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1.
BMC Public Health ; 24(1): 748, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459451

RESUMO

BACKGROUND: Perceiving oneself as obese has been associated with weight loss attempts. However, such a perception may not sufficiently drive significant weight reduction in many individuals. Hence, relying solely on the traditionally emphasized perceived risk of behavioral changes in obesity is challenging. This study used an extended parallel process model and a risk perception attitude framework to explore the influence of perceived risk and perceived efficacy on individual obesity knowledge and obesity prevention behaviors. METHODS: Data were obtained from 1,100 Korean adults aged 40-69 years through an online survey conducted in October 2022. Multinomial logistic regression and analysis of variance were employed to assess the relationships among perceived risk, perceived efficacy, obesity knowledge, and obesity prevention behaviors. RESULTS: Sex was associated with being underweight, overweight, and obese. Moreover, perceived severity was associated with obesity, whereas perceived susceptibility was associated with overweight and obese. Response efficacy was related to being overweight alone, whereas self-efficacy was associated with being underweight, overweight, and obese. The main effects of sex and perceived risk, and their interaction effect were statistically significant for obesity knowledge. Additionally, the main effects of sex, perceived risk, and perceived efficacy on obesity prevention behaviors were statistically significant. CONCLUSIONS: The extended parallel process model and risk perception attitude framework proved effective in classifying obesity based on body mass index, obesity knowledge, and obesity prevention behaviors.


Assuntos
Sobrepeso , Magreza , Adulto , Humanos , Obesidade/prevenção & controle , Índice de Massa Corporal , Redução de Peso , Percepção , República da Coreia/epidemiologia , Peso Corporal
3.
BMC Res Notes ; 16(1): 30, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36879317

RESUMO

OBJECTIVES: In 2012, Liu et al. reported that miR-34 is an age-related miRNA regulating age-associated events and long-term brain integrity in Drosophila. They demonstrated that modulating miR-34 and its downstream target, Eip74EF, showed beneficial effects on an age-related disease using a Drosophila model of Spinocerebellar ataxia type 3 expressing SCA3trQ78. These results imply that miR-34 could be a general genetic modifier and therapeutic candidate for age-related diseases. Thus, the goal of this study was to examine the effect of miR-34 and Eip47EF on another age-related Drosophila disease model. RESULTS: Using a Drosophila eye model expressing mutant Drosophila VCP (dVCP) that causes amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), or multisystem proteinopathy (MSP), we demonstrated that abnormal eye phenotypes generated by dVCPR152H were rescued by Eip74EF siRNA expression. Contrary to our expectations, miR-34 overexpression alone in the eyes with GMR-GAL4 resulted in complete lethality due to the leaky expression of GMR-GAL4 in other tissues. Interestingly, when miR-34 was co-expressed with dVCPR152H, a few survivors were produced; however, their eye degeneration was greatly exacerbated. Our data indicate that, while confirming that the downregulation of Eip74EF is beneficial to the dVCPR152HDrosophila eye model, the high expression level of miR-34 is actually toxic to the developing flies and the role of miR-34 in dVCPR152H-mediated pathogenesis is inconclusive in the GMR-GAL4 eye model. Identifying the transcriptional targets of Eip74EF might provide valuable insights into diseases caused by mutations in VCP such as ALS, FTD, and MSP.


Assuntos
Esclerose Lateral Amiotrófica , Proteínas de Drosophila , Demência Frontotemporal , MicroRNAs , Animais , Esclerose Lateral Amiotrófica/genética , Drosophila/genética , Proteínas de Drosophila/genética , Demência Frontotemporal/genética , MicroRNAs/genética , Fenótipo , Fatores de Transcrição
4.
Nanomaterials (Basel) ; 12(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35630867

RESUMO

Transition metal dichalcogenide-based quantum dots are promising materials for applications in diverse fields, such as sensors, electronics, catalysis, and biomedicine, because of their outstanding physicochemical properties. In this study, we propose bio-imaging characteristics through utilizing water-soluble MoS2 quantum dots (MoS2-QDs) with two different sizes (i.e., ~5 and ~10 nm). The structural and optical properties of the fabricated metallic phase MoS2-QDs (m-MoS2-QDs) were characterized by transmission electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, UV-vis absorption spectroscopy, and photoluminescence. The synthesized m-MoS2-QDs showed clear photophysical characteristic peaks derived from the quantum confinement effect and defect sites, such as oxygen functional groups. When the diameter of the synthesized m-MoS2-QD was decreased, the emission peak was blue-shifted from 436 to 486 nm under excitation by a He-Cd laser (325 nm). Density functional theory calculations confirmed that the size decrease of m-MoS2-QDs led to an increase in the bandgap because of quantum confinement effects. In addition, when incorporated into the bio-imaging of HeLa cells, m-MoS2-QDs were quite biocompatible with bright luminescence and exhibited low toxicity. Our results are commercially applicable for achieving high-performance bio-imaging probes.

6.
Nat Commun ; 12(1): 1924, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33772006

RESUMO

Mutations in coiled-coil-helix-coiled-coil-helix domain containing 10 (CHCHD10) can cause amyotrophic lateral sclerosis and frontotemporal dementia (ALS-FTD). However, the underlying mechanisms are unclear. Here, we generate CHCH10S59L-mutant Drosophila melanogaster and HeLa cell lines to model CHCHD10-associated ALS-FTD. The CHCHD10S59L mutation results in cell toxicity in several tissues and mitochondrial defects. CHCHD10S59L independently affects the TDP-43 and PINK1 pathways. CHCHD10S59L expression increases TDP-43 insolubility and mitochondrial translocation. Blocking TDP-43 mitochondrial translocation with a peptide inhibitor reduced CHCHD10S59L-mediated toxicity. While genetic and pharmacological modulation of PINK1 expression and activity of its substrates rescues and mitigates the CHCHD10S59L-induced phenotypes and mitochondrial defects, respectively, in both Drosophila and HeLa cells. Our findings suggest that CHCHD10S59L-induced TDP-43 mitochondrial translocation and chronic activation of PINK1-mediated pathways result in dominant toxicity, providing a mechanistic insight into the CHCHD10 mutations associated with ALS-FTD.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Demência Frontotemporal/genética , Proteínas Mitocondriais/genética , Mutação , Proteínas Serina-Treonina Quinases/genética , Sequência de Aminoácidos , Esclerose Lateral Amiotrófica/metabolismo , Animais , Animais Geneticamente Modificados , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Demência Frontotemporal/metabolismo , Células HEK293 , Células HeLa , Humanos , Microscopia Confocal , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transporte Proteico/genética , Homologia de Sequência de Aminoácidos
7.
Nat Med ; 24(4): 427-437, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29505030

RESUMO

Spinal bulbar muscular atrophy (SBMA) is a motor neuron disease caused by toxic gain of function of the androgen receptor (AR). Previously, we found that co-regulator binding through the activation function-2 (AF2) domain of AR is essential for pathogenesis, suggesting that AF2 may be a potential drug target for selective modulation of toxic AR activity. We screened previously identified AF2 modulators for their ability to rescue toxicity in a Drosophila model of SBMA. We identified two compounds, tolfenamic acid (TA) and 1-[2-(4-methylphenoxy)ethyl]-2-[(2-phenoxyethyl)sulfanyl]-1H-benzimidazole (MEPB), as top candidates for rescuing lethality, locomotor function and neuromuscular junction defects in SBMA flies. Pharmacokinetic analyses in mice revealed a more favorable bioavailability and tissue retention of MEPB compared with TA in muscle, brain and spinal cord. In a preclinical trial in a new mouse model of SBMA, MEPB treatment yielded a dose-dependent rescue from loss of body weight, rotarod activity and grip strength. In addition, MEPB ameliorated neuronal loss, neurogenic atrophy and testicular atrophy, validating AF2 modulation as a potent androgen-sparing strategy for SBMA therapy.


Assuntos
Atrofia Muscular Espinal/patologia , Degeneração Neural/patologia , Receptores Androgênicos/química , Receptores Androgênicos/metabolismo , Animais , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Proteínas Correpressoras/metabolismo , Modelos Animais de Doenças , Drosophila melanogaster , Células HEK293 , Humanos , Masculino , Camundongos Transgênicos , Atrofia Muscular Espinal/tratamento farmacológico , Degeneração Neural/tratamento farmacológico , Fenótipo , Projetos Piloto , Domínios Proteicos , Expansão das Repetições de Trinucleotídeos/genética , ortoaminobenzoatos/farmacologia , ortoaminobenzoatos/uso terapêutico
8.
Cell ; 167(3): 774-788.e17, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27768896

RESUMO

Expansion of a hexanucleotide repeat GGGGCC (G4C2) in C9ORF72 is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Transcripts carrying (G4C2) expansions undergo unconventional, non-ATG-dependent translation, generating toxic dipeptide repeat (DPR) proteins thought to contribute to disease. Here, we identify the interactome of all DPRs and find that arginine-containing DPRs, polyGly-Arg (GR) and polyPro-Arg (PR), interact with RNA-binding proteins and proteins with low complexity sequence domains (LCDs) that often mediate the assembly of membrane-less organelles. Indeed, most GR/PR interactors are components of membrane-less organelles such as nucleoli, the nuclear pore complex and stress granules. Genetic analysis in Drosophila demonstrated the functional relevance of these interactions to DPR toxicity. Furthermore, we show that GR and PR altered phase separation of LCD-containing proteins, insinuating into their liquid assemblies and changing their material properties, resulting in perturbed dynamics and/or functions of multiple membrane-less organelles.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Dipeptídeos/metabolismo , Demência Frontotemporal/metabolismo , Proteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Esclerose Lateral Amiotrófica/genética , Animais , Proteína C9orf72 , Nucléolo Celular/metabolismo , Grânulos Citoplasmáticos/metabolismo , Expansão das Repetições de DNA , Dipeptídeos/genética , Drosophila melanogaster/genética , Demência Frontotemporal/genética , Humanos , Membranas Intracelulares/metabolismo , Poro Nuclear/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , Proteínas/genética
9.
Hum Mol Genet ; 25(5): 936-50, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26744327

RESUMO

Adult-onset inherited myopathies with similar pathological features, including hereditary inclusion body myopathy (hIBM) and limb-girdle muscular dystrophy (LGMD), are a genetically heterogeneous group of muscle diseases. It is unclear whether these inherited myopathies initiated by mutations in distinct classes of genes are etiologically related. Here, we exploit a genetic model system to establish a mechanistic link between diseases caused by mutations in two distinct genes, hnRNPA2B1 and DNAJB6. Hrb98DE and mrj are the Drosophila melanogaster homologs of human hnRNPA2B1 and DNAJB6, respectively. We introduced disease-homologous mutations to Hrb98DE, thus capturing mutation-dependent phenotypes in a genetically tractable model system. Ectopic expression of the disease-associated mutant form of hnRNPA2B1 or Hrb98DE in fly muscle resulted in progressive, age-dependent cytoplasmic inclusion pathology, as observed in humans with hnRNPA2B1-related myopathy. Cytoplasmic inclusions consisted of hnRNPA2B1 or Hrb98DE protein in association with the stress granule marker ROX8 and additional endogenous RNA-binding proteins (RBPs), suggesting that these pathological inclusions are related to stress granules. Notably, TDP-43 was also recruited to these cytoplasmic inclusions. Remarkably, overexpression of MRJ rescued this phenotype and suppressed the formation of cytoplasmic inclusions, whereas reduction of endogenous MRJ by a classical loss of function allele enhanced it. Moreover, wild-type, but not disease-associated, mutant forms of MRJ interacted with RBPs after heat shock and prevented their accumulation in aggregates. These results indicate both genetic and physical interactions between disease-linked RBPs and DNAJB6/mrj, suggesting etiologic overlap between the pathogenesis of hIBM and LGMD initiated by mutations in hnRNPA2B1 and DNAJB6.


Assuntos
Contratura/congênito , Drosophila melanogaster/genética , Proteínas de Choque Térmico HSP40/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Chaperonas Moleculares/genética , Distrofia Muscular do Cíngulo dos Membros/genética , Miosite de Corpos de Inclusão/congênito , Proteínas do Tecido Nervoso/genética , Oftalmoplegia/genética , Adulto , Idade de Início , Sequência de Aminoácidos , Animais , Contratura/genética , Contratura/metabolismo , Contratura/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP40/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Humanos , Chaperonas Moleculares/metabolismo , Dados de Sequência Molecular , Músculos/metabolismo , Músculos/patologia , Distrofia Muscular do Cíngulo dos Membros/metabolismo , Distrofia Muscular do Cíngulo dos Membros/patologia , Mutação , Miosite de Corpos de Inclusão/genética , Miosite de Corpos de Inclusão/metabolismo , Miosite de Corpos de Inclusão/patologia , Proteínas do Tecido Nervoso/metabolismo , Oftalmoplegia/metabolismo , Oftalmoplegia/patologia , Fenótipo , Ligação Proteica , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transdução de Sinais
10.
Nature ; 525(7567): 129-33, 2015 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26308899

RESUMO

The GGGGCC (G4C2) repeat expansion in a noncoding region of C9orf72 is the most common cause of sporadic and familial forms of amyotrophic lateral sclerosis and frontotemporal dementia. The basis for pathogenesis is unknown. To elucidate the consequences of G4C2 repeat expansion in a tractable genetic system, we generated transgenic fly lines expressing 8, 28 or 58 G4C2-repeat-containing transcripts that do not have a translation start site (AUG) but contain an open-reading frame for green fluorescent protein to detect repeat-associated non-AUG (RAN) translation. We show that these transgenic animals display dosage-dependent, repeat-length-dependent degeneration in neuronal tissues and RAN translation of dipeptide repeat (DPR) proteins, as observed in patients with C9orf72-related disease. This model was used in a large-scale, unbiased genetic screen, ultimately leading to the identification of 18 genetic modifiers that encode components of the nuclear pore complex (NPC), as well as the machinery that coordinates the export of nuclear RNA and the import of nuclear proteins. Consistent with these results, we found morphological abnormalities in the architecture of the nuclear envelope in cells expressing expanded G4C2 repeats in vitro and in vivo. Moreover, we identified a substantial defect in RNA export resulting in retention of RNA in the nuclei of Drosophila cells expressing expanded G4C2 repeats and also in mammalian cells, including aged induced pluripotent stem-cell-derived neurons from patients with C9orf72-related disease. These studies show that a primary consequence of G4C2 repeat expansion is the compromise of nucleocytoplasmic transport through the nuclear pore, revealing a novel mechanism of neurodegeneration.


Assuntos
Transporte Ativo do Núcleo Celular/genética , Expansão das Repetições de DNA/genética , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Fases de Leitura Aberta/genética , Proteínas/genética , Transporte de RNA/genética , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Animais , Animais Geneticamente Modificados , Proteína C9orf72 , Drosophila melanogaster/genética , Olho/metabolismo , Feminino , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Células HeLa , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Músculos/citologia , Músculos/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Poro Nuclear/genética , Poro Nuclear/metabolismo , Poro Nuclear/patologia , Fenótipo , Biossíntese de Proteínas , RNA/genética , RNA/metabolismo , Glândulas Salivares/citologia , Glândulas Salivares/metabolismo , Glândulas Salivares/patologia
11.
Hepatogastroenterology ; 61(134): 1494-500, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25436332

RESUMO

BACKGROUND/AIMS: Autophagy plays critical roles in both cell survival and cell death. Beclin-1, a key modulator of autophagy function, is considered a haploinsufficient tumor suppressor. The role of Beclin-1 expression in cancer is still controversial. Some studies favor the idea that autophagy suppresses tumor development, whereas other researchers suggest that autophagy enhances tumorigenesis. The expression and function of Beclin-1 in gallbladder cancer (GBCA) remain largely unknown. METHODOLOGY: Methodology: We performed immunohistochemical staining for Beclin-1 in 119 GBCA cases, and investigated whether Beclin-1 expression correlated with clinicopathologic characteristics and prognosis of patients. RESULTS: Beclin-1 was expressed in the cytoplasm of cancer cells with occasional nuclear staining in 53 (44.5%) of the 119 cases of GBCA with no expression in adjacent normal epithelial cells. Increased expression of Beclin-1 was significantly associated with longer survival rate of patients with GBCA in univariate (p=0.006) and multivariate analyses (p=0.005). There is no association between Beclin-1 expression and clinicopathologic characteristics. CONCLUSIONS: Beclin-1 was highly expressed in GBCA, and positive expression in cancer cells was significantly related with favorable prognosis in GBCA patients. Our results suggest that the expression of Beclin-1 may be an independent predictive marker of favorable prognosis in GBCA.


Assuntos
Proteínas Reguladoras de Apoptose/análise , Biomarcadores Tumorais/análise , Neoplasias da Vesícula Biliar/química , Proteínas de Membrana/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína Beclina-1 , Distribuição de Qui-Quadrado , Feminino , Neoplasias da Vesícula Biliar/mortalidade , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/terapia , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco , Regulação para Cima
12.
IEEE Trans Image Process ; 22(12): 5408, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23974628

RESUMO

This correspondence points out that in [1] there are some errors in two important formulas and the performance of the proposed singular value decomposition (SVD) feature is severely overestimated. It also presents a modified SVD feature which competes with the Gabor feature.


Assuntos
Algoritmos , Inteligência Artificial , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Processamento de Sinais Assistido por Computador
13.
Biomed Res Int ; 2013: 527534, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23841074

RESUMO

Gallbladder carcinoma (GBCA) is one of the most aggressive malignancies. It is usually diagnosed at an advanced stage, and prognosis remains poor despite advances in imaging techniques and aggressive surgical treatment. Overexpression of multidrug resistance-associated proteins (MRPs) in tumor cells is a major cause of the intrinsic multidrug resistance phenotype. Despite the documented importance of MRP expression in many carcinomas, the prognostic significance of MRP2 expression in primary GBCA is not known. Immunostaining for MRP2 was performed on tissue samples obtained from 143 patients with GBCA. We examined the association between MRP expression and clinicopathological characteristics and outcome of patients with GBCA. GBCA demonstrated MRP2 immunoreactivity in the apicolateral membranes of epithelial cells. MRP2 expression was positive in 53.1% (76/143) of GBCA samples. Positive MRP2 expression was significantly associated with the presence of local recurrence (P = 0.038), lymphatic invasion (P = 0.038), vascular invasion (P = 0.023), and perineural invasion (P = 0.006). In addition, the median survival time of patients with MRP2-positive GBCA (15 months) was significantly shorter than that of patients with MRP2-negative GBCA (85 months, P = 0.011). We found that the expression of MRP2 in GBCA contributed to aggressive tumor behavior and poor prognosis, suggesting that MRP2 expression can be used as a potential prognostic biomarker of GBCA.


Assuntos
Carcinoma/genética , Resistência a Múltiplos Medicamentos/genética , Neoplasias da Vesícula Biliar/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/biossíntese , Idoso , Carcinoma/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Neoplasias da Vesícula Biliar/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Prognóstico
14.
Neuron ; 78(1): 65-80, 2013 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23498974

RESUMO

Mutations in VCP cause multisystem degeneration impacting the nervous system, muscle, and/or bone. Patients may present with ALS, Parkinsonism, frontotemporal dementia, myopathy, Paget's disease, or a combination of these. The disease mechanism is unknown. We developed a Drosophila model of VCP mutation-dependent degeneration. The phenotype is reminiscent of PINK1 and parkin mutants, including a pronounced mitochondrial defect. Indeed, VCP interacts genetically with the PINK1/parkin pathway in vivo. Paradoxically, VCP complements PINK1 deficiency but not parkin deficiency. The basis of this paradox is resolved by mechanistic studies in vitro showing that VCP recruitment to damaged mitochondria requires Parkin-mediated ubiquitination of mitochondrial targets. VCP recruitment coincides temporally with mitochondrial fission, and VCP is required for proteasome-dependent degradation of Mitofusins in vitro and in vivo. Further, VCP and its adaptor Npl4/Ufd1 are required for clearance of damaged mitochondria via the PINK1/Parkin pathway, and this is impaired by pathogenic mutations in VCP.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Drosophila/metabolismo , Mitocôndrias/genética , Neurônios/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Adaptadoras de Transporte Vesicular , Adenosina Trifosfatases/genética , Animais , Animais Geneticamente Modificados , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Proteínas de Ciclo Celular/genética , Células Cultivadas , Drosophila , Proteínas de Drosophila/genética , Embrião de Mamíferos , Inibidores Enzimáticos/farmacologia , GTP Fosfo-Hidrolases/metabolismo , Gânglios Espinais/citologia , Regulação da Expressão Gênica/genética , Proteínas de Choque Térmico HSP72/genética , Humanos , Imunoprecipitação , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intracelular , Leupeptinas/farmacologia , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Mutação/genética , Junção Neuromuscular/genética , Junção Neuromuscular/metabolismo , Neurônios/ultraestrutura , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Fosfatases/genética , Proteínas/metabolismo , Ionóforos de Próton/farmacologia , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/farmacologia , Fatores de Tempo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/genética , Proteína com Valosina
15.
Nature ; 495(7442): 467-73, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23455423

RESUMO

Algorithms designed to identify canonical yeast prions predict that around 250 human proteins, including several RNA-binding proteins associated with neurodegenerative disease, harbour a distinctive prion-like domain (PrLD) enriched in uncharged polar amino acids and glycine. PrLDs in RNA-binding proteins are essential for the assembly of ribonucleoprotein granules. However, the interplay between human PrLD function and disease is not understood. Here we define pathogenic mutations in PrLDs of heterogeneous nuclear ribonucleoproteins (hnRNPs) A2B1 and A1 in families with inherited degeneration affecting muscle, brain, motor neuron and bone, and in one case of familial amyotrophic lateral sclerosis. Wild-type hnRNPA2 (the most abundant isoform of hnRNPA2B1) and hnRNPA1 show an intrinsic tendency to assemble into self-seeding fibrils, which is exacerbated by the disease mutations. Indeed, the pathogenic mutations strengthen a 'steric zipper' motif in the PrLD, which accelerates the formation of self-seeding fibrils that cross-seed polymerization of wild-type hnRNP. Notably, the disease mutations promote excess incorporation of hnRNPA2 and hnRNPA1 into stress granules and drive the formation of cytoplasmic inclusions in animal models that recapitulate the human pathology. Thus, dysregulated polymerization caused by a potent mutant steric zipper motif in a PrLD can initiate degenerative disease. Related proteins with PrLDs should therefore be considered candidates for initiating and perhaps propagating proteinopathies of muscle, brain, motor neuron and bone.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Demência Frontotemporal/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/química , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Distrofia Muscular do Cíngulo dos Membros/genética , Proteínas Mutantes/genética , Mutação/genética , Miosite de Corpos de Inclusão/genética , Osteíte Deformante/genética , Príons/química , Sequência de Aminoácidos , Esclerose Lateral Amiotrófica/metabolismo , Animais , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Células HeLa , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Humanos , Corpos de Inclusão/genética , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Masculino , Camundongos , Dados de Sequência Molecular , Distrofia Muscular do Cíngulo dos Membros/metabolismo , Distrofia Muscular do Cíngulo dos Membros/patologia , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Miosite de Corpos de Inclusão/metabolismo , Miosite de Corpos de Inclusão/patologia , Osteíte Deformante/metabolismo , Osteíte Deformante/patologia , Fatores de Terminação de Peptídeos/química , Fatores de Terminação de Peptídeos/genética , Fatores de Terminação de Peptídeos/metabolismo , Príons/genética , Príons/metabolismo , Estrutura Terciária de Proteína/genética , RNA/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
16.
J Cell Sci ; 125(Pt 16): 3752-64, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22573823

RESUMO

Neuronal function depends on the retrograde relay of growth and survival signals from the synaptic terminal, where the neuron interacts with its targets, to the nucleus, where gene transcription is regulated. Activation of the Bone Morphogenetic Protein (BMP) pathway at the Drosophila larval neuromuscular junction results in nuclear accumulation of the phosphorylated form of the transcription factor Mad in the motoneuron nucleus. This in turn regulates transcription of genes that control synaptic growth. How BMP signaling at the synaptic terminal is relayed to the cell body and nucleus of the motoneuron to regulate transcription is unknown. We show that the BMP receptors are endocytosed at the synaptic terminal and transported retrogradely along the axon. Furthermore, this transport is dependent on BMP pathway activity, as it decreases in the absence of ligand or receptors. We further demonstrate that receptor traffic is severely impaired when Dynein motors are inhibited, a condition that has previously been shown to block BMP pathway activation. In contrast to these results, we find no evidence for transport of phosphorylated Mad along the axons, and axonal traffic of Mad is not affected in mutants defective in BMP signaling or retrograde transport. These data support a model in which complexes of activated BMP receptors are actively transported along the axon towards the cell body to relay the synaptogenic signal, and that phosphorylated Mad at the synaptic terminal and cell body represent two distinct molecular populations.


Assuntos
Transporte Axonal/fisiologia , Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas de Drosophila/metabolismo , Neurônios Motores/metabolismo , Terminações Pré-Sinápticas/metabolismo , Animais , Dineínas do Axonema/metabolismo , Axônios/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas/genética , Proteínas de Ligação a DNA/metabolismo , Drosophila , Proteínas de Drosophila/genética , Endossomos/genética , Endossomos/metabolismo , Neurônios Motores/citologia , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes de Fusão/análise , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo
17.
Dev Neurobiol ; 72(12): 1541-58, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22467519

RESUMO

Refinement of neural circuits during development requires formation and elimination of synaptic connections, a process governed by activity-dependent mechanisms and developmental genetic programs. Bone Morphogenetic Protein (BMP) retrograde signaling through the type II receptor Wishful thinking (Wit) is essential for synaptic growth and functional development of the Drosophila larval neuromuscular junction. However, little is known about the genes that are regulated by the pathway to effect synaptic growth and proper synaptic transmission. We have identified a transcriptional target of wit (twit), whose expression in motoneurons depends on Wit activity. Null twit mutants are viable and fertile, but recapitulate some of the electrophysiological phenotypes of wit mutants, such as decreased frequency and amplitude of miniature excitatory junction potentials. Other wit phenotypes, such as decreased synaptic terminal size and evoked excitatory junction potentials, are not found in twit mutants, suggesting that homeostatic compensation of presynaptic release is intact in twit mutants and that Wit regulates additional genes to accomplish proper synaptic maturation. Twit is a glycosylphosphatidylinositol-anchored protein of the Lymphocyte antigen 6 family (Ly-6), and neuronal expression of a twit transgene rescues twit's mutant phenotypes. Importantly, twit expression partially rescues diminished frequency of miniature excitatory synaptic potentials in wit mutants. This further supports the conclusions that Twit is signaling in larval motoneurons and an essential effector of the retrograde BMP signal. Taken together, our results suggest that retrograde BMP signaling regulates spontaneous neurotransmitter release by activating the transcription of the Ly-6 gene twit.


Assuntos
Antígenos Ly/genética , Proteínas de Drosophila/genética , Drosophila/genética , Proteínas Ligadas por GPI/genética , Neurogênese/genética , Junção Neuromuscular/metabolismo , Neuropeptídeos/genética , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Antígenos Ly/metabolismo , Western Blotting , Drosophila/embriologia , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Eletrofisiologia , Imunofluorescência , Proteínas Ligadas por GPI/metabolismo , Hibridização In Situ , Dados de Sequência Molecular , Neurônios Motores/metabolismo , Junção Neuromuscular/embriologia , Neuropeptídeos/metabolismo , Neurotransmissores/metabolismo , Receptores de Superfície Celular/metabolismo , Transmissão Sináptica/genética , Transfecção
18.
Dev Dyn ; 239(9): 2413-25, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20652954

RESUMO

Bone Morphogenetic Protein (BMP) signaling mediated by the receptor Wishful thinking (Wit) is essential for nervous system development in Drosophila. Mutants lacking wit function show defects in neuromuscular junction development and function, specification of neurosecretory phenotypes, and eclosion behavior that result in lethality. The ligand is Glass bottom boat, the Drosophila ortholog of mammalian BMP-7, which acts as a retrograde signal through the Wit receptor. In order to identify transcriptional targets of the BMP pathway in the Drosophila nervous system, we have analyzed the gene expression profile of wit mutant larval central nervous system. Genes differentially expressed identified by microarray analysis have been verified by quantitative PCR and studied by in situ hybridization. Among the genes thus identified, we find solute transporters, neuropeptides, mitochondrial proteins, and novel genes. In addition, several genes are regulated by wit in an isoform-specific manner that suggest regulation of alternative splicing by BMP signaling.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Sistema Nervoso Central , Drosophila melanogaster , Transdução de Sinais/fisiologia , Animais , Proteínas Morfogenéticas Ósseas/genética , Sistema Nervoso Central/crescimento & desenvolvimento , Sistema Nervoso Central/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Análise em Microsséries , Dados de Sequência Molecular , Splicing de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Reprodutibilidade dos Testes , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
19.
Methods Mol Biol ; 371: 111-41, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17634578

RESUMO

Nutrigenomics is the study of gene-nutrient interactions and how they affect the health and metabolism of an organism. Combining nutrigenomics with longevity studies is a natural extension and promises to help identify mechanisms whereby nutrients affect the aging process, life span, and, with the incorporation of age-dependent functional measures, health span. The topics we discuss in this chapter are genetic techniques, dietary manipulations, metabolic studies, and microarray analysis methods to investigate how nutrition affects gene expression, life span, triglyceride levels, total protein levels, and live weight in Drosophila. To better illustrate nutrigenomic techniques, we analyzed Drosophila larvae or adults fed control diets (high sucrose) and compared these with larvae or adults fed diets high in the saturated fat palmitic acid, soy, or 95% lean ground beef. The main results of these studies are, surprisingly, that triglyceride and total protein levels are significantly decreased by the beef diet in all adults, and total protein levels are significantly increased in male flies fed the soy diet. Furthermore, and less surprisingly, we found that all three experimental diets significantly decreased longevity and increased the length of time to develop from egg to adult. We also describe preliminary microarray results with adult flies fed the different diets, which suggest that only about 2-3% of the approx 18,000 genes have significantly altered mRNA expression levels compared with flies fed a control sucrose diet. The significance of these results and other types of nutrigenomics and longevity analyses is discussed.


Assuntos
Dieta , Regulação da Expressão Gênica/fisiologia , Genes de Insetos/fisiologia , Longevidade/fisiologia , RNA Mensageiro/biossíntese , Animais , Drosophila melanogaster , Inibidores Enzimáticos/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Larva/genética , Larva/metabolismo , Longevidade/efeitos dos fármacos , Masculino , Ácido Palmítico/farmacologia , RNA Mensageiro/genética , Sacarose/farmacologia , Edulcorantes/farmacologia
20.
J Vet Sci ; 6(3): 227-30, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16131826

RESUMO

In view of the high prevalence rate of bovine leukemia virus (BLV) infections in cattle over the entire country, a large dairy farm in Chungnam province was chosen and 'test and segregate' program was instituted. On July 1999, ELISA test was performed on 491 animals on the farm and only 163 cattle (139 adult cows, 18 female and 6 male calves)were BLV-seronegative. From February 2000 through April 2004, the seronegative group was placed in barns 1,500 to 2,000 m from seropositive group and thereafter tested at 3-to 5-month intervals by ELISA. Animals seroconverted in consecutive tests were removed from the seronegative group immediately after the detection of anti-BLV antibodies. The changes in management were aimed at preventing iatrogenic transfer of blood between cattle. Replacement heifers imported from other countries and calves born at the farm were repeatedly tested by ELISA, and only seronegative animals were introduced into the group. As of April 2004, there were 311 cattle in the BLV seronegative group of the farm. Twenty four cows of the initial 139 adult cows were seroconverted in 2000, and no seropositive animals were found since February 2001. Follow up of the group, from which all seropositive cattle were moved to a separate location, revealed no recurrence of BLV infection for three years. The approach in the present study might be valuable for Korean producers who would like to move toward a BLV-negative status.


Assuntos
Criação de Animais Domésticos , Anticorpos Antivirais/sangue , Leucose Enzoótica Bovina/prevenção & controle , Vírus da Leucemia Bovina/isolamento & purificação , Animais , Bovinos , Feminino , Coreia (Geográfico) , Masculino , Prevalência
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