Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Acta Pharmacol Sin ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902501

RESUMO

The impairment of blood-brain barrier (BBB) integrity is the pathological basis of hemorrhage transformation and vasogenic edema following thrombolysis and endovascular therapy. There is no approved drug in the clinic to reduce BBB damage after acute ischemic stroke (AIS). Glial growth factor 2 (GGF2), a recombinant version of neuregulin-1ß that can stimulates glial cell proliferation and differentiation, has been shown to alleviate free radical release from activated microglial cells. We previously found that activated microglia and proinflammatory factors could disrupt BBB after AIS. In this study we investigated the effects of GGF2 on AIS-induced BBB damage as well as the underlying mechanisms. Mouse middle cerebral artery occlusion model was established: mice received a 90-min ischemia and 22.5 h reperfusion (I/R), and were treated with GGF2 (2.5, 12.5, 50 ng/kg, i.v.) before the reperfusion. We showed that GGF2 treatment dose-dependently decreased I/R-induced BBB damage detected by Evans blue (EB) and immunoglobulin G (IgG) leakage, and tight junction protein occludin degradation. In addition, we found that GGF2 dose-dependently reversed AIS-induced upregulation of vesicular transcytosis increase, caveolin-1 (Cav-1) as well as downregulation of major facilitator superfamily domain containing 2a (Mfsd2a). Moreover, GGF2 decreased I/R-induced upregulation of PDZ and LIM domain protein 5 (Pdlim5), an adaptor protein that played an important role in BBB damage after AIS. In addition, GGF2 significantly alleviated I/R-induced reduction of YAP and TAZ, microglial cell activation and upregulation of inflammatory factors. Together, these results demonstrate that GGF2 treatment alleviates the I/R-compromised integrity of BBB by inhibiting Mfsd2a/Cav-1-mediated transcellular permeability and Pdlim5/YAP/TAZ-mediated paracellular permeability.

2.
Gynecol Obstet Invest ; 84(5): 503-511, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31117092

RESUMO

BACKGROUND: There are few studies on the relative factors related to postoperative recurrence. OBJECTIVES: To compare the outcomes of pelvic floor reconstruction involving Herniamesh mesh and biological grafts and to investigate the correlative factors of postoperative recurrence. METHOD: Two hundred and thirty-two patients were randomly divided into 2 groups: Herniamesh mesh group (117) and biological graft group (115). Follow-ups for 6 months and 1 year after the surgery. The primary outcomes were recurrence, perioperative complications. Secondary outcome was a questionnaire about the life habits associated with relapse. RESULTS: The recurrence rate at 6 months or 1 year did not differ substantially between the 2 groups (p = 0.787 and 0.968, respectively). Adverse events occurred with significantly different frequencies over 1 year (p = 0.005). Twelve factors were investigated and analyzed by logistic regression analysis. It showed that recurrence had a strong association with a long-term vegetarian diet (OR 0.283, 95% CI 0.117-0.683), long-term soybean product diet (OR 8.010, 95% CI 2.514-25.523), and vaginal intercourse (OR 5.154, 95% CI 1.461-18.184). CONCLUSIONS: The surgical recurrence rate for the mesh was similar to biological grafts at short-term follow-up. Eating soy products often and vaginal intercourse after surgery can reduce recurrence.


Assuntos
Prolapso de Órgão Pélvico/cirurgia , Pelve/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Telas Cirúrgicas , Transplantes , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Método Simples-Cego , Inquéritos e Questionários , Resultado do Tratamento
3.
BMC Cancer ; 18(1): 27, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29301498

RESUMO

BACKGROUND: Lin28B and its paralog Lin28A are small RNA binding proteins that have similar inhibitory effects, although they target separate steps in the maturation of let-7 miRNAs in mammalian cells. Because Lin28B participates in the promotion and development of tumors mostly by blocking the let-7 tumor suppressor family members, we sought to explore the associated mechanisms to gain insights into how Lin28B might be decreased in human cancer cells to increase let-7 levels and reverse malignancy. RESULTS: We demonstrated that the histone acetyltransferase PCAF, via its cold shock domain, directly interacts with and subsequently acetylates Lin28B in lung adenocarcinoma-derived H1299 cells. RT-qPCR assays showed that both let-7a-1 and let-7g were increased in PCAF-transfected H1299 cells. Lin28B is acetylated by ectopic PCAF and translocates from the nucleus to the cytoplasm in H1299 cells. CONCLUSIONS: The effects of acetylated Lin28B on let-7a-1 and let-7g are similar to that of stable knockdown of Lin28B in H1299 cells. The new role of PCAF in mediating Lin28B acetylation and the specific release of its target microRNAs in H1299 cells may shed light on the potential application of let-7 in the clinical treatment of lung cancer patients.


Assuntos
Adenocarcinoma/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição de p300-CBP/genética , Acetilação , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Ligação Proteica
4.
Biochim Biophys Acta ; 1859(2): 348-54, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26704017

RESUMO

Mammalian Sirtuin proteins (SIRTs) are homologs of yeast Sir2, and characterized as class III histone deacetylases of NAD(+) dependence. Unlike their lower counterparts that are directly involved in the extending of lifespan, mammalian SIRTs mainly function in metabolism and cellular homeostasis, among them, SIRT7 is the least understood. SIRT7 is localized in the nucleus and rich in nucleoli associated with RNA polymerase I, and correlated with cell proliferation. In contrast, SIRT7 has recently been demonstrated to specifically deacetylate H3K18ac in the chromatin, and in most cases represses proliferation. Although MicroRNA as miR-125b has been reported to down-regulate SIRT7 by binding to its 3'UTR, however, how SIRT7 gene is regulated remains unclear. Here, we identified the transcription initiation site of human SIRT7 gene at the upstream 23rd A nucleotide respective to the translational codon, and the SIRT7 is a TATA-less and initiator-less gene. The sequences in the upstream region between -256 and -129 bp are identical with important functions in the three species detected. A C/EBPα responding element is found that binds both C/EBPα and C/EBPß in vitro. We showed TSA induced SIRT7 gene transcription and only the HDAC3, but not its catalytic domain depleted mutant, interacted with C/EBPα to occupy the C/EBPα element and repressed SIRT7 gene in the hepatocellular carcinoma cells. To our knowledge, this is the first report on the regulation mechanism of SIRT7 gene, in which, HDAC3 collaborated with C/EBPα to occupy its responding element in the upstream region of SIRT7 gene and repressed its expression in human cells.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/genética , Carcinoma Hepatocelular/genética , Histona Desacetilases/genética , Neoplasias Hepáticas/genética , Sirtuínas/genética , Regiões 3' não Traduzidas , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/biossíntese , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Cromatina/genética , Histona Desacetilases/biossíntese , Humanos , Neoplasias Hepáticas/patologia , Regiões Promotoras Genéticas , Sirtuínas/biossíntese
5.
PLoS Biol ; 12(12): e1002026, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25535969

RESUMO

Histone lysine (K) residues, which are modified by methyl- and acetyl-transferases, diversely regulate RNA synthesis. Unlike the ubiquitously activating effect of histone K acetylation, the effects of histone K methylation vary with the number of methyl groups added and with the position of these groups in the histone tails. Histone K demethylases (KDMs) counteract the activity of methyl-transferases and remove methyl group(s) from specific K residues in histones. KDM3A (also known as JHDM2A or JMJD1A) is an H3K9me2/1 demethylase. KDM3A performs diverse functions via the regulation of its associated genes, which are involved in spermatogenesis, metabolism, and cell differentiation. However, the mechanism by which the activity of KDM3A is regulated is largely unknown. Here, we demonstrated that mitogen- and stress-activated protein kinase 1 (MSK1) specifically phosphorylates KDM3A at Ser264 (p-KDM3A), which is enriched in the regulatory regions of gene loci in the human genome. p-KDM3A directly interacts with and is recruited by the transcription factor Stat1 to activate p-KDM3A target genes under heat shock conditions. The demethylation of H3K9me2 at the Stat1 binding site specifically depends on the co-expression of p-KDM3A in the heat-shocked cells. In contrast to heat shock, IFN-γ treatment does not phosphorylate KDM3A via MSK1, thereby abrogating its downstream effects. To our knowledge, this is the first evidence that a KDM can be modified via phosphorylation to determine its specific binding to target genes in response to thermal stress.


Assuntos
Regulação da Expressão Gênica , Resposta ao Choque Térmico/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Montagem e Desmontagem da Cromatina/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Genoma Humano , Proteínas de Choque Térmico HSP90/metabolismo , Resposta ao Choque Térmico/efeitos dos fármacos , Humanos , Interferon gama/farmacologia , Histona Desmetilases com o Domínio Jumonji/química , Células Jurkat , Modelos Biológicos , Dados de Sequência Molecular , Fosforilação/efeitos dos fármacos , Fosfosserina/metabolismo , Ligação Proteica/efeitos dos fármacos , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética
6.
Biochim Biophys Acta ; 1843(6): 1188-95, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24631505

RESUMO

Lin28 is a small RNA-binding protein that plays an important role in regulating developmental timing, stem cell reprogramming, and oncogenesis. However, the significance of the effect of post-translational modifications on Lin28 activity is not fully understood. In this study, we demonstrated that PCAF directly interacted with and acetylated Lin28. We also showed that the acetylation of Lin28 can be specifically reversed by the deacetylase SIRT1. These findings suggest that the PCAF/SIRT1 balance plays an important role in regulating Lin28 activity. Furthermore, we found that the cold shock domain of Lin28 is the major target of PCAF-mediated acetylation, which leads to a severe reduction in the Lin28 protein levels and an increase in the level of mature let-7a. This study provides the first demonstration that post-translational modification regulates Lin28 activity during let-7a biogenesis and sheds light on the regulation of Lin28 in ES cells and carcinogenesis.


Assuntos
Processamento de Proteína Pós-Traducional , Proteínas de Ligação a RNA/metabolismo , Sirtuína 1/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Acetilação , Western Blotting , Imunofluorescência , Células HEK293 , Humanos , Imunoprecipitação , Luciferases/metabolismo , Mutagênese Sítio-Dirigida , Mutação/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sirtuína 1/genética , Fatores de Transcrição de p300-CBP/genética
7.
Acta Pharmacol Sin ; 34(5): 667-73, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23503475

RESUMO

AIM: Ubiquitin-proteasome system (UPS) and autophagosome-lysosome pathway (ALP) are the most important machineries responsible for protein degradation in Parkinson's disease (PD). The aim of this study is to investigate the adaptive alterations in autophagy upon proteasome inhibition in dopaminergic neurons in vitro and in vivo. METHODS: Human dopaminergic neuroblastoma SH-SY5Y cells were treated with the proteasome inhibitor lactacystin (5 µmol/L) for 5, 12, or 24 h. The expression of autophagy-related proteins in the cells was detected with immunoblotting. UPS-impaired mouse model of PD was established by microinjection of lactacystin (2 µg) into the left hemisphere of C57BL/6 mice that were sacrificed 2 or 4 weeks later. The midbrain tissues were dissected to assess alterations in autophagy using immunofluorescence, immunoblotting and electron microscopy assays. RESULTS: Both in SH-SY5Y cells and in the midbrain of UPS-impaired mouse model of PD, treatment with lactacystin significantly increased the expression levels of LC3-I/II and Beclin 1, and reduced the levels of p-mTOR, mTOR and p62/SQSTM1. Furthermore, lactacystin treatment in UPS-impaired mouse model of PD caused significant loss of TH-positive neurons in the substantia nigra, and dramatically increased the number of autophagosomes in the left TH-positive neurons. CONCLUSION: Inhibition of UPS by lactacystin in dopaminergic neurons activates another protein degradation system, the ALP, which includes both the mTOR signaling pathway and Beclin 1-associated pathway.


Assuntos
Acetilcisteína/análogos & derivados , Autofagia/efeitos dos fármacos , Mesencéfalo/patologia , Doença de Parkinson/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/farmacologia , Ubiquitina/metabolismo , Acetilcisteína/farmacologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1 , Linhagem Celular Tumoral , Humanos , Masculino , Proteínas de Membrana/metabolismo , Mesencéfalo/efeitos dos fármacos , Mesencéfalo/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Doença de Parkinson/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
8.
Biochim Biophys Acta ; 1812(12): 1675-80, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21982945

RESUMO

The JmjC-domain-containing protein Hairless (HR) and the vitamin D receptor (VDR) play a critical role in the maintenance of hair growth. Mutations in HR or VDR cause alopecia in humans and mice. Here we show that HR interacts with VDR and induces VDR relocalization in the nuclei. HR associates and colocalizes with nuclear receptor co-repressor (N-CoR) which is localized to subnuclear structures termed matrix-associated deacetylase (MAD) bodies. It is found that the HR mutants (C622G, N970S, D1012N, V1136D), associated with alopecia universalis congenita (AUC) or atrichia with papular lesions (APL), exhibit an abnormal subcellular distribution in addition to the impaired co-repressor activity with VDR. Studies on deletion mutants of HR indicate that the JmjC domain contributes to the co-repressor activity of HR. Our work provides new clues and evidence for the understanding on the role of HR in hair growth.


Assuntos
Receptores de Calcitriol/metabolismo , Fatores de Transcrição/metabolismo , Substituição de Aminoácidos , Linhagem Celular , Núcleo Celular/metabolismo , Proteínas Correpressoras/química , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Regulação da Expressão Gênica , Genes Reporter , Humanos , Luciferases de Renilla/biossíntese , Luciferases de Renilla/genética , Mutagênese Sítio-Dirigida , Correpressor 1 de Receptor Nuclear/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Transporte Proteico , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Fatores de Transcrição/química , Fatores de Transcrição/genética , Ativação Transcricional
9.
J Cell Physiol ; 227(6): 2645-53, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21938722

RESUMO

Growth associated protein 43 (Gap43) is a neuron-specific phosphoprotein, which plays critical role in axon growth and synapses functions during neurogenesis. Here we identified two transcription start sites (TSSs) of the mouse Gap43 gene designated as a proximal site at +1, and a distal TSS at -414. RT-qPCR data reveal that the transcripts from +1 increase 10-fold on day-1 post-all-trans retinoic acid (RA) treatment, reached a peak value at day-4 and gradually reduced. By contrast, the distal TSS directs a late, remarkably sharp increase of the transcripts from the day-5 on. An intense signal of Gap43 at the neurites and neural network is determined by the efficient transcription of the distal promoter as shown in Northern blot and RT-qPCR assay. In addition, the targeting of p300 in combination with a differential enrichment of Brm to Brg1 change at the distal promoter region of the gene is induced under RA treatment. The over hundreds of GA rich stretches and the GAGAG elements located between the two TSSs may take parts in the differential transcription of the two TSSs of the Gap43. Our findings provide the first evidence on the identification and differential transcription of the two TSSs of the mouse Gap43 gene, and the preferential distribution of their protein products in the specific stages of RA induced P19 differentiation. These data suggest the efficient transcription of the distal promoter of Gap43 is an important mark for the transition of P19 cells from the progenitor stage into neuronal differentiation.


Assuntos
Proteína GAP-43/metabolismo , Neurogênese , Neurônios/metabolismo , Animais , Sequência de Bases , Northern Blotting , Linhagem Celular Tumoral , Montagem e Desmontagem da Cromatina , DNA Helicases/metabolismo , Proteína GAP-43/genética , Camundongos , Dados de Sequência Molecular , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Interferência de RNA , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo , Fatores de Transcrição/metabolismo , Sítio de Iniciação de Transcrição , Transcrição Gênica , Transfecção , Tretinoína/farmacologia , Fatores de Transcrição de p300-CBP/metabolismo
10.
BMC Neurosci ; 13: 6, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22221422

RESUMO

BACKGROUND: Pluripotent cells maintain a unique gene expression pattern and specific chromatin signature. In this study, we explored the effect of the methyltransferase inhibitor adenosine dialdehyde (AdOx) on pluripotency maintenance and gene expression in P19 embryonal carcinoma cells. RESULTS: After AdOx treatment, the pluripotency-related gene network became disordered, and the early developmental genes were released from the repression. Remarkably, AdOx caused contrasting effects on the expression of two key pluripotency genes, nanog and oct3/4, with the reduction of the repressive histone marks H3K27me3, H3K9me3 and H3K9me2 only in the nanog gene. CONCLUSIONS: Key pluripotency genes were controlled by different mechanisms, including the differential enrichment of repressive histone methylation marks. These data provided novel clues regarding the critical role of histone methylation in the maintenance of pluripotency and the determination of cell fate in P19 pluripotent cells.


Assuntos
Adenosina/análogos & derivados , Inibidores Enzimáticos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Adenosina/farmacologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma/patologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Camundongos , Proteína Homeobox Nanog , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fatores de Tempo , Tretinoína/farmacologia
11.
Gland Surg ; 11(1): 226-235, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35242684

RESUMO

BACKGROUND: Due to the lack of high-level data, there is still controversy over the oncological safety of breast conservation in patients with centrally located breast cancer. This study aimed to assess the safety of breast-conserving surgery in patients with centrally located breast cancer based on the data from the Surveillance, Epidemiology, and End Results (SEER) database. METHODS: We collected data for all cases diagnosed with breast cancer who underwent breast-conserving surgery from 2012-2014 in the SEER database. The primary outcome of our study was disease-specific survival (DSS) and overall survival (OS). The PSM was used to eliminate the effects of non-random statistics. Chi-square test, Kaplan-Meier method and Cox proportional hazards regression model on univariate and multivariate analysis were used to analyze the data. RESULTS: Data from 79,214 patients who had undergone breast-conserving surgery were analyzed in this study, including those with breast cancer in the central region (n=3,128) and outside the central region (n=76,086). The DSS of central breast cancer patients and outside the central breast cancer patients was 58.1 months versus 58.0 months (P>0.05), respectively, while the OS of the 2 groups was 58.0 months versus 58.0 months (P>0.05), respectively. CONCLUSIONS: Breast cancer in the central region should not be contraindicated for breast conserving surgery and breast-conserving surgery can benefit a wider range of patients.

12.
Biochim Biophys Acta ; 1789(11-12): 758-62, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19800042

RESUMO

Little is known about the mechanisms underlying heat shock-mediated inhibition of cyclin D1 transcription. Here, we report that NF-kappaB site-mediated cyclin D1 transcription is inhibited by heat shock. The mRNA level of cyclin D1 decreased under heat shock (40-60%). This inhibition of transcription is promoter activity dependent and is mediated by the proximal NF-kappaB site. However, P65 overexpression did not influence the heat-inducible inhibitory pattern and heat shock did not significantly change the binding activity of p65. P53 can inhibit cyclin D1 promoter activity via an NF-kappaB site-dependent manner and its binding activity increased after heat shock. Importantly, p53 overexpression can prevent cyclin D1 promoter activation by p65. Therefore, we can deduce that p53 inhibits promoter activity under heat shock. These results reveal that the mechanism of heat shock-mediated inhibition of cyclin D1 transcription involves an NF-kappaB site. The data presented provide a new insight into the underlying heat shock inhibition of gene transcription.


Assuntos
Ciclina D1/genética , Temperatura Alta , Fator de Transcrição RelA/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Sítios de Ligação/genética , Western Blotting , Linhagem Celular Tumoral , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , Imunoprecipitação da Cromatina , Regulação Neoplásica da Expressão Gênica , Humanos , Regiões Promotoras Genéticas/genética , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição RelA/genética , Transcrição Gênica , Transfecção , Proteína Supressora de Tumor p53/genética
13.
J Cell Biochem ; 110(6): 1457-63, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20506217

RESUMO

Covalent modifications of histone tails have fundamental roles in chromatin structure and function. Tri-methyl modification on lysine 27 of histone H3 (H3K27me3) usually correlates with gene repression that plays important roles in cell lineage commitment and development. Mash1 is a basic helix-loop-helix regulatory protein that plays a critical role in neurogenesis, where it expresses as an early marker. In this study, we have shown a decreased H3K27me3 accompanying with an increased demethylase of H3K27me3 (Jmjd3) at the promoter of Mash1 can elicit a dramatically efficient expression of Mash1 in RA-treated P19 cells. Over-expression of Jmjd3 in P19 cells also significantly enhances the RA-induced expression and promoter activity of Mash1. By contrast, the mRNA expression and promoter activity of Mash1 are significantly reduced, when Jmjd3 siRNA or dominant negative mutant of Jmjd3 is introduced into the P19 cells. Chromatin immunoprecipitation assays show that Jmjd3 is efficiently recruited to a proximal upstream region of Mash1 promoter that is overlapped with the specific binding site of Hes1 in RA-induced cells. Moreover, the association between Jmjd3 and Hes1 is shown in a co-Immunoprecipitation assay. It is thus likely that Jmjd3 is recruited to the Mash1 promoter via Hes1. Our results suggest that the demethylase activity of Jmjd3 and its mediator Hes1 for Mash1 promoter binding are both required for Jmjd3 enhanced efficient expression of Mash1 gene in the early stage of RA-induced neuronal differentiation of P19 cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Histona Desmetilases com o Domínio Jumonji/metabolismo , Tretinoína/farmacologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular , Linhagem Celular Tumoral , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Immunoblotting , Imunoprecipitação , Histona Desmetilases com o Domínio Jumonji/genética , Luciferases/genética , Luciferases/metabolismo , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição HES-1
14.
J Cell Biochem ; 110(1): 162-70, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20213728

RESUMO

CARM1/PRMT4 is a member of the protein arginine methyltransferase (PRMT) family. CARM1 as a transcriptional coactivator plays an active role on mammalian genes. Here, we show that CARM1 can be recruited to the promoter of myogenin gene to enhance its transcriptional activation via PCAF at the early stage of TPA-induced RD cell differentiation. By adding adenosine dialdehyde, AdOx, to inhibit the PRMT in RD cells, the TPA-induced recruiting of p300, PCAF and the Brg1 at the myogenin promoter is abolished and myogenic differentiation is blocked. More specifically, the expression of PCAF and its nucleation are prohibited when CARM1 is knockdown by its specific siRNA. We suggest that the physical interaction of CARM1 and PCAF is likely pivotal for the activation of PCAF in the downstream of CARM1 pathway for inducing myogenin under TPA-induced differentiation. The findings shed lights on novel therapeutic targets in the treatment of rhabdomyosarcoma patients.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Miogenina/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Rabdomiossarcoma/enzimologia , Acetato de Tetradecanoilforbol/farmacologia , Ativação Transcricional/efeitos dos fármacos , Fatores de Transcrição de p300-CBP/metabolismo , Adenosina/análogos & derivados , Adenosina/farmacologia , Diferenciação Celular/genética , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Miogenina/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Proteína-Arginina N-Metiltransferases/genética , Rabdomiossarcoma/genética , Rabdomiossarcoma/patologia , Fatores de Transcrição de p300-CBP/genética
15.
Chin Med Sci J ; 25(2): 71-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20598227

RESUMO

OBJECTIVE: To investigate the regulatory mechanisms of acetylated p53 in the expression of microtubule-associated protein-2 (MAP2) in neuronal differentiation of P19 cells induced by all-trans retinoic acid (RA). METHODS: Neuronal differentiation of P19 cells was initiated with 4-day RA treatment. Immunofluorescence, real-time reverse transcription-polymerase chain reaction (RT-PCR) assay, and map2 promoter driven luciferase assay were performed to detect the expression and relative promoter activity of MAP2 in those RA-treated cells. Real-time PCR-based chromatin immunoprecipitation assay (ChIP) was carried out to reveal the specific recruitment of acetylated p53 onto its binding sites on map2 promoter. RESULTS: The expression of MAP2 was markedly increased in RA-induced P19 cells. The map2 mRNA increased 34-fold after 4 days of RA treatment and 730-fold 2 days after the treatment, compared with the cells without RA treatment (control). p53 was recruited to the promoter of map2 gene in acetylated form and thereby enhanced its promoter activity. p300/CBP associated factor (PCAF) was found induced in RA-treated cells and enriched in the nucleus, which might contribute to the acetylation of p53 in the regulation of map2 gene. CONCLUSIONS: Acetylated p53 may participate in regulating the expression of map2 in RA-induced differentiation of P19 cells. PCAF is possibly involved in this process by mediating the acetylation of p53.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Tretinoína/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Sequência de Bases , Linhagem Celular , Primers do DNA , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Zhonghua Fu Chan Ke Za Zhi ; 45(9): 682-5, 2010 Sep.
Artigo em Zh | MEDLINE | ID: mdl-21092549

RESUMO

OBJECTIVE: To evaluate the effect of exogenous wild PTEN gene stable transfected into human ovarian cancer cell line HO-8910 on phosphatidyl inositol 3-kinase (PI3K)/protein kinase B (Akt) signal pathway and cells proliferation. METHODS: Wild-type PTEN recombinant eukaryotic expression plasmid was constructed and then was transfected into HO-8910 cells by lipofectamine 2000. The expression of PTEN, Akt1, Akt2, PI3K mRNA and protein of PTEN were tested by reverse transcription (RT)-PCR and Western blot. The proliferation of HO-8910 after wild PTEN gene transfected was measured by methyl thiazolyl tetrazolium (MTT). RESULTS: Wild-type PTEN gene was successfully transfected into HO-8910 cells. The results of RT-PCR and western bolt showed that there were the significant expression high level of PTEN mRNA and protein after infected by wild-PTEN plasmid than those in the control [(17,372 ± 23) vs. (39 ± 1) vs. (78 ± 4) copies/ml, P < 0.05]. While the expression of mRNA of Akt1, Akt2 and PI3K were decreased clearly than those in the control [(28 ± 2) vs. (115 ± 5), (7 ± 1) vs. (18 ± 2), (61 ± 2) vs. (84 ± 2) copies/ml, all P < 0.05]. The proliferation rate of HO-8910 cells was obviously slower than those in the control (90 158 ± 47 vs. 148,251 ± 65 vs. 250,115 ± 62, P < 0.05). CONCLUSION: Transfection of PTEN may increase the expression of PTEN and inhibit the proliferation of HO-8910 cells, in which PI3K/Akt signal pathway is inhibit significantly.


Assuntos
Neoplasias Ovarianas/metabolismo , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Southern Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Vetores Genéticos/genética , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/genética , Plasmídeos/genética , Proteínas Proto-Oncogênicas c-akt/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
17.
Brain Behav ; 10(4): e01567, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32154657

RESUMO

OBJECTIVE: To explore the function of miR-30b in pathogenesis of Parkinson's disease (PD) and its underlying molecular mechanism. MATERIALS AND METHODS: We used 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPP(+)) as a tool for constructing the PD cell model, using miR-30b mimics or inhibitors to manipulate miR-30b level for an experimental model of acquisition. The cell viability of SH-SY5Y was detected by CCK, and luciferase was used to screen the binding of target genes. The protein levels of SNCA were measured by Western blot. Then, we investigate the changes in pro- and anti-apoptotic markers with or without miR-30b treatment. RESULTS: There was a significant low expression of MiR-30b in MPP(+)-induced cells. SH-SY5Y cell viability was rescued by MiR-30b overexpression. Luciferase experiments showed that MiR-30b may bind to the 3'-UTR side of SNCA and inhibited its expression. By Western blot, the SNCA level was markedly decreased by miR-30b. miR-30b attenuated the upregulation of Bax and the depletion of Bcl-2 induced by MPP(+).


Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Neurônios Dopaminérgicos/metabolismo , MicroRNAs/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Células HEK293 , Humanos , MicroRNAs/genética , Transtornos Parkinsonianos/genética , Transtornos Parkinsonianos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Regulação para Cima/efeitos dos fármacos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
18.
J Cell Biochem ; 107(2): 264-71, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19308998

RESUMO

Neurogenin1 is an important bHLH protein that plays crucial role in neurogenesis. We first show that the expression of ngn1 increases drastically in RA induced neuronal differentiation. During which, a three successive stages of the epigenetic changes surrounding the ngn1 gene are found correlated with a repression to activation of the gene in P19 cells. Recruiting of a repressive histone code H3K27me3 on the ngn1 gene is the dominant change in first repression stage, which is followed by the binding of the active codes of H3K9ac, H3K14ac, and the H3K4me3 in the second and third stages of RA treatment. Additionally, BRM but not BRG1 is specifically recruited to ngn1 gene at the third stage and is positively involved in the RA induced ngn1 expression. We propose that histone modifiers and chromatin remodelers are pivotal in the activation of the ngn1 gene in RA induced differentiation of P19 cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular/genética , Montagem e Desmontagem da Cromatina/genética , Regulação da Expressão Gênica/genética , Histonas/metabolismo , Proteínas do Tecido Nervoso/genética , Neurônios/citologia , Acetilação , Animais , Antineoplásicos/farmacologia , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Proteínas Cromossômicas não Histona , Imunofluorescência , Histonas/genética , Imunoprecipitação , Metilação , Camundongos , Neurogênese/genética , Neurônios/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição , Tretinoína/farmacologia
19.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 31(6): 756-9, 2009 Dec.
Artigo em Zh | MEDLINE | ID: mdl-20078948

RESUMO

OBJECTIVE: To explore the effects of PIH1D1 on its binding protein SNF5, a core subunit of the SWI/SNF chromatin remodeling complex. METHOD: The degradation pathway of SNF5 was identified with protein synthesis inhibitor cycloheximide (CHX) and a potent proteasome inhibitor MG132, and then the PIH1D1 eukaryotic expression plasmid was transfected to explore its effect on the stability of SNF5. RESULTS: HEK293T cells were effectively treated with CHX (optimal concentration: 400 microg/ml) and MG132 (optimal concentration: 20 mmol/L). The degradation of SNF5 was mediated by the proteasome pathway. PIH1D1 regulated the protein level of SNF5 by attenuating its proteasome degradation. CONCLUSION: PIH1D1 may stabilize SNF5 by attenuating its proteasome degradation pathway.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Vetores Genéticos , Células HEK293 , Humanos , Plasmídeos/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína SMARCB1 , Transfecção
20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 31(6): 692-5, 2009 Dec.
Artigo em Zh | MEDLINE | ID: mdl-20078936

RESUMO

OBJECTIVE: To construct the eukaryotic expression plasmid of mouse histone lysine methyltransferase Setd7 and detect its effect on neuron development. METHODS: The clone of mouse Setd7 was obtained and inserted into the eukaryotic expression vector pCMV-3tag-6-Flag. The plasmid was transfected into HEK 293T and identified by Western blot. Real-time PCR was used to detect the effect of Setd7 on the neuron differentiation marker gene Ngn 1 mRNA expression. Dual luciferase reporter system was used to detect the effect of Setd7 on Ngn 1 mRNA expression. Real-time PCR was used to detect the effect of Setd 7 siRNA plasmid on Ngn 1 mRNA expression. RESULTS: An eukaryotic expression plasmid of Setd 7 was successfully constructed. Setd7 induced Ngn 1 mRNA expression and increased Ngn 1 promoter activity. Also, the knockdown of Setd 7 inhibited Ngn 1 mRNA expression. CONCLUSION: Histone lysine methyltransferase Setd7 can enhance neuron differentiation marker gene Ngn 1 transcription.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Histona-Lisina N-Metiltransferase/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas Metiltransferases/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Regulação da Expressão Gênica , Vetores Genéticos , Células HEK293 , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas Metiltransferases/metabolismo , RNA Mensageiro/genética , Transfecção
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa