The oxidative pentose phosphate pathway: structure and organisation

Basil chilling injury: Oxidative stress or energy depletion?

Basil (Ocimum basilicum L.) is susceptible to chilling injury (CI), leading to significant postharvest quality loss. This research aimed to identify key metabolites involved in CI of basil during cold storage to better understand the underlying mechanisms. Metabolite profiles of basil leaves stored at 4 and 12 °C for up to 12 days were quantified by 1H NMR and GC-MS. At 4 °C shelf life was reduced due to CI. At 4 °C, several osmoprotectants, including proline, gamma-aminobutyric acid, trehalose and myo-inositol increased, whereas antioxidants like ascorbic acid and rosmarinic acid decreased; the latter likely due to scavenging reactive oxygen species. During chilling stress, antioxidant defence pathways were upregulated and carbohydrate related energy pathways were downregulated. We suggest that CI in basil associates with redirection of carbohydrate flux towards antioxidant defence systems, leading to energy depletion. This energy depletion is hypothesized as a primary trigger for CI in postharvest basil.

OsLC1, a transaldolase, regulates cell patterning and leaf morphology through modulation of secondary metabolism

Leaf morphogenesis is a crucial process in plants that governs essential physiological functions such as photosynthesis and transpiration. Despite significant advances in understanding leaf development, the mechanism of intricate cellular patterning remains elusive. We characterize the OsLC1 mutant, which displays a curly leaf phenotype alongside reductions in plant height and tiller number, which are indicative of multiple morphological abnormalities. Through map-based cloning, we identified OsLC1 as encoding a transaldolase (TA) protein, whose genetic variations in OsLC1 lead to the disruptions of cell patterning across the vasculature, bundle sheath cells, mesophyll, stomata, bulliform cells and sclerenchyma cells. OsLC1 exhibited TA activity and modulated metabolic flux to the shikimic pathway, thereby affecting phenylpropanoid metabolism. This regulation influenced lignin and flavonoid biosynthesis, ultimately modulating cellular pattern formation through perturbations to flavonoid-mediated auxin or lignin homeostasis. Notably, loss of OsLC1 function led to a reduction in leaf water status, which, along with abnormal cellular patterns in oslc1, caused leaf curling. Overall, our findings provide insights into the regulatory mechanisms underlying cell patterning in the leaf and offer valuable perspectives on leaf morphogenesis in rice.

Spatiotemporal expression patterns and RNA interference efficiency of key diapause genes in Lymantria dispar-Investigating the heritability of RNA interference effects for pest biocontrol

The spongy moth (Lymantria dispar Linnaeus), a major quarantine pest, relies on diapause as a key survival strategy. This study examined the temporal and spatial expression of four diapause-associated genes, LdGCLC, LdGLUD1_2, LdIDH1, and LdIDH2. Using fluorescence in situ hybridization and qPCR, their expression was analyzed across developmental stages and tissues. Additionally, RNA interference (RNAi) via microinjection and immersion was employed to systematically silence these genes. The results revealed that (1) all four genes were expressed in the brain; (2) dsRNA microinjection reduced target gene expression in larvae, with FISH showing a decrease in fluorescence intensity; (3) immersing eggs in dsRNA solution significantly lowered target gene expression, diapause hormone and ecdysone levels, along with a notable reduction in hatchability; (4) pre-immersion eggs in 4.4 M HCl at room temperature for 5 min before bacterial immersion significantly enhanced RNAi efficiency; and (5) maternal dsRNA microinjection decreased target gene expression, diapause hormone and ecdysone levels in offspring eggs, confirming transgenerational RNAi. These findings underscore RNAi's potential for heritable gene silencing in pest control.

Screening and characterization of thermostable xylose isomerase from Rhodothermus marinus for erythrose production from one-carbon source

Four-carbon (C4) sugars, which rarely exist in nature, usually have various biological functions and serve as building units for pharmaceutical agents. For example, erythrose possesses various pharmacological activities. Although several iso/epimerases have a catalytic function on C5/C6 sugars, only a few studies have demonstrated the enzymatic iso/epimerization of C4 sugars. In this work, we presented a xylose isomerase from Rhodothermus marinus possessing isomerization activity toward C4 l-erythrulose. This enzyme showed higher affinity and catalytic efficiency toward l-erythrulose than d-fructose and d-xylulose. Its specific activity reached 24.2 U/mg under optimal reaction conditions, and its half-life was over 8 days at 50 ℃. Demonstration of this enzyme under 833 mM of L-erythrulose gave 130 mM L-erythrose with a conversion yield of 15.6 %. On the basis of this beneficial enzyme, we further designed a multienzyme system and presented a one-pot cascade process for the synthesis of l-erythrose from low-cost, one-carbon formaldehyde (FALD) as the sole feedstock. Given that FALD can be derived from CO2 electrocatalysis or methanol oxidization, l-erythrose synthesis can be realized from methanol and even CO2. l-erythrose can further function as feedstock for synthesizing other high-carbon sugars by coupling enzymatic aldol condensation and reduction reactions.

Mechanistic understanding of the toxic effects of tri-n-butyl phosphate (TnBP) and tricresyl phosphate (TCP) to Escherichia coli: Evidence from alterations in biomarker expression and perturbations of the metabolic network

Tri-n-butyl phosphate (TnBP) and tricresyl phosphate (TCP), emerging flame retardants and plasticizers, have garnered increasing attention due to their potential risks to ecosystem. A few researches regarding the toxicological mechanisms of TnBP and TCP had been performed, while molecular-level toxic effects of them and metabolic response using microbial models are the lack of relevant investigation. Thus, we investigated the cytotoxicity, oxidative stress response, and metabolic response in E. coli exposed to TnBP and TCP. Exposure to them significantly increased the activities of antioxidant enzymes, indicating activation of the antioxidant defense system. Excessive accumulation of reactive oxygen species (ROS) triggered various biological events, including a reduction in membrane potential (MP), decrease of adenosine triphosphatase (ATPase) activity, and increased malondialdehyde (MDA) content. These findings suggested that oxidative damage compromised membrane proteins function, membrane stability, and intracellular homeostasis. GC-MS and LC-MS-based metabolomics analyses revealed that TnBP and TCP strongly disrupted multiple metabolic pathways, including carbohydrate metabolism, nucleotide metabolism, lipid metabolism, beta-alanine metabolism, pyruvate metabolism and oxidative phosphorylation. These disruptions highlighted the inhibitory effects on molecular functions and metabolic processes. Notably, lipids biomarkers e.g., PC(11:0/16:0), PA(17:1(9Z)/18:2(9Z,12Z)), PE(17:0/14:1(9Z)), and LysoPE(0:0/18:1(11Z)) were significantly altered, verifying that the regulation of lipid-associated metabolite synthesis plays a protective role in maintaining cellular membrane function. In summary, this study enhances our understanding of TnBP and TCP toxicity in E. coli, providing novel insights into their toxicological mechanisms at molecular and network levels. These findings underscore the ecological risks posed by organophosphate flame retardants in aquatic ecosystem.

Molecular Mechanisms Underlying the Impacts of Available-Iron Levels on the Accumulation and Translocation of 6:2 Chlorinated Polyfluoroalkyl Ether Sulfonate in Soybean (Glycine max L. Merrill)

Soil available-iron (Fe) is crucial for various physiological properties and processes in plants, particularly those related to the accumulation and translocation of per- and polyfluoroalkyl substances (PFAS). However, the mechanisms underlying the impact of available-Fe levels on PFAS accumulation and translocation in plants remain unclear. In this study, we investigated the impacts of available-Fe levels on the accumulation of an emerging PFAS, 6:2 chlorinated polyfluoroalkyl ether sulfonate (6:2 Cl-PFESA), in soybean, a typical dicot, through hydroponic experiments. Interestingly, Fe deficiency significantly enhanced soybean root volume, surface area, root tip count, and lipid content, thus favoring 6:2 Cl-PFESA adsorption on the root epidermis. However, its absorption and translocation to aboveground tissues were markedly suppressed due to significantly reduced transpiration rate and soluble protein content induced by Fe deficiency. Conversely, although excessive available-Fe also inhibited transpiration, it notably increased root membrane permeability and soluble protein content in aboveground tissues, thus greatly facilitating the absorption and translocation of 6:2 Cl-PFESA within soybeans. These findings demonstrate that appropriate Fe application in agricultural soils is essential to promote the growth of dicot crops and mitigate the potential ecological risks associated with the accumulation of 6:2 Cl-PFESA in the aboveground tissues of soybeans.

Physiological and metabolomic insights into molecular mechanisms of root sensitivity to zinc toxicity in rice (Oryza sativa L.)

Zinc (Zn) is an essential micronutrient for plants, but excessive concentrations induce cytotoxicity. As one of the world's primary crops, rice's response mechanisms to Zn toxicity remain poorly understood. In this study, we characterized a rice mutant, NG3-6, which exhibited enhanced sensitivity to Zn toxicity compared to the wild type (WT). At Zn concentrations of 40 μM and above, NG3-6 displayed severe toxicity symptoms, including reduced primary root length, plant height, and dry weight, whereas the WT plants maintained normal growth until Zn concentrations exceeded 400 μM. The mutant demonstrated a higher Zn uptake capacity in roots, leading to increased Zn accumulation across all tissues. This higher Zn accumulation was correlated with elevated reactive oxygen species (ROS) production. Zn toxicity induced the accumulation of oxidative stress-related metabolites, such as L-proline, glutathione, and water-soluble sugars, in both the mutant and WT. However, NG3-6 showed distinct metabolic alterations in response to high Zn treatment, including significant accumulation of certain metabolites associated with the pentose phosphate pathway, amine biosynthesis, and benzoic acid-related pathways, concurrent with reduced flavonoid biosynthesis. These findings advance our understanding of the molecular mechanisms underlying root adaptive strategies to Zn toxicity in plants.

Physiological and molecular responses of tropical Seagrass Enhalus acoroides exposed to simultaneous high temperature and hypoxia stress

High temperature and hypoxia pose significant threats to coastal ecosystems, often co-occurring and intensifying damage to seagrass meadows. While the independent effects of these stresses have been extensively documented, their combined impact on seagrasses remains underexplored. This study investigates the effects of high temperature and hypoxia on Enhalus acoroides, a dominant tropical seagrass. Results indicated that E. acoroides could tolerate high temperature (35 °C) and hypoxia (2.65 mg L-1) individually for 24 h. However, exposure to both stresses simultaneously led to severe, irreversible physiological damage, highlighting a synergistic effect that surpassed the additive impact of each stressor alone. Combined stresses markedly impaired PSII, reduced photosynthetic rate and chlorophyll content, alongside elevated oxidative stress. Transcriptomic analysis indicated that high temperature intensified metabolic stress, while oxygen deficiency forced a shift from aerobic to anaerobic respiration, resulting in energy deficits. Furthermore, the lack of oxygen caused the accumulation of electrons, which triggered excessive production of reactive oxygen species. Despite the antioxidant enzyme system's active response, it was unable to mitigate the overwhelming oxidative stress, leading to irreversible oxidative damage. The above results suggested that in the context of global warming and eutrophication, the combined effects of high temperature and hypoxia may accelerate the degradation of seagrass meadows at a far greater rate than previously anticipated.

Cytoplasmic G6PDs modulate callus formation in Arabidopsis root explants through regulation of very-long-chain fatty acids accumulation

Glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme in the pentose phosphate pathway, impacts cancer cell proliferation and plant stress responses. However, its role in plant cell dedifferentiation and callus formation is not well understood. This study explores the function of cytoplasmic G6PD isoforms in Arabidopsis pericycle cell reprogramming into callus by employing a suite of mutant analyses, qRT-PCR, and GC-MS. Our findings demonstrate that g6pd5/6 double mutants exhibit enhanced callus formation compared to wild-type and single mutants, implicating cytoplasmic G6PDs as negative regulators of callus development. The double mutant showed reduced NADPH levels and increased expression of very-long-chain fatty acid (VLCFA) biosynthesis genes and the VLCFA-downstream gene Aberrant Lateral Root Formation 4 (ALF4) on callus-inducing medium (CIM). Notably, VLCFA concentrations were decreased in g6pd5/6 mutants, and supplementation of VLCFA reduced callus area. Additionally, callus formation in the alf4/g6pd5/6 triple mutant aligned with wild-type, suggesting a redundant inhibitory function of G6PD5 and G6PD6 in the regulation of VLCFA accumulation and related signaling. Contrasting with their roles in cancer cell proliferation, our study unveils novel insights into the G6PD signaling pathway, highlighting its unique function in negatively regulating plant callus formation.

Plastidial thioredoxin-like proteins are essential for normal embryogenesis and seed development in Arabidopsis thaliana

Thiol/disulfide-based redox regulation is a key mechanism for modulating protein functions in response to changes in cellular redox status. Two thioredoxin (Trx)-like proteins [atypical Cys His-rich Trx (ACHT) and Trx-like2 (TrxL2)] have been identified as crucial for oxidizing and deactivating several chloroplast enzymes during light-to-dark transitions; however, their roles remain to be fully understood. In this study, we investigated the functions of Trx-like proteins in seed development. Using the CRISPR/Cas9 system, we generated an Arabidopsis quadruple mutant defective in ACHT1, ACHT2, TrxL2.1, and TrxL2.2 (acht/trxl2). This mutant showed increased seed lethality prior to maturation, with embryogenesis impaired primarily during the heart and torpedo stages, which are critical phases for plastid differentiation into chloroplasts. Using transgenic plants expressing EGFP-fused proteins, we confirmed that ACHT and TrxL2 are localized in plastids during embryogenesis. Additionally, seed development in the acht/trxl2 mutant was further impaired under extended darkness and could not be recovered through complementation with variants of ACHT or TrxL2 lacking the redox-active Cys residue (replaced by Ser). These findings indicate that the protein-oxidation functions of ACHT and TrxL2 are important for plastid differentiation into chloroplasts, embryogenesis, and seed development.

The oviposition of cotton bollworms stimulates the defense against its eggs and larvae in tomato plants

BACKGROUND

Herbivorous insects sustain their populations by oviposition. To reduce the damage caused by herbivores, the host plant triggers a defensive response upon detection of egg deposition. However, the specific impact of the egg deposition time of the cotton bollworm Helicoverpa armigera (Lepidoptera: Noctuidae), on the tomato plant defense remains obscure.

RESULTS

This study investigated the effects of tomato plant defenses on cotton bollworm eggs and larvae at different time intervals following egg deposition. The study revealed that tomato plant defense triggered by egg deposition did not directly affect the hatchability of the eggs. Nevertheless, it attracted Trichogramma chilonis 48 h after the egg deposition. Gas chromatography-mass spectrometry analysis of the oviposition-induced plant volatiles (OIPVs) revealed a considerable increase in the amount of α-pinene released by tomato plants 48 h after egg deposition. The olfactory results from Y-tube experiments showed that α-pinene exhibited a substantial attraction towards T. chilonis. In addition, it was found that the defense response induced by egg deposition for 24 and 48 h significantly inhibited the growth and development of the larvae. Metabolomics analysis revealed that the egg deposition of cotton bollworm altered the metabolite composition and caused significant modifications in the metabolic pathways of tomato plants.

CONCLUSION

These findings provide novel insights into pest management by using egg-induced plant defenses to reduce egg hatching, and impede larval growth and development in herbivorous insects. © 2024 Society of Chemical Industry.

Metabolic reprogramming in hepatocellular carcinoma: mechanisms and therapeutic implications

Hepatocellular carcinoma features extensive metabolic reprogramming. This includes alterations in major biochemical pathways such as glycolysis, the pentose phosphate pathway, amino acid metabolism and fatty acid metabolism. Moreover, there is a complex interplay among these altered pathways, particularly involving acetyl-CoA (coenzyme-A) metabolism and redox homeostasis, which in turn influences reprogramming of other metabolic pathways. Understanding these metabolic changes and their interactions with cellular signaling pathways offers potential strategies for the targeted treatment of hepatocellular carcinoma and improved patient outcomes. This review explores the specific metabolic alterations observed in hepatocellular carcinoma and highlights their roles in the progression of the disease.

Dynamic photosynthetic labeling and carbon-positional mass spectrometry monitor in vivo RUBISCO carbon assimilation rates

RIBULOSE-1,5-BISPHOSPHATE CARBOXYLASE/OXYGENASE (RUBISCO) is the most abundant enzyme and CO2 bio-sequestration system on Earth. Its in vivo activity is usually determined by 14CO2 incorporation into 3-phosphoglycerate (3PGA). However, the radiometric analysis of 3PGA does not distinguish carbon positions. Hence, RUBISCO activity that fixes carbon into the 1-C position of 3PGA and Calvin-Benson-Bassham (CBB) cycle activities that redistribute carbon into its 2-C and 3-C positions are not resolved. This study aims to develop technology that differentiates between these activities. In source fragmentation of gas chromatography-mass spectrometry (GC-MS) enables paired isotopologue distribution analyses of fragmented substructures and the complete metabolite structure. GC-MS measurements after dynamic photosynthetic 13CO2 labeling allowed quantification of the 13C fractional enrichment (E13C) and molar carbon assimilation rates (A13C) at carbon position 1-C of 3PGA by combining E13C from carbon positions 2,3-C2 and 1,2,3-C3 with quantification of 3PGA concentrations. We validated the procedure using two GC-time of flight-MS instruments, operated at nominal or high mass resolution, and tested the expected 3PGA positional labeling by in vivo glycolysis of positional labeled glucose isotopomers. Mutant analysis of the highly divergent GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASEs (GAPDH1 and 2) from Synechocystis sp. PCC 6803 revealed full inactivation of the CBB cycle with maintained RUBISCO activity in Δgapdh2 and a CBB cycle modulating role of GAPDH1 under fluctuating CO2 supply. RUBISCO activity in the CBB-deficient Δgapdh2 can re-assimilate CO2 released by catabolic pathways. We suggest that RUBISCO activity in Synechocystis can scavenge carbon lost through the pentose phosphate pathway or other cellular decarboxylation reactions.

Analysis of the spatial distribution of metabolites in Aloe vera leaves by mass spectrometry imaging and UHPLC-UHRMS

This study presents an investigation of the chemical composition of Aloe vera leaf tissue with a focus on the spatial distribution of compounds. The composition was studied using two mass spectrometry imaging techniques: silver-109 nanoparticles assisted laser desorption/ionization mass spectrometry imaging (109AgNPs-LDI-MSI) and laser ablation-remote atmospheric pressure photoionization/chemical ionization mass spectrometry imaging (LARAPPI/CI-MSI) and the identification was aided by ultra-high-performance liquid chromatography and ultra-high-resolution mass spectrometry (UHPLC-UHRMS) analysis. The results showed an abundance of phenolic compounds with antioxidant, antimicrobial, and anti-inflammatory properties, making it a beneficial food additive and food packaging material. Analysis of the results of mass spectrometry imaging provided information about the potential changes in metabolic pathway expression in different regions of the leaf.

Bacillus amyloliquefaciens modulate autophagy pathways to control Rhizoctonia solani infection in rice

The necrotrophic fungus Rhizoctonia solani significantly threatens rice harvests and agricultural productivity by causing sheath blight disease. This study investigates the potential of the plant growth-promoting rhizobacteria Bacillus amyloliquefaciens (SN13) as a biocontrol agent in the sensitive rice variety Swarna against R. solani infection. Disease incidence analysis reveals untreated rice plants suffer from R. solani infection, while SN13 treatment effectively suppresses fungal growth. In detached leaf assays, SN13 mitigates R. solani-induced damage, and physio-biochemical analyses indicate improved growth in SN13-treated rice plants. Notably, treatment with chloroquine, an autophagy inhibitor, increases disease incidence, whereas SN13 treatment enhances the formation of autophagosomes stained with Mono Dansyl Cadaverine (MDC) dye, as observed through confocal microscopy, suggesting the involvement of autophagy in plant defense against R. solani. Gene expression analysis reveals alterations in ATG and defence-related genes (BZ1, 5H5, and 8A1), affirming that SN13 activates autophagy and bolsters plant resilience. Metabolite analysis using GC-MS indicates the accumulation of defence signalling molecules such as gluconic acid, arabitol, glucopyranoside, ribose, xylopyranose, and arabinofuranoside. Overall, this study demonstrates the role of SN13 in inducing the autophagy response and modulating crucial defense pathways to control R. solani infection in rice var Swarna.

A Cytosolic Phosphoglucose Isomerase, OsPGI1c, Enhances Plant Growth and Herbivore Resistance in Rice

Glucose-6-phosphate isomerase (PGI), a key enzyme that catalyzes the reversible conversion of glucose-6-phosphate and fructose-6-phosphate, plays an important role in plant growth, development, and responses to abiotic stresses and pathogen infections. However, whether and how PGI modulates herbivore-induced plant defenses remain largely unknown. The Brown planthopper (BPH, Nilaparvata lugens) is a devastating insect pest of rice, causing significant damage to rice plants through feeding, oviposition, and disease transmission, resulting in great yield losses. Here, we isolated a rice cytosolic PGI gene, OsPGI1c, which is ubiquitously expressed in rice plants; the highest transcript levels are found in leaves, outer leaf sheaths, and seeds. The expression of OsPGI1c was induced by infestation by gravid females of the BPH, mechanical wounding, and treatment with jasmonic acid (JA). Overexpressing OsPGI1c in rice (oePGI) enhanced both the masses of plant shoots and roots and basal levels of trehalose; however, when infested by gravid BPH females for 2 days, trehalose levels were significantly lower in oePGI plants than in wild-type (WT) plants. Additionally, the overexpression of OsPGI1c increased the BPH-induced levels of JA, jasmonoyl-L-isoleucine, and abscisic acid, but decreased the levels of ethylene and H2O2. Bioassays revealed that gravid BPH females preferred WT plants over oePGI plants for laying eggs; moreover, BPH eggs exhibited lower hatching rates and required longer developmental durations on oePGI plants than WT plants. These results indicate that OsPGI1c positively modulates both rice growth and BPH resistance.

Lack of Arabidopsis chloroplastic glucose-6-phosphate dehydrogenase 1 (G6PD1) affects lipid synthesis during cold stress response

Cold stress represents one of the major constraints for agricultural systems and crops productivity, inducing a wide range of negative effects. Particularly, long-term cold stress affects lipid metabolism, modifying the lipids/proteins ratio, the levels of phospholipids and glycolipids, and increasing lipids' unsaturation in bio-membranes. Glucose-6-phosphate dehydrogenase (G6PDH) reported prominent roles as NADPH suppliers in response to oxidative perturbations. Cytosolic G6PDH was suggested as the main isoform involved in cold stress response, while a down-regulation of the chloroplastic P1-G6PDH was observed. We thus investigated an Arabidopsis mutant defective for the P1-G6PDH (KO-P1) using integrated approaches to verify a possible role of this isoform in low temperature tolerance. KO-P1 genotype showed an improved tolerance to cold stress, highlighting a better photosynthetic efficiency, a reduction in stress markers content and a different regulation of genes involved in stress response. Intriguingly, the lack of P1-G6PDH induced modification in the levels of the main fatty acid and lipid species affecting the morphology of chloroplasts and mitochondria, which was restored under cold. Globally, these results indicate a priming effect induced by the absence of P1-G6PDH able to improve the tolerance to abiotic stress. Our results suggest novel and specific abilities of P1-G6PDH, highlighting its central role in different aspects of plant physiology and metabolism.

Bioinformatics analysis of the Microsporidia sp. MB genome: a malaria transmission-blocking symbiont of the Anopheles arabiensis mosquito

BACKGROUND

The use of microsporidia as a disease-transmission-blocking tool has garnered significant attention. Microsporidia sp. MB, known for its ability to block malaria development in mosquitoes, is an optimal candidate for supplementing malaria vector control methods. This symbiont, found in Anopheles mosquitoes, can be transmitted both vertically and horizontally with minimal effects on its mosquito host. Its genome, recently sequenced from An. arabiensis, comprises a compact 5.9 Mbp.

RESULTS

Here, we analyze the Microsporidia sp. MB genome, highlighting its major genomic features, gene content, and protein function. The genome contains 2247 genes, predominantly encoding enzymes. Unlike other members of the Enterocytozoonida group, Microsporidia sp. MB has retained most of the genes in the glycolytic pathway. Genes involved in RNA interference (RNAi) were also identified, suggesting a mechanism for host immune suppression. Importantly, meiosis-related genes (MRG) were detected, indicating potential for sexual reproduction in this organism. Comparative analyses revealed similarities with its closest relative, Vittaforma corneae, despite key differences in host interactions.

CONCLUSION

This study provides an in-depth analysis of the newly sequenced Microsporidia sp. MB genome, uncovering its unique adaptations for intracellular parasitism, including retention of essential metabolic pathways and RNAi machinery. The identification of MRGs suggests the possibility of sexual reproduction, offering insights into the symbiont's evolutionary strategies. Establishing a reference genome for Microsporidia sp. MB sets the foundation for future studies on its role in malaria transmission dynamics and host-parasite interactions.

Evolution of plant metabolism: the state-of-the-art

Immense chemical diversity is one of the hallmark features of plants. This chemo-diversity is mainly underpinned by a highly complex and biodiverse biochemical machinery. Plant metabolic enzymes originated and were inherited from their eukaryotic and prokaryotic ancestors and further diversified by the unprecedentedly high rates of gene duplication and functionalization experienced in land plants. Unlike prokaryotic microbes, which display frequent horizontal gene transfer events and multiple inputs of energy and organic carbon, land plants predominantly rely on organic carbon generated from CO2 and have experienced relatively few gene transfers during their recent evolutionary history. As such, plant metabolic networks have evolved in a stepwise manner using existing networks as a starting point and under various evolutionary constraints. That said, until recently, the evolution of only a handful of metabolic traits had been extensively investigated and as such, the evolution of metabolism has received a fraction of the attention of, the evolution of development, for example. Advances in metabolomics and next-generation sequencing have, however, recently led to a deeper understanding of how a wide range of plant primary and specialized (secondary) metabolic pathways have evolved both as a consequence of natural selection and of domestication and crop improvement processes. This article is part of the theme issue 'The evolution of plant metabolism'.

The effect of nutritional and oxidative stress on the metabolome of Trypanosoma cruzi

Trypanosoma cruzi, a flagellated protozoan, is the causative agent of Chagas disease. The parasite has developed various mechanisms to get through its intricate life cycle and adapt to different evolutionary phases. T. cruzi proliferates in the insect vector's digestive tract as an epimastigote form, encountering fluctuating nutrient availability and oxidative stress caused by the digestion of red blood cells from the mammalian host blood meal. To unravel how the parasite's metabolism adapts to these changing conditions, we conducted an analysis of the chemical species present in epimastigote forms. This involved comparing cultured parasites with those subjected to nutritional deficiency or oxidative stress using untargeted metabolomics. We looked at 21 samples: seven biological copies of parasites that were actively growing, seven samples that were put in a medium without nutrients for 3 h, and seven samples that were treated with glucose oxidase for 30 min to make H2O2 continuously. Importantly, in all conditions, parasite viability was maintained when the samples were collected. Upon nutrient removal, we observed a substantial decrease in amino acids and carbohydrate metabolites, accompanied by the accumulation of fatty acids and steroids, with the predominance of inositol and sphingolipid metabolism, along with a simultaneous decrease in the levels of H2O2. In the presence of H2O2, a significant rise in components of the pentose pathway and specific amino acids such as methionine and serine occurred, along with pathways related to an increase in antioxidant species metabolism such as ribulose 5-phosphate and glyceric acid. Conversely, fatty acid and steroid levels decrease. We found no common increase in metabolites or lipids. In contrast, eight species (succinic acid, glutamic acid, valine, 2-hydroxyisocaproic acid, alanine, indolelactic acid, proline, and lanosterol) were consumed under both stresses. These findings underscore the rapid and distinct enrichment responses in amino acids, lipids, and carbohydrates required to cope with each different environmental condition. We concluded that T. cruzi presents a flexible metabolism that rapidly adapts to variable changes in the environment.

6-Phosphogluconate dehydrogenase 2 bridges the OPP and shikimate pathways to enhance aromatic amino acid production in plants

The oxidative pentose phosphate (OPP) pathway provides metabolic intermediates for the shikimate pathway and directs carbon flow to the biosynthesis of aromatic amino acids (AAAs), which serve as basic protein building blocks and precursors of numerous metabolites essential for plant growth. However, genetic evidence linking the two pathways is largely unclear. In this study, we identified 6-phosphogluconate dehydrogenase 2 (PGD2), the rate-limiting enzyme of the cytosolic OPP pathway, through suppressor screening of arogenate dehydrogenase 2 (adh2) in Arabidopsis. Our data indicated that a single amino acid substitution at position 63 (glutamic acid to lysine) of PGD2 enhanced its enzyme activity by facilitating the dissociation of products from the active site of PGD2, thus increasing the accumulation of AAAs and partially restoring the defective phenotype of adh2. Phylogenetic analysis indicated that the point mutation occurred in a well-conserved amino acid residue. Plants with different amino acids at this conserved site of PGDs confer diverse catalytic activities, thus exhibiting distinct AAAs producing capability. These findings uncover the genetic link between the OPP pathway and AAAs biosynthesis through PGD2. The gain-of-function point mutation of PGD2 identified here could be considered as a potential engineering target to alter the metabolic flux for the production of AAAs and downstream compounds.

Accumulation of dually targeted StGPT1 in chloroplasts mediated by StRFP1, an E3 ubiquitin ligase, enhances plant immunity

Chloroplasts play a crucial role in essential processes, such as photosynthesis and the synthesis of primary and diverse secondary metabolites. Recent studies have also highlighted their significance linked to phytohormone production in plant immunity, especially SA and JA. Ubiquitination, a key posttranslational modification, usually leads to target protein degradation, which acts as a signal for remodeling the proteome via the induction of protein endocytosis or targeting to other membrane associated systems. Previously, the potato E3 ligase StRFP1 was shown to enhance resistance against Phytophthora infestans, but its mechanism remained unclear. Here, we demonstrate that StRFP1 interacted with the dually localized plastid glucose 6-phosphate transporter StGPT1 on the endoplasmic reticulum (ER). Transiently expressed StGPT1-GFP located on the chloroplast and ER in plant cells. Overexpression of StGPT1 enhances late blight resistance in potato and Nicotiana benthamiana, activates immune responses, including ROS bursts and up-regulation of PTI marker genes. The resistance function of StGPT1 seems to be related to its dual localization. Remarkably, StRFP1 ubiquitinates StGPT1 at the ER, possibly due to its merely transient function in peroxisomes, leading to apparent accumulation in chloroplasts. Our findings point to a novel mechanism by which a plant E3 ligase contributes to immunity via interacting with dually targeted GPT1 at the ER of plant cells.

Metabolic characteristics of ischaemic preconditioning induced performance improvement in Taekwondo athletes using LC‒MS/MS-based plasma metabolomics

In recent years, ischemic preconditioning (IPC) has garnered significant attention in sports research. While IPC has demonstrated positive effects in high-intensity sports such as judo and swimming, its potential benefits for enhancing the performance of Taekwondo athletes have not been extensively studied. This study aimed to investigate the effects of IPC on taekwondo performance and to observe the metabolic characteristics associated with enhancing sports performance via LC‒MS/MS-based plasma metabolomics. Seventeen participants underwent the repeated frequency speed of kick test (FSKT) after IPC, along with pre- and post-exercise plasma metabolite analysis. Differential abundance metabolite analysis, enriched pathway analysis, and weighted gene coexpression network analysis (WGNCA) were employed to delve into metabolic characteristics. The findings highlighted a significant enhancement in FSKT performance in the experimental group. Metabolomic analysis revealed 109 differentially abundant metabolites, including Dl-lactate, hypoxanthine, acetylcarnitine, and acetylsalicylic acid. Enriched pathway analysis revealed pathways such as pentose and glucuronic acid interconversion, ascorbic acid and aldonic acid metabolism, the pentose phosphate pathway (PPP), and the Warburg effect. In conclusion, IPC can significantly increase the specific athletic abilities of Taekwondo athletes, with enhancements linked to anaerobic metabolism, PPP utilization, the Warburg effect for energy production, redox system stability, reduced muscle fatigue, and pain alleviation.

Exploration of Nutraceutical Potentials of Isorhapontigenin, Oxyresveratrol and Pterostilbene: A Metabolomic Approach

Resveratrol (trans-3,5,4'-trihydroxystilbene, RES) is one of the most well-known natural products with numerous health benefits. To explore the nutraceutical potentials of some dietary RES derivatives including isorhapontigenin (trans-3,5,4'-trihydroxy-3'-methoxystilbene, ISO), oxyresveratrol (trans-3,5,2',4'-tetrahydroxystilbene, OXY) and pterostilbene (trans-3,5-dimethoxy-4'-hydroxystilbene, PTS), their impacts on metabolism and health were assessed in Sprague Dawley rats after a two-week daily oral administration at the dose of 100 µmol/kg/day. Non-targeted metabolomic analyses were carried out with the liver, heart, brain and plasma samples using gas chromatography-tandem mass spectrometry (GC-MS/MS). Notable in vivo health benefits were observed, as the rats received ISO, PTS or RES showed less body weight gain; the rats received OXY or RES displayed healthier fasting blood glucose levels; while all of the tested stilbenes exhibited cholesterol-lowering effects. Additionally, many important metabolic pathways such as glycolysis, pentose phosphate pathway, tricarboxylic acid cycle and fatty acid oxidation were found to be modulated by the tested stilbenes. Besides the reaffirmation of the well-known beneficial effects of RES in diabetes, obesity, cardiovascular disease and Alzheimer's disease, the metabolomic analyses also suggest the anti-diabetic, cardio-, hepato- and neuro-protective activities of ISO; the anti-diabetic, cardio-, hepato- and neuro-protective effects of OXY; and the anti-aging, anti-inflammatory, cardio-, hepato- and neuro-protective potential of PTS. Interestingly, although these stilbenes share a similar structure, their biological activities appear to be distinct. In conclusion, similarly to RES, ISO, OXY and PTS have emerged as promising candidates for further nutraceutical development.

Synthesis of Novel Propionamide-Methylpyrazole Carboxylates as Herbicidal Candidates

Transketolase (TKL; EC 2.2.1.1) is a highly promising potential target for herbicidal applications. To identify novel TKL inhibitors, we designed and synthesized a series of 3-oxopropionamide-1-methylpyrazole carboxylate analogues and assessed their herbicidal activities. Ethyl 3-((1-((2,4-dichlorophenyl)amino)-1-oxopropan-2-yl)oxy)-1-methyl-1H-pyrazole-5-carboxylate (D15) and ethyl 1-methyl-3-((1-oxo-1-((thiophen-2-ylmethyl)amino)propan-2-yl)oxy)-1H-pyrazole-5-carboxylate (D20) exhibited superior growth inhibition activities against both the root and stem of Amaranthus retroflexus (A. retroflexus) compared to nicosulfuron and mesotrione. Additionally, D15 achieved an inhibition rate of more than 90% against the roots and stems of Digitaria sanguinalis (D. sanguinalis), outperforming the four control agents at a concentration of 200 mg/L using the small cup method. In the pre-emergence herbicidal activity test, D15 effectively inhibited D. sanguinalis by more than 90% at 150 g ai/ha, surpassing the efficacy of the control, mesotrione. Conversely, in the postemergence herbicidal activity test, D20 exhibited efficient inhibition of A. retroflexus by more than 90% at 150 g ai/ha, outperforming the control agents nicosulfuron, mesotrione, and metamifop. The results of the TKL enzyme activity test showed that the IC50 values of compounds D15 and D20 were 0.384 and 0.655 mg/L, respectively, which were close to those of the control agents. Furthermore, molecular docking and molecular dynamics simulation studies revealed that D15 and D20 interacted favorably with the TKL of Setaria viridis. Such findings highlight the promising potential of D15 and D20 as lead TKL inhibitors for the optimization of new herbicides.

De novo biosynthesis of β-Arbutin in Komagataella phaffii based on metabolic engineering strategies

BACKGROUND

β-Arbutin, found in the leaves of bearberry, stands out as one of the globally acknowledged eco-friendly whitening additives in recent years. However, the natural abundance of β-Arbutin is low, and the cost-effectiveness of using chemical synthesis or plant extraction methods is low, which cannot meet the requirements. While modifying the β-Arbutin synthesis pathway of existing strains is a viable option, it is hindered by the limited synthesis capacity of these strains, which hinders further development and application.

RESULTS

In this study, we established a biosynthetic pathway in Komagataella phaffii for β-Arbutin production with a titer of 1.58 g/L. Through diverse metabolic strategies, including fusion protein construction, enhancing shikimate pathway flux, and augmenting precursor supplies (PEP, E4P, and UDPG), we significantly increased β-Arbutin titer to 4.32 g/L. Further optimization of methanol concentration in shake flasks led to a titer of 6.32 g/L titer after 120 h of fermentation, representing a fourfold increase over the initial titer. In fed-batch fermentation, strain UA3-10 set a record with the highest production to date, reaching 128.6 g/L in a 5 L fermenter.

CONCLUSIONS

This is the highest yield in the fermentation tank level of using microbial cell factories for de novo synthesis of β-Arbutin. Applying combinatorial engineering strategies has significantly improved the β-Arbutin yield in K. phaffii and is a promising approach for synthesizing functional products using a microbial cell factory. This study not only advances low-cost fermentation-based production of β-Arbutin but also establishes K. phaffii as a promising chassis cell for synthesizing other aromatic amino acid metabolites.

Metabolic perturbation and oxidative damage induced by tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and tris(2-ethylhexyl) phosphate (TEHP) on Escherichia coli through integrative analyses of metabolome

Organophosphate esters (OPEs) are one of the emerging environmental threats, causing the hazard to ecosystem safety and human health. Yet, the toxic effects and metabolic response mechanism after Escherichia coli (E.coli) exposed to TDCIPP and TEHP is inconclusive. Herein, the levels of SOD and CAT were elevated in a concentration-dependent manner, accompanied with the increase of MDA contents, signifying the activation of antioxidant response and occurrence of lipid peroxidation. Oxidative damage mediated by excessive accumulation of ROS decreased membrane potential and inhibited membrane protein synthesis, causing membrane protein dysfunction. Integrative analyses of GC-MS and LC-MS based metabolomics evinced that significant perturbation to the carbohydrate metabolism, nucleotide metabolism, lipids metabolism, amino acid metabolism, organic acids metabolism were induced following exposure to TDCIPP and TEHP in E.coli, resulting in metabolic reprogramming. Additionally, metabolites including PE(16:1(5Z)/15:0), PA(17:0/15:1(9Z)), PC(20:2(11Z,14Z)/12:0), LysoPC(18:3(6Z,9Z,12Z)/0:0) were significantly upregulated, manifesting that cell membrane protective molecule was afforded by these differential metabolites to improve permeability and fluidity. Overall, current findings generate new insights into the molecular toxicity mechanism by which E.coli respond to TDCIPP and TEHP stress and supply valuable information for potential ecological risks of OPEs on aquatic ecosystems.

Dehydroepiandrosterone-α-2-Deoxyglucoside Exhibits Enhanced Anticancer Effects in MCF-7 Breast Cancer Cells and Inhibits Glucose-6-Phosphate Dehydrogenase Activity

In the pentose phosphate pathway, dehydroepiandrosterone (DHEA) uncompetitively inhibits glucose-6-phosphate dehydrogenase (G6PD), reducing NADPH production and increasing oxidative stress, which can influence the onset and/or progression of several diseases, including cancer. 2-Deoxy-D-glucose (2-DG), a glucose mimetic, competes with glucose for cellular uptake, inhibiting glycolysis and competing with glucose-6-phosphate (G-6-P) for G6PD activity. In this study, we report that DHEA-α-2-DG (5), an α-covalent conjugate of DHEA and 2-DG, exhibits better anticancer activity than DHEA, 2-DG, DHEA +2-DG, and polydatin in MCF-7 cells, and reduces NADPH/NADP+ ratio in cellular assays. In vitro enzyme kinetics and molecular docking studies showed that 5 uncompetitively inhibits human G6PD activity and binds to the structural NADP+ site but not to the catalytic NADP+ site. Further combining 5 with the FDA-approved drug tamoxifen enhanced its cytotoxicity against MCF-7 cells, suggesting that it could serve as a candidate for combination of drug strategies.

Sucrose as an electron source for cofactor regeneration in recombinant Escherichia coli expressing invertase and a Baeyer Villiger monooxygenase

BACKGROUND

The large-scale biocatalytic application of oxidoreductases requires systems for a cost-effective and efficient regeneration of redox cofactors. These represent the major bottleneck for industrial bioproduction and an important cost factor. In this work, co-expression of the genes of invertase and a Baeyer-Villiger monooxygenase from Burkholderia xenovorans to E. coli W ΔcscR and E. coli BL21 (DE3) enabled efficient biotransformation of cyclohexanone to the polymer precursor, ε-caprolactone using sucrose as electron source for regeneration of redox cofactors, at rates comparable to glucose. E. coli W ΔcscR has a native csc regulon enabling sucrose utilization and is deregulated via deletion of the repressor gene (cscR), thus enabling sucrose uptake even at concentrations below 6 mM (2 g L-1). On the other hand, E. coli BL21 (DE3), which is widely used as an expression host does not contain a csc regulon.

RESULTS

Herein, we show a proof of concept where the co-expression of invertase for both E. coli hosts was sufficient for efficient sucrose utilization to sustain cofactor regeneration in the Baeyer-Villiger oxidation of cyclohexanone. Using E. coli W ΔcscR, a specific activity of 37 U gDCW-1 was obtained, demonstrating the suitability of the strain for recombinant gene co-expression and subsequent whole-cell biotransformation. In addition, the same co-expression cassette was transferred and investigated with E. coli BL21 (DE3), which showed a specific activity of 17 U gDCW- 1. Finally, biotransformation using photosynthetically-derived sucrose from Synechocystis S02 with E. coli W ΔcscR expressing BVMO showed complete conversion of cyclohexanone after 3 h, especially with the strain expressing the invertase gene in the periplasm.

CONCLUSIONS

Results show that sucrose can be an alternative electron source to drive whole-cell biotransformations in recombinant E. coli strains opening novel strategies for sustainable chemical production.

N-glycosylation of SnRK2s affects NADPH maintenance in peroxisomes during prolonged ABA signalling

Unfavourable conditions, such as prolonged drought and high salinity, pose a threat to the survival and agricultural yield of plants. The phytohormone ABA plays a key role in the regulation of plant stress adaptation and is often maintained at high levels for extended periods. While much is known about ABA signal perception and activation in the early signalling stage, the molecular mechanism underlying desensitization of ABA signalling remains largely unknown. Here we demonstrate that in the endoplasmic reticulum (ER)-Golgi network, the key regulators of ABA signalling, SnRK2.2/2.3, undergo N-glycosylation, which promotes their redistribution from the nucleus to the peroxisomes in Arabidopsis roots and influences the transcriptional response in the nucleus during prolonged ABA signalling. On the peroxisomal membrane, SnRK2s can interact with glucose-6-phosphate (G6P)/phosphate translocator 1 (GPT1) to maintain NADPH homeostasis through increased activity of the peroxisomal oxidative pentose phosphate pathway (OPPP). The resulting maintenance of NADPH is essential for the modulation of hydrogen peroxide (H2O2) accumulation, thereby relieving ABA-induced root growth inhibition. The subcellular dynamics of SnRK2s, mediated by N-glycosylation suggest that ABA responses transition from transcriptional regulation in the nucleus to metabolic processes in the peroxisomes, aiding plants in adapting to long-term environmental stress.

Multi-Omics Analyses of Lettuce (Lactuca sativa) Reveals Primary Metabolism Reorganization Supporting Distinct Features of Secondary Metabolism Induced by Supplementing UV-A Radiation

UV can serve as an effective light spectrum for regulating plant secondary metabolites, while relevant studies on UV-A are much less extensive than those on UV-B. A comprehensive understanding of the selective effects of UV-A on different secondary metabolites and the specific features of primary metabolism that drive these effects is still lacking. To address this knowledge gap, we conducted a study to analyze the dynamic changes in the metabolome and transcriptome of lettuce leaves irradiated with red plus UV-A light (monochromatic red light as control). Generally, UV-A promoted the synthesis of most phenylpropanoids and terpenoids originating from the shikimate and methylerythritol phosphate (MEP) pathway in plastids but sacrificed the synthesis of terpenoids derived from the mevalonate (MVA) pathway, particularly sesquiterpenes. Increased precursors supply for the shikimate and MEP pathway under UV-A was directly supported by the activation of the Calvin-Benson cycle and phosphoenolpyruvate transport. Whereas, along with phosphoenolpyruvate transport, the TCA cycle was restrained, causing deprivation of the MVA pathway precursor. In addition, UV-A also activated the plastidic oxidative branch of the pentose phosphate pathway, photorespiration, and malate shuttle, to ensure a sufficient supply of nitrogen, circulation homeostasis of the Calvin-Benson cycle, and energy balance, thus indirectly supporting UV-A-induced specific secondary metabolic output. This study provides a comprehensive framework for understanding the flexible primary-secondary metabolism interactions that are able to produce specific metabolites favorable for adaptation to environmental stimuli.

B Vitamins: An Update on Their Importance for Plant Homeostasis

B vitamins are a source of coenzymes for a vast array of enzyme reactions, particularly those of metabolism. As metabolism is the basis of decisions that drive maintenance, growth, and development, B vitamin-derived coenzymes are key components that facilitate these processes. For over a century, we have known about these essential compounds and have elucidated their pathways of biosynthesis, repair, salvage, and degradation in numerous organisms. Only now are we beginning to understand their importance for regulatory processes, which are becoming an important topic in plants. Here, I highlight and discuss emerging evidence on how B vitamins are integrated into vital processes, from energy generation and nutrition to gene expression, and thereby contribute to the coordination of growth and developmental programs, particularly those that concern maintenance of a stable state, which is the foundational tenet of plant homeostasis.

From ubiquity to specificity: The diverse functions of bacterial thioredoxin systems

The thioredoxin (Trx) system, found universally, is responsible for the regeneration of reversibly oxidized protein thiols in living cells. This system is made up of a Trx and a Trx reductase, and it plays a central role in maintaining thiol-based redox homeostasis by reducing oxidized protein thiols, such as disulfide bonds in proteins. Some Trxs also possess a chaperone function that is independent of thiol-disulfide exchange, in addition to their thiol-disulfide reductase activity. These two activities of the Trx system are involved in numerous physiological processes in bacteria. This review describes the diverse physiological roles of the Trx system that have emerged throughout bacterial evolution. The Trx system is essential for responding to oxidative and nitrosative stress. Beyond this primary function, the Trx system also participates in redox regulation and signal transduction, and in controlling metabolism, motility, biofilm formation, and virulence. This range of functions has evolved alongside the diversity of bacterial lifestyles and their specific constraints. This evolution can be characterized by the multiplication of the systems and by the specialization of cofactors or targets to adapt to the constraints of atypical lifestyles, such as photosynthesis, insect endosymbiosis, or spore-forming bacteria.

Evidence for dual targeting control of Arabidopsis 6-phosphogluconate dehydrogenase isoforms by N-terminal phosphorylation

The oxidative pentose-phosphate pathway (OPPP) retrieves NADPH from glucose-6-phosphate, which is important in chloroplasts at night and in plastids of heterotrophic tissues. We previously studied how OPPP enzymes may transiently locate to peroxisomes, but how this is achieved for the third enzyme remained unclear. By extending our genetic approach, we demonstrated that Arabidopsis isoform 6-phosphogluconate dehydrogenase 2 (PGD2) is indispensable in peroxisomes during fertilization, and investigated why all PGD-reporter fusions show a mostly cytosolic pattern. A previously published interaction of a plant PGD with thioredoxin m was confirmed using Trxm2 for yeast two-hybrid (Y2H) and bimolecular fluorescent complementation (BiFC) assays, and medial reporter fusions (with both ends accessible) proved to be beneficial for studying peroxisomal targeting of PGD2. Of special importance were phosphomimetic changes at Thr6, resulting in a clear targeting switch to peroxisomes, while a similar change at position Ser7 in PGD1 conferred plastid import. Apparently, efficient subcellular localization can be achieved by activating an unknown kinase, either early after or during translation. N-terminal phosphorylation of PGD2 interfered with dimerization in the cytosol, thus allowing accessibility of the C-terminal peroxisomal targeting signal (PTS1). Notably, we identified amino acid positions that are conserved among plant PGD homologues, with PTS1 motifs first appearing in ferns, suggesting a functional link to fertilization during the evolution of seed plants.

Integrative physiology and transcriptome reveal salt-tolerance differences between two licorice species: Ion transport, Casparian strip formation and flavonoids biosynthesis

BACKGROUND

Glycyrrhiza inflata Bat. and Glycyrrhiza uralensis Fisch. are both original plants of 'Gan Cao' in the Chinese Pharmacopoeia, and G. uralensis is currently the mainstream variety of licorice and has a long history of use in traditional Chinese medicine. Both of these species have shown some degree of tolerance to salinity, G. inflata exhibits higher salt tolerance than G. uralensis and can grow on saline meadow soils and crusty saline soils. However, the regulatory mechanism responsible for the differences in salt tolerance between different licorice species is unclear. Due to land area-related limitations, the excavation and cultivation of licorice varieties in saline-alkaline areas that both exhibit tolerance to salt and contain highly efficient active substances are needed. The systematic identification of the key genes and pathways associated with the differences in salt tolerance between these two licorice species will be beneficial for cultivating high-quality salt-tolerant licorice G. uralensis plant varieties and for the long-term development of the licorice industry. In this research, the differences in growth response indicators, ion accumulation, and transcription expression between the two licorice species were analyzed.

RESULTS

This research included a comprehensive comparison of growth response indicators, including biomass, malondialdehyde (MDA) levels, and total flavonoids content, between two distinct licorice species and an analysis of their ion content and transcriptome expression. In contrast to the result found for G. uralensis, the salt treatment of G. inflata ensured the stable accumulation of biomass and total flavonoids at 0.5 d, 15 d, and 30 d and the restriction of Na+ to the roots while allowing for more K+ and Ca2+ accumulation. Notably, despite the increase in the Na+ concentration in the roots, the MDA concentration remained low. Transcriptome analysis revealed that the regulatory effects of growth and ion transport on the two licorice species were strongly correlated with the following pathways and relevant DEGs: the TCA cycle, the pentose phosphate pathway, and the photosynthetic carbon fixation pathway involved in carbon metabolism; Casparian strip formation (lignin oxidation and translocation, suberin formation) in response to Na+; K+ and Ca2+ translocation, organic solute synthesis (arginine, polyamines, GABA) in response to osmotic stresses; and the biosynthesis of the nonenzymatic antioxidants carotenoids and flavonoids in response to antioxidant stress. Furthermore, the differential expression of the DEGs related to ABA signaling in hormone transduction and the regulation of transcription factors such as the HSF and GRAS families may be associated with the remarkable salt tolerance of G. inflata.

CONCLUSION

Compared with G. uralensis, G. inflata exhibits greater salt tolerance, which is primarily attributable to factors related to carbon metabolism, endodermal barrier formation and development, K+ and Ca2+ transport, biosynthesis of carotenoids and flavonoids, and regulation of signal transduction pathways and salt-responsive transcription factors. The formation of the Casparian strip, especially the transport and oxidation of lignin precursors, is likely the primary reason for the markedly higher amount of Na+ in the roots of G. inflata than in those of G. uralensis. The tendency of G. inflata to maintain low MDA levels in its roots under such conditions is closely related to the biosynthesis of flavonoids and carotenoids and the maintenance of the osmotic balance in roots by the absorption of more K+ and Ca2+ to meet growth needs. These findings may provide new insights for developing and cultivating G. uralensis plant species selected for cultivation in saline environments or soils managed through agronomic practices that involve the use of water with a high salt content.

PGI1-mediated vascular oxidative pentose phosphate pathway modulates photosynthesis via long-distance cytokinin signaling

In Arabidopsis, the plastidial isoform of phosphoglucose isomerase, PGI1, mediates growth and photosynthesis, likely due to its involvement in the vascular production of cytokinins (CK). To examine this hypothesis, we characterized pgi1-2 knockout plants impaired in PGI1 and pgi1-2 plants specifically expressing PGI1 in root tips and vascular tissues. Moreover, to investigate whether the phenotype of pgi1-2 plants is due to impairments in the plastidial oxidative pentose phosphate pathway (OPPP) or the glycolytic pathway, we characterized pgl3-1 plants with reduced OPPP and pfk4pfk5 knockout plants impaired in plastidial glycolysis. Compared with wild-type (WT) leaves, pgi1-2 leaves exhibited weaker expression of photosynthesis- and 2-C-methyl-D-erythritol 4-P (MEP) pathway-related proteins, and stronger expression of oxidative stress protection-related enzymes. Consistently, pgi1-2 leaves accumulated lower levels of chlorophyll, and higher levels of tocopherols, flavonols and anthocyanins than the WT. Vascular- and root tip-specific PGI1 expression countered the reduced photosynthesis, low MEP pathway-derived CK content, dwarf phenotype and the metabolic characteristics of pgi1-2 plants, reverting them to WT-like levels. Moreover, pgl3-1, but not pfk4pfk5 plants phenocopied pgi1-2. Histochemical analyses of plants expressing GUS under the control of promoter regions of genes encoding plastidial OPPP enzymes exhibited strong GUS activity in root tips and vascular tissues. Overall, our findings show that root tip and vascular PGI1-mediated plastidial OPPP activity affects photosynthesis and growth through mechanisms involving long-distance modulation of the leaf proteome by MEP pathway-derived CKs.

Cadmium and copper-induced metabolic and proteomic changes in the root tip during early maize growth

In this study, the metabolic adjustments performed by maize (Zea mays L.) seminal roots exposed to 25 µM Cd2+ or 25 µM Cu2+ at pre-emergence are compared, focusing on the proteomic changes after metal exposure. Root width was increased, and root length was decreased after 72 h of metal treatment. Both metals induced H2O2 accumulation and lipid peroxidation in the root tip. These changes were accompanied by increases in lipoxygenase activity and 4-hydroxy-2-nonenal content. NMR spectroscopy revealed that the abundance of 38 water-soluble metabolites was significantly modified by Cd and Cu exposure; this set of metabolites comprised carboxylic acids, amino acids, carbohydrates, and unidentified phenolic compounds. Linoleic acid content significantly decreased in Cu-treated samples. The total amount of proteins detected in maize root apexes was 2,171. Gene ontology enrichment analysis of the differentially accumulated proteins was performed to detect pathways probably affected by metal additions. Both metals altered redox homeostasis, up-regulated oxylipins biosynthetic process, and shifted metabolism towards the oxidative pentose-phosphate in the root apexes. However, the methionine salvage pathway appears as a key metabolic module only under Cd stress. The integrative analysis carried out in this study suggests that most molecular features behind the reprogramming of maize root tips to cope with cadmium and copper toxicity are common, but some are not.

Transcriptomic and proteomic analyses of distinct Arabidopsis organs reveal high PSI-NDH complex accumulation in stems

In addition to leaves, the main site of photosynthetic reactions, active photosynthesis also takes place in stems, siliques and tree trunks. Although non-foliar photosynthesis has a marked effect on plant growth and yield, only limited information on the expression patterns of photosynthesis-related genes and the structure of photosynthetic machinery in different plant organs has been available. Here, we report the results of transcriptomic analysis of various organs of Arabidopsis thaliana and compare the gene expression profiles of young and mature leaves with a special focus on photosynthetic genes. Further, we analyzed the composition and organization of the photosynthetic electron transfer machinery in leaves, stems and green siliques at the protein level using BN-PAGE. RNA-Seq analysis revealed unique gene expression profiles in different plant organs and showed major differences in the expression of photosynthesis-related genes in young as compared to mature rosettes. Gel-based proteomic analysis of the thylakoid protein complex organization further showed that all studied plant organs contain the necessary components of the photosynthetic electron transfer chain. Intriguingly, stems accumulate high amounts of PSI-NDH complex, which has previously been implicated in cyclic electron transfer.

Physiological and transcriptomic analysis reveals the toxic and protective mechanisms of marine microalga Chlorella pyrenoidosa in response to TiO2 nanoparticles and UV-B radiation

Concerns have been raised regarding the adverse effects of nanoparticles (NPs) on marine organisms, as an increasing number of NPs inevitably enter the marine environment with the development of nanotechnology. Owing to the photocatalytic properties, TiO2 NPs' toxicity may be aggravated by enhanced UV-B resulting from stratospheric ozone depletion. However, the molecular mechanisms of phytoplankton in response to TiO2 NPs under UV-B remains poorly understood. In this study, we integrated whole transcriptome analysis with physiological data to provide understanding on the toxic and protective mechanisms of marine Chlorella pyrenoidosa in response to TiO2 NPs under UV-B. The results indicated that the changes in gene expression could be related to the growth inhibition and TiO2 NP internalization in C. pyrenoidosa, and several molecular mechanisms were identified as toxicity response to TiO2 NPs and UV-B. Differential expression of genes involved in glycerophospholipids metabolism indicated that cell membrane disruption allowed TiO2 NPs to enter the algal cell under UV-B exposure, although the up-regulation of genes involved in the general secretory dependent pathway and the ATP-binding cassette transporter family drove cellular secretion of extracellular polymeric substances, acting as a barrier that prevent TiO2 NP internalization. The absence of changes in gene expression related to the antioxidant system may be responsible for the severe oxidative stress observed in algal cells following exposure to TiO2 NPs under UV-B irradiation. Moreover, differential expression of genes involved in pathways such as photosynthesis and energy metabolism were up-regulated, including the light-harvesting, photosynthetic electron transport coupled to photophosphorylation, carbon fixation, glycolysis, pentose phosphate pathway, tricarboxylic acid cycle, and oxidative phosphorylation, indicating that more energy and metabolites were supplied to cope with the toxicity of TiO2 NPs and UV-B. The obtained results provide valuable information on the molecular mechanisms of response of marine phytoplankton exposed to TiO2 NPs and UV-B.

Integration of metabolomics and transcriptomics reveals the regulation mechanism of the phenylpropanoid biosynthesis pathway in insect resistance traits in Solanum habrochaites

Solanum habrochaites (SH), a wild species closely related to 'Ailsa Craig' (AC), is an important germplasm resource for modern tomato breeding. Trichomes, developed from epidermal cells, have a role in defense against insect attack, and their secretions are of non-negligible value. Here, we found that the glandular heads of type VI trichomes were clearly distinguishable between AC and SH under cryo-scanning electron microscopy, the difference indicating that SH could secrete more anti-insect metabolites than AC. Pest preference experiments showed that aphids and mites preferred to feed near AC compared with SH. Integration analysis of transcriptomics and metabolomics data revealed that the phenylpropanoid biosynthesis pathway was an important secondary metabolic pathway in plants, and SH secreted larger amounts of phenylpropanoids and flavonoids than AC by upregulating the expression of relevant genes in this pathway, and this may contribute to the greater resistance of SH to phytophagous insects. Notably, virus-induced silencing of Sl4CLL6 not only decreased the expression of genes downstream of the phenylpropanoid biosynthesis pathway (SlHCT, SlCAD, and SlCHI), but also reduced resistance to mites in tomato. These findings provided new genetic resources for the synthesis of phenylpropanoid compounds and anti-insect breeding in S. habrochaites and a new theoretical basis for the improvement of important traits in cultivated tomato.

Redox reactions in vitrified-warmed ovary

BACKGROUNDS

Ovary vitrification is a way for the preservation of fertility in women undergoing chemotherapy and for protecting the valuable or the endangered species. However, cryopreservation of complex tissues, which are composed of different cells and materials, encountered various challenges including oxidative stress damage.

OBJECTIVES

This study aimed to evaluate some oxidative stress indices in the vitrified bovine ovaries.

METHODS

The pieces of the bovine ovarian cortex (1 × 1 × 1 mm3) were vitrified with final concentrations of ethylene glycol (25%) and glycerol (25%) and 0.5 M sucrose and then, after 48 h, were warmed with descending concentrations (0.5, 0.25, and 0.125 M) of sucrose. The ovaries were processed and some biochemical indicators of oxidative stresses were assayed.

RESULTS

Total antioxidant capacity had a 45% decrease after vitrification (P<.0001). This reduction was associated with a 4 times increase in malondialdehyde (P=.0002) and a 53% decrease in superoxide dismutase (P=.0081). The levels of protein carbonyl in vitrified-warmed ovaries were less than in fresh ovaries (P=.0325). Regression analysis showed that the components of oxidative stress indices in vitrified tissues are different from those of fresh tissues.

CONCLUSION

An extensive alteration was seen in oxidant/antioxidant balance during vitrification.

Metabolic priming in G6PDH isoenzyme-replaced tobacco lines improves stress tolerance and seed yields via altering assimilate partitioning

We investigated the basis for better performance of transgenic Nicotiana tabacum plants with G6PDH-isoenzyme replacement in the cytosol (Xanthi::cP2::cytRNAi, Scharte et al., 2009). After six generations of selfing, infiltration of Phytophthora nicotianae zoospores into source leaves confirmed that defence responses (ROS, callose) are accelerated, showing as fast cell death of the infected tissue. Yet, stress-related hormone profiles resembled susceptible Xanthi and not resistant cultivar SNN, hinting at mainly metabolic adjustments in the transgenic lines. Leaves of non-stressed plants contained twofold elevated fructose-2,6-bisphosphate (F2,6P2 ) levels, leading to partial sugar retention (soluble sugars, starch) and elevated hexose-to-sucrose ratios, but also more lipids. Above-ground biomass lay in between susceptible Xanthi and resistant SNN, with photo-assimilates preferentially allocated to inflorescences. Seeds were heavier with higher lipid-to-carbohydrate ratios, resulting in increased harvest yields - also under water limitation. Abiotic stress tolerance (salt, drought) was improved during germination, and in floated leaf disks of non-stressed plants. In leaves of salt-watered plants, proline accumulated to higher levels during illumination, concomitant with efficient NADP(H) use and recycling. Non-stressed plants showed enhanced PSII-induction kinetics (upon dark-light transition) with little differences at the stationary phase. Leaf exudates contained 10% less sucrose, similar amino acids, but more fatty acids - especially in the light. Export of specific fatty acids via the phloem may contribute to both, earlier flowering and higher seed yields of the Xanthi-cP2 lines. Apparently, metabolic priming by F2,6P2 -combined with sustained NADP(H) turnover-bypasses the genetically fixed growth-defence trade-off, rendering tobacco plants more stress-resilient and productive.

G6PDH as a key immunometabolic and redox trigger in arthropods

The enzyme glucose-6-phosphate dehydrogenase (G6PDH) plays crucial roles in glucose homeostasis and the pentose phosphate pathway (PPP), being also involved in redox metabolism. The PPP is an important metabolic pathway that produces ribose and nicotinamide adenine dinucleotide phosphate (NADPH), which are essential for several physiologic and biochemical processes, such as the synthesis of fatty acids and nucleic acids. As a rate-limiting step in PPP, G6PDH is a highly conserved enzyme and its deficiency can lead to severe consequences for the organism, in particular for cell growth. Insufficient G6PDH activity can lead to cell growth arrest, impaired embryonic development, as well as a reduction in insulin sensitivity, inflammation, diabetes, and hypertension. While research on G6PDH and PPP has historically focused on mammalian models, particularly human disorders, recent studies have shed light on the regulation of this enzyme in arthropods, where new functions were discovered. This review will discuss the role of arthropod G6PDH in regulating redox homeostasis and immunometabolism and explore potential avenues for further research on this enzyme in various metabolic adaptations.

Individual and combinative effect of NaCl and γ-radiation on NADPH-generating enzymes activity in corn (Zea mays L.) sprouts

Being a universal reducing agent nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) plays an important role in the cellular metabolism and the implementation of anti-stress reactions in plants. There are only a few enzymes that ensure the NADPH pool formation in cells. Among them, the most important are glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49), malate dehydrogenase decarboxylating (DMDH, malic enzyme, EC 1.1.1.40) and NADP-isocitrate dehydrogenase (NADP-IDH, EC 1.1.1.42). The presented investigation is devoted to studying the influence of the individual and combinative effects of NaCl and γ-radiation as abiotic stress factors on biometric indicators and activity of these NADPH-generating enzymes, on organic content, and the formation of paramagnetic centers as defense reaction in corn (Zagatala-68 genotype) sprouts. It was found that 100 mM NaCl had an inhibitory effect on the development of sprouts. Relatively lower doses (50 Gy and 100 Gy) of γ-radiation had a positive, but its higher doses (150 Gy and 200 Gy) had a negative effect on this process. 500 Gy was a lethal dose (LD) for the corn sprouts. Combinative stress in all cases considerably delayed the development of sprouts. G6PDH showed the highest activity in the first, whereas, NADP-IDH showed the same activity in the last days of the experiment. All three enzymes, especially the G6PDH, have been activated in both root and stem tissues under the influence of stress factors (either radiation or salt). Combinative stress (γ-radiation + salt) also led to an induction of these activities which was necessary to neutralize the negative consequences of stress factors. Stress factors in all cases also had a negative effect on the content of organic matter in seedlings. Ionizing gamma radiation, which resulted in the formation of new paramagnetic centers as an anti-stress defense reaction in many cases was observed in wheat seedlings, but not in corn sprouts, which clearly shows that there are some differences in the protective mechanisms of these C3- and C4-types of plants to γ-radiation.

A new quantitative insight: Interaction of polyethylene microplastics with soil - microbiome - crop

In this study, the interaction between primary/secondary PE MPs and soil - microbiome - crop complex system and PE MPs enrichment behavior in crops were studied by using the self-developed quantitative characterization method of Eu-MPs and in situ zymography. The results demonstrated for the first time the enrichment effect of micron-sized PE (> 10 µm) in crops, manifested as roots>leaves>stems. Primary PE MPs significantly increased soil TN, TC, SOM and β-glu activity and inhibited Phos activity. Age-PE MPs significantly reduced soil TN, TP, β-glu and Phos activities and also have significant inhibitory effects on plant height, stem diameter, and leaf dry weight of maize. Age-PE MPs significantly affected soil microbial diversity, mainly caused by bacterial genera such as UTCFX1, Sphingomonas, Subgroup-6 and Gemmatimonas. Age-PE MPs also affected some metabolism related to microbial community composition and maize growth, including Glycerolipid, Citrate cycle (TCA cycle), C5-Branched dibasic acid, Arginine and proline, Tyrosine metabolism, pentose phosphate pathway, Valine, leucine and isoleucine biosynthesis. These research results indicated that the PE MPs, which are widely present in farmland soils, can affect crop growth, soil microbial community and metabolic function after aging, thus affecting agroecosystems and terrestrial biodiversity.

Mapping the castor bean endosperm proteome revealed a metabolic interaction between plastid, mitochondria, and peroxisomes to optimize seedling growth

In this work, we studied castor-oil plant Ricinus communis as a classical system for endosperm reserve breakdown. The seeds of castor beans consist of a centrally located embryo with the two thin cotyledons surrounded by the endosperm. The endosperm functions as major storage tissue and is packed with nutritional reserves, such as oil, proteins, and starch. Upon germination, mobilization of the storage reserves requires inter-organellar interplay of plastids, mitochondria, and peroxisomes to optimize growth for the developing seedling. To understand their metabolic interactions, we performed a large-scale organellar proteomic study on castor bean endosperm. Organelles from endosperm of etiolated seedlings were isolated and subjected to liquid chromatography-tandem mass spectrometry (LC-MS/MS). Computer-assisted deconvolution algorithms were applied to reliably assign the identified proteins to their correct subcellular localization and to determine the abundance of the different organelles in the heterogeneous protein samples. The data obtained were used to build a comprehensive metabolic model for plastids, mitochondria, and peroxisomes during storage reserve mobilization in castor bean endosperm.

Efficient sugar utilization and transition from oxidative to substrate-level phosphorylation in high starch storage roots of African cassava genotypes

Cassava's storage roots represent one of the most important sources of nutritional carbohydrates worldwide. Particularly, smallholder farmers in sub-Saharan Africa depend on this crop plant, where resilient and yield-improved varieties are of vital importance to support steadily increasing populations. Aided by a growing understanding of the plant's metabolism and physiology, targeted improvement concepts already led to visible gains in recent years. To expand our knowledge and to contribute to these successes, we investigated storage roots of eight cassava genotypes with differential dry matter content from three successive field trials for their proteomic and metabolic profiles. At large, the metabolic focus in storage roots transitioned from cellular growth processes toward carbohydrate and nitrogen storage with increasing dry matter content. This is reflected in higher abundance of proteins related to nucleotide synthesis, protein turnover, and vacuolar energization in low starch genotypes, while proteins involved in sugar conversion and glycolysis were more prevalent in high dry matter genotypes. This shift in metabolic orientation was underlined by a clear transition from oxidative- to substrate-level phosphorylation in high dry matter genotypes. Our analyses highlight metabolic patterns that are consistently and quantitatively associated with high dry matter accumulation in cassava storage roots, providing fundamental understanding of cassava's metabolism as well as a data resource for targeted genetic improvement.

Transcriptomic and targeted metabolomic unravelling the molecular mechanism of sugar metabolism regulating heteroblastic changes in Pinus massoniana seedlings

Pine seedling leaf characteristics show a distinct transition from primary to secondary needles, known as heteroblastic change. However, the underlying regulatory mechanism is poorly understood. The molecular mechanism of sugar metabolism involved in regulating heteroblastic changes in Pinus massoniana seedlings was investigated via transcriptomics and targeted metabolomics. The results identified 12 kinds of sugar metabolites in the foliage. Three types of sugar accumulated at the highest levels: sucrose, glucose and fructose. Compared to seedlings with only primary needles (PN), the contents of these soluble sugars were lower in seedlings with developing secondary needle buds (SNB). RNA-seq analysis highlighted 1086 DEGs between PN and SNB seedlings, revealing significant enrichment in KEGG pathways including starch and sucrose metabolism, plant hormone signal transduction and amino sugar and nucleic acid sugar metabolism. Combined transcriptomic and metabolomic analysis revealed that HK, MDH, and ATPase could potentially enhance sugar availability by stimulating the glycolytic/TCA cycle and oxidative phosphorylation. These processes may lead to a reduced sugar content in the foliage of SNB seedlings. We also identified 72 transcription factors, among which the expression levels of MYB, WRKY, NAC and C2H2 family genes were closely related to those of DEGs in the sugar metabolism pathway. In addition, we identified alternative splicing (AS) events in one NAC gene leading to two isoforms, PmNAC5L and PmNAC5S. PmNAC5L was significantly upregulated, while PmNAC5S was significantly downregulated in SNB seedlings. Overall, our results provide new insights into how sugar metabolism is involved in regulating heteroblastic changes in pine seedlings.

Iron uptake of etioplasts is independent from photosynthesis but applies the reduction-based strategy

Introduction

Iron (Fe) is one of themost important cofactors in the photosynthetic apparatus, and its uptake by chloroplasts has also been associated with the operation of the photosynthetic electron transport chain during reduction-based plastidial Fe uptake. Therefore, plastidial Fe uptake was considered not to be operational in the absence of the photosynthetic activity. Nevertheless, Fe is also required for enzymatic functions unrelated to photosynthesis, highlighting the importance of Fe acquisition by non-photosynthetic plastids. Yet, it remains unclear how these plastids acquire Fe in the absence of photosynthetic function. Furthermore, plastids of etiolated tissues should already possess the ability to acquire Fe, since the biosynthesis of thylakoid membrane complexes requires a massive amount of readily available Fe. Thus, we aimed to investigate whether the reduction-based plastidial Fe uptake solely relies on the functioning photosynthetic apparatus.

Methods

In our combined structure, iron content and transcript amount analysis studies, we used Savoy cabbage plant as a model, which develops natural etiolation in the inner leaves of the heads due to the shading of the outer leaf layers.

Results

Foliar and plastidial Fe content of Savoy cabbage leaves decreased towards the inner leaf layers. The leaves of the innermost leaf layers proved to be etiolated, containing etioplasts that lacked the photosynthetic machinery and thus were photosynthetically inactive. However, we discovered that these etioplasts contained, and were able to take up, Fe. Although the relative transcript abundance of genes associated with plastidial Fe uptake and homeostasis decreased towards the inner leaf layers, both ferric chelate reductase FRO7 transcripts and activity were detected in the innermost leaf layer. Additionally, a significant NADP(H) pool and NAD(P)H dehydrogenase activity was detected in the etioplasts of the innermost leaf layer, indicating the presence of the reducing capacity that likely supports the reduction-based Fe uptake of etioplasts.

Discussion

Based on these findings, the reduction-based plastidial Fe acquisition should not be considered exclusively dependent on the photosynthetic functions.

The mechanistic insights of the antioxidant Keap1-Nrf2 pathway in oncogenesis: a deadly scenario

The Nuclear factor erythroid 2-related factor 2 (Nrf2) protein has garnered significant interest due to its crucial function in safeguarding cells and tissues. The Nrf2 protein is crucial in preserving tissue integrity by safeguarding cells against metabolic, xenobiotic and oxidative stress. Due to its various functions, Nrf2 is a potential pharmacological target for reducing the incidence of diseases such as cancer. However, mutations in Keap1-Nrf2 are not consistently favored in all types of cancer. Instead, they seem to interact with specific driver mutations of tumors and their respective tissue origins. The Kelch-like ECH-associated protein 1 (Keap1)-Nrf2 pathway mutations are a powerful cancer adaptation that utilizes inherent cytoprotective pathways, encompassing nutrient metabolism and ROS regulation. The augmentation of Nrf2 activity elicits significant alterations in the characteristics of neoplastic cells, such as resistance to radiotherapy and chemotherapy, safeguarding against apoptosis, heightened invasiveness, hindered senescence, impaired autophagy and increased angiogenesis. The altered activity of Nrf2 can arise from diverse genetic and epigenetic modifications that instantly impact Nrf2 regulation. The present study aims to showcase the correlation between the Keap1-Nrf2 pathway and the progression of cancers, emphasizing genetic mutations, metabolic processes, immune regulation, and potential therapeutic strategies. This article delves into the intricacies of Nrf2 pathway anomalies in cancer, the potential ramifications of uncontrolled Nrf2 activity, and therapeutic interventions to modulate the Keap1-Nrf2 pathway.