Genomic variation drives phenotypic diversity, including individual differences in drug response. While coding polymorphisms linked to drug efficacy and adverse reactions are well characterized, the contribution of noncoding regulatory elements remains underexplored. Using CAGE (Cap Analysis of Gene Expression), profiling transcription initiations of mRNAs and enhancer RNAs, we identify candidate cis-regulatory elements (CREs) and assessed their activities simultaneously in HepG2 cells expressing the drug-responsive transcription factor pregnane X receptor (PXR). Comparison with GWAS data reveals strong enrichment of the drug-induced CREs near variants associated with bilirubin and vitamin D levels. Among those bound by PXR in primary hepatocytes, we identify enhancers of UGT1A1, TSKU, and CYP24A1 and functional alleles that alter regulatory activities. We also find that TSKU influences expression of vitamin D-metabolizing enzymes. This study expands the landscape of PXR-mediated regulatory elements and uncovers noncoding variants impacting drug response, providing insights into the genomic basis of adverse drug reactions.

Despite aggressive therapy, glioblastoma (GBM) recurs in almost all patients and treatment options are very limited. Despite our growing understanding of how cellular transitions associate with relapse in GBM, critical gaps remain in our ability to block these molecular changes and treat recurrent disease. In this study we combine computational biology, forward-thinking understanding of miRNA biology and cutting-edge nucleic acid delivery vehicles to advance targeted therapeutics for GBM. Computational analysis of RNA sequencing from clinical GBM specimens identified TGFβ type II receptor (TGFBR2) as a key player in the mesenchymal transition associated with worse outcome in GBM. Mechanistically, we show that elevated levels of TGFBR2 is conducive to reduced temozolomide (TMZ) sensitivity. This effect is, at least partially, induced by stem-cell driving events coordinated by the reprogramming transcription factors Oct4 and Sox2 that lead to open chromatin states. We show that blocking TGFBR2 via molecular and pharmacological approaches decreases stem cell capacity and sensitivity of clinical recurrent GBM (rGBM) isolates to TMZ in vitro. Network analysis uncovered miR-590-3p as a tumor suppressor that simultaneously inhibits multiple oncogenic nodes downstream of TGFBR2. We also developed novel biodegradable lipophilic poly(β-amino ester) nanoparticles (LiPBAEs) for in vivo microRNA (miRNAs) delivery. Following direct intra-tumoral infusion, these nanomiRs efficiently distribute through the tumors. Importantly, miR-590-3p nanomiRs inhibited the growth and extended survival of mice bearing orthotopic human rGBM xenografts, with an apparent 30% cure rate. These results show that miRNA-based targeted therapeutics provide new opportunities to treat rGBM and bypass the resistance to standard of care therapy.

Potato late blight is an important disease in potato production, which causes serious damage. Salicylic acid (SA) is a plant hormone involved in the regulation of potato (Solanum tuberosum) resistance to Phytophthora infestans. In this study, it was found that exogenous methyl salicylate (MeSA) treatment could significantly enhance the resistance of potato to P. infestans. RNA-seq results confirmed that SA was important for potato resistance to P. infestans. Salicylic acid binding protein 2 (SABP2) is a member of α/β hydrolase family, which can convert MeSA into SA to regulate the steady state of SA in plants. StSABP2 protein was obtained through prokaryotic expression, and enzymatic analysis in vitro confirmed that StSABP2 could transform MeSA into SA. In order to explore the function of StSABP2 in the process of plant resistance to P. infestans, we carried out virus-mediated gene silencing of StSABP2 in potato and transiently expressed StSABP2 in tobacco. The results showed that StSABP2 positively regulated plant resistance to P. infestans, and this process was achieved by mediating the transcription of SA signal and defence-related genes. Then we screened for the upstream regulator of StSABP2. The results of double luciferase and yeast one-hybrid analysis showed that StNAC2 could activate the transcription of StSABP2. The StNAC2-StSABP2 module regulated potato resistance to P. infestans by positively mediating the SA pathway. This study provides a new idea for improving host resistance to potato late blight by regulating the SA signal in potato and provides germplasm resources for potato resistance breeding.

Triple-negative breast cancer (TNBC) constitutes the molecular subtype exhibiting the poorest prognosis. Targeted therapy emerges as a pivotal strategy to enhance the clinical outcomes of individuals with TNBC. Identifying targets and corresponding therapeutic agents is essential for reducing TNBC-related mortality. Topotecan, a chemotherapeutic agent approved for treating metastatic breast cancer, remains under investigation regarding its specific targets and molecular mechanisms in TNBC. Data procured from CRISPR/Cas9 library screenings showed that TFDP1 may be a therapeutic target in TNBC, and the L1000FWD database suggested that TFDP1 serves as a potential target of topotecan. The overexpression of TFDP1 was observed in TNBC tissues, correlating with poorer prognosis. Knockdown of TFDP1 inhibited the cell growth, clonal expansion, and tumorigenicity of TNBC cells. Mechanistically, TFDP1 inhibited cellular senescence in TNBC cells. In vitro experiments demonstrated that topotecan inhibited TNBC cell growth and promoted cellular senescence, counteracting the effects of TFDP1 overexpression on TNBC cells. These findings suggest that topotecan impedes TNBC cell growth by targeting TFDP1. This interaction provides valuable insights into the molecular mechanisms governing TNBC cell senescence, presenting TFDP1 as a potential therapeutic target. Combining topotecan with senolytic therapies may offer a promising strategy for TNBC treatment.

Most subgroup S1 basic leucine zipper (bZIP) transcription factors (TFs) play a crucial role in the abiotic stress responses. However, their functions and molecular mechanisms remain poorly characterized in wheat (Triticum aestivum L.). In this study, we identified a novel subgroup S1 bZIP gene, designated TabZIP11-D, which was transcriptionally responsive to abscisic acid (ABA), salt, and cold stresses. TabZIP11-D encodes a nuclear-localized protein that lacks transcriptional activation activity in yeast. The Ca2+ blocker LaCl3 significantly suppressed the salt-induced expression of TabZIP11-D. TabZIP11-D interacted with the Ca2+-dependent protein kinases (TaCDPK1, TaCDPK5, TaCDPK9-1, and TaCDPK30) and the CBL-interacting protein kinase TaCIPK31. Overexpression of TabZIP11-D enhanced salt and freezing tolerance by modulating soluble sugar and proline accumulation, reducing hydrogen peroxide (H2O2) and malondialdehyde (MDA) contents, and regulating the expression levels of stress-responsive genes. Furthermore, TabZIP11-D formed a homodimer with itself and heterodimers with group C bZIP proteins. Modified yeast one-hybrid assays revealed that TabZIP14 and TabZIP36 significantly enhanced TabZIP11-D binding to the G-box cis-element in the promoter region of TaCBF1 gene. These findings demonstrate that TabZIP11-D heterodimerizes with TabZIP14/36 to regulate cold signaling by promoting the TaCBF1 transcription. TabZIP11-D functions as a positive regulator in the salt stress response by interacting with TaCDPK1/5/9-1/30 and TaCIPK31.

Fusarium oxysporum (F. oxysporum) is one of the main pathogenic fungus causing maize ear rot. In this study, the aims were to screen highly effective pesticides for F. oxysporum, reduce peasants' misunderstandings about pesticide application, improve disease control levels, and enhance economic efficiency. The toxicity of seven fungicides (carbendazim, pyraclostrobin, epoxiconazole, tricyclazole, azoxystrobin, difenoconazole, quintozene) on F. oxysporum were determined by the mycelium growth rate and the spore germination method, and single and compound fungicides with effective inhibitory effects on mycelial growth were screened. The RT-qPCR method was used to detect the expression levels of chitin synthetase V (ChsV), folate uptake block T (FUBT), superoxide dismutase (SOD), and peroxidase dismutase (POD) genes in pathogenic bacteria treated with the selected agents and combination of fungicides. The results showed that all seven fungicides had inhibitory effects on mycelial growth hyphae and spore germination of F. oxysporum. Epoxiconazole had the strongest inhibitory effect on mycelium growth and spore germination of F. oxysporum, with effective concentrations (EC50) of 0.047 and 0.088 μg/mL, respectively. The combination of pyraclostrobin and difenoconazole (P&D, combined at a mass ratio of 7:3) had the best inhibitory effect, with an EC50 of 0.094 μg/mL and an SR of 2.650. Epoxiconazole and the combination P&D could inhibit mycelial growth and spore germination by down-regulating ChsV, FUBT, and POD, causing oxidative stress in F. oxysporum, and reducing the occurrence of maize ear rot.

The degradation of marine plastic debris poses a threat to organisms by fragmenting into micro- and nano-scale pieces and releasing a complex chemical leachate into the water. Numerous studies have investigated harms from plastic pollution such as microplastic ingestion and exposure to single chemicals. However, few studies have examined the holistic threat of plastic exposure and the synergistic impacts of chemical mixtures. The objective of this study was to measure changes in gene expression of gill and gonadal tissue of the eastern oyster (Crassostrea virginica) in response to plastic debris exposure during their first year, using RNA-seq to explore multiple types of physiological responses. Shell and polyethylene terephthalate plastic were used as substrate for the metamorphosis of larval oysters in a settlement tank. Substrate pieces were then transferred to metal cages and outplanted in pairs - shell cage and plastic cage - onto restoration reefs in the St. Mary's River, Maryland, USA. After 10 months of growth, the oysters were collected, gill and gonadal tissue removed, and sex identified. The tissues of six oysters from each sex and substrate type were then analyzed in RNA-seq. Both gill and gonadal tissue samples had altered expression of immune and stress-response genes in response to plastic exposure. Genes upregulated in response to plastic were enriched for gene ontology functions of proteolysis and fibrinolysis. Downregulated genes were involved in shell biomineralization and growth. One male oyster exposed to plastic had "feminized" gene expression patterns despite developing mature sperm, suggesting plastic leachate can alter gene expression and shift protandric individuals to develop as females. Plastic pollution may therefore reduce shell growth, initiate immune and stress responses, alter sex differentiation, and impact reproductive output of eastern oysters through changes in transcription.

A20, a negative regulator of NF-κB signaling, is a potent anti-inflammatory molecule. Its deficiency is associated with a wide variety of inflammatory diseases and tumors and the ability of A20 to restrict TCR-NF-κB signaling pathway and the role of this molecule in the pathogenesis of T-cell leukemia are not completely understood. Here we studied the role of A20 in T cells exposed to staphylococcal enterotoxin A (SEA) and evaluated the results of our in vitro findings of lethal inflammation by long-term administration of SEA at low doses to Jurkat cells, human peripheral blood mononuclear cells, and CD3+ T cells. SEA treatment resulted in chronic inflammation, upregulated the expression of MALT1, IKKβ, and p65, and downregulated the expression of A20, both in dose- and time-dependent manners, in Jurkat cells, regardless of the mRNA or protein level. Thus, SEA-mediated chronic inflammation can activate TCR-NF-κB signals via the downregulation of A20 expression, which increases T-cell immortality and may promote the pathogenesis of T-cell leukemia. Modulation of A20 could be a novel strategy for the treatment of T-cell leukemia.

The phenotypic switch of vascular smooth muscle cells (VSMCs), characterized by the tissue-specific expression of certain microRNAs (miRNAs), is a critical factor in the development of diabetic vascular diseases. Metformin, a widely prescribed anti-diabetic medication for type 2 diabetes treatment, activates the adenosine monophosphate-activated protein kinase (AMPK) pathway and exerts a protective effect on vascular endothelium. Although the regulatory effects of metformin on the switch of the vascular smooth muscle cell phenotype have been identified, the specific role of miRNAs in this process remains unclear. We identified a specific miR-1 in response to metformin treatment and determined its effects on both miR-1 and its targets. Subsequently, we investigated the influence of these factors on the metformin-induced phenotype switch in vascular smooth muscle cells, specifically focusing on proliferation and migration, as well as activation of the AMPK/Transforming Growth Factor (TGF-β) axis. This was achieved using various methodologies, including bioinformatics analysis, quantitative real-time polymerase chain reaction (qRT-PCR), Western blot analysis, wound scratch assays, and Cell Counting Kit-8 assays. Our findings showed that metformin upregulated miR-1, which directly targets cyclin D1 (CCND1) in VSMCs. Metformin was observed to enhance the expression of contractile phenotype proteins, including α-smooth muscle actin (α-SMA) and smooth muscle myosin heavy chain (SMMHC), while simultaneously reducing the expression of proliferative phenotype proteins such as CCND1 and proliferating cell nuclear antigen (PCNA). The inhibition of miR-1 was found to reverse the effects of metformin on the phenotypic switch of VSMCs. This occurs partly through the AMPK/TGF-β signaling pathway and inhibits the migration and proliferation of VSMCs.

Transcriptome proteome association analysis screened candidate DEGs, DEPs, and DEGs/DEPs associated with potato response to drought, alkali, and combined stresses. Overexpression of StCOMT1 enhances potato drought and alkali tolerance. Drought and salinity have severely impeded potato (Solanum tuberosum L.) growth and development, significantly reducing global potato production. However, the molecular mechanisms regulating the combined drought and alkali stress process are not fully understood. This study compared the mRNA and protein expression profiles of potato under drought (PEG-6000), alkali (NaHCO3), and combined (PEG-6000 + NaHCO3) stresses by transcriptome and TMT proteomics sequencing to investigate the common or specific responses of 'Atlantic' potato to single and combined stresses of drought and alkali were preliminarily explored. It was found that 2215 differentially expressed genes (DEGs) and 450 differentially expressed proteins (DEPs) were jointly identified under drought, alkali, and combined stresses. Under drought, alkali, and combined stresses, 234, 185, and 246 DEGs/DEPs were identified, respectively. These DEGs, DEPs, and DEGs/DEPs identified revealed the potential roles of several signaling and metabolic pathways in mediating drought and alkali stress tolerance, including plant hormone signaling, MAPK signaling pathway, phenylpropanoid biosynthesis, and glutathione metabolism. Caffeic acid-O-methyltransferase (COMT) is an essential methylating enzyme in the phenylpropane biosynthetic pathway, which is involved in lignin synthesis and plays an important role in protecting plants from abiotic stresses. In this study, we investigated the changes in physiologic characteristics, such as growth, antioxidant defense, osmotic regulation and lignin accumulation, in overexpressing StCOMT1 (PT0001512/M0ZIL7) transgenic potato after stress. It proved that the gene has the function of adapting to drought and alkali stress, and provided a theoretical basis for further research on the resistance mechanism of the gene in drought and alkali tolerance in potato.

Anthracnose caused by Colletotrichum truncatum severely impacts global fruit/vegetable yields. Unlike other Colletotrichum species, C. truncatum exhibits inherent resistance to some sterol demethylation inhibitors (DMIs), necessitating an understanding of ergosterol synthesis regulation and resistance mechanisms. A transcription factor, CtSR (CTRU02_06681), that regulates the DMI sensitivity in C. truncatum was identified in our study. Deletion of CtSR rendered a naturally resistant isolate highly sensitive to DMIs, significantly reduced total ergosterol levels, decreased CYP51s expression compared to the wild type, and abolished DMI-induced expression of CYP51s. Deletion of CtSR reduced mycelial growth and virulence and made the strain highly sensitive to oxidative stress but did not affect its sensitivity to osmotic stress. Transcriptomic analysis and yeast one-hybrid assays confirmed that CtSR directly binds the conserved promoter motif CGAATACGAA to regulate ergosterol biosynthesis genes. Taken together, our study demonstrates a critical role for CtSR in the regulation of ergosterol biosynthesis and DMI interactions in C. truncatum, which may have significant practical implications.

Oxidative stress is one of the major methods of microbial population control and pathogen clearing by the mammalian immune system. The methods by which bacteria are able to escape damage by host-derived oxidants such as hydrogen peroxide (H2O2) and hypochlorous acid (HOCl) have been relatively well described, while other oxidants' effects on bacteria and their genetic responses are not as well understood. Hypothiocyanite/hypothiocyanous acid (OSCN-/HOSCN) is one such oxidative stress agent. In this study, we used RNA-sequencing to characterize the global transcriptional response of Escherichia coli to treatment with HOSCN and the impact of deletions of the HOSCN resistance proteins RclA (HOSCN reductase), RclB, and RclC on that response. The HOSCN response of E. coli was different from the previously characterized responses of E. coli to other oxidants such as H2O2, superoxide, or HOCl and distinct from the reported responses of other bacteria such as Streptococcus pneumoniae and Pseudomonas aeruginosa to HOSCN. Strikingly, deletion of any one of the Rcl proteins had very similar effects on the transcriptional response to HOSCN, indicating that any disruption of HOSCN defense in E. coli results in similar impacts, despite the fact that we do not currently understand the mechanism(s) by which RclB and RclC contribute to that defense.

Adeno-associated virus (AAV) gene therapies typically use constitutive transgene expression vectors that cannot be altered after vector administration. Here, we describe a bioorthogonal platform for tuning AAV expression which enables the controlled activation of viral transgenes after transduction. This platform uses a small, synthetic DNA-binding protein embedded in the AAV genome coupled with a heterobifunctional small molecule that recruits endogenous transcriptional machinery to chemically induce transgene expression in a dose-dependent and reversible manner. In human cells, this strategy successfully activates AAV expression across different viral serotypes, cassette configurations, and transgene payloads. Epigenomic analysis reveals that this technology facilitates direct and specific recruitment of the transcriptional regulator BRD4 to AAV genomes. Our results demonstrate that the expression of native AAV genomes can be tuned through chemically induced proximity, opening the possibility of a new class of AAV vectors that can be dynamically potentiated.

Hepatocellular carcinoma (HCC) continues to pose a substantial worldwide health concern, marked by elevated mortality rates and restricted therapeutic alternatives. Recent studies have highlighted the potential of natural compounds as therapeutic agents in cancer management. This review focuses on the diagnostic and prognostic potential of microRNAs (miRNAs) as biomarkers in HCC, alongside the therapeutic promise of natural products. We explore the intricate role of miRNAs in the pathogenesis of HCC, detailing their regulatory functions in cellular processes such as proliferation, apoptosis, and metastasis. Additionally, we discuss the emerging evidence supporting the use of natural compounds, including phytochemicals, in modulating miRNA expression and their potential synergistic effects with conventional therapies. Key miRNAs discussed include miR-21, an oncogenic factor that promotes tumor growth by targeting the tumor suppressor phosphatase and tensin homolog (PTEN); miR-34a, which enhances apoptosis and may improve treatment efficacy when combined with c-MET inhibitors; miR-203, whose downregulation correlates with poor outcomes and may serve as a prognostic marker; miR-16, which acts as a tumor suppressor and has diagnostic potential when measured alongside traditional markers like alpha-fetoprotein (AFP); and miR-483-3p, associated with resistance to apoptosis and tumor progression. By integrating insights from recent studies, this review aims to highlight the dual role of miRNAs as both biomarkers and therapeutic targets, paving the way for enhanced diagnostic strategies and novel treatment modalities in HCC management.

The breast cancer recurrence and chemoresistance has increased over the years. A novel PKC, PKCε, may promote chemoresistance by causing hypoxia and cancer metabolic rewiring. A natural flavonoid, Zapotin, in colon cancer cells may modulate PKCε expression. Therefore, this study aimed to explore Zapotin impact on PKCε expression and the metabolic profile of breast cancer cells.

TiO2 nanoparticles mitigates the toxicity of Cd to Hemerocallis citrina Baroni (daylily) by modulating the photosynthetic and antioxidative system, as revealed by physiological and transcriptomic analysis. Cadmium (Cd) is a common heavy metal pollutant exerting toxicity to plants. The unique physiochemical properties of titanium dioxide nanoparticles (TiO2 NPs) suggest their potential applications in agriculture. The molecular and physiological responses of Hemerocallis citrina Baroni (daylily) to Cd stress and the ameliorative effect of TiO2 NPs were investigated. KEGG enrichment analysis on differentially expressed genes (DEGs) revealed pronounced enrichment of pathways related to photosynthesis. GO enrichment analysis showed that chlorophyll metabolism and redox process were also notably enriched. Furthermore, weighted gene co-expression network analysis (WGCNA) demonstrated remarkable responses of photosynthetic characteristics and antioxidative system, and identified MYB, NAC, and WRKY transcription factors which played key roles in the Cd-stress response and regulation by TiO2 NPs. Under 5 mmol·L-1 Cd stress, daylily growth was severely inhibited, and cell membrane permeability and osmolytes significantly increased. Additionally, Cd stress pronouncedly impaired photosynthesis, increased the accumulation of reactive oxygen species in leaves, and inhibited the activities of most antioxidants. However, foliar spraying of 200 mg·L-1 TiO2 NPs promoted plant growth and increased osmolytes. The inhibition on leaf photosynthetic antenna proteins, photosystem reaction center activity, electron transfer rate, chlorophyll synthesis, and Calvin cycle process was markedly alleviated by upregulating corresponding gene expression as revealed by photosynthesis-related traits and DEG analysis. The activities of key enzymes in ascorbate-glutathione (AsA-GSH) cycle and thioredoxin-peroxiredoxin (Trx-Prx) pathway were enhanced, and the regeneration of AsA and GSH was promoted. Overall, TiO2 NPs mitigated Cd-induced inhibition of photosynthesis and antioxidative system, and enhanced Cd tolerance of daylily.

Gastric cancer (GC) is a leading cause of cancer-related deaths worldwide. MicroRNAs (miRNAs) are key regulators of tumorigenesis. This study investigated the role of the miR-192/215-early growth response protein 1 (EGR1) axis in GC and explored its therapeutic implications.

To elucidate the inhibitory mechanism of antimicrobial peptide WK-13-3D on triple-negative breast cancer (TNBC) by targeting the binding immunoglobulin protein (BiP), a key endoplasmic reticulum (ER) chaperone regulating unfolded protein response and tumor survival.

Schwann cells dysfunction is a key contributor to diabetic peripheral neuropathy (DPN), affecting both neurons and blood vessels. However, the precise mechanisms underlying high glucose-induced Schwann cells dysfunction are still not fully elucidated. In the present study, we investigated the expression, function and molecular mechanisms of SDF2L1 in Schwann cells using diabetic mice, SDF2L1 KO mice, rat Schwann cell (RSC96) and primary rat Schwann cell (PRSC). The RNA-seq of high glucose-treated RSC96 cells revealed an evident downregulation of SDF2L1 at both 48 and 72 h. The inhibition of high glucose on SDF2L1 expression was further confirmed at the levels of mRNA and protein in RSC96 and PRSC cells. Again, reduced SDF2L1 expression was also observed in the sciatic nerves of both type 1 and 2 diabetic mice. Functional exploration revealed that SDF2L1 knockdown in RSC96 cells suppressed the expression of LC3-II, P62, BDNF, NGF and IGF. In vivo SDF2L1 KO also decreased these proteins expression in the sciatic nerve of C57BL/6 J mice, along with the reduced nerve conduction velocity and action potential amplitude. Then, proteomics analyses and biological experiments demonstrated that SDF2L1 knockdown significantly decreased KPNA3 expression in RSC96 cells. Overexpression of KPNA3 ameliorated the decreases in LC3-II, P62, BDNF, NGF and IGF caused by SDF2L1 downregulation in vitro. Moreover, KPNA3 affected the nuclear import of transcription factors TFEB and CREB in RSC96 cells. Next, KPNA3 overexpression reversed SDF2L1 KO-reduced the nuclear aggregation of TFEB and CREB, and the expression of LC3, P62, BDNF and NGF in vivo. Collectively, these findings suggest that decreased SDF2L1 inhibits cell autophagy and neurotrophin expression by impeding the nuclear import of TFEB and CREB via KPNA3 downregulation in high glucose-treated Schwann cells.

Lactase peptide maintains food quality and ectoine stabilizes cell structure and function. The present study investigated the synergistic effect of 0.5 % lactopeptide and 0.1 % ectoine on preserving the quality of pak choi stored at 20 °C and 90 % relative humidity (RH) for 6 d. Results indicated that the combined treatment significantly reduced weight loss, electrolyte leakage, respiration rate, and ethylene generation compared to the untreated control or pak choi treated with ectoine. Furthermore, the combined treatment enhanced the level of ascorbic acid and flavonoids, and increased superoxide dismutase (SOD) activity. A combined transcriptomic and metabolomic analysis revealed the upregulation of key genes encoding proteins involved in the chlorophyll biosynthesis pathway, including protochlorophyllide reductase (POR), divinyl chlorophyllide a 8-vinyl-reductase (DVR), and chlorophyll/bacteriochlorophyll a synthase (CHLG), while the expression of the gene encoding a chlorophyll-degrading enzyme, chlorophyll (ide) b reductase (NOL), was suppressed. The combined treatment increased the abundance of metabolites associated with the citrate cycle pathway, including L-glutamate, L-glutamine, and L-asparagine. Additionally, the expression of chalcone isomerase (4CL), naringenin 3-dioxygenase (F3H) and chalcone synthase (CHS) in the phenylalanine, tyrosine, and tryptophan biosynthesis pathways, was elevated compared to the untreated control, resulting in increased levels of luteolin and naringenin chalcone. Collectively, our results indicate that the combined use of ectoine and lactopeptide effectively delayed the yellowing and postharvest senescence of pak choi during storage. The present study provides a foundation for further investigations of the postharvest metabolism of pak choi.