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1.
EMBO J ; 41(17): e110784, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35859387

RESUMO

The mitochondrial intermembrane space protein AIFM1 has been reported to mediate the import of MIA40/CHCHD4, which forms the import receptor in the mitochondrial disulfide relay. Here, we demonstrate that AIFM1 and MIA40/CHCHD4 cooperate beyond this MIA40/CHCHD4 import. We show that AIFM1 and MIA40/CHCHD4 form a stable long-lived complex in vitro, in different cell lines, and in tissues. In HEK293 cells lacking AIFM1, levels of MIA40 are unchanged, but the protein is present in the monomeric form. Monomeric MIA40 neither efficiently interacts with nor mediates the import of specific substrates. The import defect is especially severe for NDUFS5, a subunit of complex I of the respiratory chain. As a consequence, NDUFS5 accumulates in the cytosol and undergoes rapid proteasomal degradation. Lack of mitochondrial NDUFS5 in turn results in stalling of complex I assembly. Collectively, we demonstrate that AIFM1 serves two overlapping functions: importing MIA40/CHCHD4 and constituting an integral part of the disulfide relay that ensures efficient interaction of MIA40/CHCHD4 with specific substrates.


Assuntos
Fator de Indução de Apoptose , Complexo I de Transporte de Elétrons , Proteínas de Transporte da Membrana Mitocondrial , Fator de Indução de Apoptose/metabolismo , Dissulfetos/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Células HEK293 , Humanos , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Oxirredução , Transporte Proteico
2.
EMBO J ; 40(21): e108648, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34542926

RESUMO

So-called ρ0 cells lack mitochondrial DNA and are therefore incapable of aerobic ATP synthesis. How cells adapt to survive ablation of oxidative phosphorylation remains poorly understood. Complexome profiling analysis of ρ0 cells covered 1,002 mitochondrial proteins and revealed changes in abundance and organization of numerous multiprotein complexes including previously not described assemblies. Beyond multiple subassemblies of complexes that would normally contain components encoded by mitochondrial DNA, we observed widespread reorganization of the complexome. This included distinct changes in the expression pattern of adenine nucleotide carrier isoforms, other mitochondrial transporters, and components of the protein import machinery. Remarkably, ablation of mitochondrial DNA hardly affected the complexes organizing cristae junctions indicating that the altered cristae morphology in ρ0 mitochondria predominantly resulted from the loss of complex V dimers required to impose narrow curvatures to the inner membrane. Our data provide a comprehensive resource for in-depth analysis of remodeling of the mitochondrial complexome in response to respiratory deficiency.


Assuntos
Adaptação Fisiológica , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Complexos Multiproteicos/genética , Trifosfato de Adenosina/metabolismo , Linhagem Celular Tumoral , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Expressão Gênica , Humanos , Mitocôndrias/patologia , Membranas Mitocondriais/química , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/deficiência , Complexos Multiproteicos/deficiência , Osteoblastos/metabolismo , Osteoblastos/patologia , Fosforilação Oxidativa
3.
New Phytol ; 243(1): 466-476, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38757753

RESUMO

Crops generally have seeds larger than their wild progenitors´ and with reduced dormancy. In wild plants, seed mass and allocation to the seed coat (a proxy for physical dormancy) scale allometrically so that larger seeds tend to allocate less to the coats. Larger seeds and lightweight coats might thus have evolved as correlated traits in crops. We tested whether 34 crops and 22 of their wild progenitors fit the allometry described in the literature, which would indicate co-selection of both traits during crop evolution. Deviations from the allometry would suggest that other evolutionary processes contribute to explain the emergence of larger, lightweight-coated seeds in crops. Crops fitted the scaling slope but deviated from its intercept in a consistent way: Seed coats of crops were lighter than expected by their seed size. The wild progenitors of crops displayed the same trend, indicating that deviations cannot be solely attributed to artificial selection during or after domestication. The evolution of seeds with small coats in crops likely resulted from a combination of various pressures, including the selection of wild progenitors with coats smaller than other wild plants, further decreases during early evolution under cultivation, and indirect selection due to the seed coat-seed size allometry.


Assuntos
Evolução Biológica , Biomassa , Produtos Agrícolas , Sementes , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/anatomia & histologia , Produtos Agrícolas/fisiologia , Sementes/crescimento & desenvolvimento , Sementes/anatomia & histologia , Sementes/fisiologia
4.
Mol Cell ; 64(1): 148-162, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27642048

RESUMO

Mutations in subunits of mitochondrial m-AAA proteases in the inner membrane cause neurodegeneration in spinocerebellar ataxia (SCA28) and hereditary spastic paraplegia (HSP7). m-AAA proteases preserve mitochondrial proteostasis, mitochondrial morphology, and efficient OXPHOS activity, but the cause for neuronal loss in disease is unknown. We have determined the neuronal interactome of m-AAA proteases in mice and identified a complex with C2ORF47 (termed MAIP1), which counteracts cell death by regulating the assembly of the mitochondrial Ca2+ uniporter MCU. While MAIP1 assists biogenesis of the MCU subunit EMRE, the m-AAA protease degrades non-assembled EMRE and ensures efficient assembly of gatekeeper subunits with MCU. Loss of the m-AAA protease results in accumulation of constitutively active MCU-EMRE channels lacking gatekeeper subunits in neuronal mitochondria and facilitates mitochondrial Ca2+ overload, mitochondrial permeability transition pore opening, and neuronal death. Together, our results explain neuronal loss in m-AAA protease deficiency by deregulated mitochondrial Ca2+ homeostasis.


Assuntos
Canais de Cálcio/metabolismo , Cerebelo/metabolismo , Corpo Estriado/metabolismo , Hipocampo/metabolismo , Metaloendopeptidases/genética , Mitocôndrias/metabolismo , Neurônios/metabolismo , Proteases Dependentes de ATP/genética , Proteases Dependentes de ATP/metabolismo , ATPases Associadas a Diversas Atividades Celulares , Animais , Cálcio/metabolismo , Canais de Cálcio/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Morte Celular , Cerebelo/patologia , Corpo Estriado/patologia , Regulação da Expressão Gênica , Células HEK293 , Hipocampo/patologia , Homeostase/genética , Humanos , Transporte de Íons , Metaloendopeptidases/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/patologia , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Neurônios/patologia , Mapeamento de Interação de Proteínas , Transdução de Sinais
5.
Brain ; 145(7): 2602-2616, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35104841

RESUMO

Bi-allelic pathogenic variants in ZBTB11 have been associated with intellectual developmental disorder, autosomal recessive 69 (MRT69; OMIM 618383). We report five patients from three families with novel, bi-allelic variants in ZBTB11. We have expanded the clinical phenotype of MRT69, documenting varied severity of atrophy affecting different brain regions and described combined malonic and methylmalonic aciduria as a biochemical manifestation. As ZBTB11 encodes for a transcriptional regulator, we performeded chromatin immunoprecipitation-sequencing targeting ZBTB11 in fibroblasts from patients and controls. Chromatin immunoprecipitation-sequencing revealed binding of wild-type ZBTB11 to promoters in 238 genes, among which genes encoding proteins involved in mitochondrial functions and RNA processing are over-represented. Mutated ZBTB11 showed reduced binding to 61 of the targeted genes, indicating that the variants act as loss of function. Most of these genes are related to mitochondrial functions. Transcriptome analysis of the patient fibroblasts revealed dysregulation of mitochondrial functions. In addition, we uncovered that reduced binding of the mutated ZBTB11 to ACSF3 leads to decreased ACSF3 transcript level, explaining combined malonic and methylmalonic aciduria. Collectively, these results expand the clinical spectrum of ZBTB11-related neurological disease and give insight into the pathophysiology in which the dysfunctional ZBTB11 affect mitochondrial functions and RNA processing contributing to the neurological and biochemical phenotypes.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Erros Inatos do Metabolismo , Malformações do Sistema Nervoso , Erros Inatos do Metabolismo dos Aminoácidos/genética , Encéfalo , Humanos , Erros Inatos do Metabolismo/genética
6.
Am J Hum Genet ; 102(4): 685-695, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29576219

RESUMO

Biogenesis of the mitochondrial oxidative phosphorylation system, which produces the bulk of ATP for almost all eukaryotic cells, depends on the translation of 13 mtDNA-encoded polypeptides by mitochondria-specific ribosomes in the mitochondrial matrix. These mitoribosomes are dual-origin ribonucleoprotein complexes, which contain mtDNA-encoded rRNAs and tRNAs and ∼80 nucleus-encoded proteins. An increasing number of gene mutations that impair mitoribosomal function and result in multiple OXPHOS deficiencies are being linked to human mitochondrial diseases. Using exome sequencing in two unrelated subjects presenting with sensorineural hearing impairment, mild developmental delay, hypoglycemia, and a combined OXPHOS deficiency, we identified mutations in the gene encoding the mitochondrial ribosomal protein S2, which has not previously been implicated in disease. Characterization of subjects' fibroblasts revealed a decrease in the steady-state amounts of mutant MRPS2, and this decrease was shown by complexome profiling to prevent the assembly of the small mitoribosomal subunit. In turn, mitochondrial translation was inhibited, resulting in a combined OXPHOS deficiency detectable in subjects' muscle and liver biopsies as well as in cultured skin fibroblasts. Reintroduction of wild-type MRPS2 restored mitochondrial translation and OXPHOS assembly. The combination of lactic acidemia, hypoglycemia, and sensorineural hearing loss, especially in the presence of a combined OXPHOS deficiency, should raise suspicion for a ribosomal-subunit-related mitochondrial defect, and clinical recognition could allow for a targeted diagnostic approach. The identification of MRPS2 as an additional gene related to mitochondrial disease further expands the genetic and phenotypic spectra of OXPHOS deficiencies caused by impaired mitochondrial translation.


Assuntos
Alelos , Perda Auditiva Neurossensorial/genética , Hipoglicemia/genética , Doenças Mitocondriais/genética , Proteínas Mitocondriais/genética , Mutação/genética , Proteínas Ribossômicas/genética , Sequência de Aminoácidos , Pré-Escolar , Análise Mutacional de DNA , DNA Mitocondrial/genética , Feminino , Fibroblastos/metabolismo , Perda Auditiva Neurossensorial/complicações , Humanos , Hipoglicemia/complicações , Lactente , Recém-Nascido , Masculino , Doenças Mitocondriais/complicações , Proteínas Mitocondriais/química , Fosforilação Oxidativa , Subunidades Proteicas/genética , RNA Ribossômico/genética , Proteínas Ribossômicas/química
7.
Genet Med ; 23(9): 1705-1714, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34140661

RESUMO

PURPOSE: To investigate monoallelic CLPB variants. Pathogenic variants in many genes cause congenital neutropenia. While most patients exhibit isolated hematological involvement, biallelic CLPB variants underlie a neurological phenotype ranging from nonprogressive intellectual disability to prenatal encephalopathy with progressive brain atrophy, movement disorder, cataracts, 3-methylglutaconic aciduria, and neutropenia. CLPB was recently shown to be a mitochondrial refoldase; however, the exact function remains elusive. METHODS: We investigated six unrelated probands from four countries in three continents, with neutropenia and a phenotype dominated by epilepsy, developmental issues, and 3-methylglutaconic aciduria with next-generation sequencing. RESULTS: In each individual, we identified one of four different de novo monoallelic missense variants in CLPB. We show that these variants disturb refoldase and to a lesser extent ATPase activity of CLPB in a dominant-negative manner. Complexome profiling in fibroblasts showed CLPB at very high molecular mass comigrating with the prohibitins. In control fibroblasts, HAX1 migrated predominantly as monomer while in patient samples multiple HAX1 peaks were observed at higher molecular masses comigrating with CLPB thus suggesting a longer-lasting interaction between CLPB and HAX1. CONCLUSION: Both biallelic as well as specific monoallelic CLPB variants result in a phenotypic spectrum centered around neurodevelopmental delay, seizures, and neutropenia presumably mediated via HAX1.


Assuntos
Encefalopatias , Epilepsia , Deficiência Intelectual , Erros Inatos do Metabolismo , Neutropenia , Proteínas Adaptadoras de Transdução de Sinal , Humanos , Deficiência Intelectual/genética , Neutropenia/genética
8.
Amino Acids ; 53(9): 1431-1439, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34232398

RESUMO

The use of 2H2O in tank water to assess protein synthesis rates in fish is a relatively novel methodology that could allow for a better understanding of the effects of particular nutritional and environmental variables on rates of protein accretion. As such, this study involved an assessment and comparison of protein synthesis rates in the muscle of juvenile red drum fed a control diet (nutritionally complete) versus a valine (Val)-deficient diet. Six groups of 12 juvenile red drum, initially weighing ~ 4.5 g/fish, were stocked in six separate 38-L aquaria operating as a recirculating system. Fish were acclimatized to experimental conditions for 2 weeks while being fed the control diet. Just prior to initiating the protein synthesis assay, one aquarium of fish was fed the control diet while a second aquarium of fish was fed the Val-deficient diet. Immediately after consuming the experimental diets, each group of fish was moved to an independent aquarium containing 2H2O, and the fractional synthetic rate (FSR) of protein synthesis was obtained at 12, 24, 36 and 48 h after feeding by collecting two fish per treatment at each time point. This protein synthesis assay procedure was performed in three separate sessions, and considered as replicates over time (n = 3) for fish fed the control or Val-deficient diets immediately before initiating the session. Results indicated that a one-time feeding of a diet deficient in Val significantly reduced protein synthesis rates in the muscle of red drum. In addition, a significant effect of time after feeding was found, where observed FSR values peaked at 12 h after feeding and decreased as time progressed. In conclusion, deuterium methodologies were applicable to red drum, and this approach had the sensitivity to assess differences in protein synthesis rates when dietary perturbations were introduced.


Assuntos
Ração Animal/análise , Óxido de Deutério/química , Dieta , Suplementos Nutricionais , Proteínas Musculares/metabolismo , Músculos/metabolismo , Valina/deficiência , Animais , Perciformes
9.
Ann Hepatol ; 22: 100237, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32835861

RESUMO

Infected hepatic echinococcosis (IHE), defined as a cystic infection, and the development of a liver abscess may be a complication in the natural history of hepatic echinococcosis. The aim of this study was to review the evidence available related to clinical, therapeutic, and prognostic aspects of IHE. We conducted a systematic review. Trip Database, BIREME-BVS, SciELO, LILACS, IBECS, PAHO-WHO; WoS, EMBASE, SCOPUS and PubMed were consulted. Studies related to IHE in humans, without language restriction, published between 1966 and 2020 were considered. Variables studied were publication year, geographical origin of the samples, number of patients, therapeutic and prognosis aspects, and methodological quality (MQ) for each article. Descriptive statistics was applied. Subsequently, weighted averages (WA) of the MQ of each article were calculated for each variable of interest. 960 related articles were identified; 47 fulfilled selection criteria, including 486 patients with a median age of 48 years, 51.6% being male. The largest proportion of articles were from Spain, India, and Greece (36.1%). Mean cyst diameter was 14.1 cm, and main location was right liver lobe (74.0%). WA for morbidity, mortality, hospital stay, and follow-up were 28.5%, 7.4%, 8.5 days and 14.8 months, respectively. The most common causative microorganisms of superinfection isolated were Enterobacteriaceae. An association with cholangitis was reported in 13.4% of cases. Mean MQ of the 47 articles included was 7.6 points. We can conclude that the information related to IHE is scarce and scattered throughout articles of small casuistry and poor quality, and consequently does not provide strong evidence.


Assuntos
Equinococose Hepática/diagnóstico , Equinococose Hepática/terapia , Equinococose Hepática/mortalidade , Humanos , Prognóstico
10.
Am J Hum Genet ; 100(2): 216-227, 2017 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-28065471

RESUMO

Defects of the V-type proton (H+) ATPase (V-ATPase) impair acidification and intracellular trafficking of membrane-enclosed compartments, including secretory granules, endosomes, and lysosomes. Whole-exome sequencing in five families affected by mild to severe cutis laxa, dysmorphic facial features, and cardiopulmonary involvement identified biallelic missense mutations in ATP6V1E1 and ATP6V1A, which encode the E1 and A subunits, respectively, of the V1 domain of the heteromultimeric V-ATPase complex. Structural modeling indicated that all substitutions affect critical residues and inter- or intrasubunit interactions. Furthermore, complexome profiling, a method combining blue-native gel electrophoresis and liquid chromatography tandem mass spectrometry, showed that they disturb either the assembly or the stability of the V-ATPase complex. Protein glycosylation was variably affected. Abnormal vesicular trafficking was evidenced by delayed retrograde transport after brefeldin A treatment and abnormal swelling and fragmentation of the Golgi apparatus. In addition to showing reduced and fragmented elastic fibers, the histopathological hallmark of cutis laxa, transmission electron microscopy of the dermis also showed pronounced changes in the structure and organization of the collagen fibers. Our findings expand the clinical and molecular spectrum of metabolic cutis laxa syndromes and further link defective extracellular matrix assembly to faulty protein processing and cellular trafficking caused by genetic defects in the V-ATPase complex.


Assuntos
Cútis Laxa/genética , Mutação de Sentido Incorreto , ATPases Vacuolares Próton-Translocadoras/genética , Adolescente , Alelos , Sequência de Aminoácidos , Estudos de Casos e Controles , Criança , Feminino , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Glicosilação , Complexo de Golgi/metabolismo , Humanos , Lactente , Recém-Nascido , Masculino , Linhagem , Conformação Proteica , Transporte Proteico , Espectrometria de Massas em Tandem
11.
Bioinformatics ; 35(17): 3083-3091, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30649188

RESUMO

MOTIVATION: Complexome profiling combines native gel electrophoresis with mass spectrometry to obtain the inventory, composition and abundance of multiprotein assemblies in an organelle. Applying complexome profiling to determine the effect of a mutation on protein complexes requires separating technical and biological variations from the variations caused by that mutation. RESULTS: We have developed the COmplexome Profiling ALignment (COPAL) tool that aligns multiple complexome profiles with each other. It includes the abundance profiles of all proteins on two gels, using a multi-dimensional implementation of the dynamic time warping algorithm to align the gels. Subsequent progressive alignment allows us to align multiple profiles with each other. We tested COPAL on complexome profiles from control mitochondria and from Barth syndrome (BTHS) mitochondria, which have a mutation in tafazzin gene that is involved in remodeling the inner mitochondrial membrane phospholipid cardiolipin. By comparing the variation between BTHS mitochondria and controls with the variation among either, we assessed the effects of BTHS on the abundance profiles of individual proteins. Combining those profiles with gene set enrichment analysis allows detecting significantly affected protein complexes. Most of the significantly affected protein complexes are located in the inner mitochondrial membrane (mitochondrial contact site and cristae organizing system, prohibitins), or are attached to it (the large ribosomal subunit). AVAILABILITY AND IMPLEMENTATION: COPAL is written in python and is available from http://github.com/cmbi/copal. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Síndrome de Barth , Humanos , Espectrometria de Massas , Mitocôndrias , Proteínas Mitocondriais , Mutação
12.
J Inherit Metab Dis ; 43(6): 1382-1391, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32418222

RESUMO

Inherited cutis laxa, or inelastic, sagging skin is a genetic condition of premature and generalised connective tissue ageing, affecting various elastic components of the extracellular matrix. Several cutis laxa syndromes are inborn errors of metabolism and lead to severe neurological symptoms. In a patient with cutis laxa, a choreoathetoid movement disorder, dysmorphic features and intellectual disability we performed exome sequencing to elucidate the underlying genetic defect. We identified the amino acid substitution R275W in phosphatidylinositol 4-kinase type IIα, caused by a homozygous missense mutation in the PI4K2A gene. We used lipidomics, complexome profiling and functional studies to measure phosphatidylinositol 4-phosphate synthesis in the patient and evaluated PI4K2A deficient mice to define a novel metabolic disorder. The R275W residue, located on the surface of the protein, is involved in forming electrostatic interactions with the membrane. The catalytic activity of PI4K2A in patient fibroblasts was severely reduced and lipid mass spectrometry showed that particular acyl-chain pools of PI4P and PI(4,5)P2 were decreased. Phosphoinositide lipids play a major role in intracellular signalling and trafficking and regulate the balance between proliferation and apoptosis. Phosphatidylinositol 4-kinases such as PI4K2A mediate the first step in the main metabolic pathway that generates PI4P, PI(4,5)P2 and PI(3,4,5)P3 . Although neurologic involvement is common, cutis laxa has not been reported previously in metabolic defects affecting signalling. Here we describe a patient with a complex neurological phenotype, premature ageing and a mutation in PI4K2A, illustrating the importance of this enzyme in the generation of inositol lipids with particular acylation characteristics.


Assuntos
Cútis Laxa/genética , Antígenos de Histocompatibilidade Menor/genética , Mutação de Sentido Incorreto , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Pele/patologia , Sequência de Aminoácidos , Animais , Criança , Cútis Laxa/patologia , Feminino , Glicosilação , Homozigoto , Humanos , Camundongos , Camundongos Knockout , Linhagem , Fosfatidilinositóis/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/deficiência
13.
Hum Mol Genet ; 26(13): 2541-2550, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28449065

RESUMO

Perrault syndrome (PS) is a rare recessive disorder characterized by ovarian dysgenesis and sensorineural deafness. It is clinically and genetically heterogeneous, and previously mutations have been described in different genes, mostly related to mitochondrial proteostasis. We diagnosed three unrelated females with PS and set out to identify the underlying genetic cause using exome sequencing. We excluded mutations in the known PS genes, but identified a single homozygous mutation in the ERAL1 gene (c.707A > T; p.Asn236Ile). Since ERAL1 protein binds to the mitochondrial 12S rRNA and is involved in the assembly of the small mitochondrial ribosomal subunit, the identified variant represented a likely candidate. In silico analysis of a 3D model for ERAL1 suggested that the mutated residue hinders protein-substrate interactions, potentially affecting its function. On a molecular basis, PS skin fibroblasts had reduced ERAL1 protein levels. Complexome profiling of the cells showed an overall decrease in the levels of assembled small ribosomal subunit, indicating that the ERAL1 variant affects mitochondrial ribosome assembly. Moreover, levels of the 12S rRNA were reduced in the patients, and were rescued by lentiviral expression of wild type ERAL1. At the physiological level, mitochondrial respiration was markedly decreased in PS fibroblasts, confirming disturbed mitochondrial function. Finally, knockdown of the C. elegans ERAL1 homologue E02H1.2 almost completely blocked egg production in worms, mimicking the compromised fertility in PS-affected women. Our cross-species data in patient cells and worms support the hypothesis that mutations in ERAL1 can cause PS and are associated with changes in mitochondrial metabolism.


Assuntos
Proteínas de Ligação ao GTP/genética , Disgenesia Gonadal 46 XX/genética , Perda Auditiva Neurossensorial/genética , Proteínas de Ligação a RNA/genética , Sequência de Aminoácidos/genética , Animais , Caenorhabditis elegans/genética , Exoma , Feminino , Proteínas de Ligação ao GTP/metabolismo , Disgenesia Gonadal 46 XX/metabolismo , Perda Auditiva Neurossensorial/metabolismo , Homozigoto , Humanos , Mitocôndrias/genética , Proteínas Mitocondriais/metabolismo , Chaperonas Moleculares/metabolismo , Mutação , Mutação de Sentido Incorreto/genética , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Proteínas de Ligação a RNA/metabolismo , Sequenciamento do Exoma
14.
Am J Hum Genet ; 99(1): 208-16, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27374773

RESUMO

Mitochondrial complex I deficiency results in a plethora of often severe clinical phenotypes manifesting in early childhood. Here, we report on three complex-I-deficient adult subjects with relatively mild clinical symptoms, including isolated, progressive exercise-induced myalgia and exercise intolerance but with normal later development. Exome sequencing and targeted exome sequencing revealed compound-heterozygous mutations in TMEM126B, encoding a complex I assembly factor. Further biochemical analysis of subject fibroblasts revealed a severe complex I deficiency caused by defective assembly. Lentiviral complementation with the wild-type cDNA restored the complex I deficiency, demonstrating the pathogenic nature of these mutations. Further complexome analysis of one subject indicated that the complex I assembly defect occurred during assembly of its membrane module. Our results show that TMEM126B defects can lead to complex I deficiencies and, interestingly, that symptoms can occur only after exercise.


Assuntos
Complexo I de Transporte de Elétrons/deficiência , Proteínas de Membrana/genética , Doenças Mitocondriais/genética , Debilidade Muscular/genética , Mutação , Adolescente , Adulto , Criança , Complexo I de Transporte de Elétrons/genética , Exercício Físico , Exoma/genética , Teste de Complementação Genética , Heterozigoto , Humanos , Lactente , Masculino , Adulto Jovem
15.
Neurochem Res ; 44(2): 498-506, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30603981

RESUMO

Spinal cord injury (SCI) is a condition that puts the patient's life at risk in the acute phase and, during the chronic stage, results in permanent deficits in motor, sensory and autonomic functions. Isolated therapeutic strategies have not shown an effect on this condition. Therefore, this study aimed to evaluate the effects of electroacupuncture (EA) and curcumin, alone or combined, on the oxidative balance, motor function recovery and amount of preserved tissue following a traumatic SCI. Long-Evans rats were divided into five groups: SHAM, SCI, SCI + EA, SCI + Curcumin, and SCI + EA + Curcumin. Nitric oxide was significantly decreased in the Curcumin group; the EA, Curcumin and SCI + EA + Curcumin groups had significantly decreased hydroxyl radical and lipid peroxidation levels. Motor function recovery and the amount of preserved spinal cord tissue were significantly greater in the EA, Curcumin and EA + Curcumin groups. The results show that EA and Curcumin treatment alone or in combination decreased oxidative stress, improved functional motor recovery and increased the amount of preserved spinal cord tissue following a traumatic injury.


Assuntos
Eletroacupuntura , Estresse Oxidativo/efeitos dos fármacos , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/terapia , Animais , Curcumina/farmacologia , Modelos Animais de Doenças , Eletroacupuntura/métodos , Feminino , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos Long-Evans , Medula Espinal/efeitos dos fármacos , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/tratamento farmacológico
16.
Cochrane Database Syst Rev ; 12: CD008661, 2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31828767

RESUMO

BACKGROUND: People with schizophrenia have a range of different symptoms, including positive symptoms (hallucinations and delusions), negative symptoms (such as social withdrawal and lack of affect), and cognitive impairment. The standard medication for people with schizophrenia is antipsychotics. However, these medications may not be effective for all symptoms of schizophrenia, as cognitive and negative symptoms are usually hard to treat. Additional therapies or medications are available for the management of these symptoms. Modafinil, a wakefulness-promoting agent most frequently used in narcolepsy or shift work sleep disorder, is one intervention that is theorised to have an effect of these symptoms. OBJECTIVES: The primary objective of this review was to assess the effects of modafinil for people with schizophrenia or related disorders. SEARCH METHODS: On 27 April 2015, 24 May 2017, and 31 October 2019, we searched the Cochrane Schizophrenia Group's register of trials, which is based on regular searches of CENTRAL, MEDLINE, Embase, AMED, BIOSIS, CINAHL, PsycINFO, PubMed, and registries of clinical trials. There are no language, time, document type, or publication status limitations for the inclusion of records in the register. SELECTION CRITERIA: We selected all randomised controlled trials comparing modafinil with placebo or other treatments for people with schizophrenia or schizophrenia-spectrum disorders. DATA COLLECTION AND ANALYSIS: We independently extracted data from the included studies. We analysed dichotomous data using risk ratios (RR) and 95% confidence intervals (CI). We analysed continuous data using mean difference (MD) with a 95% CI. We used a random-effects model for the meta-analysis. We used GRADE to complete a 'Summary of findings' table and assessed risk of bias for the included studies. MAIN RESULTS: Eleven studies including a total of 422 participants contributed to data analyses. Most studies had a small population size (average 38 people per study) and were of short duration. We also detected a high risk of bias for selective outcome reporting in just under 50% of the trials. We therefore rated the overall methodological quality of the included studies as low. We considered seven main outcomes of interest: clinically important change in overall mental state, clinically important change in cognitive functioning, incidence of a clinically important adverse effect/event, clinically important change in global state, leaving the study early for any reason, clinically important change in quality of life, and hospital admission. All studies assessed the effects of adding modafinil to participants' usual antipsychotic treatment compared to adding placebo to usual antipsychotic treatment. Six studies found that adding modafinil to antipsychotic treatment may have little or no effect on overall mental state of people with schizophrenia, specifically the risk of worsening psychosis (RR 0.91, 95% CI 0.28 to 2.98; participants = 209; studies = 6, low-quality evidence). Regarding the effect of modafinil on cognitive function, the trials did not report clinically important change data, but one study reported endpoint scores on the MATRICS Consensus Cognitive Battery (MCCB): in this study we found no clear difference in scores between modafinil and placebo treatment groups (MD -3.10, 95% CI -10.9 to 4.7; participants = 48; studies = 1, very low-quality evidence). Only one study (N = 35) reported adverse effect/event data. In this study one serious adverse event occurred in each group (RR 0.84, 95% CI 0.06 to 12.42; participants = 35; studies = 1, very low-quality evidence). One study measured change in global state using the Clinical Global Impression - Improvement Scale. This study found that adding modafinil to antipsychotic treatment may have little or no effect on global state (RR 6.36, 95% CI 0.94 to 43.07, participants = 21; studies = 1, very low-quality evidence). Nine studies found that modafinil has no effect on numbers of participants leaving the study early (RR 1.26, 95% CI 0.63 to 2.52 participants = 357; studies = 9, moderate-quality evidence). None of the trials reported clinically important change in quality of life, but one study did report quality of life using endpoint scores on the Quality of Life Inventory, finding no clear difference between treatment groups (MD -0.2, 95% CI -1.18 to 0.78; participants = 20; studies = 1, very low-quality evidence). Finally, one study reported data for number of participants needing hospitalisation: one participant in each group was hospitalised (RR 0.84, 95% CI 0.06 to 12.42; participants = 35; studies = 1, very low-quality evidence). AUTHORS' CONCLUSIONS: Due to methodological issues, low sample size, and short duration of the clinical trials as well as high risk of bias for outcome reporting, most of the evidence available for this review is of very low or low quality. For results where quality is low or very low, we are uncertain or very uncertain if the effect estimates are true effects, limiting our conclusions. Specifically, we found that modafinil is no better or worse than placebo at preventing worsening of psychosis; however, we are uncertain about this result. We have more confidence that participants receiving modafinil are no more likely to leave a trial early than participants receiving placebo. However, we are very uncertain about the remaining equivocal results between modafinil and placebo for outcomes such as improvement in global state or cognitive function, incidence of adverse events, and changes in quality of life. More high-quality data are needed before firm conclusions regarding the effects of modafinil for people with schizophrenia or related disorders can be made.


Assuntos
Modafinila/uso terapêutico , Esquizofrenia/tratamento farmacológico , Promotores da Vigília/uso terapêutico , Antipsicóticos/uso terapêutico , Cognição/efeitos dos fármacos , Cognição/fisiologia , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Proc Natl Acad Sci U S A ; 112(18): 5685-90, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25902503

RESUMO

Mitochondrial proton-pumping NADH:ubiquinone oxidoreductase (respiratory complex I) comprises more than 40 polypeptides and contains eight canonical FeS clusters. The integration of subunits and insertion of cofactors into the nascent complex is a complicated multistep process that is aided by assembly factors. We show that the accessory NUMM subunit of complex I (human NDUFS6) harbors a Zn-binding site and resolve its position by X-ray crystallography. Chromosomal deletion of the NUMM gene or mutation of Zn-binding residues blocked a late step of complex I assembly. An accumulating assembly intermediate lacked accessory subunit N7BM (NDUFA12), whereas a paralog of this subunit, the assembly factor N7BML (NDUFAF2), was found firmly bound instead. EPR spectroscopic analysis and metal content determination after chromatographic purification of the assembly intermediate showed that NUMM is required for insertion or stabilization of FeS cluster N4.


Assuntos
Mitocôndrias/metabolismo , NADH Desidrogenase/química , Zinco/química , Sítios de Ligação , Simulação por Computador , Cristalografia por Raios X , Espectroscopia de Ressonância de Spin Eletrônica , Complexo I de Transporte de Elétrons/metabolismo , Eletroforese , Deleção de Genes , Humanos , Membranas Mitocondriais/metabolismo , Chaperonas Moleculares/química , Conformação Molecular , Mutagênese Sítio-Dirigida , Mutação , Ligação Proteica , Estrutura Terciária de Proteína , Proteômica , Espectrofotometria
19.
Molecules ; 23(10)2018 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-30241366

RESUMO

Scaffolds can be considered as one of the most promising treatments for bone tissue regeneration. Herein, blends of chitosan, poly(vinyl alcohol), and hydroxyapatite in different ratios were used to synthesize scaffolds via freeze-drying. Mechanical tests, FTIR, swelling and solubility degree, DSC, morphology, and cell viability were used as characterization techniques. Statistical significance of the experiments was determined using a two-way analysis of variance (ANOVA) with p < 0.05. Crosslinked and plasticized scaffolds absorbed five times more water than non-crosslinked and plasticized ones, which is an indicator of better hydrophilic features, as well as adequate resistance to water without detriment of the swelling potential. Indeed, the tested mechanical properties were notably higher for samples which were undergone to crosslinking and plasticized process. The presence of chitosan is determinant in pore formation and distribution which is an imperative for cell communication. Uniform pore size with diameters ranging from 142 to 519 µm were obtained, a range that has been described as optimal for bone tissue regeneration. Moreover, cytotoxicity was considered as negligible in the tested conditions, and viability indicates that the material might have potential as a bone regeneration system.


Assuntos
Desenvolvimento Ósseo/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Engenharia Tecidual , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Osso e Ossos/química , Proliferação de Células/efeitos dos fármacos , Quitosana/síntese química , Quitosana/química , Quitosana/uso terapêutico , Durapatita/síntese química , Durapatita/química , Durapatita/uso terapêutico , Humanos , Osteoblastos/efeitos dos fármacos , Álcool de Polivinil/síntese química , Álcool de Polivinil/química , Álcool de Polivinil/uso terapêutico
20.
Biochim Biophys Acta Bioenerg ; 1858(3): 208-217, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27988283

RESUMO

Mitochondrial complex I is the largest respiratory chain complex. Despite the enormous progress made studying its structure and function in recent years, potential regulatory roles of its accessory subunits remained largely unresolved. Complex I gene NDUFV3, which occurs in metazoa, contains an extra exon that is only present in vertebrates and thereby evolutionary even younger than the rest of the gene. Alternative splicing of this extra exon gives rise to a short NDUFV3-S and a long NDUFV3-L protein isoform. Complexome profiling revealed that the two NDUFV3 isoforms are constituents of the multi-subunit complex I. Further mass spectrometric analyses of complex I from different murine and bovine tissues showed a tissue-specific expression pattern of NDUFV3-S and NDUFV3-L. Hence, NDUFV3-S was identified as the only isoform in heart and skeletal muscle, whereas in liver, brain, and lung NDUFV3-L was expressed as the dominant isoform, together with NDUFV3-S present in all tissues analyzed. Thus, we identified NDUFV3 as the first out of 30 accessory subunits of complex I present in vertebrate- and tissue-specific isoforms. Interestingly, the tissue-specific expression pattern of NDUFV3-S and NDUFV3-L isoforms was paralleled by changes in kinetic parameters, especially the substrate affinity of complex I. This may indicate a regulatory role of the NDUFV3 isoforms in different vertebrate tissues.


Assuntos
Complexo I de Transporte de Elétrons/genética , Evolução Molecular , Mitocôndrias Cardíacas/genética , Isoformas de Proteínas/genética , Processamento Alternativo/genética , Sequência de Aminoácidos/genética , Animais , Bovinos , Complexo I de Transporte de Elétrons/química , Éxons/genética , Regulação da Expressão Gênica , Humanos , Camundongos , Mitocôndrias Cardíacas/química , Músculo Esquelético/química , Músculo Esquelético/metabolismo , Especificidade de Órgãos , Isoformas de Proteínas/química
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