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1.
FASEB J ; 35(9): e21864, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34423880

RESUMO

Resistance training (RT) dynamically alters the skeletal muscle nuclear DNA methylome. However, no study has examined if RT affects the mitochondrial DNA (mtDNA) methylome. Herein, ten older, Caucasian untrained males (65 ± 7 y.o.) performed six weeks of full-body RT (twice weekly). Body composition and knee extensor torque were assessed prior to and 72 h following the last RT session. Vastus lateralis (VL) biopsies were also obtained. VL DNA was subjected to reduced representation bisulfite sequencing providing excellent coverage across the ~16-kilobase mtDNA methylome (254 CpG sites). Biochemical assays were also performed, and older male data were compared to younger trained males (22 ± 2 y.o., n = 7, n = 6 Caucasian & n = 1 African American). RT increased whole-body lean tissue mass (p = .017), VL thickness (p = .012), and knee extensor torque (p = .029) in older males. RT also affected the mtDNA methylome, as 63% (159/254) of the CpG sites demonstrated reduced methylation (p < .05). Several mtDNA sites presented a more "youthful" signature in older males after RT in comparison to younger males. The 1.12 kilobase mtDNA D-loop/control region, which regulates replication and transcription, possessed enriched hypomethylation in older males following RT. Enhanced expression of mitochondrial H- and L-strand genes and complex III/IV protein levels were also observed (p < .05). While limited to a shorter-term intervention, this is the first evidence showing that RT alters the mtDNA methylome in skeletal muscle. Observed methylome alterations may enhance mitochondrial transcription, and RT evokes mitochondrial methylome profiles to mimic younger men. The significance of these findings relative to broader RT-induced epigenetic changes needs to be elucidated.


Assuntos
Envelhecimento , Metilação de DNA , DNA Mitocondrial/metabolismo , Epigenoma , Regulação da Expressão Gênica , Genes Mitocondriais/genética , Músculo Esquelético/metabolismo , Treinamento de Força , Idoso , Envelhecimento/genética , Envelhecimento/metabolismo , DNA Mitocondrial/genética , Humanos , Masculino , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/citologia , RNA Mensageiro/análise , RNA Mensageiro/genética , Adulto Jovem
2.
Nat Commun ; 12(1): 4769, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362905

RESUMO

Beyond its role in mitochondrial bioenergetics, Coenzyme Q (CoQ, ubiquinone) serves as a key membrane-embedded antioxidant throughout the cell. However, how CoQ is mobilized from its site of synthesis on the inner mitochondrial membrane to other sites of action remains a longstanding mystery. Here, using a combination of Saccharomyces cerevisiae genetics, biochemical fractionation, and lipid profiling, we identify two highly conserved but poorly characterized mitochondrial proteins, Ypl109c (Cqd1) and Ylr253w (Cqd2), that reciprocally affect this process. Loss of Cqd1 skews cellular CoQ distribution away from mitochondria, resulting in markedly enhanced resistance to oxidative stress caused by exogenous polyunsaturated fatty acids, whereas loss of Cqd2 promotes the opposite effects. The activities of both proteins rely on their atypical kinase/ATPase domains, which they share with Coq8-an essential auxiliary protein for CoQ biosynthesis. Overall, our results reveal protein machinery central to CoQ trafficking in yeast and lend insights into the broader interplay between mitochondria and the rest of the cell.


Assuntos
Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo , Antioxidantes/metabolismo , Lipídeos , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/metabolismo , Estresse Oxidativo , Fosfotransferases/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
3.
Int J Mol Sci ; 22(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34360775

RESUMO

Coupling glycolysis and mitochondrial tricarboxylic acid cycle, pyruvate dehydrogenase (PDH) complex (PDHC) is highly responsive to cellular demands through multiple mechanisms, including PDH phosphorylation. PDHC also produces acetyl-CoA for protein acetylation involved in circadian regulation of metabolism. Thiamine (vitamin B1) diphosphate (ThDP) is known to activate PDH as both coenzyme and inhibitor of the PDH inactivating kinases. Molecular mechanisms integrating the function of thiamine-dependent PDHC into general redox metabolism, underlie physiological fitness of a cell or an organism. Here, we characterize the daytime- and thiamine-dependent changes in the rat brain PDHC function, expression and phosphorylation, assessing their impact on protein acetylation and metabolic regulation. Morning administration of thiamine significantly downregulates both the PDH phosphorylation at Ser293 and SIRT3 protein level, the effects not observed upon the evening administration. This action of thiamine nullifies the daytime-dependent changes in the brain PDHC activity and mitochondrial acetylation, inducing diurnal difference in the cytosolic acetylation and acetylation of total brain proteins. Screening the daytime dependence of central metabolic enzymes and proteins of thiol/disulfide metabolism reveals that thiamine also cancels daily changes in the malate dehydrogenase activity, opposite to those of the PDHC activity. Correlation analysis indicates that thiamine abrogates the strong positive correlation between the total acetylation of the brain proteins and PDHC function. Simultaneously, thiamine heightens interplay between the expression of PDHC components and total acetylation or SIRT2 protein level. These thiamine effects on the brain acetylation system change metabolic impact of acetylation. The changes are exemplified by the thiamine enhancement of the SIRT2 correlations with metabolic enzymes and proteins of thiol-disulfide metabolism. Thus, we show the daytime- and thiamine-dependent changes in the function and phosphorylation of brain PDHC, contributing to regulation of the brain acetylation system and redox metabolism. The daytime-dependent action of thiamine on PDHC and SIRT3 may be of therapeutic significance in correcting perturbed diurnal regulation.


Assuntos
Encéfalo/metabolismo , Cetona Oxirredutases/metabolismo , Mitocôndrias/enzimologia , Proteínas Mitocondriais/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Sirtuínas/metabolismo , Tiamina/farmacologia , Acetilação/efeitos dos fármacos , Animais , Ciclo do Ácido Cítrico/efeitos dos fármacos , Masculino , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Fatores de Tempo
4.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34360841

RESUMO

Since their discovery, heat shock proteins (HSPs) have been identified in all domains of life, which demonstrates their importance and conserved functional role in maintaining protein homeostasis. Mitochondria possess several members of the major HSP sub-families that perform essential tasks for keeping the organelle in a fully functional and healthy state. In humans, the mitochondrial HSP70 chaperone system comprises a central molecular chaperone, mtHSP70 or mortalin (HSPA9), which is actively involved in stabilizing and importing nuclear gene products and in refolding mitochondrial precursor proteins, and three co-chaperones (HSP70-escort protein 1-HEP1, tumorous imaginal disc protein 1-TID-1, and Gro-P like protein E-GRPE), which regulate and accelerate its protein folding functions. In this review, we summarize the roles of mitochondrial molecular chaperones with particular focus on the human mtHsp70 and its co-chaperones, whose deregulated expression, mutations, and post-translational modifications are often considered to be the main cause of neurological disorders, genetic diseases, and malignant growth.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Doenças Neurodegenerativas/metabolismo , Proteínas de Choque Térmico HSP70/genética , Humanos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mutação , Neoplasias/genética , Doenças Neurodegenerativas/genética , Processamento de Proteína Pós-Traducional
5.
Int J Mol Sci ; 22(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361015

RESUMO

The sacred lotus (Nelumbo nucifera) can maintain a stable floral chamber temperature between 30 and 35 °C when blooming despite fluctuations in ambient temperatures between about 8 and 45 °C, but the regulatory mechanism of floral thermogenesis remains unclear. Here, we obtained comprehensive protein profiles from receptacle tissue at five developmental stages using data-independent acquisition (DIA)-based quantitative proteomics technology to reveal the molecular basis of floral thermogenesis of N. nucifera. A total of 6913 proteins were identified and quantified, of which 3513 differentially abundant proteins (DAPs) were screened. Among them, 640 highly abundant proteins during the thermogenic stages were mainly involved in carbon metabolism processes such as the tricarboxylic acid (TCA) cycle. Citrate synthase was identified as the most connected protein in the protein-protein interaction (PPI) network. Next, the content of alternative oxidase (AOX) and plant uncoupling protein (pUCP) in different tissues indicated that AOX was specifically abundant in the receptacles. Subsequently, a protein module highly related to the thermogenic phenotype was identified by the weighted gene co-expression network analysis (WGCNA). In summary, the regulation mechanism of floral thermogenesis in N. nucifera involves complex regulatory networks, including TCA cycle metabolism, starch and sucrose metabolism, fatty acid degradation, and ubiquinone synthesis, etc.


Assuntos
Adaptação Fisiológica , Flores/metabolismo , Redes Reguladoras de Genes , Nelumbo/genética , Mapas de Interação de Proteínas , Proteoma/metabolismo , Citrato (si)-Sintase/genética , Citrato (si)-Sintase/metabolismo , Ciclo do Ácido Cítrico , Flores/genética , Regulação da Expressão Gênica de Plantas , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Nelumbo/crescimento & desenvolvimento , Nelumbo/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteoma/genética , Temperatura
6.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34360857

RESUMO

Herein, for the first time, the potential relationships between the cytoskeleton-associated proteins DAAM1 and PREP with different testicular disorders, such as classic seminoma (CS), Leydig cell tumor (LCT), and Sertoli cell-only syndrome (SOS), were evaluated. Six CS, two LCT, and two SOS tissue samples were obtained during inguinal exploration in patients with a suspect testis tumor based on clinical examination and ultrasonography. DAAM1 and PREP protein levels and immunofluorescent localization were analyzed. An increased DAAM1 protein level in CS and SOS as compared to non-pathological (NP) tissue was observed, while LCT showed no significant differences. Conversely, PREP protein level increased in LCT, while it decreased in CS and SOS compared to NP tissue. These results were strongly supported by the immunofluorescence staining, revealing an altered localization and signal intensity of DAAM1 and PREP in the analyzed samples, highlighting a perturbed cytoarchitecture. Interestingly, in LCT spermatogonia, a specific DAAM1 nuclear localization was found, probably due to an enhanced testosterone production, as confirmed by the increased protein levels of steroidogenic enzymes. Finally, although further studies are needed to verify the involvement of other formins and microtubule-associated proteins, this report raised the opportunity to indicate DAAM1 and PREP as new potential markers, supporting the cytoskeleton dynamics changes occurring during normal and/or pathological cell differentiation.


Assuntos
Proteínas dos Microfilamentos/metabolismo , Proteínas Mitocondriais/metabolismo , Seminoma/metabolismo , Serina Endopeptidases/metabolismo , Neoplasias Testiculares/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Biomarcadores Tumorais/metabolismo , Citoesqueleto/metabolismo , Humanos , Masculino , Espermatogônias/metabolismo
7.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445477

RESUMO

Mitochondria-derived peptides (MDPs) are small peptides hidden in the mitochondrial DNA, maintaining mitochondrial function and protecting cells under different stresses. Currently, three types of MDPs have been identified: Humanin, MOTS-c and SHLP1-6. MDPs have demonstrated anti-apoptotic and anti-inflammatory activities, reactive oxygen species and oxidative stress-protecting properties both in vitro and in vivo. Recent research suggests that MDPs have a significant cardioprotective role, affecting CVDs (cardiovascular diseases) development and progression. CVDs are the leading cause of death globally; this term combines disorders of the blood vessels and heart. In this review, we focus on the recent progress in understanding the relationships between MDPs and the main cardiovascular risk factors (atherosclerosis, insulin resistance, hyperlipidaemia and ageing). We also will discuss the therapeutic application of MDPs, modified and synthetic MDPs, and their potential as novel biomarkers and therapeutic targets.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Fragmentos de Peptídeos/farmacologia , Animais , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Humanos
8.
Oxid Med Cell Longev ; 2021: 2989974, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34457111

RESUMO

In the present study, we used lipopolysaccharide- (LPS-) stimulated H9C2 cardiomyocytes to investigate whether irisin treatment attenuates septic cardiomyopathy via Fundc1-related mitophagy. Fundc1 levels and mitophagy were significantly reduced in LPS-stimulated H9C2 cardiomyocytes but were significantly increased by irisin treatment. Irisin significantly increased ATP production and the activities of mitochondrial complexes I and III in the LPS-stimulated cardiomyocytes. Irisin also improved glucose metabolism and significantly reduced LPS-induced levels of reactive oxygen species by increasing the activities of antioxidant enzymes, glutathione peroxidase (GPX), and superoxide dismutase (SOD), as well as levels of reduced glutathione (GSH). TUNEL assays showed that irisin significantly reduced LPS-stimulated cardiomyocyte apoptosis by suppressing the activation of caspase-3 and caspase-9. However, the beneficial effects of irisin on oxidative stress, mitochondrial metabolism, and viability of LPS-stimulated H9C2 cardiomyocytes were abolished by silencing Fundc1. These results demonstrate that irisin abrogates mitochondrial dysfunction, oxidative stress, and apoptosis through Fundc1-related mitophagy in LPS-stimulated H9C2 cardiomyocytes. This suggests irisin is a potentially useful treatment for septic cardiomyopathy, though further investigations are necessary to confirm our findings.


Assuntos
Apoptose , Cardiomiopatias/patologia , Fibronectinas/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/patologia , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/patologia , Estresse Oxidativo , Sepse/patologia , Animais , Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Células Cultivadas , Fibronectinas/genética , Proteínas de Membrana/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Mitofagia , Miócitos Cardíacos/metabolismo , Ratos , Sepse/etiologia , Sepse/metabolismo
9.
Int J Mol Sci ; 22(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361072

RESUMO

Mitochondria are energetic and dynamic organelles with a crucial role in bioenergetics, metabolism, and signaling. Mitochondrial proteins, encoded by both nuclear and mitochondrial DNA, must be properly regulated to ensure proteostasis. Mitochondrial protein quality control (MPQC) serves as a critical surveillance system, employing different pathways and regulators as cellular guardians to ensure mitochondrial protein quality and quantity. In this review, we describe key pathways and players in MPQC, such as mitochondrial protein translocation-associated degradation, mitochondrial stress responses, chaperones, and proteases, and how they work together to safeguard mitochondrial health and integrity. Deregulated MPQC leads to proteotoxicity and dysfunctional mitochondria, which contributes to numerous human diseases, including cancer. We discuss how alterations in MPQC components are linked to tumorigenesis, whether they act as drivers, suppressors, or both. Finally, we summarize recent advances that seek to target these alterations for the development of anti-cancer drugs.


Assuntos
Mitocôndrias/patologia , Proteínas Mitocondriais/metabolismo , Mitofagia , Neoplasias/patologia , Proteostase , Animais , Humanos , Neoplasias/etiologia , Neoplasias/metabolismo
10.
Int J Mol Sci ; 22(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34360597

RESUMO

Toxoplasma gondii is a protozoan parasite that causes toxoplasmosis and infects almost one-third of the global human population. A lack of effective drugs and vaccines and the emergence of drug resistant parasites highlight the need for the development of new drugs. The mitochondrial electron transport chain (ETC) is an essential pathway for energy metabolism and the survival of T. gondii. In apicomplexan parasites, malate:quinone oxidoreductase (MQO) is a monotopic membrane protein belonging to the ETC and a key member of the tricarboxylic acid cycle, and has recently been suggested to play a role in the fumarate cycle, which is required for the cytosolic purine salvage pathway. In T. gondii, a putative MQO (TgMQO) is expressed in tachyzoite and bradyzoite stages and is considered to be a potential drug target since its orthologue is not conserved in mammalian hosts. As a first step towards the evaluation of TgMQO as a drug target candidate, in this study, we developed a new expression system for TgMQO in FN102(DE3)TAO, a strain deficient in respiratory cytochromes and dependent on an alternative oxidase. This system allowed, for the first time, the expression and purification of a mitochondrial MQO family enzyme, which was used for steady-state kinetics and substrate specificity analyses. Ferulenol, the only known MQO inhibitor, also inhibited TgMQO at IC50 of 0.822 µM, and displayed different inhibition kinetics compared to Plasmodium falciparum MQO. Furthermore, our analysis indicated the presence of a third binding site for ferulenol that is distinct from the ubiquinone and malate sites.


Assuntos
Cumarínicos/metabolismo , Malatos/metabolismo , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Proteínas de Protozoários/metabolismo , Toxoplasma/enzimologia , Ubiquinona/metabolismo , Animais , Humanos , Proteínas Mitocondriais/genética , Oxirredutases/genética , Proteínas de Protozoários/genética , Especificidade por Substrato
11.
Nat Commun ; 12(1): 4900, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385433

RESUMO

Skeletal muscle subsarcolemmal mitochondria (SSM) and intermyofibrillar mitochondria subpopulations have distinct metabolic activity and sensitivity, though the mechanisms that localize SSM to peripheral areas of muscle fibers are poorly understood. A protein interaction study and complexome profiling identifies PERM1 interacts with the MICOS-MIB complex. Ablation of Perm1 in mice reduces muscle force, decreases mitochondrial membrane potential and complex I activity, and reduces the numbers of SSM in skeletal muscle. We demonstrate PERM1 interacts with the intracellular adaptor protein ankyrin B (ANKB) that connects the cytoskeleton to the plasma membrane. Moreover, we identify a C-terminal transmembrane helix that anchors PERM1 into the outer mitochondrial membrane. We conclude PERM1 functions in the MICOS-MIB complex and acts as an adapter to connect the mitochondria with the sarcolemma via ANKB.


Assuntos
Anquirinas/metabolismo , Mitocôndrias Musculares/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas Musculares/metabolismo , Sarcolema/metabolismo , Animais , Membrana Celular/metabolismo , Citoesqueleto/metabolismo , Potencial da Membrana Mitocondrial/genética , Potencial da Membrana Mitocondrial/fisiologia , Camundongos Knockout , Proteínas Mitocondriais/metabolismo , Proteínas Musculares/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia
12.
Nat Cell Biol ; 23(7): 684-691, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34253897

RESUMO

Members of the mammalian AlkB family are known to mediate nucleic acid demethylation1,2. ALKBH7, a mammalian AlkB homologue, localizes in mitochondria and affects metabolism3, but its function and mechanism of action are unknown. Here we report an approach to site-specifically detect N1-methyladenosine (m1A), N3-methylcytidine (m3C), N1-methylguanosine (m1G) and N2,N2-dimethylguanosine (m22G) modifications simultaneously within all cellular RNAs, and discovered that human ALKBH7 demethylates m22G and m1A within mitochondrial Ile and Leu1 pre-tRNA regions, respectively, in nascent polycistronic mitochondrial RNA4-6. We further show that ALKBH7 regulates the processing and structural dynamics of polycistronic mitochondrial RNAs. Depletion of ALKBH7 leads to increased polycistronic mitochondrial RNA processing, reduced steady-state mitochondria-encoded tRNA levels and protein translation, and notably decreased mitochondrial activity. Thus, we identify ALKBH7 as an RNA demethylase that controls nascent mitochondrial RNA processing and mitochondrial activity.


Assuntos
Enzimas AlkB/metabolismo , Mitocôndrias/enzimologia , Proteínas Mitocondriais/metabolismo , Processamento Pós-Transcricional do RNA , RNA Mitocondrial/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Enzimas AlkB/genética , Citidina/análogos & derivados , Citidina/metabolismo , Guanosina/análogos & derivados , Guanosina/metabolismo , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Biossíntese de Proteínas , RNA Mitocondrial/genética , RNA de Transferência/genética , RNA de Transferência/metabolismo
13.
Sci Rep ; 11(1): 14748, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285303

RESUMO

Candidemia caused by Candida spp. is a serious threat in hospital settings being a major cause of acquired infection and death and a possible contributor to Covid-19 mortality. Candidemia incidence has been rising worldwide following increases in fungicide-resistant pathogens highlighting the need for more effective antifungal agents with novel modes of action. The membrane-bound enzyme alternative oxidase (AOX) promotes fungicide resistance and is absent in humans making it a desirable therapeutic target. However, the lipophilic nature of the AOX substrate (ubiquinol-10) has hindered its kinetic characterisation in physiologically-relevant conditions. Here, we present the purification and expression of recombinant AOXs from C. albicans and C. auris in a self-assembled proteoliposome (PL) system. Kinetic parameters (Km and Vmax) with respect to ubiquinol-10 have been determined. The PL system has also been employed in dose-response assays with novel AOX inhibitors. Such information is critical for the future development of novel treatments for Candidemia.


Assuntos
Candida albicans/enzimologia , Farmacorresistência Fúngica , Proteínas Fúngicas/metabolismo , Lipossomos/metabolismo , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Antifúngicos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/genética , Cinética , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/genética , Oxirredutases/antagonistas & inibidores , Oxirredutases/genética , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
14.
Cell Death Dis ; 12(7): 711, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267182

RESUMO

Mitochondria are the main oxygen consumers in cells and as such are the primary organelle affected by hypoxia. All hypoxia pathology presumably derives from the initial mitochondrial dysfunction. An early event in hypoxic pathology in C. elegans is disruption of mitochondrial proteostasis with induction of the mitochondrial unfolded protein response (UPRmt) and mitochondrial protein aggregation. Here in C. elegans, we screen through RNAis and mutants that confer either strong resistance to hypoxic cell death or strong induction of the UPRmt to determine the relationship between hypoxic cell death, UPRmt activation, and hypoxia-induced mitochondrial protein aggregation (HIMPA). We find that resistance to hypoxic cell death invariantly mitigated HIMPA. We also find that UPRmt activation invariantly mitigated HIMPA. However, UPRmt activation was neither necessary nor sufficient for resistance to hypoxic death and vice versa. We conclude that UPRmt is not necessarily hypoxia protective against cell death but does protect from mitochondrial protein aggregation, one of the early hypoxic pathologies in C. elegans.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Resposta a Proteínas não Dobradas , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Hipóxia Celular , Mitocôndrias/genética , Mitocôndrias/patologia , Proteínas Mitocondriais/genética , Agregados Proteicos , Agregação Patológica de Proteínas
15.
Mol Biochem Parasitol ; 244: 111393, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34197864

RESUMO

Mitochondrial protein import depends on heterooligomeric translocases in the outer and inner membranes. Using import substrates consisting of various lengths of the N-terminal part of mitochondrial dihydrolipoamide dehydrogenase (LDH) fused to dihydrofolate reductase we present an in vivo analysis showing that in Trypanosoma brucei at least 96 aa of mature LDH are required to efficiently produce an import intermediate that spans both translocases. This is different to yeast, where around 50 aa are sufficient to achieve the same task and likely reflects the different arrangement and architecture of the trypanosomal mitochondrial translocases. Furthermore, we show that formation of the stuck import intermediate leads to a strong growth inhibition suggesting that, depending on the length of the LDH, the import channels in the translocases are quantitatively blocked.


Assuntos
Di-Hidrolipoamida Desidrogenase/genética , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Sistemas de Translocação de Proteínas/genética , Proteínas de Protozoários/genética , Tetra-Hidrofolato Desidrogenase/genética , Trypanosoma brucei brucei/genética , Sequência de Aminoácidos , Di-Hidrolipoamida Desidrogenase/metabolismo , Regulação da Expressão Gênica , Mitocôndrias/enzimologia , Proteínas Mitocondriais/metabolismo , Sistemas de Translocação de Proteínas/metabolismo , Transporte Proteico , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Especificidade da Espécie , Tetra-Hidrofolato Desidrogenase/metabolismo , Trypanosoma brucei brucei/enzimologia
16.
Nat Commun ; 12(1): 4371, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34272364

RESUMO

Metabolic programming and mitochondrial dynamics along with T cell differentiation affect T cell fate and memory development; however, how to control metabolic reprogramming and mitochondrial dynamics in T cell memory development is unclear. Here, we provide evidence that the SUMO protease SENP1 promotes T cell memory development via Sirt3 deSUMOylation. SENP1-Sirt3 signalling augments the deacetylase activity of Sirt3, promoting both OXPHOS and mitochondrial fusion. Mechanistically, SENP1 activates Sirt3 deacetylase activity in T cell mitochondria, leading to reduction of the acetylation of mitochondrial metalloprotease YME1L1. Consequently, deacetylation of YME1L1 suppresses its activity on OPA1 cleavage to facilitate mitochondrial fusion, which results in T cell survival and promotes T cell memory development. We also show that the glycolytic intermediate fructose-1,6-bisphosphate (FBP) as a negative regulator suppresses AMPK-mediated activation of the SENP1-Sirt3 axis and reduces memory development. Moreover, glucose limitation reduces FBP production and activates AMPK during T cell memory development. These data show that glucose limitation activates AMPK and the subsequent SENP1-Sirt3 signalling for T cell memory development.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Linfócitos T CD8-Positivos/imunologia , Cisteína Endopeptidases/metabolismo , Memória Imunológica , Mitocôndrias/metabolismo , Sirtuína 3/metabolismo , Linfócitos T/metabolismo , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Acetilação , Aloenxertos , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Neoplasias do Colo/imunologia , Frutosedifosfatos/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Glucose/deficiência , Memória Imunológica/genética , Metabolômica , Metaloendopeptidases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Mitocôndrias/genética , Mitocôndrias/ultraestrutura , Dinâmica Mitocondrial/genética , Proteínas Mitocondriais/metabolismo , Fosforilação Oxidativa , Sirtuína 3/antagonistas & inibidores , Sirtuína 3/genética , Sumoilação , Linfócitos T/imunologia
17.
Front Immunol ; 12: 673692, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305903

RESUMO

In a perspective entitled 'From plant survival under severe stress to anti-viral human defense' we raised and justified the hypothesis that transcript level profiles of justified target genes established from in vitro somatic embryogenesis (SE) induction in plants as a reference compared to virus-induced profiles can identify differential virus signatures that link to harmful reprogramming. A standard profile of selected genes named 'ReprogVirus' was proposed for in vitro-scanning of early virus-induced reprogramming in critical primary infected cells/tissues as target trait. For data collection, the 'ReprogVirus platform' was initiated. This initiative aims to identify in a common effort across scientific boundaries critical virus footprints from diverse virus origins and variants as a basis for anti-viral strategy design. This approach is open for validation and extension. In the present study, we initiated validation by experimental transcriptome data available in public domain combined with advancing plant wet lab research. We compared plant-adapted transcriptomes according to 'RegroVirus' complemented by alternative oxidase (AOX) genes during de novo programming under SE-inducing conditions with in vitro corona virus-induced transcriptome profiles. This approach enabled identifying a major complex trait for early de novo programming during SARS-CoV-2 infection, called 'CoV-MAC-TED'. It consists of unbalanced ROS/RNS levels, which are connected to increased aerobic fermentation that links to alpha-tubulin-based cell restructuration and progression of cell cycle. We conclude that anti-viral/anti-SARS-CoV-2 strategies need to rigorously target 'CoV-MAC-TED' in primary infected nose and mouth cells through prophylactic and very early therapeutic strategies. We also discuss potential strategies in the view of the beneficial role of AOX for resilient behavior in plants. Furthermore, following the general observation that ROS/RNS equilibration/redox homeostasis is of utmost importance at the very beginning of viral infection, we highlight that 'de-stressing' disease and social handling should be seen as essential part of anti-viral/anti-SARS-CoV-2 strategies.


Assuntos
Reprogramação Celular/genética , Herança Multifatorial/genética , SARS-CoV-2/patogenicidade , Acetilserotonina O-Metiltransferasa/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Ciclo Celular/genética , Bases de Dados Genéticas , Daucus carota/genética , Daucus carota/crescimento & desenvolvimento , Fermentação , Perfilação da Expressão Gênica , Humanos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tubulina (Proteína)/genética , Vírus/patogenicidade
18.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281194

RESUMO

Cockayne syndrome group A (CS-A) is a rare recessive progeroid disorder characterized by sun sensitivity and neurodevelopmental abnormalities. Cells derived from CS-A patients present as pathological hallmarks excessive oxidative stress, mitochondrial fragmentation and apoptosis associated with hyperactivation of the mitochondrial fission dynamin related protein 1 (DRP1). In this study, by using human cell models we further investigated the interplay between DRP1 and CSA and we determined whether pharmacological or genetic inhibition of DRP1 affects disease progression. Both reactive oxygen and nitrogen species are in excess in CS-A cells and when the mitochondrial translocation of DRP1 is inhibited a reduction of these species is observed together with a recovery of mitochondrial integrity and a significant decrease of apoptosis. This study indicates that the CSA-driven modulation of DRP1 pathway is key to control mitochondrial homeostasis and apoptosis and suggests DRP1 as a potential target in the treatment of CS patients.


Assuntos
Síndrome de Cockayne/metabolismo , Dinaminas/metabolismo , Mitocôndrias/metabolismo , Animais , Apoptose/genética , Linhagem Celular , Síndrome de Cockayne/fisiopatologia , Progressão da Doença , Dinaminas/genética , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/fisiologia , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo , Proteínas Mitocondriais/metabolismo , Modelos Biológicos , Estresse Oxidativo , Quinazolinonas/metabolismo , Quinazolinonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
19.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203866

RESUMO

Peroxisomes are ubiquitous membrane-bound organelles, and aberrant localisation of peroxisomal proteins contributes to the pathogenesis of several disorders. Many computational methods focus on assigning protein sequences to subcellular compartments, but there are no specific tools tailored for the sub-localisation (matrix vs. membrane) of peroxisome proteins. We present here In-Pero, a new method for predicting protein sub-peroxisomal cellular localisation. In-Pero combines standard machine learning approaches with recently proposed multi-dimensional deep-learning representations of the protein amino-acid sequence. It showed a classification accuracy above 0.9 in predicting peroxisomal matrix and membrane proteins. The method is trained and tested using a double cross-validation approach on a curated data set comprising 160 peroxisomal proteins with experimental evidence for sub-peroxisomal localisation. We further show that the proposed approach can be easily adapted (In-Mito) to the prediction of mitochondrial protein localisation obtaining performances for certain classes of proteins (matrix and inner-membrane) superior to existing tools.


Assuntos
Aprendizado Profundo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Peroxissomos/metabolismo , Software , Algoritmos , Sequência de Aminoácidos , Proteínas Mitocondriais/metabolismo , Transporte Proteico , Reprodutibilidade dos Testes
20.
Front Immunol ; 12: 673723, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34211468

RESUMO

Reprogramming of primary virus-infected cells is the critical step that turns viral attacks harmful to humans by initiating super-spreading at cell, organism and population levels. To develop early anti-viral therapies and proactive administration, it is important to understand the very first steps of this process. Plant somatic embryogenesis (SE) is the earliest and most studied model for de novo programming upon severe stress that, in contrast to virus attacks, promotes individual cell and organism survival. We argued that transcript level profiles of target genes established from in vitro SE induction as reference compared to virus-induced profiles can identify differential virus traits that link to harmful reprogramming. To validate this hypothesis, we selected a standard set of genes named 'ReprogVirus'. This approach was recently applied and published. It resulted in identifying 'CoV-MAC-TED', a complex trait that is promising to support combating SARS-CoV-2-induced cell reprogramming in primary infected nose and mouth cells. In this perspective, we aim to explain the rationale of our scientific approach. We are highlighting relevant background knowledge on SE, emphasize the role of alternative oxidase in plant reprogramming and resilience as a learning tool for designing human virus-defense strategies and, present the list of selected genes. As an outlook, we announce wider data collection in a 'ReprogVirus Platform' to support anti-viral strategy design through common efforts.


Assuntos
COVID-19/prevenção & controle , Técnicas de Reprogramação Celular/métodos , Técnicas de Embriogênese Somática de Plantas/métodos , SARS-CoV-2/genética , COVID-19/patologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica de Plantas/genética , Humanos , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Desenvolvimento Vegetal/genética , Proteínas de Plantas/metabolismo , Plantas/embriologia , Plantas/genética , Espécies Reativas de Oxigênio/metabolismo
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