RESUMEN
Lidamycin (LDM) has been confirmed to have a strong anti-pancreatic cancer effect and can affect the mitochondrial function of pancreatic cancer cells. Mitofusin-2 (Mfn2) is located in the outer membrane of mitochondria, and Mfn2 is currently believed to play a role in cancer inhibition in pancreatic cancer. In order to explore whether the anti-pancreatic cancer effect of LDM is related to Mfn2-mediated mitophagy, Bioinformatics and in vitro cell experiments are used for experimental research. The experimental results demonstrated that Mfn2 is correlated with mitochondrial autophagy in pancreatic cancer. Lidamycin can increase the expression of Mfn2 in pancreatic cancer and affect the process of EMT, affect the level of reactive oxygen species and mitochondrial membrane potential, and increase the expression of mitochondrial autophagy marker proteins BNIP3L and Beclin1. These results demonstrate that Mfn2 affects mitophagy in pancreatic cancer cells by regulating the expression of Mfn2.
Asunto(s)
GTP Fosfohidrolasas , Proteínas de la Membrana , Proteínas Mitocondriales , Mitofagia , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Mitofagia/efectos de los fármacos , GTP Fosfohidrolasas/metabolismo , GTP Fosfohidrolasas/genética , Línea Celular Tumoral , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Aminoglicósidos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Beclina-1/metabolismo , Beclina-1/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Supresoras de TumorRESUMEN
Aminoacyl-transfer RiboNucleic Acid synthetases (ARSs) are essential enzymes that catalyze the attachment of each amino acid to their cognate tRNAs. Mitochondrial ARSs (mtARSs), which ensure protein synthesis within the mitochondria, are encoded by nuclear genes and imported into the organelle after translation in the cytosol. The extensive use of next generation sequencing (NGS) has resulted in an increasing number of variants in mtARS genes being identified and associated with mitochondrial diseases. The similarities between yeast and human mitochondrial translation machineries make yeast a good model to quickly and efficiently evaluate the effect of variants in mtARS genes. Genetic screening of patients with a clinical suspicion of mitochondrial disorders through a customized gene panel of known disease-genes, including all genes encoding mtARSs, led to the identification of missense variants in WARS2, NARS2 and RARS2. Most of them were classified as Variant of Uncertain Significance. We exploited yeast models to assess the functional consequences of the variants found in these genes encoding mitochondrial tryptophanyl-tRNA, asparaginyl-tRNA, and arginyl-tRNA synthetases, respectively. Mitochondrial phenotypes such as oxidative growth, oxygen consumption rate, Cox2 steady-state level and mitochondrial protein synthesis were analyzed in yeast strains deleted in MSW1, SLM5, and MSR1 (the yeast orthologues of WARS2, NARS2 and RARS2, respectively), and expressing the wild type or the mutant alleles. Pathogenicity was confirmed for most variants, leading to their reclassification as Likely Pathogenic. Moreover, the beneficial effects observed after asparagine and arginine supplementation in the growth medium suggest them as a potential therapeutic approach.
Asunto(s)
Aminoacil-ARNt Sintetasas , Mitocondrias , Enfermedades Mitocondriales , Saccharomyces cerevisiae , Humanos , Aminoacil-ARNt Sintetasas/genética , Aminoacil-ARNt Sintetasas/metabolismo , Enfermedades Mitocondriales/genética , Saccharomyces cerevisiae/genética , Mitocondrias/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Mutación MissenseRESUMEN
Mitochondrial dysfunction is a pivotal event contributing to the development of ageing-related kidney disorders. Lon protease 1 (LONP1) has been reported to be responsible for ageing-related renal fibrosis; however, the underlying mechanism(s) of LONP1-driven kidney ageing with respect to mitochondrial disturbances remains to be further explored. The level of LONP1 was tested in the kidneys of aged humans and mice. Renal fibrosis and mitochondrial quality control were confirmed in the kidneys of aged mice. Effects of LONP1 silencing or overexpression on renal fibrosis and mitochondrial quality control were explored. In addition, N6-methyladenosine (m6A) modification and methyltransferase like 3 (METTL3) levels, the relationship between LONP1 and METTL3, and the impacts of METTL3 overexpression on mitochondrial functions were confirmed. Furthermore, the expression of insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) and the regulatory effects of IGF2BP2 on LONP1 were confirmed in vitro. LONP1 expression was reduced in the kidneys of aged humans and mice, accompanied by renal fibrosis and mitochondrial dysregulation. Overexpression of LONP1 alleviated renal fibrosis and maintained mitochondrial homeostasis, while silencing of LONP1 had the opposite effect. Impaired METTL3-m6A signalling contributed at least in part to ageing-induced LONP1 modification, reducing subsequent degradation in an IGF2BP2-dependent manner. Moreover, METTL3 overexpression alleviated proximal tubule cell injury, preserved mitochondrial stability, inhibited LONP1 degradation, and protected mitochondrial functions. LONP1 mediates mitochondrial function in kidney ageing and that targeting LONP1 may be a potential therapeutic strategy for improving ageing-related renal fibrosis.
Asunto(s)
Adenosina , Envejecimiento , Fibrosis , Homeostasis , Enfermedades Renales , Riñón , Metiltransferasas , Mitocondrias , Proteínas Mitocondriales , Proteínas de Unión al ARN , Mitocondrias/metabolismo , Animales , Metiltransferasas/metabolismo , Metiltransferasas/genética , Humanos , Envejecimiento/metabolismo , Ratones , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Riñón/patología , Riñón/metabolismo , Masculino , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Enfermedades Renales/etiología , Enfermedades Renales/genética , Proteasas ATP-Dependientes/metabolismo , Proteasas ATP-Dependientes/genética , Transducción de Señal , Ratones Endogámicos C57BLRESUMEN
Rationale: Parkin (an E3 ubiquitin protein ligase) is an important regulator of mitophagy. However, the role of Parkin in viral myocarditis (VMC) remains unclear. Methods: Coxsackievirus B3 (CVB3) infection was induced in mice to create VMC. Cardiac function and inflammatory response were evaluated by echocardiography, histological assessment, and molecular analyses. AAV9 (adeno-associated virus 9), transmission electron microscopy (TEM) and western blotting were used to investigate the mechanisms by which Parkin regulates mitophagy and cardiac inflammation. Results: Our data indicated that Parkin- and BNIP3 (BCL2 interacting protein 3 like)-mediated mitophagy was activated in VMC mice and neonatal rat cardiac myocytes (NRCMs) infected with CVB3, which blocked autophagic flux by inhibiting autophagosome-lysosome fusion. Parkin silencing aggravated mortality and accelerated the development of cardiac dysfunction in CVB3-treated mice. While silencing of Parkin did not significantly increase inflammatory response through activating NF-κB pathway and production of inflammatory cytokines post-VMC, the mitophagy activity were reduced, which stimulated the accumulation of damaged mitochondria. Moreover, Parkin silencing exacerbated VMC-induced apoptosis. We consistently found that Parkin knockdown disrupted mitophagy activity and inflammatory response in NRCMs. Conclusion: This study elucidated the important role of Parkin in maintaining cardiac function and inflammatory response by regulating mitophagy activity and the NF-κB pathway during acute VMC. Although the functional impact of mitophagy remains unclear, our findings suggest that Parkin silencing may accelerate VMC development.
Asunto(s)
Infecciones por Coxsackievirus , Mitofagia , Miocarditis , Miocitos Cardíacos , Ubiquitina-Proteína Ligasas , Animales , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Miocarditis/virología , Miocarditis/metabolismo , Ratones , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/virología , Infecciones por Coxsackievirus/metabolismo , Infecciones por Coxsackievirus/virología , Masculino , Ratas , Enterovirus Humano B/fisiología , Apoptosis , Modelos Animales de Enfermedad , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , FN-kappa B/metabolismo , Ratones Endogámicos BALB CRESUMEN
This study investigated the mechanism by which NR4A1 regulates mitochondrial fission factor (Mff)-related mitochondrial fission and FUN14 domain 1 (FUNDC1)-mediated mitophagy following cardiac ischemia-reperfusion injury(I/R). Our findings showed that the damage regulation was positively correlated with the pathological fission and pan-apoptosis of myocardial cell mitochondria. Compared with wild-type mice (WT), NR4A1-knockout mice exhibited resistance to myocardial ischemia-reperfusion injury and mitochondrial pathological fission, characterized by mitophagy activation. Results showed that ischemia-reperfusion injury increased NR4A1 expression level, activating mitochondrial fission mediated by Mff and restoring the mitophagy phenotype mediated by FUNDC1. The inactivation of FUNDC1 phosphorylation could not mediate the normalization of mitophagy in a timely manner, leading to an excessive stress response of unfolded mitochondrial proteins and an imbalance in mitochondrial homeostasis. This process disrupted the normalization of the mitochondrial quality control network, leading to accumulation of damaged mitochondria and the activation of pan-apoptotic programs. Our data indicate that NR4A1 is a novel and critical target in myocardial I/R injury that exertsand negative regulatory effects by activating Mff-mediated mito-fission and inhibiting FUNDC1-mediated mitophagy. Targeting the crosstalk balance between NR4A1-Mff-FUNDC1 is a potential approach for treating I/R.
Asunto(s)
Ratones Noqueados , Dinámicas Mitocondriales , Proteínas Mitocondriales , Mitofagia , Daño por Reperfusión Miocárdica , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares , Animales , Daño por Reperfusión Miocárdica/metabolismo , Ratones , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Masculino , Ratones Endogámicos C57BL , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Mitocondrias/metabolismo , Apoptosis , Mitocondrias Cardíacas/metabolismoRESUMEN
The alternative oxidase (AOX), a common terminal oxidase in the electron transfer chain (ETC) of plants, plays a crucial role in stress resilience and plant growth and development. Oat (Avena sativa), an important crop with high nutritional value, has not been comprehensively studied regarding the AsAOX gene family. Therefore, this study explored the responses and potential functions of the AsAOX gene family to various abiotic stresses and their potential evolutionary pathways. Additionally, we conducted a genome-wide analysis to explore the evolutionary conservation and divergence of AOX gene families among three Avena species (Avena sativa, Avena insularis, Avena longiglumis) and four Poaceae species (Avena sativa, Oryza sativa, Triticum aestivum, and Brachypodium distachyon). We identified 12 AsAOX, 9 AiAOX, and 4 AlAOX gene family members. Phylogenetic, motif, domain, gene structure, and selective pressure analyses revealed that most AsAOXs, AiAOXs, and AlAOXs are evolutionarily conserved. We also identified 16 AsAOX segmental duplication pairs, suggesting that segmental duplication may have contributed to the expansion of the AsAOX gene family, potentially preserving these genes through subfunctionalization. Chromosome polyploidization, gene structural variations, and gene fragment recombination likely contributed to the evolution and expansion of the AsAOX gene family as well. Additionally, we hypothesize that AsAOX2 may have potential function in resisting wounding and heat stresses, while AsAOX4 could be specifically involved in mitigating wounding stress. AsAOX11 might contribute to resistance against chromium and waterlogging stresses. AsAOX8 may have potential fuction in mitigating ABA-mediated stress. AsAOX12 and AsAOX5 are most likely to have potential function in mitigating salt and drought stresses, respectively. This study elucidates the potential evolutionary pathways of the AsAOXs gene family, explores their responses and potential functions to various abiotic stresses, identifies potential candidate genes for future functional studies, and facilitates molecular breeding applications in A. sativa.
Asunto(s)
Avena , Evolución Molecular , Proteínas Mitocondriales , Familia de Multigenes , Oxidorreductasas , Filogenia , Proteínas de Plantas , Estrés Fisiológico , Avena/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Triticum/genética , Triticum/enzimología , Duplicación de GenRESUMEN
Mitochondrial damage is an early and key marker of neuronal damage in prion diseases. As a process involved in mitochondrial quality control, mitochondrial biogenesis regulates mitochondrial homeostasis in neurons and promotes neuron health by increasing the number of effective mitochondria in the cytoplasm. Sirtuin 1 (SIRT1) is a NAD+-dependent deacetylase that regulates neuronal mitochondrial biogenesis and quality control in neurodegenerative diseases via deacetylation of a variety of substrates. In a cellular model of prion diseases, we found that both SIRT1 protein levels and deacetylase activity decreased, and SIRT1 overexpression and activation significantly ameliorated mitochondrial morphological damage and dysfunction caused by the neurotoxic peptide PrP106-126. Moreover, we found that mitochondrial biogenesis was impaired, and SIRT1 overexpression and activation alleviated PrP106-126-induced impairment of mitochondrial biogenesis in N2a cells. Further studies in PrP106-126-treated N2a cells revealed that SIRT1 regulates mitochondrial biogenesis through the PGC-1α-TFAM pathway. Finally, we showed that resveratrol resolved PrP106-126-induced mitochondrial dysfunction and cell apoptosis by promoting mitochondrial biogenesis through activation of the SIRT1-dependent PGC-1α/TFAM signaling pathway in N2a cells. Taken together, our findings further describe SIRT1 regulation of mitochondrial biogenesis and improve our understanding of mitochondria-related pathogenesis in prion diseases. Our findings support further investigation of SIRT1 as a potential target for therapeutic intervention of prion diseases.
Asunto(s)
Mitocondrias , Biogénesis de Organelos , Fragmentos de Péptidos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Priones , Sirtuina 1 , Sirtuina 1/metabolismo , Sirtuina 1/genética , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Priones/metabolismo , Animales , Ratones , Fragmentos de Péptidos/metabolismo , Resveratrol/farmacología , Factores de Transcripción/metabolismo , Transducción de Señal/efectos de los fármacos , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genéticaRESUMEN
OBJECTIVES: Alcohol and its metabolites, such as acetaldehyde, induced hepatic mitochondrial dysfunction play a pathological role in the development of alcohol-related liver disease (ALD). METHODS: In this study, we investigated the potential of nobiletin (NOB), a polymethoxylated flavone, to counter alcohol-induced mitochondrial dysfunction and liver injury. RESULTS: Our findings demonstrate that NOB administration markedly attenuated alcohol-induced hepatic steatosis, endoplasmic reticulum stress, inflammation, and tissue damage in mice. NOB reversed hepatic mitochondrial dysfunction and oxidative stress in both alcohol-fed mice and acetaldehyde-treated hepatocytes. Mechanistically, NOB restored the reduction of hepatic mitochondrial transcription factor A (TFAM) at both mRNA and protein levels. Notably, the protective effects of NOB against acetaldehyde-induced mitochondrial dysfunction and cell death were abolished in hepatocytes lacking Tfam. Furthermore, NOB administration reinstated the levels of hepatocellular NRF1, a key transcriptional regulator of TFAM, which were decreased by alcohol and acetaldehyde exposure. Consistent with these findings, hepatocyte-specific overexpression of Nrf1 protected against alcohol-induced hepatic Tfam reduction, mitochondrial dysfunction, oxidative stress, and liver injury. CONCLUSIONS: Our study elucidates the involvement of the NRF1-TFAM signaling pathway in the protective mechanism of NOB against chronic-plus-binge alcohol consumption-induced mitochondrial dysfunction and liver injury, suggesting NOB supplementation as a potential therapeutic strategy for ALD.
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Flavonas , Transducción de Señal , Animales , Ratones , Flavonas/farmacología , Transducción de Señal/efectos de los fármacos , Masculino , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Estrés Oxidativo/efectos de los fármacos , Ratones Endogámicos C57BL , Hígado/efectos de los fármacos , Hígado/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Etanol/toxicidad , Etanol/efectos adversos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Hepatopatías Alcohólicas/metabolismo , Hepatopatías Alcohólicas/tratamiento farmacológico , Hepatopatías Alcohólicas/prevención & control , Hepatopatías Alcohólicas/patología , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Factor Nuclear 1 de Respiración/metabolismo , Factor Nuclear 1 de Respiración/genética , Sustancias Protectoras/farmacología , Factor 1 Relacionado con NF-E2/metabolismo , Factor 1 Relacionado con NF-E2/genética , Proteínas del Grupo de Alta MovilidadRESUMEN
Over 50 billion cells undergo apoptosis each day in an adult human to maintain tissue homeostasis by eliminating damaged or unwanted cells. Apoptotic deficiency can lead to age-related diseases with reduced apoptotic metabolites. However, whether apoptotic metabolism regulates aging is unclear. Here, we show that aging mice and apoptosis-deficient MRL/lpr (B6.MRL-Faslpr/J) mice exhibit decreased apoptotic levels along with increased aging phenotypes in the skeletal bones, which can be rescued by the treatment with apoptosis inducer staurosporine (STS) and stem cell-derived apoptotic vesicles (apoVs). Moreover, embryonic stem cells (ESC)-apoVs can significantly reduce senescent hallmarks and mtDNA leakage to rejuvenate aging bone marrow mesenchymal stem cells (MSCs) and ameliorate senile osteoporosis when compared to MSC-apoVs. Mechanistically, ESC-apoVs use TCOF1 to upregulate mitochondrial protein transcription, resulting in FLVCR1-mediated mitochondrial functional homeostasis. Taken together, this study reveals a previously unknown role of apoptotic metabolites in ameliorating bone aging phenotypes and the unique role of TCOF1/FLVCR1 in maintaining mitochondrial homeostasis.
Asunto(s)
Envejecimiento , Apoptosis , Homeostasis , Células Madre Mesenquimatosas , Mitocondrias , Animales , Humanos , Ratones , Envejecimiento/metabolismo , Apoptosis/efectos de los fármacos , Huesos/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Proteínas de Transporte de Membrana/genética , Células Madre Mesenquimatosas/metabolismo , Ratones Endogámicos C57BL , Ratones Endogámicos MRL lpr , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Osteoporosis/metabolismo , Fenotipo , Estaurosporina/farmacologíaRESUMEN
The mitochondrial enzyme methylenetetrahydrofolate dehydrogenase (MTHFD2) is involved in purine and thymidine synthesis via 1C metabolism. MTHFD2 is exclusively overexpressed in cancer cells but absent in most healthy adult human tissues. However, the two close homologs of MTHFD2 known as MTHFD1 and MTHFD2L are expressed in healthy adult human tissues and share a great structural resemblance to MTHFD2 with 54% and 89% sequence similarity, respectively. It is therefore notably challenging to find selective inhibitors of MTHFD2 due to the structural similarity, in particular protein binding site similarity with MTHFD1 and MTHFD2L. Tricyclic coumarin-based compounds (substrate site binders) and xanthine derivatives (allosteric site binders) are the only selective inhibitors of MTHFD2 reported till date. Nanomolar potent diaminopyrimidine-based inhibitors of MTHFD2 have been reported recently, however, they also demonstrate significant inhibitory activities against MTHFD1 and MTHFD2L. In this study, we have employed extensive computational modeling involving molecular docking and molecular dynamics simulations in order to investigate the binding modes and key interactions of diaminopyrimidine-based inhibitors at the substrate binding sites of MTHFD1, MTHFD2 and MTHFD2L, and compare with the tricyclic coumarin-based selective MTHFD2 inhibitor. The outcomes of our study provide significant insights into desirable and undesirable structural elements for rational structure-based design of new and selective inhibitors of MTHFD2 against cancer.
Asunto(s)
Aminohidrolasas , Inhibidores Enzimáticos , Metilenotetrahidrofolato Deshidrogenasa (NADP) , Antígenos de Histocompatibilidad Menor , Enzimas Multifuncionales , Metilenotetrahidrofolato Deshidrogenasa (NADP)/genética , Metilenotetrahidrofolato Deshidrogenasa (NADP)/antagonistas & inhibidores , Metilenotetrahidrofolato Deshidrogenasa (NADP)/metabolismo , Metilenotetrahidrofolato Deshidrogenasa (NADP)/química , Humanos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Antígenos de Histocompatibilidad Menor/genética , Antígenos de Histocompatibilidad Menor/metabolismo , Antígenos de Histocompatibilidad Menor/química , Enzimas Multifuncionales/genética , Enzimas Multifuncionales/antagonistas & inhibidores , Enzimas Multifuncionales/metabolismo , Enzimas Multifuncionales/química , Aminohidrolasas/genética , Aminohidrolasas/metabolismo , Aminohidrolasas/antagonistas & inhibidores , Aminohidrolasas/química , Pirimidinas/farmacología , Pirimidinas/química , Simulación del Acoplamiento Molecular , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/química , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/antagonistas & inhibidores , Sitios de Unión , Unión ProteicaRESUMEN
Insulin-like growth factor-1-induced activation of ATP citrate lyase (ACLY) improves muscle mitochondrial function through an Akt-dependent mechanism. In this study, we examined whether Akt1 deficiency alters skeletal muscle fiber type and mitochondrial function by regulating ACLY-dependent signaling in male Akt1 knockout (KO) mice (12-16 weeks old). Akt1 KO mice exhibited decreased body weight and muscle wet weight, with reduced cross-sectional areas of slow- and fast-type muscle fibers. Loss of Akt1 did not affect the phosphorylation status of ACLY in skeletal muscle. The skeletal muscle fiber type and expression of mitochondrial oxidative phosphorylation complex proteins were unchanged in Akt1 KO mice compared with the wild-type control. These observations indicate that Akt1 is important for the regulation of skeletal muscle fiber size, whereas the regulation of muscle fiber type and muscle mitochondrial content occurs independently of Akt1 activity.
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Ratones Noqueados , Proteínas Proto-Oncogénicas c-akt , Animales , Masculino , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Ratones , Músculo Esquelético/metabolismo , Mitocondrias Musculares/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/deficiencia , Ratones Endogámicos C57BL , Fibras Musculares Esqueléticas/metabolismo , ATP Citrato (pro-S)-Liasa/metabolismo , ATP Citrato (pro-S)-Liasa/genética , ATP Citrato (pro-S)-Liasa/deficienciaRESUMEN
Hepatocellular carcinoma (HCC) is a common and lethal liver cancer characterized by complex aetiology and limited treatment options. FAM210B, implicated in various cancers, is noteworthy for its potential role in the progression and treatment response of HCC. Yet, its expression patterns, functional impacts and correlations with patient outcomes and resistance to therapy are not well understood. We employed a comprehensive methodology to explore the role of FAM210B in HCC, analysing its expression across cancers, subcellular localization and impacts on cell proliferation, invasion, migration, biological enrichment and the immune microenvironment. Additionally, we investigated its expression in single cells, drug sensitivity and relationships with genomic instability, immunotherapy efficacy and key immune checkpoints. While FAM210B expression varied across cancers, there was no notable difference between HCC and normal tissues. Elevated levels of FAM210B were associated with improved survival outcomes. Subcellular analysis located FAM210B in the plasma membrane and cytosol. FAM210B was generally downregulated in HCC, and its suppression significantly enhanced cell proliferation, invasion and migration. Biological enrichment analysis linked FAM210B to metabolic and immune response pathways. Moreover, its expression modified the immune microenvironment of HCC, affecting drug responsiveness and immunotherapy outcomes. High expression levels of FAM202B correlated with increased resistance to sunitinib and enhanced responsiveness to immunotherapy, as evidenced by associations with tumour mutation burden, PDCD1, CTLA4 and TIDE scores. FAM210B exerts a complex influence on HCC, affecting tumour cell behaviour, metabolic pathways, the immune microenvironment and responses to therapy.
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Carcinoma Hepatocelular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas , Proteínas de la Membrana , Proteínas Mitocondriales , Microambiente Tumoral , Humanos , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Movimiento Celular , Progresión de la Enfermedad , Resistencia a Antineoplásicos/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Microambiente Tumoral/genética , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismoRESUMEN
The conversion of nitrate to ammonium, i.e., nitrate reduction, is a major consumer of reductants in plants. Previous studies have reported that the mitochondrial alternative oxidase (AOX) is upregulated under limited nitrate reduction conditions, including no/low nitrate or when ammonium is the sole nitrogen (N) source. Electron transfer from ubiquinone to AOX bypasses the proton-pumping complexes III and IV, thereby consuming reductants efficiently. Thus, upregulated AOX under limited nitrate reduction may dissipate excessive reductants and thereby attenuate oxidative stress. Nevertheless, so far there is no firm evidence for this hypothesis due to the lack of experimental systems to analyze the direct relationship between nitrate reduction and AOX. We therefore developed a novel culturing system for A. thaliana that manipulates shoot activities of nitrate reduction and AOX separately without causing N starvation, ammonium toxicity, or lack of nitrate signal. Using shoots processed with this system, we examined genome-wide gene expression and growth to better understand the relationship between AOX and nitrate reduction. The results showed that, only when nitrate reduction was limited, AOX deficiency significantly upregulated genes involved in mitochondrial oxidative stress, reductant shuttles, and non-phosphorylating bypasses of the respiratory chain, and inhibited growth. Thus, we conclude that AOX alleviates mitochondrial oxidative stress and sustains plant growth under limited nitrate reduction.
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Arabidopsis , Mitocondrias , Proteínas Mitocondriales , Nitratos , Oxidación-Reducción , Estrés Oxidativo , Oxidorreductasas , Proteínas de Plantas , Arabidopsis/genética , Arabidopsis/metabolismo , Nitratos/metabolismo , Oxidorreductasas/metabolismo , Oxidorreductasas/genética , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Mitocondrias/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulación de la Expresión Génica de las Plantas , Compuestos de Amonio/metabolismoRESUMEN
BACKGROUND: Mitochondrial dysfunction and metabolic reprogramming can lead to the development and progression of hepatocellular carcinoma (HCC). Ferredoxin 1 (FDX1) is a small mitochondrial protein and recent studies have shown that FDX1 plays an important role in tumor cuproptosis, but its role in HCC is still elusive. In this study, we aim to investigate the expression and novel functions of FDX1 in HCC. METHODS: FDX1 expression was first analyzed in publicly available datasets and verified by immunohistochemistry, qRT-PCR and Western blot. In vitro and in vivo experiments were applied to explore the functions of FDX1. Non-targeted metabolomics and RNA-sequencing were used to determine molecular mechanism. mRFP-GFP-LC3 lentivirus transfection, Mito-Tracker Red and Lyso-Tracker Green staining, transmission electron microscopy, flow cytometry, JC-1 staining, etc. were used to analyze mitophagy or ROS levels. Hydrodynamic tail vein injection (HTVi) and patient-derived organoid (PDO) models were used to analyze effect of FDX1 overexpression. RESULTS: FDX1 expression is significantly downregulated in HCC tissues. FDX1 downregulation promotes HCC cell proliferation, invasion in vitro and growth, metastasis in vivo. In addition, FDX1 affects metabolism of HCC cells and is associated with autophagy. We then confirmed that FDX1 deficiency increases ROS levels, activates mitophagy and the PI3K/AKT signaling pathway in HCC cells. Interestingly, scavenging ROS attenuates the tumor-promoting role and mitophagy of FDX1 downregulation. The results of HTVi and PDO models both find that FDX1 elevation significantly inhibits HCC progression. Moreover, low FDX1 expression is associated with shorter survival and is an independent risk factor for prognosis in HCC patients. CONCLUSIONS: Our research had investigated novel functions of FDX1 in HCC. Downregulation of FDX1 contributes to metabolic reprogramming and leads to ROS-mediated activation of mitophagy and the PI3K/AKT signaling pathway. FDX1 is a potential prognostic biomarker and increasing FDX1 expression may be a potential therapeutic approach to inhibit HCC progression.
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Carcinoma Hepatocelular , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas , Mitofagia , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Especies Reactivas de Oxígeno , Transducción de Señal , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/genética , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Mitofagia/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Ratones , Animales , Línea Celular Tumoral , Proliferación Celular , Progresión de la Enfermedad , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Regulación hacia Abajo , Mitocondrias/metabolismo , Mitocondrias/genética , MasculinoRESUMEN
Adrenal tumors, such as adrenocortical carcinoma (ACC), adrenocortical adenoma (ACA), and pheochromocytoma (PCC) are complex diseases with unclear causes and treatments. Mitochondria and mitochondrial-derived peptides (MDPs) are crucial for cancer cell survival. The primary aim of this study was to analyze samples from different adrenal diseases, adrenocortical carcinoma, adrenocortical adenoma, and pheochromocytoma, and compare them with normal adrenal tissue to determine whether the expression levels of the mitochondrial open reading frame of the 12S rRNA type-c (MOTS-c) gene and protein vary between different types of adrenal tumors compared to healthy controls using qPCR, ELISA, and IHC methods. Results showed decreased MOTS-c mRNA expression in all adrenal tumors compared to controls, while serum MOTS-c protein levels increased in ACA and PCC but not in ACC. The local distribution of MOTS-c protein in adrenal tissue was reduced in all tumors. Notably, MOTS-c protein expression declined with ACC progression (stages III and IV) but was unrelated to patient age or sex. Tumor size and testosterone levels positively correlated with MOTS-c mRNA but negatively with serum MOTS-c protein. Additionally, serum MOTS-c protein correlated positively with glucose, total cholesterol, HDL, LDL, and SHGB levels. These findings suggest disrupted expression of MOTS-c in the spectrum of adrenal diseases, which might be caused by mechanisms involving increased mitochondrial dysfunction and structural changes in the tissue associated with disease progression. This study provides a detailed examination of MOTS-c mRNA and protein in adrenal tumors, indicating the potential role of MDPs in tumor biology and progression.
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Neoplasias de las Glándulas Suprarrenales , Feocromocitoma , Humanos , Masculino , Femenino , Persona de Mediana Edad , Neoplasias de las Glándulas Suprarrenales/genética , Neoplasias de las Glándulas Suprarrenales/metabolismo , Neoplasias de las Glándulas Suprarrenales/patología , Neoplasias de las Glándulas Suprarrenales/sangre , Adulto , Feocromocitoma/genética , Feocromocitoma/metabolismo , Feocromocitoma/patología , Feocromocitoma/sangre , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Regulación Neoplásica de la Expresión Génica , Anciano , Adenoma Corticosuprarrenal/genética , Adenoma Corticosuprarrenal/metabolismo , Adenoma Corticosuprarrenal/patología , Adenoma Corticosuprarrenal/sangre , ARN Mensajero/genética , ARN Mensajero/metabolismo , Carcinoma Corticosuprarrenal/genética , Carcinoma Corticosuprarrenal/metabolismo , Carcinoma Corticosuprarrenal/patología , Carcinoma Corticosuprarrenal/sangre , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/sangreRESUMEN
SLC30A9 (ZnT9) is a mitochondria-resident zinc transporter. Mutations in SLC30A9 have been reported in human patients with a novel cerebro-renal syndrome. Here, we show that ZnT9 is an evolutionarily highly conserved protein, with many regions extremely preserved among evolutionarily distant organisms. In Drosophila melanogaster (the fly), ZnT9 (ZnT49B) knockdown results in acutely impaired movement and drastic mitochondrial deformation. Severe Drosophila ZnT9 (dZnT9) reduction and ZnT9-null mutant flies are pupal lethal. The phenotype of dZnT9 knockdown can be partially rescued by mouse ZnT9 expression or zinc chelator TPEN, indicating the defect of dZnT9 loss is indeed a result of zinc dyshomeostasis. Interestingly, in the mouse, germline loss of Znt9 produces even more extreme phenotypes: the mutant embryos exhibit midgestational lethality with severe development abnormalities. Targeted mutagenesis of Znt9 in the mouse brain leads to serious dwarfism and physical incapacitation, followed by death shortly. Strikingly, the GH/IGF-1 signals are almost non-existent in these tissue-specific knockout mice, consistent with the medical finding in some human patients with severe mitochondrial deficiecny. ZnT9 mutations cause mitochondrial zinc dyshomeostasis, and we demonstrate mechanistically that mitochondrial zinc elevation quickly and potently inhibits the activities of respiration complexes. These results reveal the critical role of ZnT9 and mitochondrial zinc homeostasis in mammalian development. Based on our functional analyses, we finally discussed the possible nature of the so far identified human SLC30A9 mutations.
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Proteínas de Transporte de Catión , Desarrollo Embrionario , Mitocondrias , Zinc , Animales , Proteínas de Transporte de Catión/metabolismo , Proteínas de Transporte de Catión/genética , Humanos , Zinc/metabolismo , Ratones , Mitocondrias/metabolismo , Desarrollo Embrionario/genética , Drosophila melanogaster/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/embriología , Evolución Molecular , Ratones Noqueados , Secuencia de Aminoácidos , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Factores de Transcripción , Proteínas de Ciclo CelularRESUMEN
The escape of mitochondrial double-stranded dsRNA (mt-dsRNA) into the cytosol has been recently linked to a number of inflammatory diseases. Here, we report that the release of mt-dsRNA into the cytosol is a general feature of senescent cells and a critical driver of their inflammatory secretome, known as senescence-associated secretory phenotype (SASP). Inhibition of the mitochondrial RNA polymerase, the dsRNA sensors RIGI and MDA5, or the master inflammatory signaling protein MAVS, all result in reduced expression of the SASP, while broadly preserving other hallmarks of senescence. Moreover, senescent cells are hypersensitized to mt-dsRNA-driven inflammation due to their reduced levels of PNPT1 and ADAR1, two proteins critical for mitigating the accumulation of mt-dsRNA and the inflammatory potency of dsRNA, respectively. We find that mitofusin MFN1, but not MFN2, is important for the activation of the mt-dsRNA/MAVS/SASP axis and, accordingly, genetic or pharmacologic MFN1 inhibition attenuates the SASP. Finally, we report that senescent cells within fibrotic and aged tissues present dsRNA foci, and inhibition of mitochondrial RNA polymerase reduces systemic inflammation associated to senescence. In conclusion, we uncover the mt-dsRNA/MAVS/MFN1 axis as a key driver of the SASP and we identify novel therapeutic strategies for senescence-associated diseases.
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Senescencia Celular , Citosol , Inflamación , Mitocondrias , ARN Bicatenario , ARN Bicatenario/metabolismo , Humanos , Citosol/metabolismo , Mitocondrias/metabolismo , Inflamación/metabolismo , Inflamación/patología , Inflamación/genética , Animales , Proteína 58 DEAD Box/metabolismo , Proteína 58 DEAD Box/genética , Fenotipo Secretor Asociado a la Senescencia , Helicasa Inducida por Interferón IFIH1/metabolismo , Helicasa Inducida por Interferón IFIH1/genética , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Ratones , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , ARN Mitocondrial/metabolismo , ARN Mitocondrial/genética , Exorribonucleasas/metabolismo , Exorribonucleasas/genética , Receptores Inmunológicos/metabolismo , Receptores Inmunológicos/genética , Transducción de SeñalRESUMEN
Protein import and genome replication are essential processes for mitochondrial biogenesis and propagation. The J-domain proteins Pam16 and Pam18 regulate the presequence translocase of the mitochondrial inner membrane. In the protozoan Trypanosoma brucei, their counterparts are TbPam16 and TbPam18, which are essential for the procyclic form (PCF) of the parasite, though not involved in mitochondrial protein import. Here, we show that during evolution, the 2 proteins have been repurposed to regulate the replication of maxicircles within the intricate kDNA network, the most complex mitochondrial genome known. TbPam18 and TbPam16 have inactive J-domains suggesting a function independent of heat shock proteins. However, their single transmembrane domain is essential for function. Pulldown of TbPam16 identifies a putative client protein, termed MaRF11, the depletion of which causes the selective loss of maxicircles, akin to the effects observed for TbPam18 and TbPam16. Moreover, depletion of the mitochondrial proteasome results in increased levels of MaRF11. Thus, we have discovered a protein complex comprising TbPam18, TbPam16, and MaRF11, that controls maxicircle replication. We propose a working model in which the matrix protein MaRF11 functions downstream of the 2 integral inner membrane proteins TbPam18 and TbPam16. Moreover, we suggest that the levels of MaRF11 are controlled by the mitochondrial proteasome.
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Replicación del ADN , ADN Mitocondrial , Proteínas Protozoarias , Trypanosoma brucei brucei , Trypanosoma brucei brucei/metabolismo , Trypanosoma brucei brucei/genética , Proteínas Protozoarias/metabolismo , Proteínas Protozoarias/genética , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Mitocondrias/metabolismo , Mitocondrias/genética , Evolución MolecularRESUMEN
OBJECTIVES: To investigate the effect of Chinese medicine He's Yangchao recipe on premature ovarian insufficiency (POI) and its relationship with mitochondrial function of ovarian granulose cells in an animal model. METHODS: Thirty-six female C57BL/6J mice were randomly divided into blank control group, model group, low-, medium- and high-dose He's Yangchao recipe treatment group and coenzyme Q10 (Q10) treatment group (positive control). The POI model was induced by a single intraperitoneal injection of cyclophosphamide (90 mg/kg). The animals were sacrificed after 21 days. Primary granulose cells were obtained from POI mice and treated with He's Yangchao recipe, ERß inhibitor PHTPP, and He's Yangchao recipe+PHTPP in vitro for 24 h, respectively. Ovarian histopathological changes were observed by hematoxylin-eosin (HE) staining, ATP levels were detected by luciferase assay, mtDNA copy numbers were detected by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR), mitochondrial structure changes were observed by transmission electron microscopy, protein and mRNA expression levels of estrogen receptor ß (ERß), peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α), mitochondrial transcription factor A (TFAM), and superoxide dismutase 2 (SOD2) were detected by Western blotting and qRT-PCR. RESULTS: The ovarian tissue in model group exhibited few secondary and tertiary follicles, whereas the He's Yangchao recipe groups and Q10 group had abundant secondary and tertiary follicles. Compared with the blank control group, ATP and mtDNA levels in model group decreased (P<0.01), mitochondrial crista disappeared or abnormal vacuolated structure increased; the protein and mRNA levels of ERß, PGC1α, TFAM, and SOD2 decreased (all P<0.01). ATP production increased in granulose cells of high-dose He's Yangchao recipe group and Q10 group; mtDNA copy numbers increased (P<0.05 or P<0.01); abnormal mitochondrial structure was reduced; the protein and mRNA expressions of ERß, PGC1α, TFAM, and SOD2 increased (P<0.05 or P<0.01). Compared with the PHTPP intervention group, the proportion of normal mitochondrial structure in the granulose cells of He's Yangchao recipe + PHTPP group was higher; ATP content increased (P<0.05 or P<0.01); mtDNA copy numbers increased (P<0.05 or P<0.01); the protein and mRNA expression of ERß, PGC1α, TFAM and SOD2 increased (P<0.05 or P<0.01). CONCLUSIONS: He's Yangchao recipe can regulate mitochondrial biogenesis through ERß/PGC1α/TFAM pathway to improve ovarian function in POI mice.
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Proteínas de Unión al ADN , Receptor beta de Estrógeno , Ratones Endogámicos C57BL , Mitocondrias , Biogénesis de Organelos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Insuficiencia Ovárica Primaria , Factores de Transcripción , Femenino , Animales , Receptor beta de Estrógeno/metabolismo , Receptor beta de Estrógeno/genética , Ratones , Insuficiencia Ovárica Primaria/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Mitocondrias/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Medicamentos Herbarios Chinos/farmacología , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Superóxido Dismutasa/metabolismo , Proteínas del Grupo de Alta MovilidadRESUMEN
Endoplasmic reticulum (ER) stress induces the repression of protein synthesis throughout the cell. Attempts to understand how localized stress leads to widespread repression have been limited by difficulties in resolving translation rates at the subcellular level. Here, using live-cell imaging of reporter mRNA translation, we unexpectedly found that during ER stress, active translation at mitochondria was significantly protected. The mitochondrial protein ATPase family AAA domain-containing protein 3A (ATAD3A) interacted with protein kinase RNA-like endoplasmic reticulum kinase (PERK) and mediated this effect on localized translation by competing for binding with PERK's target, eukaryotic initiation factor 2 (eIF2). PERK-ATAD3A interactions increased during ER stress, forming mitochondria-ER contact sites. Furthermore, ATAD3A binding attenuated local PERK signaling and rescued the expression of some mitochondrial proteins. Thus, PERK-ATAD3A interactions can control translational repression at a subcellular level, mitigating the impact of ER stress on the cell.