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DeBerardinis, R. J.

Publications and source records attributed to DeBerardinis, R. J..

At least 19 recordsLinked to original sources

Choline Kinase Alpha Inhibition is a Mutation Agnostic Therapeutic Vulnerability in Clonal Hematopoiesis

Clonal Hematopoiesis (CH) affects the aging population and is associated with increased risk of hematological malignancy, cardiovascular disease, and all-cause mortality. Therapeutic options for CH remain limited. Using hematopoietic stem and progenitor cell (HSPC) color barcoding and mosaic mutagenesis in zebrafish, we identified perturbed choline metabolism and increased phosphatidylcholine (PC) biosynthesis via choline kinase alpha (CHKA) in asxl1-mutant HSPCs. Suppressing CHKA-dependent choline flux reduced ASXL1-driven clonal expansion. This effect was conserved in a murine DNMT3A and human TET2 model. Mechanistically, CHKA- dependent choline flux controls phosphatidylcholine production that supports platelet activating factor (PAF) production. Exogenous PAF overcomes the suppressive effect of CHKA inhibition in ASXL1 and TET2 models. We isolated primary, human HSPCs from the peripheral blood of patients with endogenous ASXL1 mutations and demonstrated that perturbing PAF signaling reduces their competitive potential in an ex vivo clonal competition assay. This CHKA/PAF axis is conserved in TET2-mutant HSPCs. Together, these findings identify a mutation agnostic metabolic dependency across the three most common CH genotypes and demonstrate that targeting the CHKA-dependent choline flux suppresses clonal expansion.

cancer biology↗

The liver compensates for zonal loss of glucose 6-phosphatase to prevent glycogen storage disease

The liver is organized into spatial zones with distinct metabolic roles, but how this architecture contributes to disease remains unclear. Glucose production is concentrated in periportal hepatocytes and depends on G6PC1; loss of this enzyme causes glycogen storage disease type Ia (GSD1a). We tested whether G6PC1 loss in specific zones, including its primary periportal location, is sufficient to cause disease. Unexpectedly, loss of G6pc1 in any single zone caused local glycogen accumulation but did not produce the systemic metabolic abnormalities or liver tumors seen after whole-liver deletion. Instead, disease developed only after near-complete loss of G6pc1 across the entire liver. These findings show that organ-wide compensation preserves metabolic homeostasis and suppresses tumorigenesis despite localized disruption. TeaserSpatial G6pc1 loss causes local glycogen storage without systemic metabolic disease.

physiology↗

MitoSAM-dependent lipoylation controls postnatal heart development via metabolic remodeling

The neonatal heart undergoes a rapid metabolic transition from fetal glycolysis to oxidative phosphorylation, requiring coordinated metabolic remodeling. Mechanisms driving this transition remain unclear. Here, we demonstrate that sufficient mitochondrial S-adenosylmethionine (mitoSAM), imported via the solute carrier Slc25a26, is essential for this shift by sustaining the lipoylation of 2-oxoacid dehydrogenases, critical for TCA cycle activation. Proteomic and metabolomic profiling revealed that reduced mitoSAM availability impaired lipoylation, blocking TCA cycle function and restricting nucleotide synthesis, while mitochondrial gene expression and respiratory capacity remained largely intact. In vivo EdU labeling showed persistent cardiomyocyte proliferation imposing further strain on nucleotide pools. Supplementation with medium-chain triglycerides during the suckling-to-weaning transition restored metabolic function and normalized cardiac growth and morphology. Our data reveal a critical developmental window in which mitoSAM-dependent lipoylation ensures heart maturation.

biochemistry↗

UFMylation of Pyruvate Dehydrogenase Regulates Mitochondrial Metabolism

The ubiquitin-fold modifier 1 (UFM1) post-translational modification (PTM), or UFMylation, regulates protein homeostasis and is essential for human development. Yet the roles of the de-UFMylase, UFM1-specific peptidase 2 (UFSP2), which removes UFM1 from UFMylated proteins, remain poorly characterized. Here, we demonstrate that UFMylation and UFSP2 regulate mitochondrial metabolism. Quantitative proteomics in UFSP2-deficient cells revealed the accumulation of many proteins previously unknown to be impacted by UFMylation. These included components of the mitochondrial ribosome, electron transport chain (ETC), and pyruvate dehydrogenase (PDH) complex. Functional analyses demonstrated that excessive UFMylation in UFSP2-deficient cells increases mitochondrial respiration, glucose oxidation in the tricarboxylic acid (TCA) cycle, and PDH enzymatic activity. We identified dihydrolipoamide S-acetyltransferase (DLAT), the E2 component of PDH, as a direct UFMylation substrate, with lysine 118 (K118) as the primary conjugation site. Mutating K118 to arginine (K118R) abolished DLAT UFMylation and reduced pyruvate oxidation, identifying this modification as an activator of PDH. These findings reveal a UFMylation-based regulatory mechanism that controls mitochondrial function by inducing utilization of pyruvate as a TCA cycle fuel.

biochemistry↗

Characterizing the metabolomes of microglia, astrocytes, and neurons in aging and Alzheimer's brains

Neurons and glia are distinct in their morphology, development, and function, possessing unique transcriptomes and proteomes, but little is known about their metabolomes. The challenge of brain cell metabolic profiling is to obtain a large number of cells for reliable analysis. Here, we purified microglia, astrocytes, and neurons from mouse brains, identifying >70 metabolites through targeted metabolomics and 9,854 metabolite features via untargeted metabolomics. We systematically characterized cell type-enriched metabolites and metabolic pathways, revealing an enrichment of glutathione (GSH) and polyamine metabolism in microglia. This enrichment was validated in vivo and showed significant decreases with aging and in an Alzheimers disease (AD) model. Notably, GSH and polyamine metabolism correlated strongly with chemokine-related gene expression. Disrupting the GSH pathway in microglia resulted in downregulation of chemokine-related genes, aberrant morphogenesis, and {beta}-amyloid deposition. Our results provide a valuable resource (https://metabolismocean.org/braincell) for metabolic studies related to aging, AD, and other neurological diseases.

neuroscience↗

Leptin Receptor+ cells create a perisinusoidal niche for thrombopoiesis in the bone marrow by synthesizing CXCL14

Leptin Receptor-expressing (LepR+) stromal cells in the bone marrow are a critical source of growth factors for the maintenance of hematopoietic stem cells (HSCs) and most restricted hematopoietic progenitors. An important unresolved question is whether they also regulate terminal differentiation in some hematopoietic cells. We found that LepR+ cells promote thrombopoiesis by synthesizing the chemokine CXCL14, which is expressed in the bone marrow by a subset of LepR+ cells. Cxcl14-expressing LepR+ cells extend fine processes that wrap around perisinusoidal megakaryocytes. Deletion of Cxcl14 from LepR+ cells did not significantly alter HSC function or most aspects of bone marrow hematopoiesis, including megakaryocyte generation; however, it significantly reduced the numbers of proplatelet-forming megakaryocytes in the bone marrow and platelets in the blood. CXCL14 promoted platelet formation by remodeling lipid metabolism in megakaryocytes, increasing fatty acid transporter expression and enabling megakaryocytes to take up more polyunsaturated fatty acids from circulation. A high fat diet rescued the formation of proplatelet-forming megakaryocytes and platelets in Lepr-cre; Cxcl14 fl/fl mice. CXCL14 protein was sufficient to promote platelet formation by megakaryocytes in vitro and in vivo. LepR+ cells thus create a perisinusoidal niche for thrombopoiesis by producing CXCL14, which regulates lipid metabolism and terminal differentiation in megakaryocytes. Key pointsO_LILeptin Receptor+ stromal cells regulate terminal differentiation in megakaryocytes in addition to maintaining stem and progenitor cells C_LIO_LICXCL14 from Leptin Receptor+ cells promotes the formation of platelets by remodeling lipid metabolism in megakaryocytes in the bone marrow C_LI

cell biology↗

Carbohydrate adaptation drives liver-brain axis maturation

Mammalian postnatal life requires adaptation to a carbohydrate-rich diet, yet how metabolic programs are coordinated within and across organs is unclear. Using time-resolved transcriptomic and metabolomic analyses from the neonatal period through adulthood, we show that mouse liver rapidly acquires oxidative and detoxification capacity after weaning. This transition enables the brain to establish energy-sufficient, low-toxicity metabolic environment for neuronal development. This maturation process is marked by progressive activation of the hepatic electron transport chain (ETC), with the mitochondrial RNA endoribonuclease LACTB2 acting as a key regulator. LACTB2 prevents the accumulation of mitochondrial RNAs and sustains expression of mtDNA-encoded ETC subunits, thereby preserving mitochondrial competence for oxidative metabolism. LACTB2 is postnatally induced in hepatocytes, and its loss causes defective glucose utilization, systemic metabolic toxicity, and impaired brain metabolism and myelination, leading to prepubertal lethality, particularly in males. Restoring ETC function through liver-targeted expression of yeast NADH dehydrogenase NDI1, inhibiting the integrated stress response or ammonia scavenging improved survival. Our findings identify LACTB2-dependent hepatic mitochondrial maturation as a central mechanism that aligns carbohydrate adaptation with the liver-brain metabolic coordination to support early-life development.

developmental biology↗

Autophagy disruption primes CAR-T cell metabolism for sustained rejection of ovarian tumors

T-cell based immunotherapies such as chimeric antigen receptor T (CAR-T) cell therapy face substantial hurdles when confronting solid tumors such as ovarian cancer, where metabolic constraints in the tumor microenvironment limit T cell infiltration and function. In particular, T cells exposed to nutrient deprivation and hypoxia upregulate autophagy, a lysosomal degradation pathway that negatively regulates effector responses. Here, we used CRISPR-Cas9 to target a folate receptor alpha (FR) CAR expression cassette into the locus of the essential autophagy gene ATG5, thereby generating autophagy-deficient CAR-T cells in a single editing step. Targeted metabolite profiling revealed that deletion of ATG5 induced widespread metabolic reprogramming characterized by increased glucose and amino acid uptake. Functionally, ATG5-knockout CAR-T cells maintained high cytolytic activity when assayed in patient-derived ascites in vitro, and exhibited superior and long-lasting tumor control against ovarian tumors in vivo. Taken together, our results suggest that deletion of ATG5 metabolically primes CAR-T cells for enhanced cytotoxicity in immune-suppressive conditions, thereby improving the therapeutic potential of FR CAR-T cells for ovarian cancer immunotherapy.

immunology↗

Methionine regulates antitumor function of CD8⁺ T cells through polyamine synthesis

Methionine is an essential amino acid critical for T cell activation. While methionine restriction (MR) combined with immune checkpoint blockade has been shown to enhance T cell function, the impact of methionine on adoptive T cell therapies is largely unexplored. Here, we examined the functionality of T cells under MR and pharmaceutical inhibition of the methionine cycle (MAT2Ai), using primary T cells and a murine adoptive T cell therapy model. In vitro, transient MR or MAT2Ai treatment increased interferon gamma (IFN{gamma}) expression in CD8+ T cells, whereas sustained MR led to the upregulation of T cell exhaustion-associated markers. Mechanistically, transient MR suppressed the polyamine synthesis pathway, and supplementation with polyamines reversed MR-induced IFN{gamma} expression. Genetic ablation of s-adenosylmethionine decarboxylase, an enzyme in the polyamine synthesis pathway, recapitulated the effect of MR, indicating that transient MR enhances T cell function by inhibiting polyamine synthesis. Despite this, transient MR treatment of ovalbumin (OVA)-specific (OT-I) CD8+ T cells prior to adoptive transfer did not improve antitumor efficacy against EG7-OVA tumors in vivo. In contrast, sustained dietary MR accelerated EG7-OVA tumor growth in mice treated with OT-I T cells, demonstrating that methionine availability is essential for the activity of adoptively transferred T cells. These findings suggest that enhancing methionine availability in the tumor microenvironment may improve the efficacy of adoptive T cell therapies.

immunology↗

Mutant IDH silences GSX2 to reprogram neural progenitor cell fate and promote gliomagenesis

Isocitrate dehydrogenase (IDH) mutations arise early in gliomas and are associated with a defined neurodevelopmental cancer cell hierarchy. However, how mutant IDH contributes to this hierarchy and whether this interaction promotes gliomagenesis remain unclear. We captured the dynamics of IDH-mutant glioma initiation in genetically engineered mice through time-resolved, single-cell genomics. Mutant IDH activates and induces lineage switching of neural progenitor cells (NPCs). These actions expand oligodendrocyte precursor cells, the predominant cell-of-origin for these tumors, at the expense of interneurons. Lineage switching is mediated by promoter hypermethylation and silencing of Gsx2, a homeobox gene required for neurogenesis. Critically, Gsx2 ablation recapitulates NPC fate reprogramming by mutant IDH. We provide a new model of neural cell fate control by IDH oncogenes and insights into the developmental origins of glioma.

cancer biology↗

Nitrogen metabolism profiling reveals cell state-specific pyrimidine synthesis pathway choice

Conventional stable isotope tracing assays track one or several metabolites. However, cells use an array of nutrients to sustain nitrogen metabolic pathways. This incongruency hampers a system level understanding of cellular nitrogen metabolism. Therefore, we created a platform to simultaneously trace 30 nitrogen isotope-labeled metabolites. This platform revealed that while primitive cells engage both de novo and salvage pyrimidine synthesis pathways, differentiated cells nearly exclusively salvage uridine despite expressing de novo pathway enzymes. This link between cell state and pyrimidine synthesis routes persisted in physiological contexts, including primary murine and human tissues and tumor xenografts. Mechanistically, we found that Ser1900 phosphorylation of CAD, the first enzyme of the de novo pathway, was enriched in primitive cells and that mimicking this modification in differentiated cells abrogated their preference for pyrimidine salvage. Collectively, we establish a method for nitrogen metabolism profiling and define a mechanism of cell state-specific pyrimidine synthesis pathway choice.

cell biology↗

L-2-hydroxyglutarate impairs neuronal differentiation through epigenetic activation of MYC expression

High levels of L- and D-2-hydroxyglutarate, the reduced forms of -ketoglutarate (KG), are implicated in human neurodevelopmental disorders and cancer. Both enantiomers exert effects on epigenetics by modulating a family of KG-dependent dioxygenases involved in histone, DNA and RNA demethylation. L-2HG dehydrogenase (L2HGDH) converts L-2HG to KG. Its deficiency is a rare, autosomal recessive inborn error of metabolism (IEM) characterized by systemic elevations of L-2HG, progressive neurological disability and a high risk of malignancy in the brain. The mechanisms behind these aberrations are unknown. Here we used an isogenic, patient-derived induced pluripotent stem cell (iPSC) system to study the impact of L2HGDH deficiency on neural progenitor cell (NPC) function and neuronal differentiation. We demonstrate that L2HGDH deficiency causes accumulation of L-2HG, NPC hyperproliferation, increased clonogenicity, excessive growth, and defective neuronal differentiation in 2D cultures and cortical spheroids. Editing the L2HGDH locus to wild-type reverses these effects. Blocking L-2HG accumulation in NPCs with a glutaminase inhibitor also induces neuronal differentiation. L-2HG-dependent inhibition of KDM5 histone demethylases leads to widespread retention of H3K4me2 and H3K4me3, markers of active gene expression. These marks are prominently elevated at the MYC locus in L2HGDH-deficient cells, and consequently cells express high MYC both in 2D culture and in many distinct cell types within cortical spheroids. Although thousands of loci display altered histone methylation, genetically or pharmacologically normalizing MYC is sufficient to completely reverse defective neuronal differentiation. These data indicate that the primary metabolic disturbance in an iPSC IEM model activates the MYC oncogene, favoring stem cell self-renewal and suppressing lineage commitment to neurons.

genetics↗

A transcriptional biosensor reveals mechanisms of α-ketoglutarate signaling to chromatin

Alpha-ketoglutarate (KG) is required for chromatin demethylation but mechanisms controlling KG abundance in the nucleus are poorly defined. Therefore, we designed a biosensor system to monitor this metabolite pool in human cells using an KG-responsive cyanobacterial transcription factor, NtcA. We then coupled this system with a genetic screen to identify genes that regulate KG in the nucleus, defining an inter-organelle pathway in which sequential mitochondrial activities of the GPT2 transaminase and SLC25A11 transporter supply nuclear KG. Using a mouse model of GPT2 deficiency, a human inborn error of metabolism, we found that this pathway controls chromatin methylation in the developing brain. Our work provides a tool to assess KG signaling to chromatin and a framework for leveraging forward genetics to study nuclear metabolite pools.

synthetic biology↗

Transmembrane Serine Protease TMPRSS11B promotes an acidified tumor microenvironment and immune suppression in lung squamous cell carcinoma

Lung cancer is the leading cause of cancer-related deaths worldwide. Existing therapeutic options have limited efficacy, particularly for lung squamous cell carcinoma (LUSC), underscoring the critical need for the identification of new therapeutic targets. We previously demonstrated that the Transmembrane Serine Protease TMPRSS11B promotes transformation of human bronchial epithelial cells and enhances lactate export from LUSC cells. To determine the impact of TMPRSS11B activity on the host immune system and the tumor microenvironment (TME), we evaluated the effect of Tmprss11b depletion in a syngeneic mouse model. Tmprss11b depletion significantly reduced tumor burden in immunocompetent mice and triggered an infiltration of immune cells. RNA FISH analysis and spatial transcriptomics in the autochthonous Rosa26-Sox2-Ires-GfpLSL/LSL; Nkx2-1fl/fl; Lkb1fl/fl (SNL) model revealed an enrichment of Tmprss11b expression in LUSC tumors, specifically in Krt13+ hillock-like cells. Ultra-pH sensitive nanoparticle imaging and metabolite analysis identified regions of acidification, elevated lactate, and enrichment of M2-like macrophages in LUSC tumors. These results demonstrate that TMPRSS11B promotes an acidified and immunosuppressive TME and nominate this enzyme as a therapeutic target in LUSC.

cancer biology↗

NUDT5 regulates purine metabolism and thiopurine sensitivity by interacting with PPAT

Cells generate purine nucleotides through both de novo purine biosynthesis (DNPB) and purine salvage. Purine accumulation represses energetically costly DNPB through feedback inhibition of the enzymatic steps that produce the precursor phosphoribosylamine. Excessive DNPB is associated with human diseases including neurological dysfunction and hyperuricemia. However, the mechanisms explaining how cells balance DNPB and purine salvage are incompletely understood. Data from a genome-wide CRISPR loss-of-function screen and extensive stable isotope tracing identified Nudix hydrolase 5 (NUDT5) as a suppressor of DNPB during purine salvage. NUDT5 ablation allows DNPB to persist in the presence of either native purines or thiopurine drugs; this renders NUDT5-deficient cells insensitive to thiopurine treatment. Surprisingly, this regulation occurs independently of NUDT5s known function in hydrolyzing ADP-ribose to AMP and ribose-5-phosphate. Rather, NUDT5 interacts with phosphoribosyl pyrophosphate amidotransferase (PPAT), the rate-limiting enzyme in DNPB that generates phosphoribosylamine. Upon induction of purine salvage, the PPAT-NUDT5 interaction is required to trigger disassembly of the purinosome, a cytosolic metabolon involved in efficient DNPB. Mutations that disrupt NUDT5s interaction with PPAT but leave its catalytic activity intact permit excessive DNPB during purine salvage, inducing thiopurine resistance. Collectively, our findings identify NUDT5 as a regulator governing the balance between DNPB and purine salvage, underscoring its impact on nucleotide metabolism and efficacy of thiopurine treatment.

biochemistry↗

Metabolic rewiring in fat-depleted Drosophila reveals triglyceride:glycogen crosstalk and identifies cDIP as a new regulator of energy metabolism

Tissues store nutrients as triglyceride (TG) or glycogen at specific ratios, but how these reserves are sensed and balanced remains poorly understood. Here we show that blockage of de novo lipogenesis (DNL) in the Drosophila fat body (FB) triggers a cell autonomous metabolic switch characterized by severe fat depletion and profound glycogen accumulation that supports animal development. Despite lipid loss, Drosophila develop normally but exhibit shortened lifespans and impaired female fecundity. Mechanistically, we identify SREBP-dependent metabolic rewiring that facilitates a switch from TG to glycogen storage, triggered by fatty acid deficiency when DNL is inhibited, and which is rescued by dietary fatty acids. Fat depleted FBs require glycolysis but exhibit blunted mitochondrial metabolism, and no dependence on lactate utilization. Finally, we identify histone acetyltransferases (HATs) Nej and Tip60, which support SREBP activity, as essential for this metabolic switch. Collectively, we propose that in response to DNL deficiency, the fat-depleted FB undergoes a SREBP-mediated TG-to-glycogen metabolic switch preserving organismal development at the cost of reproductive success. Key findingsO_LIFat body-specific FASN1 loss leads to fat-depleted but viable Drosophila that complete their developmental lifecycle by rewiring energy metabolism to store glycogen instead of fat C_LIO_LIFASN1-deficient larvae functionally rely on glycogen synthesis and glycolysis, but not lactate metabolism, and display blunted TCA metabolism C_LIO_LIMetabolic screening reveals a SREBP-dependent TG:glycogen metabolic switch in response to blockage of DNL fatty acid biosynthesis C_LIO_LIHistone acetyltransferases (HATs) Nej and Tip60, and acetyl-CoA synthase, are required for the TG:glycogen metabolic switch C_LI

cell biology↗

Glycosaminoglycan-mediated lipoprotein uptake protects cancer cells from ferroptosis

Lipids are essential for tumours because of their structural, energetic, and signaling roles. While many cancer cells upregulate lipid synthesis, growing evidence suggests that tumours simultaneously intensify the uptake of circulating lipids carried by lipoproteins. Which mechanisms promote the uptake of extracellular lipids, and how this pool of lipids contributes to cancer progression, are poorly understood. Here, using functional genetic screens, we find that lipoprotein uptake confers resistance to lipid peroxidation and ferroptotic cell death. Lipoprotein supplementation robustly inhibits ferroptosis across numerous cancer types. Mechanistically, cancer cells take up lipoproteins through a pathway dependent on sulfated glycosaminoglycans (GAGs) linked to cell-surface proteoglycans. Tumour GAGs are a major determinant of the uptake of both low and high density lipoproteins. Impairment of glycosaminoglycan synthesis or acute degradation of surface GAGs decreases the uptake of lipoproteins, sensitizes cells to ferroptosis and reduces tumour growth in mice. We also find that human clear cell renal cell carcinomas, a distinctively lipid-rich tumour type, display elevated levels of lipoprotein-derived antioxidants and the GAG chondroitin sulfate than non-malignant human kidney. Altogether, our work identifies lipoprotein uptake as an essential anti-ferroptotic mechanism for cancer cells to overcome lipid oxidative stress in vivo, and reveals GAG biosynthesis as an unexpected mediator of this process.

cancer biology↗

PEX39 facilitates the peroxisomal import of PTS2 proteins

Peroxisomes are metabolic organelles essential for human health. Defects in peroxisomal biogenesis proteins (peroxins/PEXs) cause devastating disease. PEX7 binds newly synthesized proteins containing a type 2 peroxisomal targeting signal (PTS2) to enable their import from the cytosol into peroxisomes, although many aspects of this import pathway remain enigmatic. Utilizing in vitro assays, yeast, and human cells, we show that PEX39, a previously uncharacterized protein, is a cytosolic peroxin that facilitates PTS2-protein import by binding PEX7 and stabilizing its interaction with PTS2 cargo. PEX39 and PEX13, a peroxisomal membrane translocon protein, both possess a KPWE motif necessary for PEX7 binding. Sequential binding of PEX7 to this motif in PEX39 and PEX13 provides a novel paradigm for how PTS2 cargo engage the translocation machinery. Collectively, our work uncovers an ancient and functionally important relationship among PEX39, PEX7, and PEX13, offering insights that will advance our understanding of peroxisomal biogenesis and disease.

cell biology↗