Search Results (1,467)

Reactive oxygen species (ROS) are integral components of plant signaling networks that mediate interactions between plants and their environment, thereby regulating diverse physiological and biochemical processes. While controlled ROS production is essential for stress perception and signal transduction, excessive ROS accumulation induces oxidative damage. ROS-mediated lipid peroxidation of polyunsaturated fatty acids leads to the formation of highly electrophilic α,β-unsaturated carbonyl compounds collectively referred to as reactive carbonyl species (RCS). Under severe abiotic stress conditions, excessive RCS accumulation exerts cytotoxic effects and causes widespread cellular dysfunction. In contrast, at subtoxic levels, RCS function as important secondary messengers that modulate stress-responsive signaling pathways, including programmed cell death, stomatal regulation, and adaptive responses to abiotic stresses. This review critically synthesizes current advances in understanding the dual roles of ROS and RCS as both damaging agents and signaling molecules in plants. Particular emphasis is placed on the mechanistic basis of ROS-RCS crosstalk and their interactions in abiotic stress tolerance. Furthermore, this review highlights emerging research gaps and outlines future perspectives aimed at translating redox signaling insights into strategies for improving plant stress resilience under changing environmental conditions. Full article

Chemotaxis enables eukaryotic cells to detect and migrate along extracellular chemoattractant gradients spanning several orders of magnitude. This remarkable dynamic range relies on adaptation, a process that allows cells to reset their signaling machinery while preserving sensitivity to incremental changes in stimulus intensity. Although numerous actin-dependent feedback mechanisms have been characterized, the molecular basis of adaptation within an actin-independent core gradient-sensing module remains poorly understood. Here, we identify the Ras GTPase-activating protein, C2GAP1, as a critical F-actin-independent effector of the heterotrimeric G protein, Gα2, in Dictyostelium discoideum. Using cytoskeleton-free gradient-sensing cells, quantitative imaging, biochemical assays, FRET-based G-protein activation measurements, and structural modeling, we demonstrate that C2GAP1 controls concentration-dependent adaptation during gradient sensing. Mechanistically, C2GAP1 directly associates with Gα2 in both GDP- and GTP-bound states, with preferential binding to activated Gα2, thereby sustaining membrane recruitment and locally attenuating Ras and downstream signaling. Loss of C2GAP1 enhances G-protein activation, disrupts local inhibition, and impairs rapid reorientation in dynamic gradients. These findings define a direct coupling between heterotrimeric G proteins and the RasGAP, C2GAP1, as a core adaptive module that enables gradient sensing across a wide concentration range. Full article

GDSL esterase/lipase (GELP) proteins constitute an evolutionarily conserved yet functionally diversified hydrolase family in land plants. They participate in cuticle and secondary cell wall biosynthesis, seed lipid remobilization, reproductive development, and hormone-mediated responses to biotic and abiotic stresses. Despite extensive genome-wide and comparative genomic studies that have categorized large GELPs across numerous crops and model species, only a fraction of members have been functionally characterized in plants, and their catalytic mechanisms and regulatory architectures remain poorly understood. Recent population genomics and cross-species orthogroup analyses in 46 angiosperms have uncovered substantial natural variation within GELP coding sequences and regulatory regions, providing a powerful framework to link allelic diversity to evolutionary trajectories and physiological functions. This review synthesizes current knowledge on GELP evolution, biochemical properties, and roles in development and stress adaptation, and critically evaluates how these insights can be translated into biotechnology and molecular breeding strategies. It highlights emerging resources and concepts from orthogroup-based classification and multi-species datasets that enable systematic discovery of GELP alleles affecting agronomic traits. It further outlines research exploiting GELPs in crop improvement, emphasizing the integration of reverse and forward genetics with multi-omics profiling, biochemical and structural characterization, and gene regulatory network reconstruction. Systematic assessment of the phenotypic impacts of single and combinatorial GELP perturbations on yield, quality, and stress resilience is proposed as a key step toward translating basic insights into breeding and engineering strategies. Full article

Background/Objectives: The rapid emergence of antimicrobial resistance (AMR) is driven not only by antibiotic selective pressure but also by bacterial adaptive responses that enhance genetic diversification under stress. The SOS response, regulated by the RecA-LexA axis, plays a central role in coordinating DNA repair, mutagenesis, and phenotypic adaptation. Targeting this pathway represents a promising strategy to limit bacterial adaptability without directly affecting viability. This study aimed to evaluate benzoxaborole-based compounds as potential inhibitors of the LexA regulatory pathway. Methods: A drug repurposing approach was employed to investigate the benzoxaborole scaffold and the clinically approved derivatives tavaborole and crisaborole. Biochemical assays were used to assess LexA autocleavage in a RecA-dependent co-protease system. Molecular docking analyses were performed to evaluate compound binding within the LexA catalytic site. Microbiological assays were conducted to examine the effects on antibiotic-induced filamentation and biofilm formation under different growth conditions. Results: Selected benzoxaboroles inhibited LexA autocleavage, with tavaborole showing the strongest inhibitory profile in the biochemical assay. Docking analyses supported these findings, indicating stable binding within the LexA catalytic site near the catalytic serine residue. At the cellular level, tavaborole and benzoxaborole significantly reduced levofloxacin-induced filamentation at sub-inhibitory concentrations. Both compounds also decreased biofilm formation under nutrient-limited conditions, while no significant effects were observed on preformed biofilms. Crisaborole showed limited cellular activity despite measurable biochemical effects. Conclusions: These findings identify benzoxaboroles as modulators of the LexA-dependent SOS response and support the potential repurposing of clinically approved compounds as adjuvants to limit bacterial adaptive responses associated with antimicrobial resistance. Full article

Fermented dairy products with probiotic and functional properties are a promising matrix for modulation of the human microbiome. The functionality of such products will depend not only on the technological properties of the lactic acid bacteria included in the starter culture but also on the combined effects of metabolites, enzymatic activity, stress tolerance, and strain-specific adaptation mechanisms. The aim of this work was to conduct a comprehensive analysis of Lactobacillus strains to facilitate the design of microbial consortia for the development of fermented products with diverse functional properties. Twenty Lactobacillus strains from different species were investigated using microbiological, physicochemical, and biochemical methods to evaluate antagonistic activity against opportunistic microorganisms and to assess changes in amino acid and organic acid profiles, vitamin content, fatty acid composition, and enzymatic activity. Additionally, proteomic analysis was performed to create a matrix of functional complementarity of the studied strains, representing proteins associated with antimicrobial activity, bacteriocin transport, resistance to oxidative stress, surface structure formation, and adhesion. It was shown that the studied strains exhibit pronounced functional heterogeneity, demonstrating the feasibility of scientifically based selection of strains to create next-generation fermented dairy products with predictable properties. Full article

Proteomic research in the genus Vitis has progressed from early biochemical studies of soluble proteins to high-resolution, quantitative analyses encompassing all major organs and derived products. This review provides a comprehensive synthesis of advances in grapevine and wine proteomics. In leaves, studies have revealed extensive remodeling of photosynthetic, antioxidant, and defense pathways under biotic (e.g., Plasmopara viticola, Erysiphe necator, Xylella fastidiosa, Candidatus Phytoplasma vitis) and abiotic stresses (drought, salinity, heat, light). Bud proteomics elucidated hormonal regulation and mechanisms of dormancy release, while root studies identified nitrate-dependent metabolic shifts and adaptive protein networks. Cell culture models enabled controlled investigation of elicitor responses, stilbene biosynthesis, and temperature-induced proteome changes. In berries, proteomics clarified developmental transitions from fruit set to ripening, emphasizing proteins related to secondary metabolism, vacuolar transport, and stress tolerance. Comparative analyses across cultivars and environments identified biomarkers linked to aroma, color, and texture. The wine proteome revealed selective persistence of grape-derived proteins (e.g., thaumatin-like proteins, chitinases) and yeast peptides influencing stability and sensory properties, while Botrytis cinerea infection significantly alters this balance by degrading PR proteins and introducing fungal enzymes. Altogether, the Vitis proteome emerges as a dynamic, multifunctional system crucial for understanding plant adaptation, enological quality, and biomarker discovery. Full article

Seasonal drought constitutes a major abiotic stress limiting the growth and yield of pineapple, a globally important Crassulacean acid metabolism (CAM) crop. The sucrose catabolism mediated by cell wall invertase (CWIN) plays a vital role in regulating plant growth and development, as well as adaptive responses to abiotic stresses. Invertase inhibitors (INHs) serve as specific post-translational regulators that modulate CWIN enzymatic activity. However, the INH family has not been systematically characterized in pineapple, and its functional roles in mediating sucrose metabolism and drought resistance remain elusive. In this study, three AcINHs were identified from the pineapple genome, followed by comprehensive analyses of their gene structures, phylogenetic relationships, homology characteristics and protein structures. Structural analysis revealed that all AcINH members harbor conserved motifs 1, 2, 3, 5 and 9, whereas only AcINH3 possesses motif 7. Expression analysis showed that only AcINH3 was significantly transcriptionally induced by drought stress among all family members. Functional validation demonstrated that AcINH3 knockout markedly elevated CWIN activity in pineapple seedling leaves, facilitating hexose accumulation and promoting plant growth and development. Moreover, AcINH3-edited lines exhibited enhanced drought resistance, accompanied by increased accumulation of soluble sugars (sucrose, glucose, fructose), abscisic acid (ABA), and proline (PRO), reduced malondialdehyde (MDA) content, and enhanced peroxidase (POD) activity. Biochemical assays further verified a direct physical interaction between AcINH3 and AcCWIN1, which mediates sucrose metabolism and drought stress responses. Collectively, this study identifies a novel AcINH3–AcCWIN1 post-translational module that modulates sugar metabolism and drought tolerance in pineapple, providing critical mechanistic insights for CAM plants. Our findings highlight AcINH3 as a promising target for genome-editing breeding to enhance drought resistance in CAM crops. Full article

The biochemical diversity among tea plant (Camellia sinensis) cultivars serves as the core material basis associated with tea quality and is of great significance for the innovation of tea germplasm resources and the genetic improvement of tea varieties. Here, we systematically analyzed 16 biochemical components, 7 mineral elements, and water-soluble fluoride (WSF) in 65 tea cultivars using multivariate analysis. These cultivars were grouped into high-component, high-epigallocatechin (EGC), low-component, and balanced-quality clusters. Significant variation was observed in quality-related parameters, including tea polyphenols, catechins, and amino acids and related quality indices. Mineral elements were significantly correlated with quality components, with potassium and boron showing significant correlation with the accumulation of these components. WSF content exhibited a pronounced cultivar-dependent variation, with more than 72% of cultivars containing less than 100 mg·kg⁻¹. The balanced-quality cluster exhibited broad processing adaptability, making it suitable for producing various tea types. The high-EGC cluster is ideal for developing specialty functional teas. The high-component cluster offers core parental material for breeding cultivars high in tea polyphenols and epigallocatechin gallate. This study provides a scientific basis for the screening and utilization of tea germplasm resources and the development of new, high-quality, and safe tea varieties. Full article

Neuroblastoma is characterized by noticeable resistance to chemotherapy, largely driven by the ability of tumour cells to reorganize stress-adaptive signalling networks rather than relying on single oncogenic drivers. We conducted a study to investigate the pharmacological mode of action of doxorubicin in modifying adaptive signalling pathways in SH-SY5Y neuroblastoma cells, and whether the capacity of plant metabolites can exploit emergent biochemical vulnerabilities. Transcriptomic profiling through RNA sequencing conducted 48 h post-doxorubicin exposure unveiled the organized disruption of pathways linked with amyloidogenic processes, oncogenic signalling pathways, oxidative stress, and DNA repair. The protein–protein interactions, coupled with Kyoto Encyclopedia of Genes and Genomes pathway evaluations, revealed five network-central-hubs: BRAF, GSK3β, PARP1, BACE1, and MAOB. Structural docking integrated with 200 ns molecular dynamics simulations illustrated binding stability across multiple targets driven by three metabolites, Lactol binding to BRAF (−54.13 kcal/mol) and MAOB (−39.08 kcal/mol), Amino(1H-indol-2-yl)acetic acid to BACE1 (−41.07 kcal/mol) and GSK3β (−47.38 kcal/mol), and Quercetin-3-(6″-malonyl-glucoside) binding to PARP1 (−46.03 kcal/mol). In vitro Cell Counting Kit-8 proliferation assays validated the significant anti-neuroblastoma efficacy, with the lowest IC₅₀ (0.2397 µM) being exhibited by Amino(1H-indol-2-yl)acetic acid, followed by Lactol (1.226 µM) and Quercetin-3-(6″-malonyl-glucoside) (1.301 µM), which mirrored the cytotoxic action of doxorubicin (1.306 µM). These results suggest that plant-derived metabolites may interact with stress-adaptive signalling pathways connected with neuroblastoma. However, direct experimental validation of target engagement and pathway modulation will be required to confirm these predicted interactions. Full article

Laryngeal squamous cell carcinoma (LSCC) remains a major clinical challenge within head and neck oncology, with five-year survival rates showing minimal improvement over recent decades despite advances in surgical and multimodal therapeutic strategies. Increasing evidence identifies metabolic reprogramming as a central driver of tumor progression, therapeutic resistance, and immune evasion in LSCC. Beyond the classical Warburg effect, LSCC exhibits profound metabolic reprogramming, involving coordinated alterations in carbohydrate, amino acid, lipid, and iron metabolism that support adaptation to hypoxic and nutrient-deprived microenvironments. Hypoxia-inducible factors, particularly HIF-1α, coordinate these key biochemical pathways and enzymatic steps by integrating glycolysis, glutaminolysis, folate-dependent one-carbon pathways, lipid synthesis, and mitochondrial remodeling, while also influencing stromal and immune components of the tumor microenvironment. Metabolic crosstalk between tumor cells, cancer-associated fibroblasts, and immune populations promotes immunosuppression through nutrient competition and accumulation of metabolites such as lactate and lipid-derived mediators. In parallel, dysregulated iron handling and altered ferroptosis susceptibility emerge as key determinants of tumor aggressiveness and treatment response. This review synthesizes current evidence on metabolic rewiring in laryngeal squamous cell carcinoma, highlighting how alterations in metabolic pathways create targetable vulnerabilities that drive tumor biology, immune modulation, and resistance to conventional and emerging therapies. Elucidating these metabolic dependencies may support the development of metabolism-based biomarkers and therapeutic strategies in laryngeal squamous cell carcinoma, providing an integrated and translational perspective that links tumor metabolism with microenvironmental interactions and immune modulation, while highlights emerging therapeutic vulnerabilities. Full article

Chronic diseases increasingly reflect a shared biological origin: persistent cellular stress. This review summarizes the biochemical mechanisms that normally preserve cellular homeostasis, namely redox regulation, endoplasmic reticulum proteostasis, mitochondrial quality control, autophagy, and DNA damage response, and explains how they fail under sustained lifestyle-related overload. Repeated exposure to psychological stress, sleep disruption, hypercaloric intake, and physical inactivity shifts adaptive signaling toward maladaptation, promoting oxidative damage, protein misfolding, mitochondrial dysfunction, low-grade inflammation, and genomic instability. These interconnected processes contribute to the development and progression of major chronic non-communicable diseases, including obesity, type 2 diabetes, cardiovascular disease, neurodegeneration, and cancer. Particular emphasis is placed on circadian and neuroendocrine regulation, especially overactivation of the hypothalamic–pituitary–adrenal axis and impaired nocturnal regenerative pathways such as glymphatic clearance and DNA repair. Together, the evidence supports a unifying model in which chronic pathology emerges from cumulative failure of cellular resilience systems rather than isolated organ-specific defects. This perspective highlights sleep optimization, stress reduction, and metabolic regulation as mechanistically grounded strategies for prevention and supportive interventions for chronic disease. Full article

Psychrophilic organisms are able to grow at temperatures down to −15 °C, while hyperthermophiles can multiply at temperatures up to 122 °C. What structural changes in extremophile proteins are needed to maintain stable and biochemically active structures under such conditions? Understanding how such extremophiles accomplish this is relevant for human health, biotechnology, and our search for life elsewhere in the universe. The purpose of the current study is to report and compare the structures of four rubredoxins (Rds), the first ever two experimental psychrophile bacteria structures (from Gram-positive Clostridium psychrophilum and Gram-negative Polaromonas glacialis) and two hyperthermophiles from the Gram-negative Thermotoga maritima bacterium and the archaeon Pyrococcus yayanosii, also a piezophile, as part of a program to understand structural variations that support both stability and function under extreme conditions. These structures were obtained using synchrotron radiation X-ray diffraction at 100 K. All four structures had the expected overall rubredoxin fold. Rubredoxin from the only aerobic psychrophilic bacterium Polaromonas glacialis had larger variations in sequence and structure, whereas the other psychrophilic bacterium showed properties closely related to hyperthermophile rubredoxins. Multi-subunit structures showed similar RMSD variability independent from their thermal adaptation status. We propose including functional information in the analysis since temperature optimization may not be the only determinant for a specific protein adaptation. Full article

Background: Exclusive enteral nutrition (EEN) is the recommended first-line therapy for induction of remission in pediatric mild-to-moderate Crohn’s disease (CD), but its restrictive nature often limits adherence and long-term sustainability. A modified version of the Crohn’s Disease Exclusion Diet (CDED), integrating Mediterranean dietary principles, was developed to offer a more acceptable alternative while preserving therapeutic efficacy. Methods: We conducted a retrospective, single-center study comparing short- and long-term outcomes of a Mediterranean-adapted CDED (M-CDED) with partial enteral nutrition (PEN) versus standard EEN in children with mild-to-moderate CD. Clinical remission was assessed after 8 and 16 weeks, while long-term outcomes were assessed after 1 and 2 years. Results: Data collected from thirty-two patients were analyzed (EEN, 14; M-CDED, 18). Clinical remission rates were comparable after 8 weeks (92.8% EEN vs. 94.4% M-CDED) and 16 weeks (100% in both groups). However, at 12 and 24 months, M-CDED was associated with significantly higher rates of clinical and biochemical remission and a markedly lower need for biologic drugs (12-month biologic initiation: 50% EEN vs. 11.1% M-CDED; p = 0.01). Adherence to M-CDED was excellent throughout follow-up. Conclusions: M-CDED with PEN appears to be as effective as EEN for remission induction, with improved long-term disease control and reduced therapeutic escalation. These findings support the feasibility of M-CDED as a sustainable option for long-term management of pediatric CD. Prospective studies are needed to confirm these results. Full article

Botanical extracts have emerged as promising biostimulants in agricultural systems because of their ability to modulate key metabolic and redox processes in crops, thereby increasing stress tolerance and productivity. This review synthesizes current knowledge on how botanical extracts influence plant metabolism and redox homeostasis, with a particular emphasis on their role in adaptive cellular responses. Evidence indicates that these extracts can increase antioxidant enzyme activity, regulate reactive oxygen species (ROS) signaling, and promote the accumulation of bioactive metabolites associated with improved stress tolerance and enhanced growth. This review also examines how agronomic practices, including nutritional management, water availability, light regimes, and preharvest biostimulant applications, together with emerging biotechnological approaches, can be strategically employed to optimize the bioactive composition and efficacy of botanical extracts. By integrating recent advances in metabolomics and transcriptomics, the manuscript highlights the biochemical and molecular reprogramming triggered by botanical extracts. It identifies key challenges, including variability in extract composition, lack of standardization, and context-dependent responses. Finally, future research directions are outlined, emphasizing the need for mechanistic understanding, quantitative evaluation of plant responses, and the development of standardized frameworks to support the sustainable application of botanical extracts in agriculture. Full article

Highland barley (Hordeum vulgare var. nudum), a member of the genus Hordeum in the family Poaceae, represents a unique cultivated crop adapted to the Qinghai–Tibet Plateau. Weed infestation has long posed a serious threat to the yield and quality of highland barley, and the lack of effective weed management strategies has become a major constraint in its production. Pyroxsulam is an acetolactate synthase (ALS)-inhibiting herbicide widely used for weed control in highland barley fields. This study investigated the molecular mechanisms underlying the response of highland barley to pyroxsulam by integrating physiological, biochemical, and transcriptomic analyses. ALS activity assays showed that the resistant variety ‘Qing0306’ exhibited a significant increase in relative ALS activity within 1–4 days after pyroxsulam treatment. qRT-PCR analysis revealed a rapid induction of HvnALS expression, which was significantly higher in ‘Qing0306’ than in ‘Qing0160’ on the first day after treatment (p < 0.01), indicating that resistance is primarily associated with target-enzyme overexpression rather than target-site mutations. Moreover, transgenic Arabidopsis lines overexpressing HvnP450 and HvnGSTs displayed enhanced tolerance to pyroxsulam, as evidenced by an increased root length and fresh weight compared with wild-type plants. This study provides mechanistic insights that support the genetic improvement of pyroxsulam-resistant highland barley. Full article