Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Am J Hum Genet ; 108(7): 1301-1317, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34038740

RESUMO

Human C2orf69 is an evolutionarily conserved gene whose function is unknown. Here, we report eight unrelated families from which 20 children presented with a fatal syndrome consisting of severe autoinflammation and progredient leukoencephalopathy with recurrent seizures; 12 of these subjects, whose DNA was available, segregated homozygous loss-of-function C2orf69 variants. C2ORF69 bears homology to esterase enzymes, and orthologs can be found in most eukaryotic genomes, including that of unicellular phytoplankton. We found that endogenous C2ORF69 (1) is loosely bound to mitochondria, (2) affects mitochondrial membrane potential and oxidative respiration in cultured neurons, and (3) controls the levels of the glycogen branching enzyme 1 (GBE1) consistent with a glycogen-storage-associated mitochondriopathy. We show that CRISPR-Cas9-mediated inactivation of zebrafish C2orf69 results in lethality by 8 months of age due to spontaneous epileptic seizures, which is preceded by persistent brain inflammation. Collectively, our results delineate an autoinflammatory Mendelian disorder of C2orf69 deficiency that disrupts the development/homeostasis of the immune and central nervous systems.


Assuntos
Encefalite/genética , Doenças Mitocondriais/genética , Animais , Evolução Biológica , Sistemas CRISPR-Cas , Linhagem Celular , Encefalite/mortalidade , Feminino , Genes Recessivos , Glicogênio/metabolismo , Humanos , Inflamação/genética , Masculino , Proteínas de Membrana/genética , Doenças Mitocondriais/mortalidade , Linhagem , Convulsões/genética , Convulsões/mortalidade , Peixe-Zebra/genética
3.
Matrix Biol ; 118: 110-128, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36924903

RESUMO

Imbalance of collagen I expression results in severe pathologies. Apart from activation by the TGFß-receptor/Smad pathway, control of collagen I expression remains poorly understood. Here, we used human dermal fibroblasts expressing a mCherry fluorescent protein driven by endogenous COL1A1 promoter to functionally screen the kinome and phosphatome. We identify 8 negative regulators, revealing that collagen is under tonic repression. The cell surface receptor BDKRB2 represses collagen I and other pro-fibrotic genes. Interestingly, it also promotes other basal membrane ECM genes. This function is independent of the natural ligand, bradykinin, and of SMAD2/3 factors, instead requiring constant ERK1/2 repression. TGFß stimulation induces rapid BDKRB2 transcriptional downregulation. Human fibrotic fibroblasts have reduced BDKRB2 levels and enhancing its expression in keloid fibroblasts represses COL1A1. We propose that tonic signalling by BDKRB2 prevents collagen overproduction in skin fibroblasts.


Assuntos
Colágeno Tipo I , Pele , Humanos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Pele/metabolismo , Colágeno/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Células Cultivadas , Fibroblastos/metabolismo , Receptores da Bradicinina/metabolismo
4.
Sci Rep ; 10(1): 19723, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33184327

RESUMO

Type I collagen is a key protein of most connective tissue and its up-regulation is required for wound healing but is also involved in fibrosis. Control of expression of this collagen remains poorly understood apart from Transforming Growth Factor beta (TGF-ß1)-mediated induction. To generate a sensitive, practical, robust, image-based high-throughput-compatible reporter system, we genetically inserted a short-lived fluorescence reporter downstream of the endogenous type I collagen (COL1A1) promoter in skin fibroblasts. Using a variety of controls, we demonstrate that the cell line faithfully reports changes in type I collagen expression with at least threefold enhanced sensitivity compared to endogenous collagen monitoring. We use this assay to test the potency of anti-fibrotic compounds and screen siRNAs for regulators of TGF-ß1-induced type I collagen expression. We propose our reporter cell line, Red-COLA1, as a new efficient tool to study type I collagen transcriptional regulation.


Assuntos
Colágeno Tipo I/metabolismo , Fibroblastos/metabolismo , Fibrose/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Indóis/farmacologia , Proteínas Luminescentes/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Células Cultivadas , Colágeno/metabolismo , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Fibroblastos/citologia , Fibrose/tratamento farmacológico , Fibrose/patologia , Ensaios de Triagem em Larga Escala , Humanos , Proteínas Luminescentes/genética , Regiões Promotoras Genéticas , RNA Interferente Pequeno/genética , Transcrição Gênica , Fator de Crescimento Transformador beta1/genética , Proteína Vermelha Fluorescente
5.
Nat Commun ; 6: 8218, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26356418

RESUMO

Endocytosis directs molecular cargo along three main routes: recycling to the cell surface, transport to the Golgi apparatus or degradation in endolysosomes. Pseudomonas exotoxin A (PE) is a bacterial protein that typically traffics to the Golgi and then the endoplasmic reticulum before translocating to the cytosol. Here we show that a substantial fraction of internalized PE is also located in nuclear envelope-associated endosomes (NAE), which display limited mobility, exhibit a propensity to undergo fusion and readily discharge their contents into the nuclear envelope. Electron microscopy and protein trapping in the nucleus indicate that NAE mediate PE transfer into the nucleoplasm. RNAi screening further revealed that NAE-mediated transfer depends on the nuclear envelope proteins SUN1 and SUN2, as well as the Sec61 translocon complex. These data reveal a novel endosomal route from the cell surface to the nucleoplasm that facilitates the accumulation of extracellular and cell surface proteins in the nucleus.


Assuntos
ADP Ribose Transferases/metabolismo , Toxinas Bacterianas/metabolismo , Núcleo Celular/metabolismo , Endocitose , Endossomos/metabolismo , Exotoxinas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/genética , Membrana Nuclear/metabolismo , Proteínas Nucleares/genética , Fatores de Virulência/metabolismo , Linhagem Celular Tumoral , Citosol/metabolismo , Retículo Endoplasmático/metabolismo , Imunofluorescência , Técnicas de Silenciamento de Genes , Complexo de Golgi/metabolismo , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Microscopia Confocal , Microscopia Eletrônica , Proteínas Associadas aos Microtúbulos/metabolismo , Sinais de Localização Nuclear , Proteínas Nucleares/metabolismo , Transporte Proteico , Canais de Translocação SEC , Exotoxina A de Pseudomonas aeruginosa
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA