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1.
Genes Dis ; 11(5): 101045, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38988321

RESUMEN

RNA N6-methyladenosine (m6A) methylation is the most abundant and conserved RNA modification in eukaryotes. It participates in the regulation of RNA metabolism and various pathophysiological processes. Non-coding RNAs (ncRNAs) are defined as small or long transcripts which do not encode proteins and display numerous biological regulatory functions. Similar to mRNAs, m6A deposition is observed in ncRNAs. Studying RNA m6A modifications on ncRNAs is of great importance specifically to deepen our understanding of their biological roles and clinical implications. In this review, we summarized the recent research findings regarding the mutual regulation between RNA m6A modification and ncRNAs (with a specific focus on microRNAs, long non-coding RNAs, and circular RNAs) and their functions. We also discussed the challenges of m6A-containing ncRNAs and RNA m6A as therapeutic targets in human diseases and their future perspective in translational roles.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38913865

RESUMEN

Hematopoietic homeostasis is maintained by hematopoietic stem cells (HSCs), and it is tightly controlled at multiple levels to sustain the self-renewal capacity and differentiation potential of HSCs. Dysregulation of self-renewal and differentiation of HSCs leads to the development of hematologic diseases, including acute myeloid leukemia (AML). Thus, understanding the underlying mechanisms of HSC maintenance and the development of hematologic malignancies is one of the fundamental scientific endeavors in stem cell biology. N  6-methyladenosine (m6A) is a common modification in mammalian messenger RNAs (mRNAs) and plays important roles in various biological processes. In this study, we performed a comparative analysis of the dynamics of the RNA m6A methylome of hematopoietic stem and progenitor cells (HSPCs) and leukemia-initiating cells (LICs) in AML. We found that RNA m6A modification regulates the transformation of long-term HSCs into short-term HSCs and determines the lineage commitment of HSCs. Interestingly, m6A modification leads to reprogramming that promotes cellular transformation during AML development, and LIC-specific m6A targets are recognized by different m6A readers. Moreover, the very long chain fatty acid transporter ATP-binding cassette subfamily D member 2 (ABCD2) is a key factor that promotes AML development, and deletion of ABCD2 damages clonogenic ability, inhibits proliferation, and promotes apoptosis of human leukemia cells. This study provides a comprehensive understanding of the role of m6A in regulating cell state transition in normal hematopoiesis and leukemogenesis, and identifies ABCD2 as a key factor in AML development.

3.
Acta Physiol (Oxf) ; 240(6): e14154, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38682314

RESUMEN

AIM: Type 2 diabetes mellitus (T2DM) is one of the most common diseases, and epigenetic modification N6-methyladenosine (m6A) is essential for transcriptional modulation involved in its development. However, the precise role and landscape of transcriptome-wide m6A alterations in molecular adaptations after physical exercise have yet to be fully elucidated. METHODS: Four-week-old male C57BL/6J mice received a high-fat diet (HFD) for 12 weeks to establish a diabetic state, and HFD mice were simultaneously subjected to physical exercise (HFD + EX). The hepatic RNA m6A methylome was examined, the conjoint MeRIP-seq and RNA-seq was performed, and the exercise-modulated genes were confirmed. RESULTS: Physical exercise significantly ameliorates liver metabolic disorder and triggers a dynamic change in hepatic RNA m6A. By analyzing the distribution of m6A in transcriptomes, an abundance of m6A throughout mRNA transcripts and a pattern of conserved m6A after physical exercise was identified. It is noteworthy that conjoint MeRIP-seq and RNA-seq data revealed that both differentially methylated genes and differentially expressed genes were enriched in all stages of the PI3K-Akt signaling pathway, in particular the upstream nodes of this pathway, which are considered a valuable therapeutic target for T2DM. Moreover, in vivo and in vitro analyses showed that exercise-mediated methyltransferase Rbm15 positively regulated the expression of two upstream genes (Itga3 and Fgf21) in an m6A-dependent manner. CONCLUSION: These findings highlight the pivotal role of the exercise-induced m6A epigenetic network and contribute insights into the intricate epigenetic mechanism underlying insulin signaling.


Asunto(s)
Diabetes Mellitus Tipo 2 , Condicionamiento Físico Animal , Transducción de Señal , Animales , Masculino , Ratones , Adenosina/análogos & derivados , Adenosina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Dieta Alta en Grasa , Epigénesis Genética , Hígado/metabolismo , Ratones Endogámicos C57BL , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Condicionamiento Físico Animal/fisiología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Transcriptoma
4.
Cell Rep ; 43(2): 113796, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38367240

RESUMEN

The acidic metabolic byproducts within the tumor microenvironment (TME) hinder T cell effector functions. However, their effects on T cell infiltration remain largely unexplored. Leveraging the comprehensive The Cancer Genome Atlas dataset, we pinpoint 16 genes that correlate with extracellular acidification and establish a metric known as the "tumor acidity (TuAci) score" for individual patients. We consistently observe a negative association between the TuAci score and T lymphocyte score (T score) across various human cancer types. Mechanistically, extracellular acidification significantly impedes T cell motility by suppressing podosome formation. This phenomenon can be attributed to the reduced expression of methyltransferase-like 3 (METTL3) and the modification of RNA N6-methyladenosine (m6A), resulting in a subsequent decrease in the expression of integrin ß1 (ITGB1). Importantly, enforced ITGB1 expression leads to enhanced T cell infiltration and improved antitumor activity. Our study suggests that modulating METTL3 activity or boosting ITGB1 expression could augment T cell infiltration within the acidic TME, thereby improving the efficacy of cell therapy.


Asunto(s)
Integrina beta1 , Neoplasias , Humanos , Tratamiento Basado en Trasplante de Células y Tejidos , Concentración de Iones de Hidrógeno , Integrina beta1/genética , Metiltransferasas/genética , Linfocitos T , Microambiente Tumoral
5.
Birth Defects Res ; 116(2): e2318, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38362594

RESUMEN

BACKGROUND: Arginase 1 (Arg1) encodes a key enzyme that catalyzes the metabolism of arginine to ornithine and urea. In our recent study, we found that knockdown of Arg1 in the lungs of fetal mice induces apoptosis of epithelial cells and dramatically delays initiation of labor. As the most abundant internal mRNA modification, N6 -methyladenosine (m6 A) has been found to play important roles in lung development and cellular differentiation. However, if the knockdown of Arg1 affects the RNA m6A modification in fetal lungs remains unknown. METHODS: In the current study, the RNA m6A levels and the expression of RNA m6A related enzymes were validated in 13.0 dpc fetal lungs that Arg1 was knocked down by adeno-associated virus carrying Arg1-shRNA, using western blot, immunofluorescence, and RT-qPCR. RESULTS: No statistical differences were found in the expression of methyltransferase, demethylases, and binding proteins in the fetal lungs between AAV-shArg1-injected mice and AAV-2/9-injected mice. Besides, there is no significant change of overall RNA m6A level in fetal lungs from AAV-shArg1-injected mice, compared with that from AAV-2/9-injected mice. CONCLUSIONS: These results indicate that arginase 1 does not affect RNA m6A methylation in mouse fetal lung, and the mechanisms other than RNA m6A modification underlying the effects of Arg1 knockdown on the fetal lung development and their interaction with labor initiation need to be further explored.


Asunto(s)
Arginasa , Metilación de ARN , Ratones , Animales , Arginasa/genética , Arginasa/metabolismo , Pulmón/metabolismo , Metiltransferasas/genética , Metiltransferasas/metabolismo , ARN/metabolismo
6.
Natl Sci Rev ; 10(12): nwad227, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38152479

RESUMEN

N6-methyladenosine (m6A) is a critical regulator in the fate of RNA, but whether and how m6A executes its functions in different tissues remains largely obscure. Here we report downregulation of a crucial m6A reader, YTHDF2, leading to tissue-specific programmed cell deaths (PCDs) upon fluorene-9-bisphenol (BHPF) exposure. Currently, Bisphenol A (BPA) substitutes are widely used in plastic manufacturing. Interrogating eight common BPA substitutes, we detected BHPF in 14% serum samples of pregnant participants. In a zebrafish model, BHPF caused tissue-specific PCDs triggering cardiac and vascular defects. Mechanistically, BHPF-mediated downregulation of YTHDF2 reduced YTHDF2-facilitated translation of m6A-gch1 for cardiomyocyte ferroptosis, and decreased YTHDF2-mediated m6A-sting1 decay for caudal vein plexus (CVP) apoptosis. The two distinct YTHDF2-mediated m6A regulations and context-dependent co-expression patterns of gch1/ythdf2 and tnfrsf1a/ythdf2 contributed to YTHDF2-mediated tissue-specific PCDs, uncovering a new layer of PCD regulation. Since BHPF/YTHDF2-medaited PCD defects were also observed in mammals, BHPF exposure represents a potential health threat.

7.
Discov Oncol ; 14(1): 233, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38110764

RESUMEN

BACKGROUND: Celastrol has been revealed to exhibit anticancer pharmacological activity, however, the molecular mechanisms of celastrol involved in pancreatic cancer remain to be further elucidated. The present study was to illustrate whether celastrol suppresses pancreatic cancer through modulating RNA m6A modification. METHODS: Effect of celastrol treatment on the malignant phenotypes of pancreatic cancer cells was evaluated by CCK-8 assay, EdU assay, colony formation assay, flow cytometry analysis and subcutaneous xenograft experiments. RNA sequencing (RNA-seq) analysis was carried out to analyze the genes differentially expressed in celastrol-treated pancreatic cancer cells. RT-qPCR, Western blotting and immunohistochemistry were employed to evaluate the expression of the indicated genes. RNA dot blot and quantification of total RNA m6A modification assays, MeRIP-qPCR assay, RIP-qPCR assay, RNA stability and protein stability assays were applied to evaluate the regulatory mechanism of celastrol treatment in pancreatic cancer cells. RESULTS: We demonstrated that celastrol suppressed cell proliferation and induced cell cycle arrest and apoptosis of pancreatic cancer cells in vitro, and decreased tumor growth in vivo. Specifically, Bcl-2, Claspin, METTL3 and YTHDF3 were identified as the potential targets of celastrol treatment in pancreatic cancer cells. Moreover, our results indicated that celastrol treatment downregulated METTL3 and decreased m6A levels of Claspin and Bcl-2 mRNA, leading to the degradation of Claspin and Bcl-2 mRNA in pancreatic cancer cells. Furthermore, we revealed that celastrol treatment downregulated Claspin and Bcl-2, at least in part, in an m6A-YTHDF3-mediated manner in pancreatic cancer cells. CONCLUSION: Our study highlighted a novel mechanism underlying celastrol-induced cellular proliferation inhibition and apoptosis in pancreatic cancer cells via m6A-YTHDF3-mediated downregulation of Claspin and Bcl-2.

8.
Toxicol Appl Pharmacol ; 481: 116764, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-37972769

RESUMEN

While arsenic or BaP alone exposure can cause lung cancer, studies showed that arsenic plus BaP co-exposure displays a significantly stronger lung tumorigenic effect. However, the underlying mechanism has not been well understood. Studies showed that RNA molecules are chemically modified. The most frequently occurring RNA modification in eukaryotic messenger RNAs is the N6-methyladenosine (m6A) methylation. This study aimed to determine whether arsenic plus BaP exposure alters RNA m6A methylation and its role in lung tumorigenic effect of arsenic plus BaP exposure. Human bronchial epithelial cells transformed by exposure to arsenic or BaP alone, and arsenic plus BaP and mouse xenograft tumorigenesis models were used in this study. It was found that arsenic plus BaP exposure-transformed cells have significantly higher levels of RNA m6A methylation than arsenic or BaP alone exposure-transformed human bronchial epithelial cells. Western blot analysis showed that arsenic plus BaP exposure greatly up-regulates the m6A writer methyltransferase like-3 (METTL3) expression levels in cultured cells and mouse lung tissues. METTL3 knockdown in cells transformed by arsenic plus BaP exposure drastically reduced their RNA m6A methylation levels. Functional studies revealed that METTL3 knockdown in cells transformed by arsenic plus BaP exposure greatly reduces their anchorage-dependent and -independent growth, cancer stem cell characters and tumorigenesis. The findings from this study suggest that arsenic plus BaP co-exposure causes epitranscriptomic dysregulation, which may contribute significantly to arsenic plus BaP co-exposure-caused synergistic lung tumorigenic effect.


Asunto(s)
Arsénico , Metiltransferasas , Células Madre Neoplásicas , ARN , Animales , Humanos , Ratones , Arsénico/toxicidad , Arsénico/metabolismo , Benzo(a)pireno/metabolismo , Benzo(a)pireno/toxicidad , Carcinogénesis/inducido químicamente , Carcinogénesis/genética , Metiltransferasas/genética , Metiltransferasas/metabolismo , Células Madre Neoplásicas/metabolismo , Regulación hacia Arriba
9.
Genes Dis ; 10(6): 2351-2365, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37554175

RESUMEN

Obesity has become a major health crisis in the past ∼50 years. The fat mass and obesity-associated (FTO) gene, identified by genome-wide association studies (GWAS), was first reported to be positively associated with obesity in humans. Mice with more copies of the FTO gene were observed to be obese, while loss of the gene in mice was found to protect from obesity. Later, FTO was found to encode an m6A RNA demethylase and has a profound effect on many biological and metabolic processes. In this review, we first summarize recent studies that demonstrate the critical roles and regulatory mechanisms of FTO in obesity and metabolic disease. Second, we discuss the ongoing debates concerning the association between FTO polymorphisms and obesity. Third, since several small molecule drugs and micronutrients have been found to regulate metabolic homeostasis through controlling the expression or activity of FTO, we highlight the broad potential of targeting FTO for obesity treatment. Improving our understanding of FTO and the underlying mechanisms may provide new approaches for treating obesity and metabolic diseases.

10.
Acta Pharm Sin B ; 13(6): 2795-2806, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37425036

RESUMEN

Metabolic engineering has been widely used for production of natural medicinal molecules. However, engineering high-yield platforms is hindered in large part by limited knowledge of complex regulatory machinery of metabolic network. N6-Methyladenosine (m6A) modification of RNA plays critical roles in regulation of gene expression. Herein, we identify 1470 putatively m6A peaks within 1151 genes from the haploid Saccharomyces cerevisiae strain. Among them, the transcript levels of 94 genes falling into the pathways which are frequently optimized for chemical production, are remarkably altered upon overexpression of IME4 (the yeast m6A methyltransferase). In particular, IME4 overexpression elevates the mRNA levels of the methylated genes in the glycolysis, acetyl-CoA synthesis and shikimate/aromatic amino acid synthesis modules. Furthermore, ACS1 and ADH2, two key genes responsible for acetyl-CoA synthesis, are induced by IME4 overexpression in a transcription factor-mediated manner. Finally, we show IME4 overexpression can significantly increase the titers of isoprenoids and aromatic compounds. Manipulation of m6A therefore adds a new layer of metabolic regulatory machinery and may be broadly used in bioproduction of various medicinal molecules of terpenoid and phenol classes.

11.
Cardiovasc Res ; 119(8): 1624-1640, 2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-36943786

RESUMEN

The haemostatic system is pivotal to maintaining vascular integrity. Multiple components involved in blood coagulation have central functions in inflammation and immunity. A derailed haemostasis is common in prevalent pathologies such as sepsis, cardiovascular disorders, and lately, COVID-19. Physiological mechanisms limit the deleterious consequences of a hyperactivated haemostatic system through adaptive changes in gene expression. While this is mainly regulated at the level of transcription, co- and posttranscriptional mechanisms are increasingly perceived as central hubs governing multiple facets of the haemostatic system. This layer of regulation modulates the biogenesis of haemostatic components, for example in situations of increased turnover and demand. However, they can also be 'hijacked' in disease processes, thereby perpetuating and even causally entertaining associated pathologies. This review summarizes examples and emerging concepts that illustrate the importance of posttranscriptional mechanisms in haemostatic control and crosstalk with the immune system. It also discusses how such regulatory principles can be used to usher in new therapeutic concepts to combat global medical threats such as sepsis or cardiovascular disorders.


Asunto(s)
COVID-19 , Enfermedades Cardiovasculares , Hemostáticos , MicroARNs , Humanos , COVID-19/genética , Hemostasis/genética , Regulación de la Expresión Génica , Coagulación Sanguínea/genética , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/terapia , MicroARNs/genética
12.
Acta Pharmaceutica Sinica B ; (6): 2795-2806, 2023.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-982854

RESUMEN

Metabolic engineering has been widely used for production of natural medicinal molecules. However, engineering high-yield platforms is hindered in large part by limited knowledge of complex regulatory machinery of metabolic network. N6-Methyladenosine (m6A) modification of RNA plays critical roles in regulation of gene expression. Herein, we identify 1470 putatively m6A peaks within 1151 genes from the haploid Saccharomyces cerevisiae strain. Among them, the transcript levels of 94 genes falling into the pathways which are frequently optimized for chemical production, are remarkably altered upon overexpression of IME4 (the yeast m6A methyltransferase). In particular, IME4 overexpression elevates the mRNA levels of the methylated genes in the glycolysis, acetyl-CoA synthesis and shikimate/aromatic amino acid synthesis modules. Furthermore, ACS1 and ADH2, two key genes responsible for acetyl-CoA synthesis, are induced by IME4 overexpression in a transcription factor-mediated manner. Finally, we show IME4 overexpression can significantly increase the titers of isoprenoids and aromatic compounds. Manipulation of m6A therefore adds a new layer of metabolic regulatory machinery and may be broadly used in bioproduction of various medicinal molecules of terpenoid and phenol classes.

13.
Blood Sci ; 4(3): 116-124, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36518594

RESUMEN

N6-Methyladenosine (m6A) is the most abundant modification in eukaryotic mRNA, and plays important biological functions via regulating RNA fate determination. Recent studies have shown that m6A modification plays a key role in hematologic malignancies, including acute myeloid leukemia. The current growth of epitranscriptomic research mainly benefits from technological progress in detecting RNA m6A modification in a transcriptome-wide manner. In this review, we first briefly summarize the latest advances in RNA m6A biology by focusing on writers, readers, and erasers of m6A modification, and describe the development of high-throughput methods for RNA m6A mapping. We further discuss the important roles of m6A modifiers in acute myeloid leukemia, and highlight the identification of potential inhibitors for AML treatment by targeting of m6A modifiers. Overall, this review provides a comprehensive summary of RNA m6A biology in acute myeloid leukemia.

14.
Biomolecules ; 12(8)2022 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-36009052

RESUMEN

Glial cells are the most abundant and widely distributed cells that maintain cerebral homeostasis in the central nervous system. They mainly include microglia, astrocytes, and the oligodendrocyte lineage cells. Moreover, glial cells may induce pathological changes, such as inflammatory responses, demyelination, and disruption of the blood-brain barrier, to regulate the occurrence and development of neurological diseases through various molecular mechanisms. Furthermore, RNA m6A modifications are involved in various pathological processes associated with glial cells. In this review, the roles of glial cells in physiological and pathological states, as well as advances in understanding the mechanisms by which glial cells regulate neurological diseases under RNA m6A modification, are summarized, hoping to provide new perspectives on the deeper mechanisms and potential therapeutic targets for neurological diseases.


Asunto(s)
Enfermedades del Sistema Nervioso , Neuroglía , Astrocitos/patología , Humanos , Enfermedades del Sistema Nervioso/genética , Enfermedades del Sistema Nervioso/patología , Oligodendroglía/fisiología , ARN
15.
Proc Natl Acad Sci U S A ; 119(33): e2203318119, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35939687

RESUMEN

γδ T cells are an abundant T cell population at the mucosa and are important in providing immune surveillance as well as maintaining tissue homeostasis. However, despite γδ T cells' origin in the thymus, detailed mechanisms regulating γδ T cell development remain poorly understood. N6-methyladenosine (m6A) represents one of the most common posttranscriptional modifications of messenger RNA (mRNA) in mammalian cells, but whether it plays a role in γδ T cell biology is still unclear. Here, we show that depletion of the m6A demethylase ALKBH5 in lymphocytes specifically induces an expansion of γδ T cells, which confers enhanced protection against gastrointestinal Salmonella typhimurium infection. Mechanistically, loss of ALKBH5 favors the development of γδ T cell precursors by increasing the abundance of m6A RNA modification in thymocytes, which further reduces the expression of several target genes including Notch signaling components Jagged1 and Notch2. As a result, impairment of Jagged1/Notch2 signaling contributes to enhanced proliferation and differentiation of γδ T cell precursors, leading to an expanded mature γδ T cell repertoire. Taken together, our results indicate a checkpoint role of ALKBH5 and m6A modification in the regulation of γδ T cell early development.


Asunto(s)
Desmetilasa de ARN, Homólogo 5 de AlkB , Linfocitos Intraepiteliales , ARN Mensajero , Desmetilasa de ARN, Homólogo 5 de AlkB/genética , Desmetilasa de ARN, Homólogo 5 de AlkB/metabolismo , Animales , Linfocitos Intraepiteliales/enzimología , Linfocitos Intraepiteliales/inmunología , Proteína Jagged-1/metabolismo , Ratones , Ratones Noqueados , ARN Mensajero/metabolismo , Receptor Notch2/metabolismo , Transducción de Señal/genética
16.
Mol Neurodegener ; 16(1): 70, 2021 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-34593014

RESUMEN

BACKGROUND: N6-methyladenosine (m6A) modification of RNA influences fundamental aspects of RNA metabolism and m6A dysregulation is implicated in various human diseases. In this study, we explored the potential role of RNA m6A modification in the pathogenesis of Alzheimer disease (AD). METHODS: We investigated the m6A modification and the expression of m6A regulators in the brain tissues of AD patients and determined the impact and underlying mechanism of manipulated expression of m6A levels on AD-related deficits both in vitro and in vivo. RESULTS: We found decreased neuronal m6A levels along with significantly reduced expression of m6A methyltransferase like 3 (METTL3) in AD brains. Interestingly, reduced neuronal m6A modification in the hippocampus caused by METTL3 knockdown led to significant memory deficits, accompanied by extensive synaptic loss and neuronal death along with multiple AD-related cellular alterations including oxidative stress and aberrant cell cycle events in vivo. Inhibition of oxidative stress or cell cycle alleviated shMettl3-induced apoptotic activation and neuronal damage in primary neurons. Restored m6A modification by inhibiting its demethylation in vitro rescued abnormal cell cycle events, neuronal deficits and death induced by METTL3 knockdown. Soluble Aß oligomers caused reduced METTL3 expression and METTL3 knockdown exacerbated while METTL3 overexpression rescued Aß-induced synaptic PSD95 loss in vitro. Importantly, METTL3 overexpression rescued Aß-induced synaptic damage and cognitive impairment in vivo. CONCLUSIONS: Collectively, these data suggested that METTL3 reduction-mediated m6A dysregulation likely contributes to neurodegeneration in AD which may be a therapeutic target for AD.


Asunto(s)
Enfermedad de Alzheimer , Adenosina/metabolismo , Enfermedad de Alzheimer/genética , Ciclo Celular , Humanos , Metiltransferasas/genética , Metiltransferasas/metabolismo , ARN
17.
Int J Mol Sci ; 22(20)2021 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-34681673

RESUMEN

Translocated in LipoSarcoma/Fused in Sarcoma (TLS/FUS) is a nuclear RNA binding protein whose mutations cause amyotrophic lateral sclerosis. TLS/FUS undergoes LLPS and forms membraneless particles with other proteins and nucleic acids. Interaction with RNA alters conformation of TLS/FUS, which affects binding with proteins, but the effect of m6A RNA modification on the TLS/FUS-RNA interaction remains elusive. Here, we investigated the binding specificity of TLS/FUS to m6A RNA fragments by RNA pull down assay, and elucidated that both wild type and ALS-related TLS/FUS mutants strongly bound to m6A modified RNAs. TLS/FUS formed cytoplasmic foci by treating hyperosmotic stress, but the cells transfected with m6A-modified RNAs had a smaller number of foci. Moreover, m6A-modified RNA transfection resulted in the cells obtaining higher resistance to the stress. In summary, we propose TLS/FUS as a novel candidate of m6A recognition protein, and m6A-modified RNA fragments diffuse cytoplasmic TLS/FUS foci and thereby enhance cell viability.


Asunto(s)
Adenosina/análogos & derivados , Proteína FUS de Unión a ARN/metabolismo , ARN/metabolismo , Adenosina/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Citoplasma/metabolismo , Sitios Genéticos , Humanos , Extracción Líquido-Líquido , Mutagénesis Sitio-Dirigida , Agregado de Proteínas/efectos de los fármacos , Unión Proteica , ARN/química , ARN/farmacología , ARN Largo no Codificante/química , Proteína FUS de Unión a ARN/química , Proteína FUS de Unión a ARN/genética , Sorbitol/farmacología
18.
Ann Hepatol ; 25: 100538, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34555511

RESUMEN

N6-methyladenosine (m6A) is the most thoroughly studied type of internal RNA modification, as this epigenetic modification is the most abundant in eukaryotic RNAs to date. This modification occurs in various types of RNAs and plays significant roles in dominant RNA-related processes, such as translation, splicing, export and degradation. These processes are catalyzed by three types of prominent enzymes: writers, erasers and readers. Increasing evidence has shown that m6A modification is vital for the regulation of gene expression, carcinogenesis, tumor progression and other abnormal changes, and recent studies have shown that m6A is important in the development of hepatocellular carcinoma (HCC). Herein, we summarize the nature and regulatory mechanisms of m6A modification, including its role in the pathogenesis of HCC and related chronic liver diseases. We also highlight the clinical significance and future strategies involving RNA m6A modifications in HCC.


Asunto(s)
Adenosina/análogos & derivados , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/patología , Adenosina/fisiología , Humanos
19.
Front Cell Dev Biol ; 9: 684398, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34150779

RESUMEN

Spermatogonial stem cells (SSCs) are the basis of spermatogenesis, and any damage to SSCs may result in spermatogenic disorder and male infertility. Chromium (Cr) (VI) is a proven toxin, mutagen, and carcinogen, perpetually detrimental to environmental organisms due to its intricate and enduring detoxification process in vivo. Despite this, the deleterious effects of Cr (VI) on SSCs and the underlying mechanisms remain poorly understood. In this study, we identified that Cr (VI) impaired male reproductive system in mouse testes and induced mitochondrial dynamic imbalance and mitophagy in SSCs/progenitors. Cr (VI) also downregulated the RNA N6-methyladenosine (m6A) modification levels in mitochondrial dynamic balance and mitophagy genes in SSCs/progenitors. Inspiringly, the toxic effects of Cr (VI) could be relieved by melatonin pretreatment. Melatonin alleviated Cr (VI)-induced damage to male reproductive system and autophagy in mouse testes. Melatonin also attenuated Cr (VI)-induced cell viability loss and reactive oxygen species (ROS) generation, as well as mitochondrial dynamic disorders and mitophagy in SSCs/progenitors. The protective roles of melatonin against Cr (VI)-induced mitophagy were exerted by restoration of METTL3-mediated RNA m6A modification and activation of mitochondrial fusion proteins MFN2 and OPA1, as well as inhibition of the mitophagy BNIP3/NIX receptor pathway. Thus, our study provides novel insights into the molecular mechanisms for RNA m6A modification underlying the gene regulatory network responsible for mitochondrial dynamic balance, and also lays new experimental groundwork for treatment of Cr (VI)-induced damage to male fertility.

20.
Cell Metab ; 33(6): 1221-1233.e11, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33910046

RESUMEN

The ever-increasing understanding of the complexity of factors and regulatory layers that contribute to immune evasion facilitates the development of immunotherapies. However, the diversity of malignant tumors limits many known mechanisms in specific genetic and epigenetic contexts, manifesting the need to discover general driver genes. Here, we have identified the m6A demethylase FTO as an essential epitranscriptomic regulator utilized by tumors to escape immune surveillance through regulation of glycolytic metabolism. We show that FTO-mediated m6A demethylation in tumor cells elevates the transcription factors c-Jun, JunB, and C/EBPß, which allows the rewiring of glycolytic metabolism. Fto knockdown impairs the glycolytic activity of tumor cells, which restores the function of CD8+ T cells, thereby inhibiting tumor growth. Furthermore, we developed a small-molecule compound, Dac51, that can inhibit the activity of FTO, block FTO-mediated immune evasion, and synergize with checkpoint blockade for better tumor control, suggesting reprogramming RNA epitranscriptome as a potential strategy for immunotherapy.


Asunto(s)
Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/inmunología , Regulación Neoplásica de la Expresión Génica , Vigilancia Inmunológica , Neoplasias/inmunología , Animales , Línea Celular Tumoral , Femenino , Melanoma Experimental , Ratones , Ratones Endogámicos C57BL
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