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Vasodilation in response to low oxygen (O2) tension (hypoxic vasodilation) is an essential homeostatic response of systemic arteries that facilitates O2 supply to tissues according to demand. However, how blood vessels react to O2 deficiency is not well understood. A common belief is that arterial myocytes are O2-sensitive. Supporting this concept, it has been shown that the activity of myocyte L-type Ca2+channels, the main ion channels responsible for vascular contractility, is reversibly inhibited by hypoxia, although the underlying molecular mechanisms have remained elusive. Here, we show that genetic or pharmacological disruption of mitochondrial electron transport selectively abolishes O2 modulation of Ca2+ channels and hypoxic vasodilation. Mitochondria function as O2 sensors and effectors that signal myocyte Ca2+ channels due to constitutive Hif1α-mediated expression of specific electron transport subunit isoforms. These findings reveal the acute O2-sensing mechanisms of vascular cells and may guide new developments in vascular pharmacology.
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Subunidad alfa del Factor 1 Inducible por Hipoxia , Mitocondrias , Oxígeno , Vasodilatación , Animales , Mitocondrias/metabolismo , Oxígeno/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Ratones , Transducción de Señal , Masculino , Hipoxia/metabolismo , Ratones Endogámicos C57BL , Arterias/metabolismo , Canales de Calcio Tipo L/metabolismo , Canales de Calcio Tipo L/genética , Ratones Noqueados , Transporte de Electrón , Canales de Calcio/metabolismo , Canales de Calcio/genéticaRESUMEN
The TP53 tumor suppressor is frequently altered in lethal, castration-resistant prostate cancer (CRPC). However, to date there are no effective treatments that specifically target TP53 alterations. Using transcriptomic and metabolomic analyses, we showed here that TP53-altered prostate cancer (PCa) exhibits an increased dependency on asparagine and overexpresses asparagine synthetase (ASNS), the enzyme catalyzing the synthesis of asparagine. Mechanistically, loss or mutation of TP53 transcriptionally activated ASNS expression, directly as well as via mTORC1-mediated ATF4 induction, driving de novo asparagine biosynthesis to support CRPC growth. TP53-altered CRPC cells were sensitive to asparagine restriction by knockdown of ASNS or L-asparaginase treatment to deplete the intracellular and extracellular sources of asparagine, respectively, and cell viability was rescued by asparagine addition. Notably, pharmacological inhibition of intracellular asparagine biosynthesis using a glutaminase inhibitor and depletion of extracellular asparagine with L-asparaginase significantly reduced asparagine production and effectively impaired CRPC growth. This study highlights the significance of ASNS-mediated metabolic adaptation as a synthetic vulnerability in CRPC with TP53 alterations, providing a rationale for targeting asparagine production to treat these lethal prostate cancers.
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Microglia are necessary for central nervous system (CNS) function during development and play roles in ageing, Alzheimer's disease and the response to demyelinating injury1-5. The mitochondrial respiratory chain (RC) is necessary for conventional T cell proliferation6 and macrophage-dependent immune responses7-10. However, whether mitochondrial RC is essential for microglia proliferation or function is not known. We conditionally deleted the mitochondrial complex III subunit Uqcrfs1 (Rieske iron-sulfur polypeptide 1) in the microglia of adult mice to assess the requirement of microglial RC for survival, proliferation and adult CNS function in vivo. Notably, mitochondrial RC function was not required for survival or proliferation of microglia in vivo. RNA sequencing analysis showed that loss of RC function in microglia caused changes in gene expression distinct from aged or disease-associated microglia. Microglia-specific loss of mitochondrial RC function is not sufficient to induce cognitive decline. Amyloid-ß plaque coverage decreased and microglial interaction with amyloid-ß plaques increased in the hippocampus of 5xFAD mice with mitochondrial RC-deficient microglia. Microglia-specific loss of mitochondrial RC function did impair remyelination following an acute, reversible demyelinating event. Thus, mitochondrial respiration in microglia is dispensable for proliferation but is essential to maintain a proper response to CNS demyelinating injury.
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The circadian clock orchestrates vital physiological processes such as metabolism, immune function, and tissue regeneration, aligning them with the optimal time of day. This study identifies an intricate interplay between the circadian clock within muscle stem cells (SCs) and their capacity to modulate the immune microenvironment during muscle regeneration. We uncover that the SC clock provokes time of day-dependent induction of inflammatory response genes following injury, particularly those related to neutrophil activity and chemotaxis. These responses are driven by rhythms of cytosolic regeneration of the signaling metabolite NAD+. We demonstrate that genetically enhancing cytosolic NAD+ regeneration in SCs is sufficient to induce robust inflammatory responses that significantly influence muscle regeneration. Furthermore, using mononuclear single-cell sequencing of the regenerating muscle niche, we uncover a key role for the cytokine CCL2 in mediating SC-neutrophil crosstalk in a time of day-dependent manner. Our findings highlight a crucial intersection between SC metabolic shifts and immune responses within the muscle microenvironment, dictated by the circadian rhythms, and underscore the potential for targeting circadian and metabolic pathways to enhance tissue regeneration.
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Newborn mammalian cardiomyocytes quickly transition from a fetal to an adult phenotype that utilizes mitochondrial oxidative phosphorylation but loses mitotic capacity. We tested whether forced reversal of adult cardiomyocytes back to a fetal glycolytic phenotype would restore proliferative capacity. We deleted Uqcrfs1 (mitochondrial Rieske iron-sulfur protein, RISP) in hearts of adult mice. As RISP protein decreased, heart mitochondrial function declined, and glucose utilization increased. Simultaneously, the hearts underwent hyperplastic remodeling during which cardiomyocyte number doubled without cellular hypertrophy. Cellular energy supply was preserved, AMPK activation was absent, and mTOR activation was evident. In ischemic hearts with RISP deletion, new cardiomyocytes migrated into the infarcted region, suggesting the potential for therapeutic cardiac regeneration. RNA sequencing revealed upregulation of genes associated with cardiac development and proliferation. Metabolomic analysis revealed a decrease in α-ketoglutarate (required for TET-mediated demethylation) and an increase in S-adenosylmethionine (required for methyltransferase activity). Analysis revealed an increase in methylated CpGs near gene transcriptional start sites. Genes that were both differentially expressed and differentially methylated were linked to upregulated cardiac developmental pathways. We conclude that decreased mitochondrial function and increased glucose utilization can restore mitotic capacity in adult cardiomyocytes, resulting in the generation of new heart cells, potentially through the modification of substrates that regulate epigenetic modification of genes required for proliferation.
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Proliferación Celular , Mitocondrias Cardíacas , Miocitos Cardíacos , Animales , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Ratones , Mitocondrias Cardíacas/metabolismo , Mitocondrias Cardíacas/genética , Mitocondrias Cardíacas/patología , Ratones Noqueados , Complejo III de Transporte de Electrones/metabolismo , Complejo III de Transporte de Electrones/genética , Glucosa/metabolismoRESUMEN
The release of paused RNA polymerase II (RNAPII) from promoter-proximal regions is tightly controlled to ensure proper regulation of gene expression. The elongation factor PTEF-b is known to release paused RNAPII via phosphorylation of the RNAPII C-terminal domain by its cyclin-dependent kinase component, CDK9. However, the signal and stress-specific roles of the various RNAPII-associated macromolecular complexes containing PTEF-b/CDK9 are not yet clear. Here, we identify and characterize the CDK9 complex required for transcriptional response to hypoxia. Contrary to previous reports, our data indicate that a CDK9 complex containing BRD4 but not AFF1/4 is essential for this hypoxic stress response. We demonstrate that BRD4 bromodomains (BET) are dispensable for the release of paused RNAPII at hypoxia-activated genes and that BET inhibition by JQ1 is insufficient to impair hypoxic gene response. Mechanistically, we demonstrate that the C-terminal region of BRD4 is required for Polymerase-Associated Factor-1 Complex (PAF1C) recruitment to establish an elongation-competent RNAPII complex at hypoxia-responsive genes. PAF1C disruption using a small-molecule inhibitor (iPAF1C) impairs hypoxia-induced, BRD4-mediated RNAPII release. Together, our results provide insight into potentially targetable mechanisms that control the hypoxia-responsive transcriptional elongation.
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Proteínas Nucleares , Factores de Transcripción , Humanos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Regulación de la Expresión Génica , Quinasas Ciclina-Dependientes/metabolismo , Quinasa 9 Dependiente de la Ciclina/genética , Quinasa 9 Dependiente de la Ciclina/metabolismo , ARN Polimerasa II/genética , ARN Polimerasa II/metabolismo , Fosforilación , Hipoxia , Transcripción Genética , Factor B de Elongación Transcripcional Positiva/genética , Factor B de Elongación Transcripcional Positiva/metabolismo , Proteínas que Contienen Bromodominio , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismoRESUMEN
ABSTRACT: Chromosomal translocation (4;14), an adverse prognostic factor in multiple myeloma (MM), drives overexpression of the histone methyltransferase nuclear receptor binding SET domain protein 2 (NSD2). A genome-wide CRISPR screen in MM cells identified adenylate kinase 2 (AK2), an enzyme critical for high-energy phosphate transfer from the mitochondria, as an NSD2-driven vulnerability. AK2 suppression in t(4;14) MM cells decreased nicotinamide adenine dinucleotide phosphate (NADP[H]) critical for conversion of ribonucleotides to deoxyribonucleosides, leading to replication stress, DNA damage, and apoptosis. Driving a large genome-wide increase in chromatin methylation, NSD2 overexpression depletes S-adenosylmethionine, compromising the synthesis of creatine from its precursor, guanidinoacetate. Creatine supplementation restored NADP(H) levels, reduced DNA damage, and rescued AK2-deficient t(4;14) MM cells. As the creatine phosphate shuttle constitutes an alternative means for mitochondrial high-energy phosphate transport, these results indicate that NSD2-driven creatine depletion underlies the hypersensitivity of t(4;14) MM cells to AK2 loss. Furthermore, AK2 depletion in t(4;14) cells impaired protein folding in the endoplasmic reticulum, consistent with impaired use of mitochondrial adenosine triphosphate (ATP). Accordingly, AK2 suppression increased the sensitivity of MM cells to proteasome inhibition. These findings delineate a novel mechanism in which aberrant transfer of carbon to the epigenome creates a metabolic vulnerability, with direct therapeutic implications for t(4;14) MM.
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Adenilato Quinasa , N-Metiltransferasa de Histona-Lisina , Mieloma Múltiple , Translocación Genética , Humanos , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Adenilato Quinasa/metabolismo , Adenilato Quinasa/genética , Cromosomas Humanos Par 14/genética , Epigenoma , Cromosomas Humanos Par 4/genética , Carbono/metabolismo , Línea Celular Tumoral , Proteínas RepresorasRESUMEN
Cellular purines, particularly adenosine 5'-triphosphate (ATP), fuel many metabolic reactions, but less is known about the direct effects of pyrimidines on cellular metabolism. We found that pyrimidines, but not purines, maintain pyruvate oxidation and the tricarboxylic citric acid (TCA) cycle by regulating pyruvate dehydrogenase (PDH) activity. PDH activity requires sufficient substrates and cofactors, including thiamine pyrophosphate (TPP). Depletion of cellular pyrimidines decreased TPP synthesis, a reaction carried out by TPP kinase 1 (TPK1), which reportedly uses ATP to phosphorylate thiamine (vitamin B1). We found that uridine 5'-triphosphate (UTP) acts as the preferred substrate for TPK1, enabling cellular TPP synthesis, PDH activity, TCA-cycle activity, lipogenesis, and adipocyte differentiation. Thus, UTP is required for vitamin B1 utilization to maintain pyruvate oxidation and lipogenesis.
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Ciclo del Ácido Cítrico , Lipogénesis , Pirimidinas , Complejo Piruvato Deshidrogenasa , Piruvatos , Adenosina Trifosfato/metabolismo , Pirimidinas/metabolismo , Piruvatos/metabolismo , Tiamina/metabolismo , Tiamina Pirofosfato/metabolismo , Uridina Trifosfato/metabolismo , Oxidación-Reducción , Proteínas Quinasas/metabolismo , Humanos , Células HeLa , Complejo Piruvato Deshidrogenasa/metabolismoRESUMEN
Mature oligodendrocytes (OLG) are the myelin-forming cells of the central nervous system. Recent work has shown a dynamic role for these cells in the plasticity of neural circuits, leading to a renewed interest in voltage-sensitive currents in OLG. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and their respective current (Ih) were recently identified in mature OLG and shown to play a role in regulating myelin length. Here we provide a biochemical and electrophysiological characterization of HCN channels in cells of the oligodendrocyte lineage. We observed that mice with a nonsense mutation in the Hcn2 gene (Hcn2ap/ap) have less white matter than their wild type counterparts with fewer OLG and fewer oligodendrocyte progenitor cells (OPCs). Hcn2ap/ap mice have severe motor impairments, although these deficits were not observed in mice with HCN2 conditionally eliminated only in oligodendrocytes (Cnpcre/+; Hcn2F/F). However, Cnpcre/+; Hcn2F/F mice develop motor impairments more rapidly in response to experimental autoimmune encephalomyelitis (EAE). We conclude that HCN2 channels in OLG may play a role in regulating metabolism.
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Antitumor responses of CD8+ T cells are tightly regulated by distinct metabolic fitness. High levels of glutathione (GSH) are observed in the majority of tumors, contributing to cancer progression and treatment resistance in part by preventing glutathione peroxidase 4-dependent (GPX4-dependent) ferroptosis. Here, we show the necessity of adenosine A2A receptor (A2AR) signaling and the GSH/GPX4 axis in orchestrating metabolic fitness and survival of functionally competent CD8+ T cells. Activated CD8+ T cells treated ex vivo with simultaneous inhibition of A2AR and lipid peroxidation acquire a superior capacity to proliferate and persist in vivo, demonstrating a translatable means to prevent ferroptosis in adoptive cell therapy. Additionally, we identify a particular cluster of intratumoral CD8+ T cells expressing a putative gene signature of GSH metabolism (GMGS) in association with clinical response and survival across several human cancers. Our study addresses a key role of GSH/GPX4 and adenosinergic pathways in fine-tuning the metabolic fitness of antitumor CD8+ T cells.
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Neoplasias , Receptor de Adenosina A2A , Humanos , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Receptor de Adenosina A2A/genética , Receptor de Adenosina A2A/metabolismo , Neoplasias/genética , Neoplasias/terapia , Neoplasias/metabolismo , Linfocitos T CD8-positivos/metabolismo , Glutatión/metabolismoRESUMEN
Mutations in genes that affect mitochondrial function cause primary mitochondrial diseases. Mitochondrial diseases are highly heterogeneous and even patients with the same mitochondrial disease can exhibit broad phenotypic heterogeneity, which is poorly understood. Mutations in subunits of mitochondrial respiratory complex I cause complex I deficiency, which can result in severe neurological symptoms and death in infancy. However, some complex I deficiency patients present with much milder symptoms. The most common nuclear gene mutated in complex I deficiency is the highly conserved core subunit NDUFS1. To model the phenotypic heterogeneity in complex I deficiency, we used RNAi lines targeting the Drosophila NDUFS1 homolog ND-75 with different efficiencies. Strong knockdown of ND-75 in Drosophila neurons resulted in severe behavioural phenotypes, reduced lifespan, altered mitochondrial morphology, reduced endoplasmic reticulum (ER)-mitochondria contacts and activation of the unfolded protein response (UPR). By contrast, weak ND-75 knockdown caused much milder behavioural phenotypes and changes in mitochondrial morphology. Moreover, weak ND-75 did not alter ER-mitochondria contacts or activate the UPR. Weak and strong ND-75 knockdown resulted in overlapping but distinct transcriptional responses in the brain, with weak knockdown specifically affecting proteosome activity and immune response genes. Metabolism was also differentially affected by weak and strong ND-75 knockdown including gamma-aminobutyric acid (GABA) levels, which may contribute to neuronal dysfunction in ND-75 knockdown flies. Several metabolic processes were only affected by strong ND-75 knockdown including the pentose phosphate pathway and the metabolite 2-hydroxyglutarate (2-HG), suggesting 2-HG as a candidate biomarker of severe neurological mitochondrial disease. Thus, our Drosophila model provides the means to dissect the mechanisms underlying phenotypic heterogeneity in mitochondrial disease.
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Drosophila , Complejo I de Transporte de Electrón/deficiencia , Enfermedades Mitocondriales , Animales , Humanos , Drosophila/genética , Drosophila/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Enfermedades Mitocondriales/genética , Enfermedades Mitocondriales/metabolismo , FenotipoRESUMEN
Glioblastoma (GBM) is a malignancy dominated by the infiltration of tumor-associated myeloid cells (TAMCs). Examination of TAMC metabolic phenotypes in mouse models and patients with GBM identified the de novo creatine metabolic pathway as a hallmark of TAMCs. Multi-omics analyses revealed that TAMCs surround the hypoxic peri-necrotic regions of GBM and express the creatine metabolic enzyme glycine amidinotransferase (GATM). Conversely, GBM cells located within these same regions are uniquely specific in expressing the creatine transporter (SLC6A8). We hypothesized that TAMCs provide creatine to tumors, promoting GBM progression. Isotopic tracing demonstrated that TAMC-secreted creatine is taken up by tumor cells. Creatine supplementation protected tumors from hypoxia-induced stress, which was abrogated with genetic ablation or pharmacologic inhibition of SLC6A8. Lastly, inhibition of creatine transport using the clinically relevant compound, RGX-202-01, blunted tumor growth and enhanced radiation therapy in vivo. This work highlights that myeloid-to-tumor transfer of creatine promotes tumor growth in the hypoxic niche.
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Glioblastoma , Ratones , Animales , Humanos , Glioblastoma/metabolismo , Creatina , Hipoxia/metabolismo , Células Mieloides/metabolismo , Células Progenitoras Mieloides , Línea Celular TumoralRESUMEN
Poxviruses are unusual DNA viruses that replicate in the cytoplasm. To do so, they encode approximately 100 immunomodulatory proteins that counteract cytosolic nucleic acid sensors such as cGAMP synthase (cGAS) along with several other antiviral response pathways. Yet most of these immunomodulators are expressed very early in infection while many are variable host range determinants, and significant gaps remain in our understanding of poxvirus sensing and evasion strategies. Here, we show that after infection is established, subsequent progression of the viral lifecycle is sensed through specific changes to mitochondria that coordinate distinct aspects of the antiviral response. Unlike other viruses that cause extensive mitochondrial damage, poxviruses sustain key mitochondrial functions including membrane potential and respiration while reducing reactive oxygen species that drive inflammation. However, poxvirus replication induces mitochondrial hyperfusion that independently controls the release of mitochondrial DNA (mtDNA) to prime nucleic acid sensors and enables an increase in glycolysis that is necessary to support interferon stimulated gene (ISG) production. To counter this, the poxvirus F17 protein localizes to mitochondria and dysregulates mTOR to simultaneously destabilize cGAS and block increases in glycolysis. Our findings reveal how the poxvirus F17 protein disarms specific mitochondrially orchestrated responses to later stages of poxvirus replication.
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Ácidos Nucleicos , Poxviridae , Poxviridae/genética , Poxviridae/metabolismo , Citoplasma , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Antivirales/farmacología , Antivirales/metabolismo , Ácidos Nucleicos/metabolismoRESUMEN
Ischemic acute kidney injury (AKI) is common in hospitalized patients and increases the risk for chronic kidney disease (CKD). Impaired endothelial cell (EC) functions are thought to contribute in AKI to CKD transition, but the underlying mechanisms remain unclear. Here, we identify a critical role for endothelial oxygen sensing prolyl hydroxylase domain (PHD) enzymes 1-3 in regulating post-ischemic kidney repair. In renal endothelium, we observed compartment-specific differences in the expression of the three PHD isoforms in both mice and humans. We found that post-ischemic concurrent inactivation of endothelial PHD1, PHD2, and PHD3 but not PHD2 alone promoted maladaptive kidney repair characterized by exacerbated tissue injury, fibrosis, and inflammation. Single-cell RNA-seq analysis of the post-ischemic endothelial PHD1, PHD2 and PHD3 deficient (PHDTiEC) kidney revealed an endothelial glycolytic transcriptional signature, also observed in human kidneys with severe AKI. This metabolic program was coupled to upregulation of the SLC16A3 gene encoding the lactate exporter monocarboxylate transporter 4 (MCT4). Strikingly, treatment with the MCT4 inhibitor syrosingopine restored adaptive kidney repair in PHDTiEC mice. Mechanistically, MCT4 inhibition suppressed pro-inflammatory EC activation reducing monocyte-endothelial cell interaction. Our findings suggest avenues for halting AKI to CKD transition based on selectively targeting the endothelial hypoxia-driven glycolysis/MCT4 axis.
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Apolipoprotein E (ApoE) is recognized for its pleiotropic properties that suppress inflammation. We report that ApoE serves as a metabolic rheostat that regulates microRNA control of glycolytic and mitochondrial activity in myeloid cells and hematopoietic stem and progenitor cells (HSPCs). ApoE expression in myeloid cells increases microRNA-146a, which reduces nuclear factor κB (NF-κB)-driven GLUT1 expression and glycolytic activity. In contrast, ApoE expression reduces microRNA-142a, which increases carnitine palmitoyltransferase 1a (CPT1A) expression, fatty acid oxidation, and oxidative phosphorylation. Improved mitochondrial metabolism by ApoE expression causes an enrichment of tricarboxylic acid (TCA) cycle metabolites and nicotinamide adenine dinucleotide (NAD+) in macrophages. The study of mice with conditional ApoE expression supports the capacity of ApoE to foster microRNA-controlled immunometabolism. Modulation of microRNA-146a and -142a in the hematopoietic system of hyperlipidemic mice using RNA mimics and antagonists, respectively, improves mitochondrial metabolism, which suppresses inflammation and hematopoiesis. Our findings unveil microRNA regulatory circuits, controlled by ApoE, that exert metabolic control over hematopoiesis and inflammation in hyperlipidemia.
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Hiperlipidemias , Enfermedades Metabólicas , MicroARNs , Ratones , Animales , Hiperlipidemias/genética , Hiperlipidemias/metabolismo , Inflamación/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Hematopoyesis , Apolipoproteínas E/genéticaRESUMEN
Over the past decade or two, targeting metabolism has been effective in the treatment of many diseases and disorders, particularly cancer. In a metabolism focus issue in Cell Chemical Biology, this Voices piece asks researchers from a range of backgrounds: what are some major challenges and opportunities facing the field in the coming years?
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Alveolar epithelial type 1 (AT1) cells are necessary to transfer oxygen and carbon dioxide between the blood and air. Alveolar epithelial type 2 (AT2) cells serve as a partially committed stem cell population, producing AT1 cells during postnatal alveolar development and repair after influenza A and SARS-CoV-2 pneumonia1-6. Little is known about the metabolic regulation of the fate of lung epithelial cells. Here we report that deleting the mitochondrial electron transport chain complex I subunit Ndufs2 in lung epithelial cells during mouse gestation led to death during postnatal alveolar development. Affected mice displayed hypertrophic cells with AT2 and AT1 cell features, known as transitional cells. Mammalian mitochondrial complex I, comprising 45 subunits, regenerates NAD+ and pumps protons. Conditional expression of yeast NADH dehydrogenase (NDI1) protein that regenerates NAD+ without proton pumping7,8 was sufficient to correct abnormal alveolar development and avert lethality. Single-cell RNA sequencing revealed enrichment of integrated stress response (ISR) genes in transitional cells. Administering an ISR inhibitor9,10 or NAD+ precursor reduced ISR gene signatures in epithelial cells and partially rescued lethality in the absence of mitochondrial complex I function. Notably, lung epithelial-specific loss of mitochondrial electron transport chain complex II subunit Sdhd, which maintains NAD+ regeneration, did not trigger high ISR activation or lethality. These findings highlight an unanticipated requirement for mitochondrial complex I-dependent NAD+ regeneration in directing cell fate during postnatal alveolar development by preventing pathological ISR induction.
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Células Epiteliales Alveolares , Diferenciación Celular , Linaje de la Célula , Pulmón , Mitocondrias , Estrés Fisiológico , Animales , Ratones , Células Epiteliales Alveolares/citología , Células Epiteliales Alveolares/metabolismo , Células Epiteliales Alveolares/patología , Pulmón/citología , Pulmón/metabolismo , Pulmón/patología , Mitocondrias/enzimología , Mitocondrias/metabolismo , NAD/metabolismo , NADH Deshidrogenasa/metabolismo , Protones , RNA-Seq , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Análisis de Expresión Génica de una Sola CélulaRESUMEN
Histone H4 lysine 16 acetylation (H4K16ac), governed by the histone acetyltransferase MOF, orchestrates gene expression regulation and chromatin interaction. However, the roles of MOF and H4K16ac in controlling cellular function and regulating mammalian tissue development remain unclear. Here we show that conditional deletion of Mof in the skin, but not Kansl1, causes severe defects in the self-renewal of basal epithelial progenitors, epidermal differentiation, and hair follicle growth, resulting in barrier defects and perinatal lethality. MOF-regulated genes are highly enriched for essential functions in the mitochondria and cilia. Genetic deletion of Uqcrq, an essential subunit for the electron transport chain (ETC) Complex III, in the skin, recapitulates the defects in epidermal differentiation and hair follicle growth observed in MOF knockout mouse. Together, this study reveals the requirement of MOF-mediated epigenetic mechanism for regulating mitochondrial and ciliary gene expression and underscores the important function of the MOF/ETC axis for mammalian skin development.
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Histonas , Lisina , Animales , Ratones , Histonas/metabolismo , Lisina/metabolismo , Acetilación , Cromatina/metabolismo , Mitocondrias/metabolismo , Histona Acetiltransferasas/metabolismo , Mamíferos/genéticaRESUMEN
Mammalian retinal metabolism favors aerobic glycolysis. However, the role of glycolytic metabolism in retinal morphogenesis remains unknown. We report that aerobic glycolysis is necessary for the early stages of retinal development. Taking advantage of an unbiased approach that combines the use of eye organoids and single-cell RNA sequencing, we identify specific glucose transporters and glycolytic genes in retinal progenitors. Next, we determine that the optic vesicle territory of mouse embryos displays elevated levels of glycolytic activity. At the functional level, we show that removal of Glucose transporter 1 and Lactate dehydrogenase A gene activity from developing retinal progenitors arrests eye morphogenesis. Surprisingly, we uncover that lactate-mediated upregulation of key eye-field transcription factors is controlled by the epigenetic modification of histone H3 acetylation through histone deacetylase activity. Our results identify an unexpected bioenergetic independent role of lactate as a signaling molecule necessary for mammalian eye morphogenesis.