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PubMed2026

Investigating telomere length and hTERT-MNS16A VNTR polymorphism in Bipolar disorder: Insights into clinical features.

OBJECTIVE: To compare leukocyte telomere length (LTL; T/S ratio) and hTERT-MNS16A VNTR polymorphism between patients with bipolar disorder (BD) and healthy controls, and to examine their associations with clinical features in BD. METHODS: A total of 179 participants (100 BD patients, 79 healthy controls) were enrolled. Relative LTL was assessed by qPCR-based T/S ratio; hTERT-MNS16A VNTR genotyping by PCR and gel electrophoresis. Clinical variables including episode frequency, illness duration, age at onset, symptom severity scales, first episode polarity, and family history of mood disorder were evaluated. RESULTS: No significant differences were observed between BD patients and healthy controls in T/S ratio or hTERT-MNS16A VNTR genotype distributions (all p > 0.05). Within the BD group, S allele carriers (L/S or S/S) had significantly more depressive episodes than L/L homozygotes (1.45 ± 2.58 vs. 0.61 ± 1.52; p = .040). Significant inverse correlations were identified between T/S ratio and depressive episode count (ρ = -0.220, p = .028) and total mood episodes (ρ = -0.207, p = .039). Multivariable negative binomial regression revealed four independent predictors of depressive episode frequency: lower T/S ratio (p = 0.005), S allele carriage (L/S or S/S genotypes) (p = 0.001), first depressive episode polarity (p < 0.001), and family history of mood disorder (p = 0.035). CONCLUSION: Although LTL and hTERT-MNS16A VNTR genotype did not differ between BD patients and healthy controls, shorter telomere length and S allele carriage were independently associated with higher depressive episode frequency within the BD group, implicating telomere biology and hTERT genetic variation in the biological substrate of depressive illness burden.

Humans↗

PubMed2026

Lipid-mediated activation of BLT2 promotes membrane repair to prevent cell death.

Various pathogenic microorganisms produce toxins that create pores in cell membranes, causing cell damage and disrupting the host epithelial barrier. Recently, we reported that mice lacking the G protein-coupled receptor leukotriene B4 receptor 2 (BLT2), which is expressed in vascular endothelial and alveolar epithelial cells, are highly susceptible to pneumolysin (PLY), a pneumococci-generated toxin. Although we clarified the protective roles of BLT2 in vascular endothelial cells, those in alveolar epithelial cells have not been elucidated. Here, we report that lipid mediator 12-hydroxyheptadecatrienoic acid (12-HHT), which is produced by membrane-damaged epithelial cells, prevents cell death by promoting membrane repair through BLT2. BLT2 promoted the release of PLY-bound plasma membranes as extracellular vesicles in a sphingomyelinase-dependent manner. Additionally, BLT2 activated Rac1 and subsequent actin polymerization, leading to resistance to cell death. Furthermore, inhibition of 12-HHT production by aspirin and treatment with a BLT2 antagonist abolished the protective effect of BLT2. These findings provide a new therapeutic strategy for bacterial infection.

Receptors, Leukotriene B4↗

PubMed2026

Activity shapes large herbivores' ecological influences.

The ecological effects of large herbivores are shaped by their spatial and temporal patterns of activity (i.e. where, when and how intensely they use specific locations). When large herbivores' ecological influences are perceived to be undesirable, the traditional approach has been to reduce their population size. This numbers-first logic assumes that ecological effects scale primarily with abundance. We argue that this framing provides an incomplete understanding of large herbivores' ecological impacts. Using African elephants (Loxodonta africana) as a well-documented case study, we show that ecological effects on plants, animals and ecosystem processes correlate more with spatio-temporal patterns of activity than with population size. In large, open systems characterized by strong gradients of water availability, forage quality, shade and risk, elephants concentrate into predictable hotspots while relaxing activity elsewhere, generating localized impacts and opportunities for recovery. By contrast, in small, fenced or fragmented landscapes, where movements are constrained, and gradients are weak, spatial self-regulation breaks down, producing homogenized use and widespread ecological effects. We contend that understanding where, when and under what constraints herbivores use space provides a more general and mechanistic basis for interpreting ecological influence than abundance alone, with implications that extend beyond elephants to large herbivores globally.

Animals↗

PubMed2026

Genome-Wide Impact of Human DBR1 Depletion on RNA Processing Networks Reveal a Connection Between Pre-mRNA Splicing, mRNA Surveillance and Stress Granule Dynamics.

The RNA lariat debranching enzyme DBR1 is essential for intron turnover and RNA metabolism, yet its broader impact on transcriptome regulation remains incompletely defined. To elucidate the consequences of DBR1 depletion, we performed transcriptome-wide RNA sequencing of DBR1-knockdown and wild-type HEK293 cells. Differential expression analysis revealed widespread perturbations in pathways linked to RNA splicing, mRNA surveillance, translational control, and stress-granule biology. Many of the most significantly altered transcripts encode splicing factors and RNA quality-control components, underscoring DBR1's influence on post-transcriptional regulation. Alternative splicing analysis showed changes across multiple event types, with exon skipping accounting for >50% of events, followed by mutually exclusive exons, alternative 5' and 3' splice sites, and retained introns, indicating that DBR1 depletion induces pervasive splicing defects. Direct spliceosome inhibition using isoginkgetin (blocks tri-snRNP recruitment) and pladienolide B (targets SF3B1) reproduced the DBR1-KD mis-splicing patterns of cell signaling genes and factors involved in RNA metabolism, supporting a functional link between DBR1 activity and alternative splicing. Notably, DBR1 knockdown revealed a subset of transcripts that are both NMD-sensitive and enriched within stress granules. Consistent with this observation, G3BP1 immunopurification and confocal microscopy further support a role for DBR1 and UPF1 in stress-granule dynamics, suggesting that these factors may participate at distinct stages to influence mRNA fate under stress conditions. Together, these findings indicate that DBR1 functions beyond lariat RNA turnover as a common regulator of RNA processing, transcriptome stability, and stress granule homeostasis, revealing intricate crosstalk between RNA splicing and RNA quality control pathways in human cells.

Humans↗

PubMed2026

Targeted sequencing reveals a distinct genetic alteration landscape in oral multiple primary squamous cell carcinomas.

OBJECTIVE: Oral multiple primary cancers (MPCs) are associated with poor clinical outcomes, yet their genomic characteristics remain insufficiently understood. DESIGN: Fifty-four formalin-fixed paraffin-embedded (FFPE) tumor samples from 30 patients with oral MPCs were analyzed using high-depth targeted sequencing of a customized 14-gene panel derived from prior whole-exome sequencing data. Detected alterations were analyzed after removal of synonymous mutations. RESULTS: Non-silent genomic alterations were identified in 59.3% (32/54) of samples, involving 19 patients. A total of 70 variant loci across 13 genes were detected. AKAP13 was the most frequently mutated gene at both the sample (22.2%, 12/54), with recurrent mutations observed across multiple patients. In contrast, TP53 mutations occurred at a substantially lower frequency (11.1%, 6/54). Marked inter- and intra-patient mutational heterogeneity was observed. CONCLUSIONS: FFPE-based targeted sequencing enabled an initial characterization of genomic alterations in oral MPCs. Recurrent alterations in AKAP13, GLI2, JMJD1C, and DNAH8, together with the relatively low frequency of TP53 alterations, identify candidate genomic features for further investigation and provide a basis for future studies of the molecular basis of oral MPCs.

Humans↗

PubMed2026

Functional characterization of the MdFLZ2 gene in drought and salt stress tolerance in apple.

Drought and salt stress are significant environmental limitations that severely constrain plant growth and productivity, therefore, enhancing stress tolerance is a key goal in crop improvement. The plant-specific FCS-like zinc finger (FLZ) proteins have been identified as important regulators of stress adaptation. In this study, we conducted a genome-wide characterization of the FLZ gene family in apple and functionally characterized MdFLZ2. qRT-PCR analysis revealed that MdFLZ2 was differentially expressed across various tissues and transcriptionally induced by both drought and salt stress. Subcellular localization assays demonstrated that the MdFLZ2 protein is localized to both the nucleus and the cytoplasm. The overexpression of MdFLZ2 in apple calli, Arabidopsis and tomato conferred increased resistance to drought and salt stress. In addition, yeast two-hybrid (Y2H) assays confirmed that MdFLZ2 interacted with MdSnRK1.1, and similar interactions were also detected between other MdFLZ family members and MdSnRK1.1. Collectively, our findings suggest MdFLZ2 as a positive regulator of drought and salt tolerance and highlight its potential to serve as a genetic resource for abiotic stress improvement.

Malus↗

PubMed2026

Molecular Determinants and Therapeutic Targeting of Stop Codon Readthrough in Eukaryotic Translation.

Accurate translation termination is essential for proteome integrity and in eukaryotes is primarily governed by the release factors eRF1 and eRF3, which ensure precise recognition of stop codons and efficient release of nascent polypeptides. However, proteome integrity is challenged by mutations that generate premature termination codons (PTCs), leading to truncated, nonfunctional proteins and degradation of the aberrant transcript via nonsense-mediated mRNA decay (NMD). Collectively, these events account for ∼1800 human genetic diseases. Translational readthrough, the process by which near-cognate tRNAs decode stop codons and allow ribosomes to continue elongation beyond the stop codon, represents a possibility to suppress PTCs and restore full-length protein synthesis. Initially discovered in viruses as a mechanism to expand coding capacity, readthrough is now recognized as a regulated feature of eukaryotic gene expression influenced by both cis-acting sequence elements and trans-acting factors. Recent evidence highlights the remarkable context dependence of readthrough, revealing variation across transcripts, tissues, and developmental stages. In this review, we examine the molecular determinants that define stop codon recognition and readthrough efficiency, with particular emphasis on nucleotide context. We further discuss the mechanisms and binding sites of small molecules that promote PTC readthrough, and summarize the clinical development landscape of readthrough-inducing compounds for the treatment of diseases caused by nonsense mutations.

Humans↗

PubMed2026

Comparative genomic and proteomic analysis reveals orthogroup structured evolution of tick protease inhibitors.

Protease inhibitors (PIs) play central roles in regulating endogenous proteolysis and host-parasite interactions in ticks. However, the evolutionary architecture underlying their diversification across tick lineages remains insufficiently resolved. Here, we performed a genome-wide comparative analysis of predicted proteomes from 14 tick species to systematically characterize PI repertoires. In total, 4931 putative PIs were identified and grouped into 20 families using the MEROPS classification system. Further, PI families such as Antistasin, WAP-type, and Pacifastin, which have not previously been systematically reported in tick genomes, were classified. Orthogroup inference demonstrated that PI expansion is structured at the level of evolutionary lineages rather than uniformly across families. By stratifying orthogroups according to duplication burden and taxonomic conservation, we identified a broadly conserved single-copy core under strong purifying selection. Motif level analysis of serpin reactive center loops further revealed conservation of inhibitory specificity within single copy orthogroups and diversification of key functional residues in duplication-associated lineages. Integration of secretion prediction and tissue-resolved proteomics from Hyalomma anatolicum and Rhipicephalus microplus demonstrated that evolutionary stratification is reflected at the protein level. Together, these findings provide an orthogroup-resolved evolutionary framework linking duplication dynamics, molecular evolution, and tissue-level protein deployment. This integrative approach offers a systematic basis for prioritizing conserved and diversified PI lineages for future functional and anti-tick intervention studies.

Animals↗

PubMed2026

In Vitro comparison of herbal and conventional antifungals against Candida strains in Oral candidiasis: A systematic review and meta-analysis.

OBJECTIVE: This study aimed to systematically review and meta-analyze the in vitro antifungal activity of herbal and conventional antifungals against Candida strains. DESIGN: In vitro studies were identified through PubMed, Embase, Scopus, and Web of Science up until May 2026. This review is registered with Prospero (CRD420251128404). Eligibility was determined using the Population, Intervention, Comparison, and Outcome (PICO) framework, with specific inclusion and exclusion criteria focused on in vitro antifungal investigations comparing herbal antifungals with conventional antifungals. The risk of bias was assessed using the modified Quality Assessment Tool for In Vitro Studies (QUIN Tool). A meta-analysis was performed, with the primary outcome measure being the ratio of means (RoM). RESULTS: The systematic review included twenty-five articles. Most studies showed different results in inhibition zones or minimum inhibitory concentrations between herbal and conventional agents. The meta-analysis indicates that certain herbal antifungals are equally effective as or more effective than conventional antifungals against Candida dubliniensis, Candida lusitaniae, and Candida tropicalis. While the efficacy of herbal antifungals for Candida albicans and Candida glabrata was modest, Piper betle L. demonstrated significant inhibitory potential. In contrast, conventional antifungals outperformed herbal antifungals against Candida krusei and Candida parapsilosis. CONCLUSIONS: This systematic review and meta-analysis highlight herbal medicine as a potential antifungal therapy for oral candidiasis, emphasizing the need for new strategies due to resistance to conventional antifungals.

Humans↗

PubMed2026

Influence of nicotine on protein expression around hydrophilic osseointegrated implants: A proteomic study in male rats.

OBJECTIVE: To ensure the success of dental implant treatment, various factors must be considered, including osseointegration and systemic conditions. There is evidence in the literature that smokers may exhibit alterations in tissue healing, which can compromise the success of implant rehabilitation. Therefore, this study aimed to investigate the influence of nicotine on the protein profile of bone tissue around hydrophilic implants during the osseointegration process in rats. DESIGN: Bone tissue samples from the control and nicotine groups (n = 3 per group) were subjected to protein extraction, mass spectrometry, and bioinformatic analyses. Protein identification was performed using Proteome Discoverer 2.1 software and the SEQUEST algorithm, and the protein data were compared with those of a protein database of Rattus norvegicus obtained from UniProt. RESULTS: A total of 740 proteins were detected in both the control group and the nicotine-exposed group. Among them, the proteins biglycan, periostin and histone H4 were highlighted because of their higher abundance in the healthy implant group, while they were reduced in the nicotine-exposed group. CONCLUSIONS: Nicotine has the potential to alter the protein profile of bone tissue around hydrophilic implants during osseointegration, which may impair tissue remodeling and healing.

Animals↗

PubMed2026

Identification of the BrSK gene family in flowering Chinese cabbage and functional characterization of BrSK2 subfamily involvement in heat stress.

Glycogen synthase kinase 3 (GSK3) kinases are evolutionarily conserved regulators of plant development and stress signaling, yet their contributions to thermotolerance in cool-adapted Brassica crops remain poorly understood. Here, we identified 16 BrSK genes in the Caixin (Brassica rapa ssp. chinensis var. parachinensis) genome, all harboring intact catalytic motifs indicative of functional kinase activity. Spatiotemporal expression profiling revealed preferential accumulation of BrSK transcripts in stem apices and floral organs during reproductive transition, while promoter analysis identified abundant heat- and abiotic stress-responsive cis-elements. Under heat stress, BrSK21, BrSK22, and BrSK23 displayed striking genotype-specific expression dynamics. BrSK21/22/23 transcripts were stably suppressed in the heat-tolerant cultivar '49-19' but transiently declined before rapidly rebounding in the heat-sensitive 'Liuye 50', mirroring RNA-seq profiles. Protein-protein interaction assays (Y2H, BiFC, and LCI) demonstrated specific associations between BrSK kinases and BrHSFA1. Functional validation via VIGS revealed that silencing of BrSK21 significantly enhanced thermotolerance, with triple silencing of BrSK21/22/23 conferring additive protection, indicating functional redundancy within the BrSK2 subfamily. Collectively, these findings establish the BrSK2 subfamily as negative regulators of heat tolerance in Caixin, likely via modulation of BrHSFA1 expression. This work identifies high-priority targets for molecular breeding of climate-resilient Brassica vegetables.

Plant Proteins↗

PubMed2026

Genome-wide identification and functional validation of asparagine synthetase genes (NtASNs) in Nicotiana tabacum.

Asparagine (Asn) is pivotal for plant nitrogen (N) metabolism and plays indispensable roles in plant growth, development, and stress tolerance. However, the systematic characteristics and core functions of asparagine synthetase genes (NtASNs) in tobacco remain unclear. Through a comprehensive genome-wide investigation, nine members of the NtASN gene family were identified. Subsequent CRISPR/Cas9-mediated knockout and overexpression assays of these NtASN genes revealed that NtASN1e, NtASN2a, and NtASN2b are the core genes responsible for Asn biosynthesis in tobacco. Their knockout reduced asparagine synthetase activity and Asn content, delayed seed germination by 2-3 days, and displayed elevated oxidative injury when exposed to salinity conditions. In contrast, overexpression of these genes elevated Asn accumulation. Subcellular localization analysis indicated that NtASN1e was localized to both the cytoplasm and chloroplasts, whereas NtASN2a exhibited dual localization in the cytoplasm and endoplasmic reticulum, and NtASN2b was mainly localized in the cytoplasm. This study systematically clarifies the evolutionary characteristics and core functions of the NtASN gene family and provides candidate genes for optimizing nitrogen metabolism and improving salt-stress adaptation in tobacco. These findings hold important practical significance for molecular breeding and product quality improvement in industrial crops.

Nicotiana↗

PubMed2026

The circadian clock proteins PRR modulate root hair development via the RHD6/RSL module in Arabidopsis.

Root hairs, derived from trichoblasts, are critical for plant growth and environmental adaptation. Although environmental cues are known to influence root hair development, how endogenous timing systems such as the circadian clock integrate into the core transcriptional network governing root hair formation remains unclear. Here, we show that the circadian clock-associated protein PSEUDO-RESPONSE REGULATOR5 (PRR5) physically interacts with ROOT HAIR DEFECTIVE6 (RHD6) and RHD6 LIKE1 (RSL1), two basic helix-loop-helix transcription factors essential for root hair initiation. Genetic analyses suggest that PRR proteins contribute to root hair development under long-day conditions in Arabidopsis thaliana. Simultaneous disruption of PRR5, PRR7, and PRR9 results in defective root hairs, whereas PRR5 overexpression markedly increases root hair density and length. Transcriptomic and RT-qPCR analyses reveal that PRRs enhance the expression of RHD6, RSL1, and multiple downstream root hair-responsive genes, while modulating their temporal expression patterns. Furthermore, PRR5-mediated root hair promotion requires RHD6/RSL1, and PRR proteins enhance RHD6-dependent activation of the RSL4 promoter. PRRs also contribute to root hair development under phosphate-deficient and salt-stress conditions. Together, these findings establish a molecular framework in which PRR proteins regulate the RHD6/RSL network to coordinate root hair development and environmental responses.

Arabidopsis↗

PubMed2026

Systematic identification pepper CaE2F transcription factor reveals the role of CaDPb in drought stress response.

The EARLY 2 FACTOR (E2F) transcription factor (TF) family plays a pivotal role in regulating plant development and adaptations to environmental stresses. However, the physiological function of E2Fs in pepper (Capsicum annuum L.) are not well elucidated. In this work, we conduct a comprehensive genome-wide annotation of the E2F family within the Zunla-1 pepper genome and further explore the biological roles of CaDPb in response to drought stress. Through systematic bioinformatics analysis, we identify a total of nine CaE2F genes within the Zunla-1 genome, categorizing them into three distinct subgroups. Additionally, we discover multiple cis-regulatory elements in the CaE2F promoter regions associated with responses to plant hormones and drought stress. Public RNA-seq datasets reveal distinct expression profiles of CaE2F genes across various pepper tissues and their responses to environmental stimuli and plant hormones. Subsequently, the CaDPb gene is further functionally verified in drought response. Our findings indicate that TRV2:CaDPb silenced pepper plants are more sensitivity to drought. Furthermore, we show that CaDPb participates in the regulation of reactive oxygen species (ROS) production, the expression of drought-responsive genes, and the modulation of stomatal aperture. Taken together, our findings provide a comprehensive characterization of E2F genes in pepper and offer insights into the biological function of CaDPb in pepper drought stress response.

Capsicum↗

PubMed2026

Comparative analysis of DDR-related genes and microRNA expression during rice germination: Implications for salinity susceptibility screening.

Soil salinity poses a significant threat to the agri-food sector and particularly to rice cultivation. High salinity during germination induces overproduction of reactive oxygen species (ROS) that cause lesions in the DNA resulting in reduced vigor. MicroRNAs (miRNAs) are known to modulate stress response in plants, however, studies focusing on its relation with the expression of the DNA damage response (DDR)-related genes are not thoroughly explored. In this regard, the aim of this work was to investigate the link between the expression of miRNAs and putative targeted DDR-related genes in response to salinity stress during germination. Eight varieties representative of indica and japonica rice subspecies were categorized into clusters through a principal component analysis (PCA) based on their germination performance and stress tolerance index under varying concentrations of NaCl. Subsequently, the expression patterns of six miRNAs and their putative targeted DDR genes were measured in two contrastive cultivars through quantitative real-time PCR (qRT-PCR) while correlations were examined through Pearson's analysis. Results showed distinct expression profiles between halotolerant and sensitive cultivars. Two miRNAs were further investigated in mature dry seeds of all the cultivars to verify their earliest, seed-specific discriminative potential. The distinct miR414 expression pattern may represent a potential biomarker for identifying salinity-susceptible cultivars during early-stage breeding screening.

Oryza↗

PubMed2026

Biochemical Insights Into the Conserved Interactions of NMD Factors From Budding Yeast to Humans.

Nonsense-mediated mRNA decay (NMD) is one of the most extensively studied pathways of cytoplasmic mRNA degradation. It plays a critical role in diverse cellular processes by eliminating aberrant transcripts containing premature stop codons and by regulating the stability of physiological mRNAs. NMD factors were initially identified through genetic screens in S. cerevisiae (UPF1, 2, 3) and C. elegans (SMG-1, SMG5-7). Subsequent biochemical and genetic studies revealed the composition of NMD complexes and identified additional factors. A major protein hub for NMD is Upf1, an ATP-dependent RNA helicase that is part of two mutually exclusive NMD assemblies, the Upf1-Upf2-Upf3 complex and the Upf1-decapping complex, which contains the decapping enzyme and its co-factors. Here, we discuss recent findings, primarily from budding yeast, on the protein-protein interactions driving NMD complexes dynamics and their similarities to human NMD. Together, the N-terminal cysteine and histidine rich (CH) and helicase domains (HD) of Upf1 act as a hub for binding multiple partners. Upf1 is required for binding to NMD substrates and for the initiation of RNA degradation through decapping (yeast) or endonucleolytic hydrolysis (humans). We focus on the interplay between Upf2, Dcp2 and Nmd4 (yeast SMG6), which ensures the mutually exclusive formation of Upf1-bound subcomplexes modulating Upf1's affinity for RNA. Thus, the study of NMD factors interactions in different organisms sheds new light on the remarkable conservation of NMD molecular mechanisms.

Nonsense Mediated mRNA Decay↗

PubMed2026

Reinforcement learning-based dynamic ensemble for missense variant effect prediction and tiered prioritization of VUS.

BACKGROUND: Accurate classification of missense variants remains a challenging task despite major advances in genomics. Numerous computational models have been developed to assist in variant classification, but often require repeated integration and benchmarking efforts. Ensemble methods have been proposed to overcome the limitations of single predictors, but mostly rely on fixed, predefined weights that constrain their ability to capture interactions among predictive signals. METHODS: We present GenixRL, a dynamic ensemble framework that reformulates model fusion as a reinforcement learning optimization problem. GenixRL uses a Q-learning agent to learn a policy that dynamically weights the probabilistic outputs of complementary predictors, including BayesDel (addAF and noAF), ClinPred, and MetaRNN. Replacing static weighting with policy learning allows GenixRL to adaptively identify optimal weightings and substantially improve classification accuracy. RESULTS: In benchmark evaluation against 25 state-of-the-art predictors, GenixRL achieved an AUROC of 0.9644 on an independent ClinVar dataset. On saturation genome editing assays for BRCA1 and BRCA2, GenixRL achieved the best performance and ranked highest on 14 of 17 clinically significant genes in a zero-shot evaluation. Applied to uncertain and conflicting ClinVar variants, GenixRL enabled tiered, evidence-based prioritization of hundreds of thousands of variants as likely pathogenic or pathogenic with high confidence, supported by orthogonal population evidence from gnomAD. CONCLUSION: GenixRL advances pathogenicity prediction for missense variants and provides an adaptive ensemble that sorts variants of uncertain significance into tiered candidates for expert curation and functional validation.

Mutation, Missense↗

PubMed2026

The RrWRKY75-mediated activation of ascorbate synthesis in Rosa roxburghii Tratt contributes to salt stress tolerance.

L-Ascorbic acid (AsA) is a key antioxidant that alleviates oxidative stress in plants. Previous yeast one-hybrid (Y1H) screening identified RrWRKY75 as a transcription factor capable of binding to the promoter of RrGGP2 (GDP-L-galactose pyrophosphatase 2), a key structural gene responsible for massive AsA accumulation in Rosa roxburghii fruit. The function of RrWRKY75 in plant stress responses remains unclear. Here, RrWRKY75 is verified to specifically bind to the RrGGP2 promoter and activate its transcription. This positive regulatory effect on RrGGP2 transcript levels and AsA accumulation is further confirmed through overexpression or silencing of RrWRKY75 in R. roxburghii fruit or callus. Among various abiotic stress conditions, RrWRKY75 expression is significantly induced by salt stress. Upon its overexpression in callus or Arabidopsis thaliana, elevated AsA levels and antioxidant capacity are observed, thereby enhancing salt tolerance. Interestingly, RrWRKY75 also binds to the promoter of RrUNE12, a salt-responsive factor in R. roxburghii, and activates its expression. Moreover, yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assays confirm the physical interaction between RrWRKY75 and RrUNE12, which jointly upregulates RrGGP2 expression and AsA production. Collectively, RrWRKY75 boosts AsA biosynthesis and salt tolerance both by directly trans-activating RrGGP2 and by synergizing with RrUNE12 through transcriptional activation and protein complex formation. These findings provide insights into the regulatory role of RrWRKY75 in abiotic stress tolerance and offer valuable genetic resources for R. roxburghii germplasm improvement.

Rosa↗