Search Results (1,727)

Resistance to 5-fluorouracil (5-FU) and oxaliplatin (OXA) remains an obstacle in colorectal cancer (CRC) therapy, but the upstream mechanisms enabling adaptive survival remain unclear. Angiomotin (AMOT), a Hippo-YAP regulator, is expressed as two major isoforms, p130 and p80, but the contribution of isoform-specific AMOT regulation to chemoresistance is unknown. RNA-seq of OXA-resistant cells identified AMOT as a candidate determinant, and its isoform-specific regulation and functional relevance were then examined in OXA- and 5-FU-resistant CRC sublines. AMOT-p80 was preferentially upregulated, whereas AMOT-p130 remained largely unchanged. Common AMOT pre-mRNA was elevated, whereas p130-specific pre-mRNA was unchanged, consistent with preferential transcriptional activation favoring the p80 isoform. Functionally, AMOT depletion minimally affected basal viability but significantly sensitized resistant cells to 5-FU or OXA, with increased apoptotic responses. AMOT silencing reduced nuclear YAP and lowered c-Myc and Cyclin D1 protein levels, whereas AMOT-p80 re-expression restored nuclear YAP, with recovery of c-Myc/Cyclin D1 levels and drug tolerance. YAP knockdown attenuated these outputs and blunted the additional effect of AMOT depletion. AMOT-p80 overexpression in parental cells increased c-Myc/Cyclin D1 protein levels and enhanced tolerance to 5-FU and OXA. These findings suggest that preferential AMOT-p80 upregulation is linked to YAP-associated chemoresistant phenotypes in CRC cells. Full article

Powdery mildew in wheat, caused by the biotrophic fungus Blumeria graminis f. sp. tritici (Bgt), is a major threat to global wheat production, yet the molecular mechanisms underlying differential cultivar resistance remain largely unresolved. In this study, tandem mass tag (TMT)-based quantitative proteomics was employed to investigate protein dynamics in resistant (Yannong37) and susceptible (Yannong1766) wheat cultivars at 0 and 24 h following Bgt inoculation. A total of 276 proteins exhibited significant changes in abundance after infection, with enrichment in cell wall and plasmodesmata-associated proteins. Comparative analysis further identified 456 differentially expressed proteins between the two cultivars at 24 h post-inoculation. Protein–protein interaction network analysis indicated that proteins involved in secondary metabolism and immune responses form coordinated regulatory networks contributing to disease resistance. RT–qPCR validation supported the reliability of the proteomic data. Notably, TaCAD-A1 displayed higher transcript abundance in the resistant cultivar and was associated with reduced fungal biomass accumulation. Silencing of TaCAD-A1 resulted in decreased expression of multiple defense-related genes. Collectively, these findings suggest that TaCAD-A1 may positively contribute to wheat resistance against Bgt infection and may be associated with defense responses and monolignol biosynthesis-related processes. Full article

Argonaute (AGO) proteins are central components of RNA silencing. While OsAGO18 is a known defense factor in antiviral immunity, its involvement in basal development and its transcriptomic behavior during fungal stress remains to be fully elucidated. In this study, based on its specific dual-localization in chloroplasts and processing bodies (P-bodies), we investigated the pleiotropic effects of OsAGO18 through transcriptomic network analysis of rice responding to the blast fungus Magnaporthe oryzae B.C. Couch. Our analysis revealed that the OsAGO18-mediated co-expression network is highly correlated with ribosome biogenesis and cell wall organization. Notably, the analyzed datasets reveal that this growth-related network is significantly suppressed upon M. oryzae challenge, highlighting a transcriptomic shift in OsAGO18 during the growth-to-defense transition. Phenotypic evaluations demonstrated that OsAGO18 overexpression accelerates early seedling growth and primary root elongation by promoting endogenous indole-3-acetic acid (IAA) accumulation, whereas ago18 mutants maintain basal growth rates without significant IAA fluctuations, reflecting robust genetic compensation within the highly redundant AGO family. Mechanistically, our integrated analysis suggests that OsAGO18 acts as a putative molecular decoy to sequester miR396d, thereby relieving the repression of the Growth-Regulating Factor OsGRF6 and triggering downstream auxin-dependent cascades. Collectively, our findings highlight OsAGO18 as a pivotal regulator of early seedling development and characterize its transcriptomic responsiveness to biotic stress, providing a plausible molecular link between post-transcriptional RNA regulation and rice growth coordination. Full article

Heat stress (HS), increasingly intensified by climate change, severely restricts tomato growth and productivity. Although core heat shock factor-mediated transcriptional networks have been extensively characterized, how lipid metabolic reprogramming is transcriptionally coordinated during thermotolerance remains unclear. Using SlHDZ19 overexpression and mutant lines together with transcriptomic, biochemical, promoter-binding, and gene-silencing analyses, we show that the homeobox-leucine zipper transcription factor SlHDZ19 promotes tomato (Solanum lycopersicum) thermotolerance by activating a PLA2-dependent lipid-metabolic transcriptional program in leaves. SlHDZ19 overexpression generally improved heat-stress performance, while SlHDZ19 mutant lines exhibited heightened sensitivity, including more severe wilting, higher electrolyte leakage, and reduced proline accumulation and CAT activity under heat stress. Transcriptomic analysis revealed that SlHDZ19 is required for the full induction of canonical heat-responsive genes and that the linoleic acid metabolism pathway was repeatedly implicated in SlHDZ19-dependent transcriptional changes. SlHDZ19 binds to and activates the promoters of SlPLA_2α, which encodes a phospholipase A2 involved in releasing linoleic acid from membrane lipids, and three lipoxygenase genes (SlLox7, SlLox8, and SlLoxC), accompanied by elevated overall PLA2 and LOX activities in SlHDZ19-overexpressing plants. Moreover, genetic silencing of SlPLA_2α in both wild-type and SlHDZ19-overexpressing backgrounds supported its functional requirement downstream of SlHDZ19 in thermotolerance. Collectively, our findings support a thermotolerance module in which SlHDZ19 transcriptionally regulates PLA2- and LOX-associated steps of linoleic acid metabolism, potentially linking lipid-associated signaling and membrane remodeling with heat stress adaptation in tomato. Full article

Background/Objectives: Epigenetic regulation plays a fundamental role in controlling the spatiotemporal expression of genes in plants under stressful environmental conditions. While LIKE HETEROCHROMATIN PROTEIN 1 (LHP1) is known to be involved in histone modification, its function in regulating the biosynthesis of specialized metabolites, particularly monoterpenoid indole alkaloids (MIAs) in Catharanthus roseus, remains elusive. Methods: CrLHP1 was identified by mining the C. roseus proteome and characterized through sequence alignment, phylogenetic analysis, and conserved domain assessment. Virus-induced gene silencing (VIGS) was employed to suppress CrLHP1 expression, after which the transcript levels of jasmonic acid (JA)-responsive genes and key MIA biosynthetic genes, as well as the accumulation of vindoline and catharanthine, were analyzed. Furthermore, deep learning-based protein structure prediction (AlphaFold3) and yeast two-hybrid (Y2H) assays were conducted to explore protein-protein interactions. Results: CrLHP1 was confirmed as the ortholog of Arabidopsis thaliana LHP1 (AtLHP1). Exposure to 75 μM MeJA upregulated MIA upstream pathway genes while downregulating CrLHP1 transcription. Silencing CrLHP1 significantly upregulated JA-responsive and MIA biosynthetic genes, leading to enhanced catharanthine accumulation. Additionally, the structural prediction and Y2H assays revealed a physical interaction between CrLHP1 and CrJAZ1. Conclusions: These findings suggest that CrLHP1 negatively regulates MIA biosynthesis, potentially by modulating JA signal transduction through interaction with CrJAZ1. This study provides new insights into the possible epigenetic mechanisms governing alkaloid production in C. roseus. Full article

The grain aphid, Sitobion miscanthi, poses a serious threat to cereal crops worldwide, leading to considerable yield losses and demanding annual insecticide applications during the grain-filling stage. As a sustainable alternative, we explored host-induced gene silencing (HIGS) targeting an aphid-specific gene. In this study, we identified SmDSR32, a novel gene encoding a salivary peptide in S. miscanthi, and validated its suitability for RNAi. Transgenic wheat lines expressing SmDSR32-dsRNA were generated. Aphids feeding on these lines showed a 20-fold reduction in SmDSR32 transcript levels compared with controls. This silencing disrupted normal feeding behavior in electropenetrography (EPG) analyses, characterized by a 1.94-fold prolongation of intercellular probing and a 61% shortening of phloem ingestion. Consequently, aphid performance was severely compromised, with at least a 56.7% decrease in survival, a shortening of 5 days in lifespan, and a reduction of 9–10 individuals in aphid progeny production. Impressively, upon being transferred to wild-type plants, both the surviving aphids and their progeny sustained fitness deficits, with a 30% reduction in survival still observed in the first generation. These findings validate SmDSR32 as a potent RNAi target and establish HIGS targeting essential salivary genes as a promising strategy for sustainable aphid management in wheat. Full article

Cotton Verticillium wilt (VW), caused by the soil-borne fungus Verticillium dahliae (V. dahliae), is a devastating disease that poses a serious threat to sustainable cotton production worldwide. Protein methylation plays a critical role in fungal adaptation to the host environment and manipulation of plant immunity. Protein arginine methyltransferases (PRMTs) are key enzymes catalyzing arginine methylation, yet their functions in V. dahliae pathogenicity remain largely unexplored. In this study, we identified VdPRMT4 in V. dahliae through homology-based screening. qRT-PCR analysis revealed that VdPRMT4 transcript levels were significantly increased during the early stages of V. dahliae infection in cotton. HIGS assays showed that silencing VdPRMT4 markedly alleviated cotton VW symptoms and reduced fungal biomass in cotton plants. Gene knockout and complementation experiments demonstrated that deletion of VdPRMT4 did not affect hyphal growth but significantly impaired sporulation capacity and severely attenuated pathogenicity on cotton. Transcriptomic analysis further indicated that loss of VdPRMT4 profoundly affected the metabolic pathways of V. dahliae, including protein processing in the endoplasmic reticulum, purine metabolism, and glycerolipid metabolism. Collectively, this study provides the first evidence that VdPRMT4 plays a critical role in stress adaptation and pathogenicity of V. dahliae, offering new insights into fungal pathogenesis and identifying potential targets for VW control. Full article

Ultraviolet radiation (UVR) exposure accelerates skin aging by disrupting cellular homeostasis and inducing epigenetic changes, such as promoter hypermethylation of key regulatory genes. However, the molecular mechanisms underlying UVR-driven epigenetic silencing remain poorly understood. By integrating high-throughput DNA methylation profiling with co-regulatory network analysis, we identified KIT as a hub gene in a photoaging-associated methylation module. Pathway enrichment further revealed coordinated hypermethylation of the canonical Wnt/β-catenin signaling pathway, establishing the Wnt/KIT axis as a critical epigenetic-signaling nexus in UVR-induced skin fibroblast aging. In immortalized human skin fibroblasts (HSFs), UVR suppressed Wnt signaling, leading to KIT promoter hypermethylation, transcriptional silencing, and premature photoaging. Gain-of-function studies revealed that reversing KIT hypermethylation either via Wnt pathway activation or KIT overexpression effectively mitigated photoaging-associated phenotypes. Crucially, we found that puerarin (PUE), a natural isoflavone, reversed UVR-induced epigenetic silencing by directly interacting with β-catenin, reactivating Wnt signaling, and restoring KIT expression. PUE treatment preserved cellular function in UVR-damaged fibroblasts. These findings establish the Wnt/β-catenin-KIT axis as a critical epigenetic driver of skin aging and highlight puerarin as a promising therapeutic candidate for targeted anti-aging intervention. Full article

High-temperature stress severely limits the growth, development, and productivity of tomatoes. Understanding the molecular mechanisms underlying its thermotolerance is crucial for breeding heat-resistant varieties. This study employed a stepwise experimental strategy to systematically elucidate the role of the chlorophyll a/b-binding protein SlCAB3 in tomato thermotolerance. First, a high-temperature responsive transcription factor, SlDREBA4, previously identified in our lab, was used in a yeast two-hybrid screen to identify potential interacting proteins, including SlCAB3. The interaction between SlDREBA4 and SlCAB3 was further validated using tobacco in vivo luciferase complementation imaging (LCI) and in vitro pull-down assays. Subsequently, the expression patterns of SlCAB3 under heat stress were analyzed, and its biological function was further evaluated through overexpression, gene silencing, and knockout experiments. Additionally, reactive oxygen species (ROS) accumulation, antioxidant enzyme activities, chlorophyll content, and the expression of stress-responsive genes were measured to comprehensively assess their physiological and molecular regulatory roles. The results indicate that SlCAB3 encodes a typical chlorophyll a/b-binding protein and is rapidly induced by heat stress. Overexpression of SlCAB3 significantly enhances plant thermotolerance, evidenced by reduced heat damage, increased chlorophyll content, decreased ROS accumulation, elevated antioxidant enzyme activities, and upregulation of antioxidant-related genes. Conversely, silencing SlCAB3 produces opposite effects. Moreover, co-expression of SlCAB3 with SlDREBA4 further improves thermotolerance, accompanied by enhanced expression of heat shock protein-related and antioxidant-related genes. In conclusion, SlCAB3 is a positive regulator of tomato thermotolerance, and the interaction module formed with SlDREBA4 may collectively enhance heat resistance by strengthening antioxidant defense and heat stress response mechanisms. Full article

Root knot nematodes (RKNs) induce galls, containing multinucleated giant cells (GCs) to nourish them. The differentiation of precursor cells to galls/GCs involves extensive cellular reprogramming with multiple layers of regulation. Epigenetic regulation during the early stages of infection indicates that RNA-directed DNA methylation (RdDM) and microRNA-dependent gene silencing contribute to transcriptional and post-transcriptional reprogramming during gall organogenesis. Although later stages of galls/GC development are crucial for nematode life-cycle maintenance, epigenetic reprogramming events remain largely unexplored. An integrative analysis of sRNAs, DNA methylation, and transcriptomic dynamics in galls induced by Meloidogyne javanica revealed that enrichment of 24 nt sRNAs represents a gall hallmark across early and late developmental stages. Fewer gall-distinctive sRNAs were detected at mid-to-late stages than at early stages, alongside a pronounced spatial reorganization of rasiRNA accumulation. At early stages, gall-distinctive rasiRNAs preferentially accumulated in pericentromeric retrotransposon-rich regions, whereas, at mid-to-late stages, they predominantly localized to chromosome arms, matching DNA transposons, promoters, and gene bodies. A decline in the regulatory influence of miRNAs was observed as infection progressed, possibly reflecting a transition toward specialized regulatory states associated with gall maintenance. Moreover, three regulatory modules, miR2111-5p/HOLT, miR172/AP2, and miR156/SPL10, were tightly but oppositely regulated at 3 and 14 days post-infection. Furthermore, miR156/SPL10 showed crucial functions during gall formation and/or maintenance, possibly influenced by hormonal cues involving ARF8 among other ARFs. Our results highlight stage-specific patterns involving sRNA dynamics, DNA methylation, and transcriptomic changes underlying nematode feeding site development and maintenance. Full article

Cadmium (Cd) is a persistent environmental pollutant that poses a significant health risk to humans and animals, with acute exposure known to induce kidney injury. Fucoidan (Fc), a natural bioactive polysaccharide derived from brown algae, exhibits diverse biological activities; however, its potential to protect against Cd-induced kidney damage and the underlying mechanisms remain unclear. In this study, we investigated the effects of Fc on Cd-induced renal injury in vitro and further explored the role of transcription factor EB (TFEB) in regulating autophagy in its protective mechanism. Our results demonstrate that in Cd-exposed porcine kidney cells (PK-15), Fc suppressed the expression of renal inflammatory factors (TNF-α, IL-1β) and kidney injury markers (NGAL, NTN-1, KIM-1), reduced reactive oxygen species (ROS) production, and downregulated apoptosis-related proteins (cleaved caspase-3 and cleaved caspase-9). Mechanistically, Fc upregulated TFEB protein expression, enhanced the levels of lysosomal function-related proteins (Cathepsin B, CTSB; Cathepsin D, CTSD), and reversed Cd-induced autophagic flux blockade. Importantly, TFEB silencing abolished the protective effects of Fc. Collectively, these findings suggest that Fc exerts renoprotective effects against Cd-induced injury by restoring autophagic flux, a process that involves TFEB. Full article

Henosepilachna vigintioctopunctata is a major pest of solanaceous crops. Matrix metalloproteinase 2 (MMP2) is a zinc ion-dependent endopeptidase that plays a crucial role in the remodeling process of the extracellular matrix (ECM) within cells. However, the function of HvMMP2 in H. vigintioctopunctata remains unknown. In this study, we cloned and characterized the HvMMP2 gene in H. vigintioctopunctata and investigated its function using RNA interference (RNAi). HvMMP2 exists as two transcript variants that differ at the 5′ end. HvMMP2 is highly expressed in the prepupal stage, the pupal stage and the intestine. Silencing HvMMP2 expression in fourth-instar larvae led to approximately 54% mortality at the prepupal stage, with the remaining larvae dying after pupation. RNAi with HvMMP2 in third-instar larvae did not affect their development to the fourth instar, but caused mortality in the majority of larvae during the prepupal and pupal stages, and most of these pupae exhibited wing deformities. Examination of these stunted larvae by dissection showed that their fat bodies were abnormally shaped and that yellow uric acid crystals had accumulated in the Malpighian tubules. Collectively, our findings indicate that HvMMP2 plays a critical role in pupation and eclosion in H. vigintioctopunctata and support HvMMP2 as a potential molecular target for further RNAi-based control studies. Full article

Human endogenous retroviruses (HERVs) are potential driving forces of the pathophysiology of Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), linking post-infectious immune dysfunction to chronic inflammation and immune and neurocognitive dysfunction that are hallmark features of ME/CFS. Accumulating evidence from related autoimmune diseases and cancers has shown that reactivated HERVs can contribute to disease pathogenesis by amplifying immune activation through viral protein-mediated innate sensing, long terminal repeat (LTR)-driven transcription, and disrupting epigenetic silencing. HERV signatures are therefore promising biomarkers for diagnosis, patient stratification for drug-repurposing trials, and therapy monitoring. Accumulating evidence suggests a possible correlation between HERV expression and ME/CFS symptom severity, alterations in immune phenotypes, function and inflammatory gene networks. Importantly, locus-specific HERV profiling is a promising approach for distinguishing ME/CFS from overlapping or co-morbid conditions and healthy controls. Furthermore, HERV-targeted antibodies, immune modulators, epigenetic and antiviral interventions offer promise as concomitant therapeutic strategies for ME/CFS. Additional research incorporating viromics and other-omics validation, functional assays, and HERV-stratified clinical trials is now needed to realise this potential and to transform ME/CFS from a symptom-based syndrome into a mechanism-driven, treatable condition. Full article

The flower color of Rhododendron is primarily determined by anthocyanin biosynthesis, with cytochrome P450 CYP75 family members, particularly flavonoid 3′,5′-hydroxylase (F3′5′H), playing a central role. However, the composition and functional characterization of CYP75 genes in Rhododendron remain insufficiently explored. This study performed genome-wide identification of the CYP75 gene family using the Rhododendron simsii reference genome and functionally characterized the corresponding F3′5′H homolog cloned from Rhododendron × hybridum petals (red cultivar and pink cultivar). Seven RsCYP75 genes were identified, categorized into two subfamilies: RsCYP75A (A1–A5) and RsCYP75B (B1–B2), with a prominent cluster on chromosome 13. All encoded proteins contained a conserved cytochrome P450 domain and typical heme-binding motifs. Among these, RhCYP75A2 showed the highest expression level in red petals at full blooming period and was designated as RhF3′5′H. RhF3′5′H encodes a basic membrane protein with the characteristic F3′5′H motif, with its transcript most abundant in flowers. Transient overexpression of RhF3′5′H in red R. × hybridum petals resulted in a 9.74-fold increase in its transcript levels and a 1.25-fold increase in anthocyanin content compared to that in the control accompanied by the up-regulation of CHS, F3H, DFR and ANS. Conversely, RhF3′5′H silencing reduced anthocyanin accumulation but increased CHS and F3H transcript levels, suggesting a compensatory transcriptional response in the upstream anthocyanin pathway. Moreover, RhF3′5′H was heterologously expressed in E. coli Rosetta as an MBP fusion protein, purified, and identified by LC-MS/MS and ELISA. The protein showed the ability to promote anthocyanin accumulation. Molecular docking analysis demonstrated that RhF3′5′H can bind to naringenin and dihydrokaempferol. These results confirm that RhF3′5′H is a functional F3′5′H-type CYP75A enzyme and a positive regulator of anthocyanin accumulation in Rhododendron petals. This work enriches the CYP75 gene catalog in Rhododendron and provides candidate genes for future studies on flower color regulation and molecular breeding. Full article

(1) Background: Nitric oxide (NO) serves as a crucial signaling molecule in plant abiotic stress responses. Although its role in enhancing drought resistance in cotton has been recognized, the specific mechanisms underlying this physiological and molecular regulation remain largely unexplored. This study aims to elucidate the multi-layered mechanisms by which NO modulates drought resistance in cotton; (2) Methods: Cotton seedlings were subjected to drought stress with the application of the NO donor sodium nitroprusside (SNP). A combination of confocal laser scanning microscopy, transcriptional expression analysis, biochemical assay of enzyme activity, virus-induced gene silencing (VIGS), and in vitro protein modification assays was applied to characterize the effects of NO on the drought stress response in cotton; (3) Results: Exogenous NO significantly reinforced drought resistance in cotton seedlings by improving leaf water retention capacity and photosynthetic efficiency, eliminating excessive drought-induced reactive oxygen species (ROS), upregulating the transcription and enzymatic activity of antioxidant enzymes, and promoting stomatal closure. Mechanistically, NO triggered S-nitrosylation of the plasma membrane H⁺-ATPase isoform GhHA2, thereby enhancing its protein stability; (4) Conclusions: These findings reveal that exogenous NO orchestrates cotton drought tolerance via multiple interconnected physiological and molecular pathways, in which the activation of the antioxidant defense system and the modulation of stomatal closure serve as central regulatory mechanisms. Full article