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1.
Cell Mol Life Sci ; 76(15): 3005-3018, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31006037

RESUMO

The accumulation of intracellular ß-amyloid peptide (Aß) is important pathological characteristic of Alzheimer's disease (AD). However, the exact underlying molecular mechanism remains to be elucidated. Here, we reported that Nuclear Paraspeckle Assembly Transcript 1 (NEAT1), a long n on-coding RNA, exhibits repressed expression in the early stage of AD and its down-regulation declines neuroglial cell mediating Aß clearance via inhibiting expression of endocytosis-related genes. We find that NEAT1 is associated with P300/CBP complex and its inhibition affects H3K27 acetylation (H3K27Ac) and H3K27 crotonylation (H3K27Cro) located nearby to the transcription start site of many genes, including endocytosis-related genes. Interestingly, NEAT1 inhibition down-regulates H3K27Ac but up-regulates H3K27Cro through repression of acetyl-CoA generation. NEAT1 also mediates the binding between STAT3 and H3K27Ac but not H3K27Cro. Therefore, the decrease of H3K27Ac and/or the increase of H3K27Cro declines expression of multiple related genes. Collectively, this study first reveals the different roles of H3K27Ac and H3K27Cro in regulation of gene expression and provides the insight of the epigenetic regulatory mechanism of NEAT1 in gene expression and AD pathology.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Fragmentos de Peptídeos/metabolismo , RNA Longo não Codificante/metabolismo , Acetilcoenzima A/metabolismo , Acetilação/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/farmacologia , Animais , Caveolina 2/antagonistas & inibidores , Caveolina 2/genética , Caveolina 2/metabolismo , Modelos Animais de Doenças , Epigênese Genética , Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Camundongos , Camundongos Transgênicos , Neuroglia/citologia , Neuroglia/metabolismo , Fragmentos de Peptídeos/farmacologia , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/antagonistas & inibidores , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Crescimento Transformador beta2/antagonistas & inibidores , Fator de Crescimento Transformador beta2/genética , Fator de Crescimento Transformador beta2/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo
2.
Int J Cancer ; 143(11): 2919-2931, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29978477

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive gastrointestinal tumors, with an overall 5-year survival rate less than 8%. The dismal prognosis is mainly due to aggressive potential for metastasis. Hence, there is an urgent need for a better understanding of the molecular mechanisms underlying pancreatic cancer invasion and metastasis to improve the unfavorable overall survival (OS) of PDAC patients. In this study, we identified microRNA-29a (miR-29a) as an important tumor suppressor, which was downregulated in PDAC tissues. Moreover, miR-29a counteracted MUC16-mediated migration and invasion. In the pancreatic cancer cells, MUC16 upregulated c-Myc expression, which enhanced c-Myc binding to E-box in the miR-29a promoter and inhibited miR-29a transcription. Thus, miR-29a was negatively correlated with both MUC16 expression and serum CA125 levels. Furthermore, caveolin 2 (CAV2) was demonstrated to be the target of miR-29a by bioinformatics and luciferase reporter assays, and high CAV2 expression was responsible for a poor prognosis, especially in the subgroup with normal CA125 levels. Thus, the present study explains why high levels of serum CA125 are correlated with PDAC metastasis, highlighting the predictive value of this marker in PDAC patients.


Assuntos
Antígeno Ca-125/sangue , Caveolina 2/genética , Proteínas de Membrana/sangue , MicroRNAs/genética , Metástase Neoplásica/genética , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/genética , Genes Supressores de Tumor/fisiologia , Humanos , Metástase Neoplásica/patologia , Neoplasias Pancreáticas/patologia , Prognóstico
3.
Nat Commun ; 9(1): 2727, 2018 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-30006525

RESUMO

Prefrontal cortical areas mediate flexible adaptive control of behavior, but the specific contributions of individual areas and the circuit mechanisms through which they interact to modulate learning have remained poorly understood. Using viral tracing and pharmacogenetic techniques, we show that prelimbic (PreL) and infralimbic cortex (IL) exhibit reciprocal PreL↔IL layer 5/6 connectivity. In set-shifting tasks and in fear/extinction learning, activity in PreL is required during new learning to apply previously learned associations, whereas activity in IL is required to learn associations alternative to previous ones. IL→PreL connectivity is specifically required during IL-dependent learning, whereas reciprocal PreL↔IL connectivity is required during a time window of 12-14 h after association learning, to set up the role of IL in subsequent learning. Our results define specific and opposing roles of PreL and IL to together flexibly support new learning, and provide circuit evidence that IL-mediated learning of alternative associations depends on direct reciprocal PreL↔IL connectivity.


Assuntos
Aprendizagem por Associação/fisiologia , Extinção Psicológica/fisiologia , Medo/fisiologia , Rede Nervosa/metabolismo , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Animais , Aprendizagem por Associação/efeitos dos fármacos , Caveolina 2/genética , Caveolina 2/metabolismo , Clozapina/análogos & derivados , Clozapina/farmacologia , Venenos de Cnidários/farmacologia , Condicionamento Clássico/efeitos dos fármacos , Condicionamento Clássico/fisiologia , Conectoma , Eletrodos Implantados , Extinção Psicológica/efeitos dos fármacos , Medo/efeitos dos fármacos , Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Rede Nervosa/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurotoxinas/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Técnicas Estereotáxicas
4.
Biochim Biophys Acta Mol Basis Dis ; 1864(6 Pt A): 2169-2182, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29604334

RESUMO

Insulin resistance, defined as attenuated sensitivity responding to insulin, impairs insulin action. Direct causes and molecular mechanisms of insulin resistance have thus far remained elusive. Here we show that alternative translation initiation (ATI) of Caveolin-2 (Cav-2) regulates insulin sensitivity. Cav-2ß isoform yielded by ATI desensitizes insulin receptor (IR) via dephosphorylation by protein-tyrosine phosphatase 1B (PTP1B), and subsequent endocytosis and lysosomal degradation of IR, causing insulin resistance. Blockage of Cav-2 ATI protects against insulin resistance by preventing Cav-2ß-PTP1B-directed IR desensitization, thereby normalizing insulin sensitivity and glucose uptake. Our findings show that Cav-2ß is a negative regulator of IR signaling, and identify a mechanism causing insulin resistance through control of insulin sensitivity via Cav-2 ATI.


Assuntos
Antígenos CD/metabolismo , Caveolina 2/metabolismo , Resistência à Insulina/genética , Iniciação Traducional da Cadeia Peptídica/genética , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Receptor de Insulina/metabolismo , Células 3T3 , Animais , Antígenos CD/genética , Caveolina 2/genética , Códon de Iniciação/genética , Endocitose , Células HEK293 , Humanos , Lisossomos/metabolismo , Camundongos , Mutagênese Sítio-Dirigida , Iniciação Traducional da Cadeia Peptídica/efeitos dos fármacos , Fosforilação , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/genética , Proteólise , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptor de Insulina/genética
5.
J Cell Biochem ; 119(2): 2168-2178, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28857238

RESUMO

Most studies have revealed the effects of caveolins in cancer inhibition. However, due to a lack of reports about their new transcripts, their presence and their effects on different cancers are unclear. This study was conducted to evaluate the cavolin-2 (cav-2) transcripts expression changes in tumoral and corresponding tissues and in contralateral breast, to investigate their variation associated with the variation of caveolin-1 (cav-1) expression in breast cancer. There were 40 breast-derived tumoral, corresponding, and contralateral tissues obtained from the patients with breast cancer. The RNA and proteins were extracted from these samples. So, cav-1 and cav-2 transcripts' variation were assessed in whole tumoral, corresponding, and contralateral breast. Also, their expression modifications were evaluated via the Western blotting technique. The results derived from this study verified the presence of transcript III of cav-2 for the first time, which was reported only in the gene bank, but we could not detect and validate any protein associated with these transcripts. Also, the decreasing trend of cav-1 and the cav-2 (transcripts I and II) were observed in tumoral tissues compared to unaffected tissues especially in stages I and II. It seems that the descending expression levels of cav-1 and cav-2 (transcript I, II) besides the lasting expression of cav-2 (transcript III) are associated with the incidence and promotion of breast cancer, especially in the initial stages of breast cancer. So, this may show a potential in determining the patients who can undergo the prophylactic mastectomy. Moreover, the results of the study demonstrated that transcript III may be a candidate as a non-coding RNA.


Assuntos
Neoplasias da Mama/patologia , Caveolina 1/genética , Caveolina 2/genética , Perfilação da Expressão Gênica/métodos , RNA Mensageiro/genética , Análise de Sequência de RNA/métodos , Adulto , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Caveolina 1/metabolismo , Caveolina 2/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Variação Genética , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias
6.
Ophthalmic Genet ; 39(2): 194-199, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29111846

RESUMO

Large-scale genome-wide association studies have identified several susceptibility variants associated with the risk of primary open-angle glaucoma (POAG), among which rs4236601 (CAV1/CAV2) at chromosome 7q31 and rs2157719 at chromosome 9p21 (CDKN2B-AS1). The purpose of this study was to investigate whether these variants contribute to the incidence of POAG in a sample of the Brazilian Southeastern population and to determine the best-fitted genetic model for these single nucleotide polymorphisms (SNPs). A case-control study with 557 individuals, 310 with POAG, and 247 controls was conducted through PCR and direct sequencing. We observed a significant effect of the heterozygous genotype (G/A) of rs2157719 that occurred more frequently in the control group (p = 0.0004; OR: 0.517, CI 95%: 0.357-0.745). Allele frequencies also differed between cases and controls (p = 0.006; OR: 0.694, CI 95%: 0.522-0.922) with the best-fitted genetic model for rs2157719 being the codominant model. No differences were observed for genotype and allele distributions in relation to rs4236601 in the CAV1/CAV2 region. The association of rs2157719 (CDKN2B-AS1) with the POAG phenotype corroborates previously published results, reinforcing the importance of this variant in POAG etiology.


Assuntos
Caveolina 1/genética , Caveolina 2/genética , Glaucoma de Ângulo Aberto/genética , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Glaucoma de Ângulo Aberto/diagnóstico , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade
7.
Circ Cardiovasc Genet ; 10(4)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28794112

RESUMO

BACKGROUND: The P wave on an ECG is a measure of atrial electric function, and its characteristics may serve as predictors for atrial arrhythmias. Increased mean P-wave duration and P-wave terminal force traditionally have been used as markers for left atrial enlargement, and both have been associated with increased risk of atrial fibrillation. Here, we explore the genetic basis of P-wave morphology through meta-analysis of genome-wide association study results for P-wave duration and P-wave terminal force from 12 cohort studies. METHODS AND RESULTS: We included 44 456 individuals, of which 6778 (16%) were of African ancestry. Genotyping, imputation, and genome-wide association study were performed at each study site. Summary-level results were meta-analyzed centrally using inverse-variance weighting. In meta-analyses of P-wave duration, we identified 6 significant (P<5×10-8) novel loci and replicated a prior association with SCN10A. We identified 3 loci at SCN5A, TBX5, and CAV1/CAV2 that were jointly associated with the PR interval, PR segment, and P-wave duration. We identified 6 novel loci in meta-analysis of P-wave terminal force. Four of the identified genetic loci were significantly associated with gene expression in 329 left atrial samples. Finally, we observed that some of the loci associated with the P wave were linked to overall atrial conduction, whereas others identified distinct phases of atrial conduction. CONCLUSIONS: We have identified 6 novel genetic loci associated with P-wave duration and 6 novel loci associated with P-wave terminal force. Future studies of these loci may aid in identifying new targets for drugs that may modify atrial conduction or treat atrial arrhythmias.


Assuntos
Eletrocardiografia , Loci Gênicos , Estudo de Associação Genômica Ampla , Arritmias Cardíacas/genética , Arritmias Cardíacas/fisiopatologia , Caveolina 1/genética , Caveolina 2/genética , Genótipo , Átrios do Coração/metabolismo , Humanos , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Canal de Sódio Disparado por Voltagem NAV1.8/genética , Proteínas com Domínio T/genética
8.
Sci Rep ; 7(1): 5377, 2017 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-28710481

RESUMO

Mutations in the Leucine-rich repeat kinase 2 gene (LRRK2) are associated with familial Parkinson's disease (PD). LRRK2 protein contains several functional domains, including protein-protein interaction domains at its N- and C-termini. In this study, we analyzed the functional features attributed to LRRK2 by its N- and C-terminal domains. We combined TIRF microscopy and synaptopHluorin assay to visualize synaptic vesicle trafficking. We found that N- and C-terminal domains have opposite impact on synaptic vesicle dynamics. Biochemical analysis demonstrated that different proteins are bound at the two extremities, namely ß3-Cav2.1 at N-terminus part and ß-Actin and Synapsin I at C-terminus domain. A sequence variant (G2385R) harboured within the C-terminal WD40 domain increases the risk for PD. Complementary biochemical and imaging approaches revealed that the G2385R variant alters strength and quality of LRRK2 interactions and increases fusion of synaptic vesicles. Our data suggest that the G2385R variant behaves like a loss-of-function mutation that mimics activity-driven events. Impaired scaffolding capabilities of mutant LRRK2 resulting in perturbed vesicular trafficking may arise as a common pathophysiological denominator through which different LRRK2 pathological mutations cause disease.


Assuntos
Caveolina 2/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Neurônios/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Vesículas Sinápticas/metabolismo , Actinas/genética , Actinas/metabolismo , Animais , Transporte Biológico , Caveolina 2/genética , Linhagem Celular , Embrião de Mamíferos , Expressão Gênica , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/química , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Fusão de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Neurônios/citologia , Cultura Primária de Células , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Transdução de Sinais , Sinapsinas/genética , Sinapsinas/metabolismo
9.
Am J Clin Nutr ; 106(1): 263-275, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28592605

RESUMO

Background: Gene-diet interactions have been reported to contribute to the development of type 2 diabetes (T2D). However, to our knowledge, few examples have been consistently replicated to date.Objective: We aimed to identify existing evidence for gene-macronutrient interactions and T2D and to examine the reported interactions in a large-scale study.Design: We systematically reviewed studies reporting gene-macronutrient interactions and T2D. We searched the MEDLINE, Human Genome Epidemiology Network, and WHO International Clinical Trials Registry Platform electronic databases to identify studies published up to October 2015. Eligibility criteria included assessment of macronutrient quantity (e.g., total carbohydrate) or indicators of quality (e.g., dietary fiber) by use of self-report or objective biomarkers of intake. Interactions identified in the review were subsequently examined in the EPIC (European Prospective Investigation into Cancer)-InterAct case-cohort study (n = 21,148, with 9403 T2D cases; 8 European countries). Prentice-weighted Cox regression was used to estimate country-specific HRs, 95% CIs, and P-interaction values, which were then pooled by random-effects meta-analysis. A primary model was fitted by using the same covariates as reported in the published studies, and a second model adjusted for additional covariates and estimated the effects of isocaloric macronutrient substitution.Results: Thirteen observational studies met the eligibility criteria (n < 1700 cases). Eight unique interactions were reported to be significant between macronutrients [carbohydrate, fat, saturated fat, dietary fiber, and glycemic load derived from self-report of dietary intake and circulating n-3 (ω-3) polyunsaturated fatty acids] and genetic variants in or near transcription factor 7-like 2 (TCF7L2), gastric inhibitory polypeptide receptor (GIPR), caveolin 2 (CAV2), and peptidase D (PEPD) (P-interaction < 0.05). We found no evidence of interaction when we tried to replicate previously reported interactions. In addition, no interactions were detected in models with additional covariates.Conclusions: Eight gene-macronutrient interactions were identified for the risk of T2D from the literature. These interactions were not replicated in the EPIC-InterAct study, which mirrored the analyses undertaken in the original reports. Our findings highlight the importance of independent replication of reported interactions.


Assuntos
Diabetes Mellitus/etiologia , Dieta , Carboidratos da Dieta/farmacologia , Gorduras na Dieta/farmacologia , Fibras na Dieta/farmacologia , Comportamento Alimentar , Interação Gene-Ambiente , Estudos de Casos e Controles , Caveolina 2/genética , Diabetes Mellitus/genética , Dipeptidases/genética , Ingestão de Energia , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Receptores dos Hormônios Gastrointestinais/genética , Fatores de Risco , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética
10.
Int J Mol Sci ; 18(4)2017 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-28338624

RESUMO

Membrane microdomains or "lipid rafts" have emerged as essential functional modules of the cell, critical for the regulation of growth factor receptor-mediated responses. Herein we describe the dichotomy between caveolin-1 and caveolin-2, structural and regulatory components of microdomains, in modulating proliferation and differentiation. Caveolin-2 potentiates while caveolin-1 inhibits nerve growth factor (NGF) signaling and subsequent cell differentiation. Caveolin-2 does not appear to impair NGF receptor trafficking but elicits prolonged and stronger activation of MAPK (mitogen-activated protein kinase), Rsk2 (ribosomal protein S6 kinase 2), and CREB (cAMP response element binding protein). In contrast, caveolin-1 does not alter initiation of the NGF signaling pathway activation; rather, it acts, at least in part, by sequestering the cognate receptors, TrkA and p75NTR, at the plasma membrane, together with the phosphorylated form of the downstream effector Rsk2, which ultimately prevents CREB phosphorylation. The non-phosphorylatable caveolin-1 serine 80 mutant (S80V), no longer inhibits TrkA trafficking or subsequent CREB phosphorylation. MC192, a monoclonal antibody towards p75NTR that does not block NGF binding, prevents exit of both NGF receptors (TrkA and p75NTR) from lipid rafts. The results presented herein underline the role of caveolin and receptor signaling complex interplay in the context of neuronal development and tumorigenesis.


Assuntos
Caveolina 1/metabolismo , Núcleo Celular/metabolismo , Microdomínios da Membrana/metabolismo , Fator de Crescimento Neural/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Anticorpos Monoclonais/imunologia , Proteína de Ligação a CREB/metabolismo , Caveolina 1/antagonistas & inibidores , Caveolina 1/genética , Caveolina 2/antagonistas & inibidores , Caveolina 2/genética , Caveolina 2/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Camundongos , Células PC12 , Fosforilação/efeitos dos fármacos , Ligação Proteica , Transporte Proteico/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Receptor de Fator de Crescimento Neural/metabolismo , Receptor trkA/química , Receptor trkA/imunologia , Receptor trkA/metabolismo , Receptores de Fator de Crescimento Neural/química , Receptores de Fator de Crescimento Neural/imunologia , Receptores de Fator de Crescimento Neural/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo
11.
Biochim Biophys Acta ; 1863(11): 2681-2689, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27552914

RESUMO

Association of Caveolin-2 in the inner nuclear membrane specifically with A-type lamin is crucial for the maintenance of its Tyr-19 phosphorylation to promote insulin-response epigenetic activation at the nuclear periphery. Here, we identify that pY19-Caveolin-2 in the inner nuclear membrane exists as homo-oligomeric forms and the A-type lamin is required for sustenance of its oligomeric status. Oligomerization-defective and hence pY19-dephosphorylated monomeric Caveolin-2 in the inner nuclear membrane is unable to carry out Caveolin-2-mediated epigenetic activation of Egr-1 and JunB genes and transactivation of Elk-1 and STAT3 in response to insulin. The homo-oligomeric pY19-Caveolin-2 localizes in and recruits epigenetic modifiers to the A-type lamin-enriched inner nuclear membrane microdomain for the epigenetic activation. Our data show that A-type lamin-dependent Caveolin-2 homo-oligomerization in the inner nuclear membrane microdomain is a precondition for pY19-Caveolin-2-mediated insulin-response epigenetic activation at the nuclear periphery.


Assuntos
Caveolina 2/metabolismo , Epigênese Genética/efeitos dos fármacos , Insulina/farmacologia , Lamina Tipo A/metabolismo , Membrana Nuclear/efeitos dos fármacos , Caveolina 2/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Células HEK293 , Histonas/metabolismo , Humanos , Lamina Tipo A/genética , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/metabolismo , Membrana Nuclear/metabolismo , Fosforilação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico , Interferência de RNA , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional , Transfecção , Tirosina , Proteínas Elk-1 do Domínio ets/genética , Proteínas Elk-1 do Domínio ets/metabolismo
12.
Sci Rep ; 6: 27837, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27297022

RESUMO

A single-nucleotide polymorphism (SNP) rs4236601 at the CAV1/CAV2 locus is associated with primary open-angle glaucoma (POAG). Rs4236601 is common in Caucasians but rare in East Asians. Here we conducted a haplotype-tagging SNP analysis followed by replication in a total of 848 POAG cases and 1574 controls drawn from 3 cities in China and 1 city in Japan. Two SNPs, rs4236601 (odds ratio [OR] = 6.25; P = 0.0086) and a tagging-SNP rs3801994 (OR = 1.32; P = 0.042), were associated with POAG in the Hong Kong Chinese cohort after age and gender adjustments. Rs4236601 was associated with POAG also in Shantou (OR = 6.09; P = 0.0037) and Beijing (OR = 3.92; P = 0.030) cohorts after age and gender adjustment, with a pooled-OR of 5.26 (P = 9.0 × 10(-6)) in Chinese; but it is non-polymorphic in the Osaka cohort. SNP rs3801994 showed a similar trend of effect in the Shantou and Beijing cohorts, with a pooled-OR of 1.23 (P = 0.022) and 1.20 (P = 0.063) in Chinese, prior to and after age and gender adjustment, respectively; but it showed a reverse effect in the Osaka cohort (OR = 0.58; P = 0.033) after the adjustments. We have thus confirmed the association of rs4236601 with POAG in different Chinese cohorts. Also, we found a common SNP rs3801994 of diverse associations with POAG between Chinese and Japanese.


Assuntos
Caveolina 1/genética , Caveolina 2/genética , Grupos Étnicos , Genótipo , Glaucoma de Ângulo Aberto/genética , Idoso , Idoso de 80 Anos ou mais , Grupo com Ancestrais do Continente Asiático , China , Estudos de Coortes , Grupo com Ancestrais do Continente Europeu , Feminino , Estudos de Associação Genética , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
13.
Am J Physiol Heart Circ Physiol ; 311(2): H415-25, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27317631

RESUMO

Caveolin-2 (Cav2) is a major protein component of caveolae in membranes of vascular smooth muscle and endothelium, yet its absence alters the ultrastructure of skeletal muscle fibers. To gain insight into Cav2 function in skeletal muscle, we tested the hypothesis that genetic deletion of Cav2 would alter microvascular reactivity and depress contractile function of skeletal muscle in vivo. In the left gluteus maximus muscle (GM) of anesthetized Cav2(-/-) and wild-type (WT) male mice (age, 6 mo), microvascular responses to physiological agonists and to GM contractions were studied at 34°C. For feed arteries (FA), first- (1A), second- (2A) and third-order (3A) arterioles, respective mean diameters at rest (45, 35, 25, 12 µm) and during maximal dilation (65, 55, 45, 30 µm) were similar between groups. Cumulative dilations to ACh (10(-9) to 10(-5) M) and constrictions to norepinephrine (10(-9) to 10(-5) M) were also similar between groups, as were steady-state dilations during rhythmic twitch contractions (2 and 4 Hz; 30 s). For single tetanic contractions (100 Hz; 100, 250, and 500 ms), rapid onset vasodilation (ROV) increased with contraction duration throughout networks in GM of both groups but was reduced by nearly half in Cav2(-/-) mice compared with WT mice (P < 0.05). Nevertheless, maximal force during tetanic contraction was ∼40% greater in GM of Cav2(-/-) vs. WT mice (152 ± 14 vs. 110 ± 3 mN per square millimeter, respectively; P < 0.05). Thus, while structural and functional properties of resistance networks are well maintained in the GM of Cav2(-/-) mice, diminished ROV with greater force production reveals novel physiological roles for Cav2 in skeletal muscle.


Assuntos
Arteríolas/fisiopatologia , Caveolina 2/genética , Contração Muscular , Músculo Esquelético/irrigação sanguínea , Músculo Liso Vascular/fisiopatologia , Vasodilatação/genética , Acetilcolina/farmacologia , Animais , Artérias/efeitos dos fármacos , Artérias/fisiopatologia , Arteríolas/efeitos dos fármacos , Nádegas , Microscopia Intravital , Masculino , Camundongos , Camundongos Knockout , Microvasos/efeitos dos fármacos , Microvasos/fisiopatologia , Músculo Liso Vascular/efeitos dos fármacos , Norepinefrina/farmacologia , Resistência Vascular , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
14.
Eur J Cell Biol ; 95(8): 252-64, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27168348

RESUMO

Caveolins (Cav-1, -2 and -3) and Cavins (Cavin-1, -2, -3 and -4) are two protein families controlling the biogenesis and function of caveolae, plasma membrane omega-like invaginations representing the primary site of important cellular processes like endocytosis, cholesterol homeostasis and signal transduction. Caveolae are especially abundant in fat tissue, playing a consistent role in a number of processes, such as the insulin-dependent glucose uptake and transmembrane transport of lipids underlying differentiation, maintenance and adaptive hypertrophy of adipocytes. Based on this premise, in this work we have investigated the expression of caveolar protein components in liposarcoma (LPS), an adipocytic soft tissue sarcoma affecting adults categorized in well-differentiated, dedifferentiated, myxoid and pleomorphic histotypes. By performing an extensive microarray data analysis followed by immunohistochemistry on human LPS tumors, we demonstrated that Cav-1, Cav-2 and Cavin-1 always cluster in all the histotypes, reaching the highest expression in well-differentiated LPS, the least aggressive of the malignant forms composed by tumor cells with a morphology resembling mature adipocytes. In vitro experiments carried out using two human LPS cell lines showed that the expression levels of Cav-1, Cav-2 and Cavin-1 proteins were faintly detectable during cell growth, becoming consistently increased during the accumulation of intracellular lipid droplets characterizing the adipogenic differentiation. Moreover, in differentiated LPS cells the three proteins were also found to co-localize and form molecular aggregates at the plasma membrane, as shown via immunofluorescence and immunoprecipitation analysis. Overall, these data indicate that Cav-1, Cav-2 and Cavin-1 may be considered as reliable markers for identification of LPS tumors characterized by consistent adipogenic differentiation.


Assuntos
Adipogenia , Caveolina 1/metabolismo , Caveolina 2/metabolismo , Lipossarcoma/genética , Caveolina 1/genética , Caveolina 2/genética , Diferenciação Celular , Linhagem Celular Tumoral , Humanos
15.
Virology ; 492: 66-72, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26901486

RESUMO

BK polyomavirus (BKPyV) is a human pathogen that causes polyomavirus-associated nephropathy and hemorrhagic cystitis in transplant patients. Gangliosides and caveolin proteins have previously been reported to be required for BKPyV infection in animal cell models. Recent studies from our lab and others, however, have indicated that the identity of the cells used for infection studies can greatly influence the behavior of the virus. We therefore wished to re-examine BKPyV entry in a physiologically relevant primary cell culture model, human renal proximal tubule epithelial cells. Using siRNA knockdowns, we interfered with expression of UDP-glucose ceramide glucosyltransferase (UGCG), and the endocytic vesicle coat proteins caveolin 1, caveolin 2, and clathrin heavy chain. The results demonstrate that while BKPyV does require gangliosides for efficient infection, it can enter its natural host cells via a caveolin- and clathrin-independent pathway. The results emphasize the importance of studying viruses in a relevant cell culture model.


Assuntos
Vírus BK/efeitos dos fármacos , Caveolina 1/genética , Caveolina 2/genética , Cadeias Pesadas de Clatrina/genética , Células Epiteliais/efeitos dos fármacos , Interações Hospedeiro-Patógeno , Vírus BK/genética , Vírus BK/metabolismo , Caveolina 1/antagonistas & inibidores , Caveolina 1/metabolismo , Caveolina 2/antagonistas & inibidores , Caveolina 2/metabolismo , Linhagem Celular , Cadeias Pesadas de Clatrina/antagonistas & inibidores , Cadeias Pesadas de Clatrina/metabolismo , Células Epiteliais/virologia , Gangliosídeo G(M1)/farmacologia , Gangliosídeos/farmacologia , Regulação da Expressão Gênica , Humanos , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/virologia , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas de Transporte de Monossacarídeos/antagonistas & inibidores , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Cultura Primária de Células , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Internalização do Vírus/efeitos dos fármacos
16.
Atherosclerosis ; 246: 148-156, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26775120

RESUMO

BACKGROUND: The CAV1 gene encodes caveolin-1 expressed in cell types relevant to atherosclerosis. Cav-1-null mice showed a protective effect on atherosclerosis under the ApoE(-/-) background. However, it is unknown whether CAV1 is linked to CAD and MI in humans. In this study we analyzed a tagSNP for CAV1 in intron 2, rs3807989, for potential association with CAD. METHODS AND RESULTS: We performed case-control association studies in three independent Chinese Han populations from GeneID, including 1249 CAD cases and 841 controls in Population I, 1260 cases and 833 controls in Population II and 790 cases and 1212 controls in Population III (a total of 3299 cases and 2886 controls). We identified significant association between rs3807989 and CAD in three independent populations and in the combined population (Padj = 2.18 × 10(-5), OR = 1.19 for minor allele A). We also detected significant association between rs3807989 and MI (Padj = 5.43 × 10(-5), OR = 1.23 for allele A). Allele A of SNP rs3807989 was also associated with a decreased level of LDL cholesterol. Although rs3807989 is a tagSNP for both CAV1 and nearby CAV2, allele A of SNP rs3807989 was associated with an increased expression level of CAV1 (both mRNA and protein), but not CAV2. CONCLUSIONS: The data in this study demonstrated that rs3807989 at the CAV1/CAV2 locus was associated with significant risk of CAD and MI by increasing expression of CAV1 (but not CAV2). Thus, CAV1 becomes a strong candidate susceptibility gene for CAD/MI in humans.


Assuntos
Caveolina 1/genética , Doença da Artéria Coronariana/genética , Infarto do Miocárdio/genética , Polimorfismo de Nucleotídeo Único , Idoso , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , Caveolina 1/sangue , Caveolina 2/genética , China/epidemiologia , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/etnologia , Bases de Dados Genéticas , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etnologia , Fenótipo , Fatores de Risco , Regulação para Cima
17.
Nat Neurosci ; 19(2): 233-42, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26691831

RESUMO

GABAB receptors, the most abundant inhibitory G protein-coupled receptors in the mammalian brain, display pronounced diversity in functional properties, cellular signaling and subcellular distribution. We used high-resolution functional proteomics to identify the building blocks of these receptors in the rodent brain. Our analyses revealed that native GABAB receptors are macromolecular complexes with defined architecture, but marked diversity in subunit composition: the receptor core is assembled from GABAB1a/b, GABAB2, four KCTD proteins and a distinct set of G-protein subunits, whereas the receptor's periphery is mostly formed by transmembrane proteins of different classes. In particular, the periphery-forming constituents include signaling effectors, such as Cav2 and HCN channels, and the proteins AJAP1 and amyloid-ß A4, both of which tightly associate with the sushi domains of GABAB1a. Our results unravel the molecular diversity of GABAB receptors and their postnatal assembly dynamics and provide a roadmap for studying the cellular signaling of this inhibitory neurotransmitter receptor.


Assuntos
Proteômica/métodos , Receptores de GABA-B/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Caveolina 2/genética , Membrana Celular/genética , Membrana Celular/metabolismo , Epitopos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Ratos , Ratos Wistar , Receptores Acoplados a Proteínas-G , Receptores de GABA-B/metabolismo , Transdução de Sinais/fisiologia
18.
J Cell Physiol ; 231(6): 1219-25, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26480297

RESUMO

The sex hormone 17ß-estradiol (E2) exerts pleiotropic effects by binding to the ligand-activated transcription factor estrogen receptor α (ERα). The E2:ERα complex regulates several physiological processes, including cell survival and proliferation, through transcriptional effects (i.e., estrogen responsive element [ERE]-based gene transcription) and non-transcriptional membrane-initiated effects (i.e., the activation of extra-nuclear signaling cascades), which derive from the activation of the pool of ERα that is localized to plasma membrane caveolae. Caveolae are ω-shaped membrane sub-domains that are composed of scaffold proteins named caveolins (i.e., caveolin-1, caveolin-2, and caveolin-3). Although caveolin-3 is exclusively expressed in muscles, caveolin-1 and caveolin-2 are co-expressed in all human tissues. From a functional point of view, caveolin-2 can operate both dependently on and independently of caveolin-1, which is the main coat component of caveolae. Interestingly, while a functional interplay between caveolin-1 and ERα has been reported in the control of E2-induced physiological effects, the role of caveolin-2 in E2:ERα signaling within the cell remains poorly understood. This study shows that siRNA-mediated caveolin-2 depletion in breast ductal carcinoma cells (MCF-7) reduces E2-induced ERα phosphorylation at serine residue 118 (S118), controls intracellular receptor levels, precludes ERα-mediated extra-nuclear activation of signaling pathways, reduces ERα transcriptional activity, and prevents cellular proliferation. Meanwhile, the impact of caveolin-1 depletion on ERα signaling in MCF-7 cells is shown to be similar to that elicited by siRNA-mediated caveolin-2 depletion. Altogether, these data demonstrate that caveolin-2 expression is necessary for the control of E2-dependent cellular proliferation.


Assuntos
Neoplasias da Mama/metabolismo , Caveolina 2/metabolismo , Proliferação de Células/efeitos dos fármacos , Estradiol/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Caveolina 1/genética , Caveolina 1/metabolismo , Caveolina 2/genética , Receptor alfa de Estrogênio/agonistas , Receptor alfa de Estrogênio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Fosforilação , Proteólise , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transcrição Genética , Transfecção
19.
Immunobiology ; 220(11): 1266-74, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26215374

RESUMO

Caveolins are specific proteins involved in regulation of signal transduction to intracellular space. Still, their contribution to immune functions has not been completely clarified. Thus, we decided to characterize the expression of caveolins in bone marrow-derived macrophages (BMDMs) under resting and inflammatory conditions. The effect of classical activators (lipopolysaccharide, LPS; interferon-gamma, IFN-γ) was further potentiated with hypoxic (5% O2) conditions. The activation of p44/42-extracellular signal-regulated kinases 1 and 2 (ERK1/2) and expression of caveolin-1, -2, and -3, hypoxia inducible factor-1 alpha (HIF-1α), as well as inducible nitric oxide synthase (iNOS) was monitored using the Western blot technique. The production of nitric oxide (NO) and tumor necrosis factor-alpha (TNFα) was analyzed by Griess method or ELISA, respectively. BMDMs were also transfected with siRNA against caveolin-2. Importantly, our study showed for the first time that BMDMs expressed only caveolin-2, and its level decreased after activation of macrophages with LPS, IFN-γ, and/or hypoxia. The expression of caveolin-2 negatively correlates with the iNOS and HIF-1α protein levels, as well as with the LPS/IFN-γ- and hypoxia-induced activation of ERK1/2. We concluded that caveolin-2 is most probably involved in regulation of pro-inflammatory responses of BMDMs, triggered via activation of ERK1/2.


Assuntos
Caveolina 2/genética , Caveolina 2/metabolismo , Expressão Gênica , Macrófagos/imunologia , Macrófagos/metabolismo , Animais , Sobrevivência Celular , Citocinas/metabolismo , Regulação da Expressão Gênica , Hipóxia/metabolismo , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , Masculino , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fenótipo , Interferência de RNA , RNA Interferente Pequeno/genética
20.
BMC Genet ; 16: 71, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26112043

RESUMO

Caveolae are small, "omega-shaped" invaginations at the plasma membrane of the cell which are involved in a variety of processes including cholesterol transport, potocytosis and cell signalling. Within caveolae there are caveolae-associated proteins, and changes in expression of these molecules have been described to play a role in the pathophysiology of various diseases including cancer and cardiovascular disease. Evidence is beginning to accumulate that epigenetic processes may regulate the expression of these caveolae related genes, and hence contribute to disease progression. Here, we summarize the current knowledge of the role of epigenetic modification in regulating the expression of these caveolae related genes and how this relates to changes in cellular physiology and in health and disease.


Assuntos
Cavéolas/metabolismo , Epigênese Genética , Predisposição Genética para Doença , Proteínas de Membrana/genética , Animais , Caveolina 1/genética , Caveolina 1/metabolismo , Caveolina 2/genética , Caveolina 2/metabolismo , Metilação de DNA , Regulação da Expressão Gênica , Humanos , Proteínas de Membrana/metabolismo , MicroRNAs/genética , Neoplasias/genética , Neoplasias/metabolismo , Interferência de RNA , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
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