here, we report that yeast Set2, a histone lysine methyltransferase, and its mammalian homolog, SETD2, both act as positive transcriptional regulators of autophagy. However, whereas Set2 regulates the expression of several autophagy-related (Atg) genes upon nitrogen starvation, SETD2 effects in mammals were found to be more restricted. In fact, SETD2 appears to primarily regulate the differential expression of protein isoforms encoded by the ATG14 gene. SETD2 promotes the expression of a long ATG14 isoform, ATG14L, that contains an N-terminal cysteine repeats domain, essential for the efficient fusion of the autophagosome with the lysosome, that is absent in the short ATG14 isoform, ATG14S. Accordingly, SETD2 loss of function decreases autophagic flux, as well as the turnover of aggregation-prone proteins such as mutant HTT (huntingtin) leading to increased cellular toxicity. Hence, our findings bring evidence to the emerging concept that the production of autophagy-related protein isoforms can differentially affect core autophagy machinery bringing an additional level of complexity to the regulation of this biological process in more complex organisms.


Assuntos
Autofagossomos , Macroautofagia , Animais , Autofagossomos/metabolismo , Lisossomos/metabolismo , Autofagia/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Mamíferos
10.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36232375

RESUMO

Alterations of the epigenetic machinery are critically involved in cancer development and maintenance; therefore, the proteins in charge of the generation of epigenetic modifications are being actively studied as potential targets for anticancer therapies. A very important and widespread epigenetic mark is the dimethylation of Histone 3 in Lysine 36 (H3K36me2). Until recently, it was considered as merely an intermediate towards the generation of the trimethylated form, but recent data support a more specific role in many aspects of genome regulation. H3K36 dimethylation is mainly carried out by proteins of the Nuclear SET Domain (NSD) family, among which NSD2 is one of the most relevant members with a key role in normal hematopoietic development. Consequently, NSD2 is frequently altered in several types of tumors-especially in hematological malignancies. Herein, we discuss the role of NSD2 in these pathological processes, and we review the most recent findings in the development of new compounds aimed against the oncogenic forms of this novel anticancer candidate.


Assuntos
Doenças Hematológicas , Neoplasias , Epigênese Genética , Doenças Hematológicas/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Humanos , Lisina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas Repressoras/genética
11.
J Cell Mol Med ; 26(22): 5624-5633, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36300880

RESUMO

Curcumin is a known epigenetic modifier that demonstrated antitumor effect in different types of cancer. The poor solubility and metabolic stability are major drawbacks that limit its development as an antitumor agent. Dimethoxycurcumin (DMC) is a more soluble and stable curcumin analog. In this study, we compared the effect of both drugs on a variety of histone posttranslational modifications and on the activity of histone lysine methyltransferase (HKMTs) and demethylase (HKDMTs) enzymes that target the H3K4, H3K9 and H3K27 epigenetic marks. Mass spectrometry was used to quantitate the changes in 95 histone posttranslational modifications induced by curcumin or DMC. The effect of both drugs on the enzymatic activity of HKMTs and HKDMs was measured using an antibody-based assay. Mass spectrometry analysis showed that curcumin and DMC modulated several histone modifications. Histone changes were not limited to lysine methylation and acetylation but included arginine and glutamine methylation. Only few histone modifications were similarly changed by both drugs. On the contrary, the effect of both drugs on the activity of HKMTs and HKDMs was very similar. Curcumin and DMC inhibited the HKMTs enzymes that target the H3K4, H3K9 and H3K27 marks and increased the activity of the HKDMs enzymes LSD1, JARID and JMJD2. In conclusion, we identified novel enzymatic targets for both curcumin and DMC that support their use and development as epigenetic modifiers in cancer treatment. The multiple targets modulated by both drugs could provide a therapeutic advantage by overcoming drug resistance development.


Assuntos
Curcumina , Leucemia , Humanos , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Curcumina/farmacologia , Leucemia/tratamento farmacológico
12.
Biomaterials ; 290: 121819, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36209579

RESUMO

The faithful engineering of complex human tissues such as the bone/soft tissue/mineralized tissue interface in periodontal tissues requires innovative molecular cues in conjunction with tailored scaffolds. To address the loss of periodontal bone and connective tissues following periodontal disease, we have generated a polydopamine and collagen coated electrospun PLGA-PCL (PP) scaffold enriched with the small molecule mediator PFI-2 (PP-PFI-pDA-COL-PFI). In vitro 3D studies using PDL progenitors revealed that the PP-PFI-pDA-COL-PFI scaffold substantially enhanced Alizarin Red staining, increased Ca/P ratios 4-fold, and stimulated cell proliferation more than 12-fold compared to PP-controls, suggestive of its potential for mineralized tissue engineering. When applied in our experimental periodontitis model, the PP-PFI-pDA-COL-PFI scaffold resulted in a substantial 34% reduction in alveolar bone defect height, a 25% root-length gain in periodontal attachment, and the formation of highly ordered regenerated acellular cementum twice as thick as in controls. Explaining the mechanism of PFI-2 mineralized tissue regeneration in periodontal tissues, PFI-2 inhibited SETD7-mediated ß-Catenin protein methylation and increased ß-Catenin nuclear localization. Together, dual-level PFI-2 incorporation into a degradable, dopamine/collagen coated PLGA/PCL scaffold backbone resulted in the regeneration of the tripartite periodontal complex with unprecedented fidelity, including periodontal attachment and new formation of mineralized tissues in inflamed periodontal environments.


Assuntos
Ligamento Periodontal , Tecidos Suporte , Humanos , Isoquinolinas/metabolismo , Colágeno/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Histona-Lisina N-Metiltransferase/metabolismo
13.
Cell Death Dis ; 13(10): 890, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36270984

RESUMO

Adipogenesis is a complex cascade involved with the preadipocytes differentiation towards mature adipocytes, accelerating the onset of obesity. Histone methyltransferase SET and MYND domain-containing protein 2 (Smyd2), is involved in a variety of cellular biological functions but the epigenetic regulation of Smyd2 in adipogenesis and adipocyte differentiation remains unclear. Both Smyd2 siRNA and LLY-507, an inhibitor of Smyd2, were used to examine the effect of Smyd2 on adipogenesis and adipocyte differentiation in vitro. Smyd2 heterozygous knockout (Smyd2+/-) mice were also constructed to validate the relationship between Smyd2 and adipogenesis in vivo. We found that Smyd2 is abundant in white adipose tissue and closely correlated with adipocyte differentiation. Knockdown or inhibition of Smyd2 restrained adipocyte differentiation in vitro, which requires the phosphorylation of STAT3. In vivo functional validation, Smyd2+/- mice exert significant fat loss but not susceptible to HFD-induced obesity. Taken together, our findings revealed that Smyd2 is a novel regulator of adipocyte differentiation by regulating the phosphorylation of STAT3, which provides insights into the effects of epigenetic regulation in adipogenesis. Inhibition of Smyd2 might represent a viable strategy for anti-adipogenesis and maybe further alleviate obesity-related diseases in humans.


Assuntos
Epigênese Genética , Obesidade , Animais , Humanos , Camundongos , Células 3T3-L1 , Histona Metiltransferases/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Obesidade/genética , Obesidade/metabolismo , Fosforilação , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
14.
Int J Oral Sci ; 14(1): 44, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064768

RESUMO

Traumatic brain injury (TBI) contributes to the key causative elements of neurological deficits. However, no effective therapeutics have been developed yet. In our previous work, extracellular vesicles (EVs) secreted by stem cells from human exfoliated deciduous teeth (SHED) offered new insights as potential strategies for functional recovery of TBI. The current study aims to elucidate the mechanism of action, providing novel therapeutic targets for future clinical interventions. With the miRNA array performed and Real-time PCR validated, we revealed the crucial function of miR-330-5p transferred by SHED-derived EVs (SHED-EVs) in regulating microglia, the critical immune modulator in central nervous system. MiR-330-5p targeted Ehmt2 and mediated the transcription of CXCL14 to promote M2 microglia polarization and inhibit M1 polarization. Identified in our in vivo data, SHED-EVs and their effector miR-330-5p alleviated the secretion of inflammatory cytokines and resumed the motor functional recovery of TBI rats. In summary, by transferring miR-330-5p, SHED-EVs favored anti-inflammatory microglia polarization through Ehmt2 mediated CXCL14 transcription in treating traumatic brain injury.


Assuntos
Lesões Encefálicas Traumáticas , Quimiocinas CXC , Vesículas Extracelulares , Histona-Lisina N-Metiltransferase , MicroRNAs , Microglia , Animais , Lesões Encefálicas Traumáticas/genética , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/terapia , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Microglia/metabolismo , Ratos , Células-Tronco/metabolismo
15.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142254

RESUMO

MLL3, also known as KMT2C, is a lysine mono-methyltransferase in charge of the writing of an epigenetic mark on lysine 4 from histone 3. The catalytic site of MLL3 is composed of four tyrosines, namely, Y44, Y69, Y128, and Y130. Tyrosine residues are highly conserved among lysine methyltransferases' catalytic sites, although their complete function is still unclear. The exploration of how modifications on these residues from the enzymatic machinery impact the enzymatic activity of MLL3 could shed light transversally into the inner functioning of enzymes with similar characteristics. Through the use of QMMM calculations, we focus on the effect of the mutation of each tyrosine from the catalytic site on the enzymatic activity and the product specificity in the current study. While we found that the mutations of Y44 and Y128 by phenylalanine inactivated the enzyme, the mutation of Y128 by alanine reactivated the enzymatic activity of MLL3. Moreover, according to our models, the Y128A mutant was even found to be capable of di- and tri-methylate lysine 4 from histone 3, what would represent a gain of function mutation, and could be responsible for the development of diseases. Finally, we were able to establish the inactivation mechanism, which involved the use of Y130 as a water occlusion structure, whose conformation, once perturbed by its mutation or Y128 mutant, allows the access of water molecules that sequester the electron pair from lysine 4 avoiding its methylation process and, thus, increasing the barrier height.


Assuntos
Histona-Lisina N-Metiltransferase , Histonas , Alanina/genética , Sítios de Ligação , Epigênese Genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Metilação , Fenilalanina/metabolismo , Tirosina/metabolismo , Água/metabolismo
16.
Cell Death Dis ; 13(9): 763, 2022 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-36057625

RESUMO

Genetic abnormalities in histone methyltransferases (HMTs) frequently occur in diffuse large B-cell lymphoma (DLBCL) and are related to its progression. SET and MYND domain containing 3 (SMYD3) is an HMT that is upregulated in various tumors and promotes their malignancy. However, to the best of our knowledge, the function of SMYD3 in DLBCL has not been investigated thus far. In the present study, 22 HMT genes related to cancer development were first selected according to current literature, and it was found that high SMYD3 expression was significantly associated with poor progression-free survival in patients with DLBCL. SMYD3 protein levels were upregulated and positively associated with poor prognosis and poor responsiveness to chemotherapy in patients with DLBCL. Functional examinations demonstrated that SMYD3 increased cell proliferation and the flux of aerobic glycolysis in DLBCL cells in vitro and in vivo and decreased cell sensitivity to doxorubicin in vitro. Moreover, SMYD3 could directly bind to specific sequences of Pyruvate Kinase M2 (PKM2) and promote DLBCL cell proliferation and aerobic glycolysis via H3K4me3-mediated PKM2 transcription. Clinically, SMYD3 expression positively correlated with that of PKM2, and high SMYD3 was significantly associated with high maximum standardized uptake value (SUVmax) detected by [(18)F]-fluorodeoxyglucose ((18)F-FDG) PET/computed tomography (PET/CT) in DLBCL samples. Concomitant expression of SMYD3 and PKM2 positively correlated with poor progression-free and overall survival in patients with DLBCL and may serve as novel biomarkers in DLBCL.


Assuntos
Proteínas de Transporte/genética , Linfoma Difuso de Grandes Células B , Proteínas de Membrana/genética , Hormônios Tireóideos/genética , Fluordesoxiglucose F18 , Glicólise , Histona-Lisina N-Metiltransferase/metabolismo , Histonas , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Piruvato Quinase
17.
Int J Mol Sci ; 23(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36077559

RESUMO

The process of ubiquitination regulates the degradation, transport, interaction, and stabilization of substrate proteins, and is crucial for cell signal transduction and function. TNF receptor-associated factor 4, TRAF4, is a member of the TRAF family and is involved in the process of ubiquitination as an E3 ubiquitin protein ligase. Here, we found that TRAF4 expression correlates with glioma subtype and grade, and that TRAF4 is significantly overexpressed in glioblastoma and predicts poor prognosis. Knockdown of TRAF4 significantly inhibited the growth, proliferation, migration, and invasion of glioblastoma cells. Mechanistically, we found that TRAF4 only interacts with the Tudor domain of the AKT pathway activator SETDB1. TRAF4 mediates the atypical ubiquitination of SETDB1 to maintain its stability and function, thereby promoting the activation of the AKT pathway. Restoring SETDB1 expression in TRAF4 knockdown glioblastoma cells partially restored cell growth and proliferation. Collectively, our findings reveal a novel mechanism by which TRAF4 mediates AKT pathway activation, suggesting that TRAF4 may serve as a biomarker and promising therapeutic target for glioblastoma.


Assuntos
Glioblastoma , Fator 4 Associado a Receptor de TNF , Linhagem Celular Tumoral , Proliferação de Células/genética , Glioblastoma/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator 4 Associado a Receptor de TNF/genética , Fator 4 Associado a Receptor de TNF/metabolismo
18.
World J Gastroenterol ; 28(29): 3753-3766, 2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-36157542

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal neoplasms worldwide and represents the vast majority of pancreatic cancer cases. Understanding the molecular pathogenesis and the underlying mechanisms involved in the initiation, maintenance, and progression of PDAC is an urgent need, which may lead to the development of novel therapeutic strategies against this deadly cancer. Here, we review the role of SET and MYND domain-containing protein 2 (SMYD2) in initiating and maintaining PDAC development through methylating multiple tumor suppressors and oncogenic proteins. Given the broad substrate specificity of SMYD2 and its involvement in diverse oncogenic signaling pathways in many other cancers, the mechanistic extrapolation of SMYD2 from these cancers to PDAC may allow for developing new hypotheses about the mechanisms driving PDAC tumor growth and metastasis, supporting a proposition that targeting SMYD2 could be a powerful strategy for the prevention and treatment of PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/genética , Linhagem Celular Tumoral , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Domínios MYND , Neoplasias Pancreáticas/genética
19.
Genome Biol ; 23(1): 187, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36068616

RESUMO

BACKGROUND: The PRDM9-dependent histone methylation H3K4me3 and H3K36me3 function in assuring accurate homologous recombination at recombination hotspots in mammals. Beyond histone methylation, H3 lysine 9 acetylation (H3K9ac) is also greatly enriched at recombination hotspots. Previous work has indicated the potential cross-talk between H3K4me3 and H3K9ac at recombination hotspots, but it is still unknown what molecular mechanisms mediate the cross-talk between the two histone modifications at hotspots or how the cross-talk regulates homologous recombination in meiosis. RESULTS: Here, we find that the histone methylation reader ZCWPW1 is essential for maintaining H3K9ac by antagonizing HDAC proteins' deacetylation activity and further promotes chromatin openness at recombination hotspots thus preparing the way for homologous recombination during meiotic double-strand break repair. Interestingly, ectopic expression of the germ-cell-specific protein ZCWPW1 in human somatic cells enhances double-strand break repair via homologous recombination. CONCLUSIONS: Taken together, our findings provide new insights into how histone modifications and their associated regulatory proteins collectively regulate meiotic homologous recombination.


Assuntos
Cromatina , Código das Histonas , Animais , Quebras de DNA de Cadeia Dupla , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Recombinação Homóloga , Humanos , Mamíferos/metabolismo , Meiose
20.
Nat Struct Mol Biol ; 29(9): 898-909, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36064597

RESUMO

Heterochromatin assembly, involving histone H3 lysine-9 methylation (H3K9me), is nucleated at specific genomic sites but can self-propagate across extended domains and, indeed, generations. Self-propagation requires Clr4/Suv39h methyltransferase recruitment by pre-existing H3K9 tri-methylation (H3K9me3) to perpetuate H3K9me deposition and is dramatically affected by chromatin context. However, the mechanism priming self-propagation of heterochromatin remains undefined. We show that robust chromatin association of fission yeast class II histone deacetylase Clr3 is necessary and sufficient to support heterochromatin propagation in different chromosomal contexts. Efficient targeting of Clr3, which suppresses histone turnover and maintains H3K9me3, enables self-propagation of an ectopic heterochromatin domain via the Clr4/Suv39h read-write mechanism requiring methylated histones. The deacetylase activity of Clr3 is necessary and, when inactivated, heterochromatin propagation can be recapitulated by removing two major histone acetyltransferases. Our results show that histone deacetylation, a conserved heterochromatin feature, preserves H3K9me3 that transmits epigenetic memory for stable propagation of silenced chromatin domains through multiple generations.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Epigênese Genética , Heterocromatina/genética , Histona Acetiltransferases , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/genética , Histonas/metabolismo , Lisina/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo
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