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1.
Nan Fang Yi Ke Da Xue Xue Bao ; 41(4): 567-573, 2021 Apr 20.
Artículo en Chino | MEDLINE | ID: mdl-33963717

RESUMEN

OBJECTIVE: To construct a corpus cavemosum smooth muscle cell (CCSMCs) line with TEAD1 knockout from diabetic rats with erectile dysfunction (ED) using CRISPR/Cas9 technology and explore the role of TEAD1 in phenotypic modulation of CCSMCs in diabetic rats with ED. OBJECTIVE: Models of diabetic ED were established in male Sprague-Dawley rats by intraperitoneal injection of streptozotocin. CCSMCs from the rat models were primarily cultured and identified with immunofluorescence assay. Three sgRNAs (sgRNA-1, sgRNA-2 and sgRNA-3) were transfected via lentiviral vectors into 293T cells to prepare the sgRNA-Cas9 lentivirus. CCSMCs from diabetic rats with ED were infected by the lentivirus, and the cellular expression of TEAD1 protein was detected using Western blotting. In CCSMCs infected with the sgRNA-Cas9 lentivirus (CCSMCs-sgRNA-2), or the empty lentiviral vector (CCSMCs-sgRNA-NC) and the blank control cells (CCSMCs-CK), the expressions of cellular phenotypic markers SMMHC, calponin and PCNA at the mRNA and protein levels were detected using real-time fluorescence quantitative RT-PCR (qRT-PCR) and Western blotting, respectively. OBJECTIVE: The primarily cultured CCSMCs from diabetic rats with ED showed a high α-SMA-positive rate of over 95%. The recombinant lentivirus of TEAD1-sgRNA was successfully packaged, and stable TEAD1-deficient CCSMC lines derived from diabetic rat with ED were obtained. Western blotting confirmed that the protein expression of TEAD1 in TEAD1-sgRNA-2 group was the lowest (P < 0.05), and this cell line was used in subsequent experiment. The results of qRT-PCR and Western blotting showed significantly up-regulated expressions of SMMHC and calponin (all P < 0.05) and down-regulated expression of PCNA (all P < 0.05) at both the mRNA and protein levels in TEAD1-deficient CCSMCs from diabetic rats with ED. OBJECTIVE: We successfully constructed a stable CCSMCs line with CRISPR/Cas9-mediated TEAD1 knockout from diabetic rats with ED. TEAD1 gene knockout can induce phenotype transformation of the CCSMCs from diabetic rats with ED from the synthetic to the contractile type.


Asunto(s)
Diabetes Mellitus Experimental , Disfunción Eréctil , Animales , Sistemas CRISPR-Cas , Proteínas de Unión al ADN/genética , Diabetes Mellitus Experimental/complicaciones , Disfunción Eréctil/genética , Humanos , Masculino , Miocitos del Músculo Liso , Proteínas Nucleares , Pene , Fenotipo , Ratas , Ratas Sprague-Dawley , Factores de Transcripción/genética
2.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33803949

RESUMEN

Invasive urothelial carcinomas of the bladder (UCB) characteristically show a loss of differentiation markers. The transcription factor Grainyhead-like 3 (GRHL3) plays an important role in the development and differentiation of normal urothelium. The contribution to UCB progression is still elusive. Differential expression of GRHL3 was assessed in normal human urothelium and in non-invasive and invasive bladder cancer cell lines. The contribution of GRHL3 to cell proliferation, viability and invasion in UCB cell lines was determined by gain- and loss-of-function assays in vitro and in an organ culture model using de-epithelialized porcine bladders. GRHL3 expression was detectable in normal human urothelial cells and showed significantly higher mRNA and protein levels in well-differentiated, non-invasive RT4 urothelial carcinoma cells compared to moderately differentiated RT112 cells. GRHL3 expression was absent in anaplastic and invasive T24 cells. Ectopic de novo expression of GRHL3 in T24 cells significantly impaired their migration and invasion properties in vitro and in organ culture. Its downregulation improved the invasive capacity of RT4 cells. The results indicate that GRHL3 may play a role in progression and metastasis in UCB. In addition, this work demonstrates that de-epithelialized porcine bladder organ culture can be a useful, standardized tool to assess the invasive capacity of cancer cells.


Asunto(s)
Carcinoma/genética , Proteínas de Unión al ADN/genética , Factores de Transcripción/genética , Neoplasias de la Vejiga Urinaria/genética , Urotelio/metabolismo , Animales , Carcinoma/patología , Carcinoma de Células Transicionales , Diferenciación Celular/genética , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Metástasis de la Neoplasia , Técnicas de Cultivo de Órganos , Porcinos , Neoplasias de la Vejiga Urinaria/patología , Urotelio/patología
3.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33803981

RESUMEN

Systemic mastocytosis (SM) is a hematologic neoplasm with abnormal accumulation of mast cells in various organ systems such as the bone marrow, other visceral organs and skin. So far, only little is known about epigenetic changes contributing to the pathogenesis of SM. In the current article, we provide an overview of epigenetic changes that may occur and be relevant to mastocytosis, including mutations in genes involved in epigenetic processes, such as TET2, DNMT3A and ASXL1, and global and gene-specific methylation patterns in neoplastic cells. Moreover, we discuss methylation-specific pathways and other epigenetic events that may trigger disease progression in mast cell neoplasms. Finally, we discuss epigenetic targets and the effects of epigenetic drugs, such as demethylating agents and BET-targeting drugs, on growth and viability of neoplastic mast cells. The definitive impact of these targets and the efficacy of epigenetic therapies in advanced SM need to be explored in future preclinical studies and clinical trials.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas/genética , Proteínas de Unión al ADN/genética , Neoplasias Hematológicas/genética , Mastocitosis Sistémica/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Represoras/genética , Epigénesis Genética/genética , Neoplasias Hematológicas/patología , Humanos , Mastocitos/patología , Mastocitosis Sistémica/patología , Mutación/genética
4.
Mol Biol (Mosk) ; 55(2): 318-337, 2021.
Artículo en Ruso | MEDLINE | ID: mdl-33871445

RESUMEN

The "Mendelian code" hypothesis postulates a relationship between Mendelian (monogenic) and common pathologies. In this hypothesis, polymorphisms in the genes of Mendelian diseases may have a significant contribution to predisposition to common diseases in which the same biochemical pathways may be involved. In this review a group of genes encoding various proteins participating in the DNA repair, with a particular focus on the BRCA1-associated genome surveillance complex (BASC), is presented through the prism of the "Mendelian code" hypothesis. Here we discuss (1) their main functions in the repair of DNA double-strand breaks (ATM, MRE11, NBN, RAD50, BRCA1, and BLM) and mismatch repair (MSH2, MSH6, MLH1, PMS2, RF-C, and PCNA); (2) the mitochondrial involvement of these proteins; (3) the involvement of BASC proteins in the development of an adaptive immune response. For 13 out of 16 BASC protein encoding genes, mutations leading to monogenic diseases have already been described; for 11, there are associations with common diseases or individual biological processes. Patients with mutations in the genes of the BASC complex and patients with severe combined immunodeficiency share similar symptoms. Polymorphisms within DNA repair genes may play a role in the development of common diseases through the involvement of the immune response. The pleiotropic effects of these genes suggest their participation in the development of various conditions, both in health and pathology.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas Nucleares , Proteína BRCA1/genética , Proteínas de Ciclo Celular/genética , Roturas del ADN de Doble Cadena , Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Humanos , Proteínas Nucleares/genética
5.
Nat Commun ; 12(1): 1988, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33790291

RESUMEN

Bacteria respond to environmental changes by inducing transcription of some genes and repressing others. Sialic acids, which coat human cell surfaces, are a nutrient source for pathogenic and commensal bacteria. The Escherichia coli GntR-type transcriptional repressor, NanR, regulates sialic acid metabolism, but the mechanism is unclear. Here, we demonstrate that three NanR dimers bind a (GGTATA)3-repeat operator cooperatively and with high affinity. Single-particle cryo-electron microscopy structures reveal the DNA-binding domain is reorganized to engage DNA, while three dimers assemble in close proximity across the (GGTATA)3-repeat operator. Such an interaction allows cooperative protein-protein interactions between NanR dimers via their N-terminal extensions. The effector, N-acetylneuraminate, binds NanR and attenuates the NanR-DNA interaction. The crystal structure of NanR in complex with N-acetylneuraminate reveals a domain rearrangement upon N-acetylneuraminate binding to lock NanR in a conformation that weakens DNA binding. Our data provide a molecular basis for the regulation of bacterial sialic acid metabolism.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Proteínas Represoras/metabolismo , Ácidos Siálicos/metabolismo , Regulación Alostérica , Secuencia de Bases , Sitios de Unión/genética , Cristalografía por Rayos X , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Modelos Moleculares , Ácido N-Acetilneuramínico/metabolismo , Motivos de Nucleótidos/genética , Unión Proteica , Conformación Proteica , Multimerización de Proteína , Proteínas Represoras/genética
6.
Zhonghua Bing Li Xue Za Zhi ; 50(4): 369-375, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33831997

RESUMEN

Objective: To analyze the expression of mismatch repair (MMR) proteins in colorectal cancers (CRC) and to evaluate the feasibility and potential pitfalls of immunohistochemistry (IHC) analysis for MMR. Methods: The IHC sections for MMR proteins were reviewed in 3 428 cases of resected CRC without neoadjuvant therapy at Tianjin Medical University Cancer Institute and Hospital from July 2014 to October 2018. For the cases with unclear MMR IHC results during the initial review, IHC staining was repeated and microsatellite instability (MSI) analysis was performed. Relationships between the expression of MMR proteins and MSI status as well as the clinicopathological parameters were analyzed. Results: IHC staining for MMR was repeated in 28 (0.8%) cases due to poor quality of original IHC sections. Inconsistent results between the original diagnosis and re-diagnosis were found in 119 (3.5%) cases, mainly resulting from PMS2 and MLH1. Finally, 261 (7.6%) cases of CRC showed mismatch repair deficiency (dMMR), mainly from the deficiency of both MLH1 and PMS2 (43.3%,113/261). In the 14 cases with MSI results, the concordant of MSI and MMR was 13 cases. In the 29 dMMR cases with next generation sequencing (NGS) results, the concordant of MSI-high and dMMR was 93.1%(27/29). The cases with inconsistent results between MSI and MMR showed negative expression of MSH6 or PMS2. Twenty-one CRC showed negative expression of MLH1 and partially positive (or weak positive) expression of PMS2, or negative expression of MSH2 and partially positive (or weak positive) expression of MSH6. Among the 19 cases with MSI results, 16 cases were MSI-high, two cases were MSI-low, and one case was microsatellite stable. Compared with mismatch repair proficiency (pMMR), dMMR was more frequently detected in female patients younger than 50 years old, with family history, at early stage (Ⅰ-Ⅱ) CRC, and in the tumors from right colon,with poor differentiation, or mucinous adenocarcinoma/signet ring cell carcinoma (all P<0.05). Conclusions: At present, IHC staining is a clinically effective and convenient method to detect MMR expression, but the operating process and result assessment remain variable and need to be standardized. MSI analysis can be performed in the difficult-to-evaluate cases for MMR to enhance prognostic evaluation and treatment option.


Asunto(s)
Neoplasias Colorrectales , Reparación de la Incompatibilidad de ADN , Neoplasias Colorrectales/genética , Reparación de la Incompatibilidad de ADN/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Femenino , Humanos , Inestabilidad de Microsatélites , Persona de Mediana Edad , Endonucleasa PMS2 de Reparación del Emparejamiento Incorrecto/genética , Endonucleasa PMS2 de Reparación del Emparejamiento Incorrecto/metabolismo , Homólogo 1 de la Proteína MutL/genética , Homólogo 1 de la Proteína MutL/metabolismo , Proteína 2 Homóloga a MutS/metabolismo , Estudios Retrospectivos
7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(2): 450-455, 2021 Apr.
Artículo en Chino | MEDLINE | ID: mdl-33812414

RESUMEN

OBJECTIVE: To investigate the relationship between acute myeloid leukemia (AML) patients ASXL2, ZBTB7A gene mutations and the prognosis. METHODS: 42 AML Patients treated in our hospital from January 2014 to January 2016 were selected and ASXL2 and ZBTB7A genes of their bone marrow samples were sequenced, the genetic characteristics and prognosis of core-binding factor-AML(CBF-AML) patients with ASXL2 and ZBTB7A mutations were analyzed. RESULTS: ASXL2 (33.3%) and ZBTB7A (9.5%) mutations were found in t (8; 21) AML patients. Compared with wild-type, patients with ASXL2 mutations showed significantly higher white blood cell count at diagnosis ï¼»(9.49±1.85)×109/L vs (8.3±1.14)×109/L,P=0.03ï¼½ and lower frequency of sex chromosome deletions (21.43% vs 71.43%, P=0.02), respectively. ASXL2 mutation showed mutually exclusive with ASXL1 mutation (P=0.035). The proportion of chromatin modifier gene ATRX and BCOR mutations was higher in patients with ASXL2 mutation (P=0.032, P=0.005).ASXL2 and ZBTB7A mutations showed no significant effect to overall survival or event-free survival rate in patients with AML. CONCLUSION: ASXL2 and ZBTB7A mutations are frequently found in t (8; 21) AML patients. The mutation of ASXL2 and ZBTB7A genes shows no significant effect on the prognosis of AML patients.


Asunto(s)
Proteínas de Unión al ADN , Leucemia Mieloide Aguda , Línea Celular Tumoral , Proteínas de Unión al ADN/genética , Humanos , Leucemia Mieloide Aguda/genética , Mutación , Proteínas de Fusión Oncogénica/genética , Pronóstico , Proteínas Represoras/genética , Factores de Transcripción/genética
8.
Nat Commun ; 12(1): 2398, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33893278

RESUMEN

Arginine plays diverse roles in cellular physiology. As a semi-essential amino acid, arginine deprivation has been used to target cancers with arginine synthesis deficiency. Arginine-deprived cancer cells exhibit mitochondrial dysfunction, transcriptional reprogramming and eventual cell death. In this study, we show in prostate cancer cells that arginine acts as an epigenetic regulator to modulate histone acetylation, leading to global upregulation of nuclear-encoded oxidative phosphorylation (OXPHOS) genes. TEAD4 is retained in the nucleus by arginine, enhancing its recruitment to the promoter/enhancer regions of OXPHOS genes and mediating coordinated upregulation in a YAP1-independent but mTOR-dependent manner. Arginine also activates the expression of lysine acetyl-transferases and increases overall levels of acetylated histones and acetyl-CoA, facilitating TEAD4 recruitment. Silencing of TEAD4 suppresses OXPHOS functions and prostate cancer cell growth in vitro and in vivo. Given the strong correlation of TEAD4 expression and prostate carcinogenesis, targeting TEAD4 may be beneficially used to enhance arginine-deprivation therapy and prostate cancer therapy.


Asunto(s)
Arginina/farmacología , Proteínas de Unión al ADN/genética , Epigénesis Genética/efectos de los fármacos , Epigenómica/métodos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas Musculares/genética , Fosforilación Oxidativa/efectos de los fármacos , Neoplasias de la Próstata/genética , Factores de Transcripción/genética , Animales , Arginina/metabolismo , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Proteínas de Unión al ADN/metabolismo , Humanos , Masculino , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/genética , Mitocondrias/metabolismo , Proteínas Musculares/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Factores de Transcripción/metabolismo
9.
Nat Commun ; 12(1): 2428, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33893291

RESUMEN

Heterochromatin is a critical chromatin compartment, whose integrity governs genome stability and cell fate transitions. How heterochromatin features, including higher-order chromatin folding and histone modifications associated with transcriptional silencing, are maintained following a genotoxic stress challenge is unknown. Here, we establish a system for targeting UV damage to pericentric heterochromatin in mammalian cells and for tracking the heterochromatin response to UV in real time. We uncover profound heterochromatin compaction changes during repair, orchestrated by the UV damage sensor DDB2, which stimulates linker histone displacement from chromatin. Despite massive heterochromatin unfolding, heterochromatin-specific histone modifications and transcriptional silencing are maintained. We unveil a central role for the methyltransferase SETDB1 in the maintenance of heterochromatic histone marks after UV. SETDB1 coordinates histone methylation with new histone deposition in damaged heterochromatin, thus protecting cells from genome instability. Our data shed light on fundamental molecular mechanisms safeguarding higher-order chromatin integrity following DNA damage.


Asunto(s)
Daño del ADN , Reparación del ADN , ADN/genética , Heterocromatina/genética , Animales , Línea Celular Tumoral , Ensamble y Desensamble de Cromatina/genética , ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Heterocromatina/efectos de la radiación , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/metabolismo , Humanos , Células MCF-7 , Metilación , Ratones , Células 3T3 NIH , Rayos Ultravioleta
10.
Int J Mol Sci ; 22(6)2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33806835

RESUMEN

Chromodomain helicase domain 8 (CHD8) is one of the most frequently mutated and most penetrant genes in the autism spectrum disorder (ASD). Individuals with CHD8 mutations show leading symptoms of autism, macrocephaly, and facial dysmorphisms. The molecular and cellular mechanisms underpinning the early onset and development of these symptoms are still poorly understood and prevent timely and more efficient therapies of patients. Progress in this area will require an understanding of "when, why and how cells deviate from their normal trajectories". High-throughput single-cell RNA sequencing (sc-RNAseq) directly quantifies information-bearing RNA molecules that enact each cell's biological identity. Here, we discuss recent insights from sc-RNAseq of CRISPR/Cas9-editing of Chd8/CHD8 during mouse neocorticogenesis and human cerebral organoids. Given that the deregulation of the balance between excitation and inhibition (E/I balance) in cortical and subcortical circuits is thought to represent a major etiopathogenetic mechanism in ASD, we focus on the question of whether, and to what degree, results from current sc-RNAseq studies support this hypothesis. Beyond that, we discuss the pros and cons of these approaches and further steps to be taken to harvest the full potential of these transformative techniques.


Asunto(s)
Trastorno Autístico/etiología , Trastorno Autístico/metabolismo , Proteínas de Unión al ADN/genética , Susceptibilidad a Enfermedades , Factores de Transcripción/genética , Transcriptoma , Animales , Trastorno Autístico/psicología , Encéfalo/metabolismo , Encéfalo/fisiopatología , Proteínas de Unión al ADN/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Mutación , Neurogénesis , Análisis de la Célula Individual/métodos , Factores de Transcripción/metabolismo
11.
Science ; 372(6539): 292-295, 2021 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-33859035

RESUMEN

Gene-regulatory networks achieve complex mappings of inputs to outputs through mechanisms that are poorly understood. We found that in the galactose-responsive pathway in Saccharomyces cerevisiae, the decision to activate the transcription of genes encoding pathway components is controlled independently from the expression level, resulting in behavior resembling that of a mechanical dimmer switch. This was not a direct result of chromatin regulation or combinatorial control at galactose-responsive promoters; rather, this behavior was achieved by hierarchical regulation of the expression and activity of a single transcription factor. Hierarchical regulation is ubiquitous, and thus dimmer switch regulation is likely a key feature of many biological systems. Dimmer switch gene regulation may allow cells to fine-tune their responses to multi-input environments on both physiological and evolutionary time scales.


Asunto(s)
Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Galactosa/metabolismo , Regulación Fúngica de la Expresión Génica , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Galactoquinasa/genética , Galactoquinasa/metabolismo , Redes Reguladoras de Genes , Aptitud Genética , Glucosa/metabolismo , Redes y Vías Metabólicas/genética , Modelos Genéticos , Regiones Promotoras Genéticas , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Saccharomyces cerevisiae/crecimiento & desarrollo , Transcripción Genética
12.
Medicine (Baltimore) ; 100(14): e25344, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33832110

RESUMEN

ABSTRACT: Excision repair cross complementing 1 (ERCC1), ribonucleotide reductase M1 (RRM1), ß-tubulin III (TUBB3), thymidylate synthetase (TYMS), and topoisomerase IIα (TOP2A) genes have been shown to be associated with the pathogenesis and prognosis of various types of carcinomas; however, their roles in breast cancer have not been fully validated. In this study, we evaluated the correlations among these biomarkers and the associations between their expression intensity and the clinicopathological characteristics to investigate whether the above genes are underlying biomarkers for patients with breast cancer.Ninety-seven tissue specimens collected from breast cancer patients. The expression levels of these biomarkers were measured by the multiplex branched DNA liquidchip (MBL) technology and clinicopathological characteristics were collected simultaneously.The expression levels of ERCC1, TUBB3, TYMS, and TOP2A were significantly associated with the characteristics of menopausal status, tumor size, lymph node metastasis, hormone receptor status, triple-negative status, Ki-67 index, and epidermal growth factor receptor. The expression intensity of ERCC1 negatively associated with that of TUBB3 and TYMS, and positively associated with that of RRM1. The expression intensity of TOP2A positively associated with that of TYMS. Hierarchical clustering analysis and difference test indicated that breast cancer with higher levels of TUBB3, TYMS, and TOP2A, as well as lower levels of ERCC1 and RRM1 tended to have higher histological grade and Ki-67 index.Our studies showed that ERCC1, TYMS, TUBB3, and TOP2A may be potential biomarkers for prognosis and individualized chemotherapy guidance, while there may be interactions between ERCC1 and RRM1, or TUBB3, or TYMS, as well as between TOP2A and TYMS in pathogenesis and development of breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Adulto , Anciano , Biomarcadores de Tumor , ADN-Topoisomerasas de Tipo II/genética , Proteínas de Unión al ADN/genética , Receptores ErbB/biosíntesis , Femenino , Expresión Génica , Humanos , Antígeno Ki-67/biosíntesis , Metástasis Linfática/patología , Menopausia/fisiología , Persona de Mediana Edad , Ribonucleótido Reductasas/genética , Timidilato Sintasa/genética , Neoplasias de la Mama Triple Negativas/patología , Carga Tumoral
13.
Nat Commun ; 12(1): 2220, 2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33850123

RESUMEN

The acidic activation domain (AD) of yeast transcription factor Gal4 plays a dual role in transcription repression and activation through binding to Gal80 repressor and Mediator subunit Med15. The activation function of Gal4 arises from two hydrophobic regions within the 40-residue AD. We show by NMR that each AD region binds the Mediator subunit Med15 using a "fuzzy" protein interface. Remarkably, comparison of chemical shift perturbations shows that Gal4 and Gcn4, two intrinsically disordered ADs of different sequence, interact nearly identically with Med15. The finding that two ADs of different sequence use an identical fuzzy binding mechanism shows a common sequence-independent mechanism for AD-Mediator binding, similar to interactions within a hydrophobic cloud. In contrast, the same region of Gal4 AD interacts strongly with Gal80 via a distinct structured complex, implying that the structured binding partner of an intrinsically disordered protein dictates the type of protein-protein interaction.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Proteínas de Unión al ADN/metabolismo , Complejo Mediador/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/química , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Complejo Mediador/química , Complejo Mediador/genética , Metiltransferasas/química , Metiltransferasas/metabolismo , Modelos Moleculares , Dominios y Motivos de Interacción de Proteínas , Proteínas Represoras/química , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Factores de Transcripción/genética
14.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(2): 420-424, 2021 Feb 22.
Artículo en Chino | MEDLINE | ID: mdl-33879920

RESUMEN

The methylation of cytosine is one of the most fundamental epigenetic modifications in mammalian genomes, and is involved in multiple crucial processes including gene expression, cell differentiation, embryo development and oncogenesis. In the past, DNA methylation was thought to be an irreversible process, which could only be diluted passively through DNA replication. It is now becoming increa-singly obvious that DNA demethylation can be an active process and plays a crucial role in biological processes. Ten eleven translocation (TET) proteins are the key factors modulating DNA demethylation. This family contains three members: TET1, TET2 and TET3. Although three TET proteins have relatively conserved catalytic domains, their roles in organisms are not repeated, and their expression has significant cell/organ specificity. TET1 is mainly expressed in embryonic stem cells, TET2 is mainly expressed in hematopoietic system, and TET3 is widely expressed in cerebellum, cortex and hippocampus. This family catalyzes 5-methylcytosine to 5-hydroxymethylcytosine and other oxidative products, reactivates silenced-gene expression, in turn maintains stem cell pluripotency and regulates lineage specification. With the development of tissue engineering, organ transplantation, autologous tissue transplantation and artificial prosthesis have been widely used in clinical treatment, but these technologies have limitations. Regenerative medicine, which uses stem cells and stem cell related factors for treatment, may provide alternative therapeutic strategies for multiple diseases. Among all kinds of human stem cells, adipose-derived stem cells (ADSCs) are the most prospective stem cell lineage since they have no ethical issues and can be easily obtained with large quantities. To date, ADSCs have been shown to have strong proli-feration capacity, secrete numerous soluble factors and have multipotent differentiation ability. However, the underlying mechanism of the proliferation, secretion, acquired pluripotency, and lineage specific differentiation of ADSCs are still largely unknown. Some studies have explored the role of epigenetic regulation and TET protein in embryonic stem cells, but little is known about its role in ADSCs. By studying the roles of TET proteins and 5-hydroxymethylcytosine in ADSCs, we could provide new theoretical foundation for the clinical application of ADSCs and the stem cell-based therapy. In the future, combined with bioprinting technology, ADSCs may be used in tissue and organ regeneration, plastic surgery reconstruction and other broader fields.


Asunto(s)
5-Metilcitosina , Epigénesis Genética , 5-Metilcitosina/análogos & derivados , Animales , Metilación de ADN , Proteínas de Unión al ADN/genética , Humanos , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Estudios Prospectivos , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Medicina Regenerativa , Células Madre/metabolismo
15.
Front Med ; 15(2): 302-312, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33855678

RESUMEN

Cullin-RING E3 ubiquitin ligase (CRL)-4 is a member of the large CRL family in eukaryotes. It plays important roles in a wide range of cellular processes, organismal development, and physiological and pathological conditions. DDB1- and CUL4-associated factor 8 (DCAF8) is a WD40 repeat-containing protein, which serves as a substrate receptor for CRL4. The physiological role of DCAF8 is unknown. In this study, we constructed Dcaf8 knockout mice. Homozygous mice were viable with no noticeable abnormalities. However, the fertility of Dcaf8-deficient male mice was markedly impaired, consistent with the high expression of DCAF8 in adult mouse testis. Sperm movement characteristics, including progressive motility, path velocity, progressive velocity, and track speed, were significantly lower in Dcaf8 knockout mice than in wild-type (WT) mice. However, the total motility was similar between WT and Dcaf8 knockout sperm. More than 40% of spermatids in Dcaf8 knockout mice showed pronounced morphological abnormalities with typical bent head malformation. The acrosome and nucleus of Dcaf8 knockout sperm looked similar to those of WT sperm. In vitro tests showed that the fertilization rate of Dcaf8 knockout mice was significantly reduced. The results demonstrated that DCAF8 plays a critical role in spermatogenesis, and DCAF8 is a key component of CRL4 function in the reproductive system.


Asunto(s)
Factor VIII , Espermatogénesis , Animales , Proteínas Cullin/genética , Proteínas de Unión al ADN/genética , Masculino , Ratones , Ratones Noqueados , Espermatogénesis/genética , Ubiquitina-Proteína Ligasas
16.
Int J Mol Sci ; 22(6)2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33808599

RESUMEN

The study of metabolic deregulation in myeloid malignancies has led to the investigation of metabolic-targeted therapies considering that cells undergoing leukemic transformation have excessive energy demands for growth and proliferation. However, the most difficult challenge in agents targeting metabolism is to determine a window of therapeutic opportunities between normal and neoplastic cells, considering that all or most of the metabolic pathways important for cancer ontogeny may also regulate physiological cell functions. Targeted therapies have used the properties of leukemic cells to produce altered metabolic products when mutated. This is the case of IDH1/2 mutations generating the abnormal conversion of α-ketoglutarate (KG) to 2-hydroxyglutarate, an oncometabolite inhibiting KG-dependent enzymes, such as the TET family of genes (pivotal in characterizing leukemia cells either by mutations, e.g., TET2, or by altered expression, e.g., TET1/2/3). Additional observations derive from the high sensitivity of leukemic cells to oxidative phosphorylation and its amelioration using BCL-2 inhibitors (Venetoclax) or by disrupting the mitochondrial respiration. More recently, nicotinamide metabolism has been described to mediate resistance to Venetoclax in patients with acute myeloid leukemia. Herein, we will provide an overview of the latest research on the link between metabolic pathways interactome and leukemogenesis with a comprehensive analysis of the metabolic consequences of driver genetic lesions and exemplificative druggable pathways.


Asunto(s)
Biomarcadores de Tumor , Susceptibilidad a Enfermedades , Metabolismo Energético , Mutación , Trastornos Mieloproliferativos/etiología , Trastornos Mieloproliferativos/metabolismo , Animales , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Redes y Vías Metabólicas , Metabolómica , Trastornos Mieloproliferativos/patología , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo
17.
Mol Cell ; 81(6): 1126-1127, 2021 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-33740471
18.
Am J Hum Genet ; 108(4): 749-756, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33743206

RESUMEN

The DNA damage-binding protein 1 (DDB1) is part of the CUL4-DDB1 ubiquitin E3 ligase complex (CRL4), which is essential for DNA repair, chromatin remodeling, DNA replication, and signal transduction. Loss-of-function variants in genes encoding the complex components CUL4 and PHIP have been reported to cause syndromic intellectual disability with hypotonia and obesity, but no phenotype has been reported in association with DDB1 variants. Here, we report eight unrelated individuals, identified through Matchmaker Exchange, with de novo monoallelic variants in DDB1, including one recurrent variant in four individuals. The affected individuals have a consistent phenotype of hypotonia, mild to moderate intellectual disability, and similar facies, including horizontal or slightly bowed eyebrows, deep-set eyes, full cheeks, a short nose, and large, fleshy and forward-facing earlobes, demonstrated in the composite face generated from the cohort. Digital anomalies, including brachydactyly and syndactyly, were common. Three older individuals have obesity. We show that cells derived from affected individuals have altered DDB1 function resulting in abnormal DNA damage signatures and histone methylation following UV-induced DNA damage. Overall, our study adds to the growing family of neurodevelopmental phenotypes mediated by disruption of the CRL4 ubiquitin ligase pathway and begins to delineate the phenotypic and molecular effects of DDB1 misregulation.


Asunto(s)
Alelos , Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Mutación , Trastornos del Neurodesarrollo/genética , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Fenotipo , Síndrome
19.
Mol Med Rep ; 23(5)2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33760147

RESUMEN

Hepatocellular carcinoma (HCC) is characterized by a poor prognosis because of its insensitivity to radiation and chemotherapy. Recently, circular RNAs (circRNAs) have been found to serve important roles in hepatocellular carcinogenesis. circ­CCT3, a novel circRNA, was screened from the differential tissue expression results of a circRNA microarray. Relative expression levels of circ­CCT3 in specimens and cell lines were evaluated by reverse transcription­quantitative PCR and the relationship between circ­CCT3 and prognosis was analyzed by Kaplan­Meier curves. The oncogenic role of circ­CCT3 was confirmed in HCC cells through a cell counting kit­8 (CCK­8) assay, a colony formation assay, acridine orange/ethidium bromide double fluorescence staining, flow cytometry, a wound­healing assay and a Transwell assay. Bioinformatics prediction and luciferase reporter assays validated that circ­CCT3 facilitated HCC progression through the miR­1287­5p/TEA domain transcription factor 1 (TEAD1) axis. TEAD1 could then directly activate patched 1 and lysyl oxidase transcription, as analyzed by chromatin immunoprecipitation and luciferase reporter assays. The present study identified a novel circRNA, circ­CCT3, which may be used as a potential therapeutic target for HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Proteínas de Unión al ADN/genética , Neoplasias Hepáticas/genética , MicroARNs/genética , Proteínas Nucleares/genética , Receptor Patched-1/genética , ARN Circular/genética , Factores de Transcripción/genética , Adulto , Anciano , Apoptosis/genética , Carcinogénesis/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular/genética , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Proteína-Lisina 6-Oxidasa/genética
20.
Life Sci ; 276: 119322, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33711386

RESUMEN

ATAD2 is a promising oncoprotein with tumor-promoting functions in many cancers. It is a valid cancer drug-target and a potential cancer-biomarker for multiple malignancies. As a cancer/testis antigen (CTA), ATAD2 could also be a probable candidate for immunotherapy. It is a unique CTA that belongs to both AAA+ ATPase and bromodomain family proteins. Since 2007, several research groups have been reported on the pleiotropic oncogenic functions of ATAD2 in diverse signaling pathways, including Rb/E2F-cMyc pathway, steroid hormone signaling pathway, p53 and p38-MAPK-mediated apoptotic pathway, AKT pathway, hedgehog signaling pathway, HIF1α signaling pathway, and Epithelial to Mesenchymal Transition (EMT) pathway in various cancers. In all these pathways, ATAD2 participates in chromatin dynamics, DNA replication, and gene transcription, demonstrating its role as an epigenetic reader and transcription factor or coactivator to promote tumorigenesis. However, despite the progress, an overall mechanism of ATAD2-mediated oncogenesis in diverse origin is elusive. In this review, we summarize the accumulated evidence to envision the overall ATAD2 signaling networks during carcinogenesis and highlight the area where missing links await further research. Besides, the structure-function aspect of ATAD2 is also discussed. Since the efforts have already been initiated to explore targeted drug molecules and RNA-based therapeutic alternatives against ATAD2, their potency and prospects have been elucidated. Together, we believe this is a well-rounded review on ATAD2, facilitating a new drift in ATAD2 research, essential for its clinical implication as a biomarker and/or cancer drug-target.


Asunto(s)
ATPasas Asociadas con Actividades Celulares Diversas/metabolismo , Biomarcadores de Tumor/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación Neoplásica de la Expresión Génica , Terapia Molecular Dirigida , Neoplasias/patología , ATPasas Asociadas con Actividades Celulares Diversas/genética , Biomarcadores de Tumor/genética , Proteínas de Unión al ADN/genética , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo
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