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Laboratory-accelerated aging experiments conducted to examine the depletion of antioxidant from a geomembrane (GM) underlain by a geosynthetic clay liner (GCL) are described. Three different 'protection' layers between the GM and overlying gravel and leachate are examined: (1) A traditional nonwoven geotextile (GT); (2) a GT-GCL; and (3) a GT-sand-GT layer. The GT-GCL protection layer gives an antioxidant depletion rate 0.59 to 0.66 times slower than the GT layer alone. The GT-sand-GT layer gives depletion rates 0.72-0.75 times that of the conventional GT alone. Based on Arrhenius modeling, the time required for depletion of antioxidants at 35[degrees]C is estimated to be 65 years for a GM with a GT-GCL protection layer, 50 years for a GT-sand-GT layer, and 40 years for a conventional GT protection layer. These times are all significantly greater than the depletion time for GM immersed in leachate (10 years) for the geomembrane tested. CE Database subject headings: Durability; Geomembranes; Landfills; Liners; Service life; Temperature.

The results of two series of accelerated aging tests are reported. Both series of tests were conducted at temperatures of 85, 70, 55, and 26[degrees]C over a period of about 3 years. In the simulated liner series, the top of the geomembrane was covered with a geotextile (protection) layer that was exposed to simulated municipal solid waste (MSW) landfill leachate while the bottom of the geomembrane was in contact with a hydrated geosynthetic clay liner. In the immersion series, the geomembrane was immersed in the simulated MSW leachate, and hence, both sides were exposed to leachate. The results from oxidative induction time tests indicate that the antioxidant depletion is about 2.2-4.8 times faster for the leachate immersed geomembrane than for geomembrane in a composite liner. The higher rates are attributed to the higher extraction of antioxidants from two sides of the geomembrane immersed in leachate. The measured antioxidant depletion rates are extrapolated to a range of temperatures (0-60[degrees]C) using Arrhenius modeling. At a liner temperature of 35[degrees]C, the calculated time for the depletion of antioxidants is about 40 years for a geomembrane in a composite liner compared to 10 years if it is simply immersed in leachate. These tests suggest that to obtain realistic estimates of geomembrane service life one needs data from tests that simulate the expected field conditions and that prediction based on immersion tests may underestimate the service life. DOI: 10.1061/(ASCE)1090-0241(2008)134:1(68) CE Database subject headings: Geomembranes; Durability; Liners; Landfills; Service life; Temperature; Composite materials.

Ionotropic receptors (IRs), which form ion channels, can be categorized into conserved 'antennal IRs', which define the first olfactory receptor family of insects, and species-specific 'divergent IRs', which are expressed in gustatory receptor neurones. These receptors are located primarily in cell bodies and dendrites, and are highly enriched in the tips of the dendritic terminals that convey sensory information to higher brain centres. Antennal IRs play important roles in odour and thermosensation, whereas divergent IRs are involved in other important biological processes such as taste sensation. Some IRs are known to play specific biological roles in the perception of various molecules; however, many of their functions have not yet been defined. Although progress has been made in this field, many functions and mechanisms of these receptors remain unknown. In this review, we provide a comprehensive summary of the current state of knowledge in this field. [ABSTRACT FROM AUTHOR]

It is well established that DNA Damage Regulated Autophagy Modulator 1 (DRAM1), a lysosomal protein and a target of p53, participates in autophagy. The cellular functions of DRAM1 beyond autophagy remain elusive. Here, we show p53-dependent upregulation of DRAM1 in mitochondrial damage-induced Parkinson's disease (PD) models and exacerbation of disease phenotypes by DRAM1. We find that the lysosomal location of DRAM1 relies on its intact structure including the cytosol-facing C-terminal domain. Excess DRAM1 disrupts endoplasmic reticulum (ER) structure, triggers ER stress, and induces protective ER-phagy. Mechanistically, DRAM1 interacts with stromal interacting molecule 1 (STIM1) to tether lysosomes to the ER and perturb STIM1 function in maintaining intracellular calcium homeostasis. STIM1 overexpression promotes cellular health by restoring calcium homeostasis, ER stress response, ER-phagy, and AMP-activated protein kinase (AMPK)-Unc-51 like autophagy activating kinase 1 (ULK1) signaling in cells with excess DRAM1. Thus, by promoting organelle contact between lysosomes and the ER, DRAM1 modulates ER structure and function and cell survival under stress. Our results suggest that DRAM1 as a lysosomal protein performs diverse roles in cellular homeostasis and stress response. These findings may have significant implications for our understanding of the role of the p53/DRAM1 axis in human diseases, from cancer to neurodegenerative diseases., Competing Interests: Competing interests statement:The authors declare no competing interest.

Ribosome-associated quality control (RQC) monitors ribosomes for aberrant translation. While the role of RQC in neurodegenerative disease is beginning to be appreciated, its involvement in cancer is understudied. Here, we show a positive correlation between RQC proteins ABCE1 and ZNF598 and high-grade muscle-invasive bladder cancer. Translational stalling by the inhibitor emetine (EME) leads to increased mitochondrial localization of RQC factors including ABCE1, ZNF598, and NEMF, which are continuously imported into mitochondria facilitated by increased mitochondrial membrane potential caused by EME. This reduces the availability of these factors in the cytosol, compromising the effectiveness of RQC in handling stalled ribosomes in the cytosol and those associated with the mitochondrial outer membrane (MOM). Imported RQC factors form aggregates inside the mitochondria in a process we term stalling-induced mitochondrial stress (SIMS). ABCE1 plays a crucial role in maintaining mitochondrial health during SIMS. Notably, cancer stem cells (CSCs) exhibit increased expression of ABCE1 and consequently are more resistant to EME-induced mitochondrial dysfunction. This points to a potential mechanism of drug resistance by CSCs. Our study highlights the significance of mitochondrial entrapment of RQC factors such as ABCE1 in determining the fate of cancer cells versus CSCs. Targeting ABCE1 or other RQC factors in translational inhibition cancer therapy may help overcome drug resistance., Competing Interests: Additional Declarations: There is NO Competing Interest. No potential confl icts of interest weredisclosed by the other authors. DISCLOSURE OF POTENTIAL CONFLICTS OF INTEREST: No potential conflicts of interest were disclosed by the other authors.

Myc is a major driver of tumor initiation, progression, and maintenance. Up-regulation of Myc protein level rather than acquisition of neomorphic properties appears to underlie most Myc-driven cancers. Cellular mechanisms governing Myc expression remain incompletely defined. In this study, we show that ribosome-associated quality control (RQC) plays a critical role in maintaining Myc protein level. Ribosomes stall during the synthesis of the N-terminal portion of cMyc, generating aberrant cMyc species and necessitating deployment of the early RQC factor ZNF598 to handle translational stress and restore cMyc translation. ZNF598 expression is up-regulated in human glioblastoma (GBM), and its expression positively correlates with that of cMyc. ZNF598 knockdown inhibits human GBM neurosphere formation in cell culture and Myc-dependent tumor growth in vivo in Drosophila . Intriguingly, the SARS-COV-2-encoded translational regulator Nsp1 impinges on ZNF598 to restrain cMyc translation and consequently cMyc-dependent cancer growth. Remarkably, Nsp1 exhibits synthetic toxicity with the translation and RQC-related factor ATP-binding cassette subfamily E member 1, which, despite its normally positive correlation with cMyc in cancer cells, is co-opted by Nsp1 to down-regulate cMyc and inhibit tumor growth. Ribosome stalling during c-myc translation thus offers actionable cancer cell vulnerability., (© The Author(s) 2024. Published by Oxford University Press on behalf of National Academy of Sciences.)

In 2023, Nepal faced its second largest dengue outbreak ever, following a record-breaking number of dengue cases in 2022, characterized by the expansion of infections into areas of higher altitudes. However, the characteristics of the 2023 circulating dengue virus (DENV) and the vector density remain poorly understood. Therefore, we performed DENV serotyping, clinical and laboratory assessment, and entomological analysis of the 2023 outbreak in central Nepal. A total of 396 fever cases in Dhading hospital suspected of being DENV positive were enrolled, and blood samples were collected and tested by different techniques including PCR. Of these, 278 (70.2%) had confirmed DENV infection. Multiple serotypes (DENV-1, -2, and -3) were detected. DENV-2 (97.5%) re-emerged after six years in Dhading while DENV-3 was identified for the first time. Dengue inpatients had significantly higher frequency of anorexia, myalgia, rash, diarrhea, nausea, vomiting, abdominal pain, and thrombocytopenia ( p < 0.05). In this area, Aedes mosquitoes largely predominated (90.7%) with the majority being A. aegypti (60.7%). We also found high levels of Aedes index (20.0%) and container index (16.7%). We confirmed multiple DENV serotype circulation with serotype re-emergence and new serotype introduction, and high vector density in 2023. These findings call for the urgent initiation and scaling up of DENV molecular surveillance in human and mosquito populations for dengue control and prevention in Nepal.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by dysregulation of the expression and processing of the amyloid precursor protein (APP). Protein quality control systems are dedicated to remove faulty and deleterious proteins to maintain cellular protein homeostasis (proteostasis). Identidying mechanisms underlying APP protein regulation is crucial for understanding AD pathogenesis. However, the factors and associated molecular mechanisms regulating APP protein quality control remain poorly defined. In this study, we show that mutant APP with its mitochondrial-targeting sequence ablated exhibited predominant endoplasmic reticulum (ER) distribution and led to aberrant ER morphology, deficits in locomotor activity, and shortened lifespan. We searched for regulators that could counteract the toxicity caused by the ectopic expression of this mutant APP. Genetic removal of the ribosome-associated quality control (RQC) factor RACK1 resulted in reduced levels of ectopically expressed mutant APP. By contrast, gain of RACK1 function increased mutant APP level. Additionally, overexpression of the ER stress regulator (IRE1) resulted in reduced levels of ectopically expressed mutant APP. Mechanistically, the RQC related ATPase VCP/p97 and the E3 ubiquitin ligase Hrd1 were required for the reduction of mutant APP level by IRE1. These factors also regulated the expression and toxicity of ectopically expressed wild type APP, supporting their relevance to APP biology. Our results reveal functions of RACK1 and IRE1 in regulating the quality control of APP homeostasis and mitigating its pathogenic effects, with implications for the understanding and treatment of AD., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Translational control exerts immediate effect on the composition, abundance, and integrity of the proteome. Ribosome-associated quality control (RQC) handles ribosomes stalled at the elongation and termination steps of translation, with ZNF598 in mammals and Hel2 in yeast serving as key sensors of translation stalling and coordinators of downstream resolution of collided ribosomes, termination of stalled translation, and removal of faulty translation products. The physiological regulation of RQC in general and ZNF598 in particular in multicellular settings is underexplored. Here we show that ZNF598 undergoes regulatory K63-linked ubiquitination in a CNOT4-dependent manner and is upregulated upon mitochondrial stresses in mammalian cells and Drosophila. ZNF598 promotes resolution of stalled ribosomes and protects against mitochondrial stress in a ubiquitination-dependent fashion. In Drosophila models of neurodegenerative diseases and patient cells, ZNF598 overexpression aborts stalled translation of mitochondrial outer membrane-associated mRNAs, removes faulty translation products causal of disease, and improves mitochondrial and tissue health. These results shed lights on the regulation of ZNF598 and its functional role in mitochondrial and tissue homeostasis., (© 2024. The Author(s).)

Background: The most common differential diagnoses of microcytic hypochromic anaemia are iron deficiency anaemia and beta thalassemia. Globally, thalassemia affects approximately 4.4 out of every 10,000 live births whereas iron deficiency anaemia comprises half of all anaemia worldwide as per world health organization. The definitive diagnosis of beta thalassemia trait and iron deficiency anaemia requires haemoglobin analysis and iron studies respectively, which are not possible to perform in all suspected cases especially in resource limited settings. The study aims to evaluate the reliability of mentzer index in differentiating beta thalassemia trait from iron deficiency anaemia., Methods: This was a cross sectional, observational study done on 59 patients each of beta thalassemia trait and iron deficiency anaemia from August 2019 to July 2020. Patients who were found to be having iron deficiency anaemia diagnosed by iron studies and beta thalassemia trait diagnosed by Hb electrophoresis were enrolled in the study using simple random sampling technique., Results: Mentzer index correctly identified 95.76% of overall patients. Area under receiver operating characteristic curve was 0.993 (95% CI, 0.985-1.002, p<0.001). For beta thalassemia trait, mentzer index showed a sensitivity of 93.2%, specificity of 98.3%, positive predictive value of 98.2%, negative predictive value of 93.5%; while for iron deficiency anaemia, sensitivity of 98.3%, specificity of 93.2%, positive predictive value of 93.5% and negative predictive value of 98.2%. Youden's index was 91.5., Conclusions: The findings of the present study make mentzer index a reliable screening method, especially in a resource poor setting, like Nepal. Further confirmation by gold standard tests is recommended.

Nipah virus (NiV) is a zoonotic, single-stranded RNA virus from the family Paramyxoviridae, genus Henipavirus. NiV is a biosafety-level-4 pathogen that is mostly spread by Pteropus species, which serve as its natural reservoir host. NiV is one of the major public health challenges in South and South East Asia. However, few molecular studies have been conducted to characterise NiV in a specific region. The main objective of this review is to understand the epidemiology, pathogenesis, molecular surveillance, transmission dynamics, genetic diversity, reservoir host, clinical characteristics, and phylogenetics of NiV. South and South East Asian nations have experienced NiV outbreaks. Phylogenetic analysis confirmed that two primary clades of NiV are in circulation. In humans, NiV causes severe respiratory illness and/or deadly encephalitis. NiV is mainly diagnosed by ELISA along with PCR. Therefore, we recommend that the governments of the region support the One Health approach to reducing the risk of zoonotic disease transmission in their respective countries., (© 2023. Japanese Society of Tropical Medicine.)

Background and Aims: Unlike classically described polycythemia, anemia is found to be more prevalent in patients with chronic obstructive pulmonary disease (COPD). Anemia increases the cost of hospital stay and causes an increased risk of adverse outcomes including death in COPD patients. This study was done to find the prevalence of anemia in COPD patients, the factors associated, and the outcomes of anemic COPD., Methods: It was a quantitative, descriptive-analytical, and cross-sectional study conducted in Tribhuvan University Teaching Hospital's medical wards and the Emergency Room from September 2019 to September 2020. A simple random sampling method was used. Clinical information was obtained, and patients were followed up 3 months after discharge to document the number of exacerbations and deaths if present., Results: The patients in our study had a mean age of 70.80 ± 11.16 years. Most were female. Most (85.5%) had a history of exposure to firewood smoke. Twenty-three percent of the patients had anemia and these patients had significantly greater mortality 3 months postdischarge. Middle-old and old were more likely to have anemia with odds ratio (OR) of 2.55 (confidence interval [CI]: 0.48-13.5) and 13.6 (CI: 1.12-24.2), respectively. Current smokers had less likelihood of having anemia (OR: 0.05, CI: 0.006-0.49). Multivariate analysis showed that age, sex, and smoking status were significant determinants of anemia in COPD. There was no association between anemia and duration of hospital stay. However, mortality was higher at 3 months in COPD patients with anemia ( p  < 0.001)., Conclusion: In COPD patients, anemia is prevalent comorbidity that is significantly linked to higher mortality but not to exacerbations. It is unknown, though, if treating anemia in COPD patients will affect the patient's outcome. Additional research in this area may be possible., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors. Health Science Reports published by Wiley Periodicals LLC.)

Chylous ascites is an uncommon condition of accumulation of milky fluid rich in lymph and chylomicrons in the peritoneal cavity. Post-surgical complications following dissection near the base of the mesentery, retroperitoneum, or near the cisterna chyli, malignancies (e.g., pancreatic adenocarcinomas, lymphoma, gastric carcinoma), cirrhosis, and trauma are the prime causes of chylous ascites. Here we report a rare case of chylous ascites following clearance of isolated paraaortic nodal recurrence in a 28-year-old female with dysgerminoma of ovary. The patient developed chylous ascites on the fifth day following surgery, which was confirmed by an increased drain fluid triglyceride level. She was managed conservatively with dietary modification including a high-protein and carbohydrate but low-fat-based diet mainly containing medium-chain fatty acids. Subsequently, she recovered from chylous ascites on the sixteenth day, completed second line chemotherapy, and is now doing well., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Mechanisms underlying the depletion of NAD + and accumulation of reactive oxygen species (ROS) in aging and age-related disorders remain poorly defined. We show that reverse electron transfer (RET) at mitochondrial complex I, which causes increased ROS production and NAD + to NADH conversion and thus lowered NAD + /NADH ratio, is active during aging. Genetic or pharmacological inhibition of RET decreases ROS production and increases NAD + /NADH ratio, extending the lifespan of normal flies. The lifespan-extending effect of RET inhibition is dependent on NAD + -dependent Sirtuin, highlighting the importance of NAD + /NADH rebalance, and on longevity-associated Foxo and autophagy pathways. RET and RET-induced ROS and NAD + /NADH ratio changes are prominent in human induced pluripotent stem cell (iPSC) model and fly models of Alzheimer's disease (AD). Genetic or pharmacological inhibition of RET prevents the accumulation of faulty translation products resulting from inadequate ribosome-mediated quality control, rescues relevant disease phenotypes, and extends the lifespan of Drosophila and mouse AD models. Deregulated RET is therefore a conserved feature of aging, and inhibition of RET may open new therapeutic opportunities in the context of aging and age-related diseases including AD., (© 2023 The Authors.)

Expansion of G4C2 hexanucleotide repeats in the chromosome 9 ORF 72 (C9ORF72) gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS) with frontotemporal dementia (C9-ALS/FTD). Dipeptide repeats generated by unconventional translation, especially the R-containing poly(GR), have been implicated in C9-ALS/FTD pathogenesis. Mutations in other genes, including TAR DNA-binding protein 43 KD (TDP-43), fused in sarcoma (FUS), and valosin-containing protein, have also been linked to ALS/FTD, and upregulation of amyloid precursor protein (APP) is observed at the early stage of ALS and FTD. Fundamental questions remain as to the relationships between these ALS/FTD genes and whether they converge on similar cellular pathways. Here, using biochemical, cell biological, and genetic analyses in Drosophila disease models, patient-derived fibroblasts, and mammalian cell culture, we show that mechanistic target of rapamycin complex 2 (mTORC2)/AKT signaling is activated by APP, TDP-43, and FUS and that mTORC2/AKT and its downstream target valosin-containing protein mediate the effect of APP, TDP-43, and FUS on the quality control of C9-ALS/FTD-associated poly(GR) translation. We also find that poly(GR) expression results in reduction of global translation and that the coexpression of APP, TDP-43, and FUS results in further reduction of global translation, presumably through the GCN2/eIF2α-integrated stress response pathway. Together, our results implicate mTORC2/AKT signaling and GCN2/eIF2α-integrated stress response as common signaling pathways underlying ALS/FTD pathogenesis., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The largest dengue outbreak in the history of Nepal occurred in 2022, with a significant number of casualties. It affected all 77 districts, with the nation's capital, Kathmandu (altitude 1300 m), being the hardest hit. However, the molecular epidemiology of this outbreak, including the dengue virus (DENV) serotype(s) responsible for this epidemic, remain unknown. Here, we report the epidemic trends, clinico-laboratory features, and virus serotypes and their viral load profiles that are associated with this outbreak in Nepal. Dengue-suspected febrile patients were investigated by routine laboratory, serological, and molecular tools, including a real-time quantitative polymerase chain reaction (qRT-PCR). Of the 538 dengue-suspected patients enrolled, 401 (74.5%) were diagnosed with dengue. Among these dengue cases, 129 (32.2%) patients who required hospital admission had significant associations with myalgia, rash, diarrhea, retro-orbital pain, bleeding, and abdominal pain. DENV-1, -2, and -3 were identified during the 2022 epidemic, with a predominance of DENV-1 (57.1%) and DENV-3 (32.1%), exhibiting a new serotype addition. We found that multiple serotypes circulated in 2022, with a higher frequency of hospitalizations, more severe dengue, and more deaths than in the past. Therefore, precise mapping of dengue and other related infections through integrated disease surveillance, evaluation of the dynamics of population-level immunity and virus evolution should be the urgent plans of action for evidence-based policy-making for dengue control and prevention in the country.

High levels of trace metals such as copper (Cu) can affect water quality and induce toxic effects on living organisms in aquatic ecosystems. This research assesses the potential capacity for Cu phytofiltration by three emergent macrophytes from Cu-contaminated sediments and water containing five concentrations of Cu (0, 50, 100, 150, and 200 µM). We conducted a greenhouse study using semi-hydroponic and hydroponic experimental conditions to simulate a natural wetland system. We selected three plant types that were collected in Quebec (Canada): native Typha latifolia , and native and, exotic Phragmites australis . Under semi-hydroponic, the responses indicated an almost 3-fold higher mean root Cu-accumulation from Cu-0 to Cu-Sediment (80.3-226.1 mg kg -1 ) and an 8.6-fold increase (122.2-1045.5 mg kg -1 ) for Cu-0 to Cu-200 µM under hydroponic conditions, resulting in Cu translocation < 1 and BCF >1 under both conditions. We found an inverse correlation between increasing doses of Cu with mean aboveground and belowground biomass together with height, and root length of selected plants under hydroponic conditions. Our results indicate that these wetland macrophytes could be useful in heavy-metal removal from Cu-contaminated sediments and Cu-enriched water.

An overarching goal of aging and age-related neurodegenerative disease research is to discover effective therapeutic strategies applicable to a broad spectrum of neurodegenerative diseases. Little is known about the extent to which targetable pathogenic mechanisms are shared among these seemingly diverse diseases. Translational control is critical for maintaining proteostasis during aging. Gaining control of the translation machinery is also crucial in the battle between viruses and their hosts. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the ongoing COVID-19 pandemic. Here, we show that overexpression of SARS-CoV-2-encoded nonstructural protein 1 (Nsp1) robustly rescued neuromuscular degeneration and behavioral phenotypes in Drosophila models of Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. These diseases share a common mechanism: the accumulation of aberrant protein species due to the stalling and collision of translating ribosomes, leading to proteostasis failure. Our genetic and biochemical analyses revealed that Nsp1 acted in a multipronged manner to resolve collided ribosomes, abort stalled translation, and remove faulty translation products causative of disease in these models, at least in part through the ribosome recycling factor ABCE1, ribosome-associated quality-control factors, autophagy, and AKT signaling. Nsp1 exhibited exquisite specificity in its action, as it did not modify other neurodegenerative conditions not known to be associated with ribosome stalling. These findings uncover a previously unrecognized mechanism of Nsp1 in manipulating host translation, which can be leveraged for combating age-related neurodegenerative diseases that are affecting millions of people worldwide and currently without effective treatment.

Folded proteins are assumed to be built upon fixed scaffolds of secondary structure, α-helices and β-sheets. Experimentally determined structures of >58,000 non-redundant proteins support this assumption, though it has recently been challenged by ~100 fold-switching proteins. Though ostensibly rare, these proteins raise the question of how many uncharacterized proteins have shapeshifting-rather than fixed-secondary structures. Here, we use a comparative sequence-based approach to predict fold switching in the universally conserved NusG transcription factor family, one member of which has a 50-residue regulatory subunit experimentally shown to switch between α-helical and β-sheet folds. Our approach predicts that 24% of sequences in this family undergo similar α-helix ⇌ β-sheet transitions. While these predictions cannot be reproduced by other state-of-the-art computational methods, they are confirmed by circular dichroism and nuclear magnetic resonance spectroscopy for 10 out of 10 sequence-diverse variants. This work suggests that fold switching may be a pervasive mechanism of transcriptional regulation in all kingdoms of life., (© 2022. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Metabolic flexibility is a hallmark of many cancers where mitochondrial respiration is critically involved, but the molecular underpinning of mitochondrial control of cancer metabolic reprogramming is poorly understood. Here, we show that reverse electron transfer (RET) through respiratory chain complex I (RC-I) is particularly active in brain cancer stem cells (CSCs). Although RET generates ROS, NAD + /NADH ratio turns out to be key in mediating RET effect on CSC proliferation, in part through the NAD + -dependent Sirtuin. Mechanistically, Notch acts in an unconventional manner to regulate RET by interacting with specific RC-I proteins containing electron-transporting Fe-S clusters and NAD(H)-binding sites. Genetic and pharmacological interference of Notch-mediated RET inhibited CSC growth in Drosophila brain tumor and mouse glioblastoma multiforme (GBM) models. Our results identify Notch as a regulator of RET and RET-induced NAD + /NADH balance, a critical mechanism of metabolic reprogramming and a metabolic vulnerability of cancer that may be exploited for therapeutic purposes., Competing Interests: Declaration of interests B.L. is a scientific founder of Cerepeut, a member of Cerepeut’s scientific advisory board, and an inventor on patents related to CPT2008., (Copyright © 2021 Elsevier Inc. All rights reserved.)