Search Results (2,133)

Annamocarya sinensis is a Plant Species with Extremely Small Populations (PSESP) of great ecological and research value. Water conditions serve as a key environmental factor that profoundly shapes its growth, physiological homeostasis and stress adaptation. WRKY transcription factor families constitute the core molecular regulatory modules orchestrating plant responses to water-related stresses and environmental fluctuations. This study performs a systematic identification and bioinformatics analysis of the WRKY gene family in A. sinensis, combined with RT-qPCR to verify and analyze its expression patterns under water stress. The results identified a total of 92 WRKY genes unevenly distributed across 16 chromosomes, classified into three distinct subfamilies with obvious conservation of conserved motifs; the gene promoters were enriched with drought cis-elements, and fragment duplication drove the expansion of the family; this family had a high collinearity with the homologous genes of Arabidopsis thaliana, and its evolutionary function was conserved. RT-qPCR confirmed that AsWRKY3, AsWRKY11, AsWRKY17, AsWRKY53 and AsWRKY72 showed differential expression under water stress and were involved in regulating the processes of drought and waterlogging tolerance. Under drought stress, all five genes exhibited an upregulation trend, albeit with slightly varying response intensities; under waterlogging stress, AsWRKY3 and AsWRKY17 demonstrated strong enhanced responses, AsWRKY11 and AsWRKY53 showed early-response patterns, whereas AsWRKY72 exhibited a downregulation trend. In summary, fragment duplication and family differentiation enhanced the functional diversity of the WRKY family, providing a genetic basis for the adaptation of A. sinensis to changes in water availability. The research findings not only provide crucial theoretical clues for exploring the potential environmental adaptation and molecular evolution mechanisms of extremely small population plants, but also offer essential genetic resources and scientific foundations for species conservation, restoring wild populations, and conducting stress-resistant molecular breeding. Full article

Background/Objectives: The fibroblast-growth-factor 4 retrogene insertion on chromosome 12 (FGF4L2) is known to be associated with chondrodystrophy and intervertebral disc disease (IVDD), which increases the risk of Hansen’s type I intervertebral disc extrusion (IVDE) in Dachshunds. While the FGF4L2 insertion is known to occur at high frequency within the breed, subgroup-specific data relating to coat-type and size categories remain limited. This pilot study aimed to determine the distribution of FGF4L2 and wild-type (N) alleles in a cohort of Dachshunds registered with the German Dachshund Club (DTK) and to evaluate differences among coat and size varieties. Methods: A total of 488 Dachshund samples from the DNA archive of the Deutscher Teckelklub 1888 e.V. (DTK) were analysed and genotyped. Genotype data was categorised according to coat-type and size variant. Allele and genotype frequencies were calculated for the overall population and for each subgroup. Results: The overall frequency of the FGF4L2 insertion allele was 96.51% (95% CI: 95.17–97.50). However, there were moderate differences between subgroups. The allele was nearly fixed in several coat and size variants. Standard wire-haired Dachshunds had the lowest allele frequency (89.09%) and were the only group in which homozygous wild-type individuals were observed. Heterozygous frequencies peaked in standard smooth-haired (16.7%) and standard wire-haired (14.5%) groups. Conclusions: Because the FGF4L2 frequency differs meaningfully between Dachshund varieties, grouping them into a single breed, as many studies do, can obscure the residual subgroup-specific genetic variation present in this population. Analysing the varieties separately provides a basis for future studies investigating factors that may interact with FGF4L2 in IVDE, thereby highlighting its multifactorial nature. It also reveals where wild-type alleles persist, making genotype-informed, variety-specific breeding a viable strategy for improving vertebral column health. However, variation in FGF4L2 allele frequency alone may not fully account for the recently reported differences in vertebral column health between Dachshund coat varieties. Full article

Background/Objectives: Soybean (Glycine max) productivity is increasingly constrained by soil salinity. WIP transcription factors, a subfamily of C2H2-type zinc finger proteins, regulate cell division, differentiation, and tissue patterning in several plant species, but this gene family had not previously been systematically characterized in soybean or any other major legume crop. This study aimed to identify and characterize the GmWIP gene family genome-wide and evaluate its potential involvement in the soybean salt-stress response. Methods: Genome-wide identification of GmWIP genes was performed using sequence similarity and domain-based searches against the Wm82.gnm4.ann1 reference genome, followed by characterization of physicochemical properties, chromosomal distribution, phylogenetic relationships, gene duplication, conserved motifs, gene structure, and promoter cis-acting elements. Tissue-specific expression was examined using transcriptome data, and GmWIP responses to salt stress were profiled by RT-qPCR in roots, stems, and leaves of a salt-tolerant cultivar (HN531) and a salt-sensitive cultivar (HN563), alongside physiological measurements of oxidative stress and osmotic adjustment. Results: Thirty GmWIP genes were identified, with molecular weights from 26.90 to 57.52 kDa, distributed unevenly across 15 soybean chromosomes, with chromosomes 11, 12, and 13 forming a major hotspot (53.3% of the family). Duplication analysis detected 54 reconciled segmental duplicate gene pairs, all exhibiting Ka/Ks values < 1 (ranging from 0.0351 to 0.4471; mean 0.214), consistent with purifying selection acting on this gene set. GmWIP promoters were enriched for ABRE, MBS, and MeJA cis-acting elements. RT-qPCR showed genotype- and tissue-dependent differential expression under salt stress (e.g., up to 14.9-fold induction of GmWIP22 in HN531 stems), paralleled by superior proline accumulation (+45%), soluble sugars, and CAT activity (+38%) alongside reduced MDA accumulation in the tolerant cultivar. Conclusions: The GmWIP gene family has expanded substantially in soybean relative to previously characterized species and shows genotype-dependent transcriptional responses to salt stress, suggesting that specific GmWIP members are candidate regulators of salt tolerance and warrant further functional investigation. Full article

β-D-Xylosidases (BXLs) are members of glycoside hydrolase family 3. They play essential roles in cell wall remodeling, plant development, and abiotic stress responses. BXL gene families have been systematically characterized in several crop species. However, a comprehensive analysis of BXL genes in cotton (Gossypium hirsutum), a globally important fiber and oilseed crop, is still lacking. In this study, we performed a genome-wide identification of BXL genes in allotetraploid cotton. A total of 25 GhBXL genes were identified and classified into six phylogenetic clades. Gene structure and conserved domain analyses showed that all GhBXL proteins possess the characteristic tripartite GH3 domain architecture. Chromosomal distribution and synteny analyses indicated that the expansion of the cotton BXL family may be associated with whole-genome duplication and allopolyploidization. Promoter cis-element analysis detected stress-responsive regulatory motifs in the GhBXL promoters, including STRE, W-box, DRE core, and as-1 elements. Under PEG-simulated drought and salt stress, expression profiling, independently confirmed by qRT-PCR, showed distinct temporal response patterns among GhBXL members. Weighted gene co-expression network analysis (WGCNA) further identified GhBXL-8, GhBXL-9, and GhBXL-20 as hub genes in stress-responsive modules. Their co-expressed partners were enriched in transcription factors, kinases, and stress-related proteins. These findings provide a systematic foundation for understanding the evolutionary dynamics and functional roles of BXL genes in cotton. They also highlight candidate genes for future functional investigation. Full article

Satellite DNA is a dynamic component of plant genomes and a valuable source of cytogenetic markers, but its diversity and chromosomal distribution in polyploid Triticeae remain insufficiently studied. Here, low-coverage whole-genome sequencing, graph-based repeat clustering, quantitative PCR, multivariate statistics and fluorescence in situ hybridization (FISH) were used to identify and characterize satellite repeats in Elymus and related Triticeae species. Sixteen repeat clusters (E1–E16), with monomer lengths of 118–667 bp, showed distinct taxonomic distributions and copy-number profiles across 14 species. Correlation analysis, principal component analysis and hierarchical clustering revealed concerted variation among repeats and separated the perennial taxa Elymus and Pseudoroegneria from Triticum, Secale, Hordeum and Dasypyrum. Spearman correlation analysis identified E7 and E9 as putative candidates associated with St/StY genomic backgrounds, whereas E10 was identified as a putative candidate associated with the H genome. These statistical associations require independent cytogenetic validation. Contrasting copy numbers of E6 and E11 in bread wheat cv. Chinese Spring versus Dasypyrum villosum (L.) Candargy identified them as V-genome candidates. FISH localized E6 to the terminal regions of chromosomes 3VL, 4VS and 7VS, and E11 to 4VL. Karyotyping further revealed that two lines previously considered as wheat-D. villosum addition lines were in fact substitution lines: W3 was identified as a 3V(3D) substitution line and W4 as a 4V(4B) substitution line, whereas W7 retained its 7V addition status. These results expand the set of chromosomal markers for comparative genomics and introgression analysis in wheat. Full article

To address the issue of unbalanced path allocation in multi-UUV cooperative operations under inhomogeneous ocean environments during full-coverage search missions, this paper proposes a heterogeneous UUV path planning method that integrates a hybrid waypoint deployment strategy with a dual-chromosome co-evolutionary genetic algorithm. First, heterogeneous UUVs are adaptively assigned to sub-regions according to the search value of the sea area, and a combination of Poisson sampling and Voronoi iterative refinement is adopted to complete the layout of detection points. Subsequently, connectivity-constrained K-means clustering is introduced to decompose the multi-traveling salesman problem (MTSP) into several independent TSP sub-problems. Finally, a dual-chromosome encoding scheme for task sequences and split points is designed, and a penalty matrix is incorporated into the fitness function to account for obstacle avoidance constraints, thereby establishing an integrated genetic-algorithm-based solution framework that incorporates both decomposition and obstacle avoidance. Simulation results demonstrate that the proposed method reduces the number of planned detection points by 12.4%, 12.8%, and 9.3% compared with baseline methods in circular, rectangular, and irregular sea areas, respectively, while the optimal path lengths are shortened by 5.8%, 4.5%, and 5.9%. Moreover, the cooperative mission time with four UUVs is reduced by 73.9%, 72.7%, and 71.2% relative to a single UUV, demonstrating an approximately linear speedup relative to the number of UUVs. Convergence analysis and extended experiments on 15 instances further confirm the algorithm’s solution stability and robustness under varying regional scales, shapes, and obstacle configurations. These results validate that the proposed approach not only reduces the number of deployment points and path cost, but also effectively balances obstacle avoidance and multi-robot load distribution. Full article

Background: Prenatal diagnosis of congenital heart defects (CHD) is important for perinatal planning, yet the gestational week at which CHD is diagnosed varies considerably. In referred cohorts, diagnostic timing may be influenced by maternal, fetal, temporal, and lesion-specific factors. This study examined factors associated with the gestational week of prenatal diagnosis among pregnancies with prenatally recognized and subsequently confirmed CHD referred to a national tertiary fetal cardiology centre. Methods: This study analyzed 833 pregnancies with confirmed CHD managed between 2005 and 2020. The primary outcome was the gestational week of prenatal diagnosis. Univariable associations with binary predictors were assessed using Student’s t-test, Welch’s t-test, or the Mann–Whitney U test according to distributional assumptions. A primary fully adjusted multivariable linear regression model with heteroscedasticity-robust standard errors was used to evaluate variables associated with the gestational week of diagnosis. The model included maternal age, calendar year as a continuous variable, twin pregnancy, amniotic fluid abnormalities, chromosomal status, and selected lesion-specific diagnoses. Chromosomal status was modelled hierarchically as no chromosomal abnormality, Down syndrome, or other chromosomal abnormality. Results: In univariable analyses, advanced maternal age, Down syndrome, and chromosomal abnormalities were associated with earlier diagnosis, whereas oligohydramnios was associated with later diagnosis. In the primary fully adjusted multivariable model, increasing maternal age was associated with earlier diagnosis (β = −0.169 weeks per year, 95% CI −0.238 to −0.099; p < 0.001), as was later calendar year (β = −0.211 weeks per year, 95% CI −0.311 to −0.111; p < 0.001). Coarctation of the aorta/aortic arch stenosis (β = 2.276 weeks, 95% CI 0.787 to 3.764; p = 0.003), pulmonary stenosis (β = 1.996 weeks, 95% CI 0.376 to 3.617; p = 0.016), and oligohydramnios (β = 2.097 weeks, 95% CI 0.228 to 3.965; p = 0.028) were associated with later prenatal diagnosis. Down syndrome showed a borderline association with earlier diagnosis (β = −1.350 weeks, 95% CI −2.702 to 0.002; p = 0.050). The model explained 12.2% of the variability in the gestational week of diagnosis, with an adjusted R² of 0.107. Conclusions: In this tertiary referral-centre cohort of pregnancies with prenatally recognized and confirmed CHD, the gestational week of prenatal diagnosis was associated with maternal age, calendar year, oligohydramnios, and selected lesion-specific diagnoses. These findings should be interpreted as observational associations within an already recognized referral cohort rather than determinants of prenatal CHD detection in the general pregnant population. Future studies should incorporate referral pathways, screening history, ultrasound quality, operator experience, fetal position, and lesion-specific imaging characteristics to better characterize factors influencing the timing of prenatal CHD diagnosis. Full article

The FMD is an endangered species under first-class national protection in China. Comparative genomic investigation of microsatellite (SSR) in CDS may provide insights into adaptive evolutionary mechanisms and may inform conservation management strategies for captive populations. Here, we analyzed the FMD genome alongside five closely related ruminants: cattle (Bos taurus), red deer (Cervus elaphus), white-tailed deer (Odocoileus virginianus), sheep (Ovis aries), and goat (Capra hircus). Through genome-wide bioinformatic identification, we systematically compared the abundance, density, structural categories, repeat motifs, chromosomal distribution, and pathway enrichment analysis of SSR-containing genes in CDS. Furthermore, we performed synteny analysis and evaluated population genetic diversity. A total of 2509 SSRs in CDS were identified in the FMD, with a relative density of 62.61 loci/Mb. Trinucleotide SSRs were overwhelmingly dominant (88.46%) in the FMD. Notably, the FMD exhibited the highest relative abundances of both tetranucleotide and pentanucleotide repeats among the six species (2.37 and 2.18 loci/Mb, respectively), with pentanucleotide abundance approximately 5.6- to 9.1-fold higher than that of the other species. Chromosomal mapping revealed the highest SSR density in CDS regions on chromosome 27, while SSR-containing genes exhibited a heterogeneous pattern characterized by localized clustering. Synteny analysis demonstrated relatively conserved syntenic relationships between the FMD and goat, sheep, and cattle, with moderate conservation also observed with red deer and white-tailed deer, suggesting that SSR-containing genes in ruminants may remain highly conserved during chromosomal rearrangements. GO and KEGG analyses indicated that SSR-containing genes across all species were predominantly enriched in transcriptional regulation, RNA processing, and signal transduction pathways. Specifically, the FMD showed enrichment patterns associated with hypoxia response, mRNA processing, and epigenetic regulation, which may reflect lineage-specific transcriptional patterns, though the functional involvement of these SSRs remains to be experimentally validated. In addition, the five primer pairs screened in this study exhibited high polymorphism, with a mean polymorphism information content (PIC) of 0.93. The observed heterozygosity (Ho) was significantly lower than the expected heterozygosity (He), and the mean inbreeding coefficient (FIS) was 0.57, indicating heterozygote deficiency and an elevated risk of inbreeding in this captive FMD population. Collectively, our findings provide preliminary insights into the conserved patterns of microsatellite evolution and lineage-specific divergence in ruminants, offering a reference framework for comparative genomics and adaptive evolution research, as well as practical molecular markers for genetic management of captive populations. Full article

Antimicrobial peptides (AMPs) and AMP-like fragments are important components of vertebrate innate immunity, but their genome-wide diversification in amphibious fishes remains unclear. Here, we performed integrated bioinformatics and comparative genomic analyses of three representative mudskippers, Boleophthalmus pectinirostris (Bp), Periophthalmus magnuspinnatus (Pma), and Periophthalmus modestus (Pmo), together with zebrafish and humans as the reference vertebrates. Through genomics comparisons, we identified 708 putative AMP-derived genes in the three mudskipper genomes. Compared with zebrafish and humans, mudskippers contained fewer numbers of AMP-derived genes, indicating lineage-associated differences in repertoire size although their evolutionary basis remains unresolved. Several AMP-derived genes showed a pattern of clustered chromosomal distribution, such as histone-associated clusters on the Chr12 and Chr14 of the Bp genome. Histone H2B-derived sequences were highly conserved among various vertebrates, but mudskippers showed a distinct alanine-to-glycine substitution at position 66. In addition, a Misgurin-like fragment was located within TNNT3a rather than as an independent AMP gene. Compared with pond loach Misgurin, the synthetic Bp Misgurin-like fragment showed no detectable antibacterial activity against six tested bacterial strains under the tested assay conditions and concentration range, while this fragment was absent from the human TNNT3 gene. These findings provide new insights into AMP-derived sequence diversity, chromosomal organization, and potential immune adaptation in amphibious mudskippers, and offer candidate resources for future functional validation in medical and aquaculture applications. Full article

Rising temperatures pose daunting challenges for sustainable yield and nutritional quality of rice (Oryza sativa L.), thus putting food security at risk. Limited information exists regarding cis-acting regulatory elements and candidate genes controlling the heat shock transcription factor (HSF) gene family in rice. Therefore, the present study identified HSF genes in the japonica (Nipponbare) and indica (9311) rice cultivars through in silico repositories. Three candidate genes (HSFC2B, HSFB1, and HSFC2A) were selected for qRT-PCR analysis to validate their expression patterns under heat stress (HS). The present findings reported a total of 25 OsHSF genes through in silico genome-wide identification. Comparative analysis illustrated that the OsHSF genes had structural similarities but different expression and transcriptional regulation between the two cultivars. HSF genes were unevenly distributed across the 12 rice chromosomes, suggesting that tandem duplication and gene repetition may have contributed to the evolution of novel genes. Phylogenetic analysis revealed that all OsHSF gene family members have shared common ancestry, but several genes lack introns, potentially facilitating swift stress responses as indicated by gene structure analysis. Expression analysis revealed that candidate genes were active, with HSFC2A exhibiting the highest level of expression in the japonica cultivar compared to indica under heat-stressed conditions. HSFC2B gene showed a higher statistical difference in its response between cultivars, time points, and cultivar vs. time points interactions compared to HSFC2A and HSFB1. These findings offer valuable insights into the function of OsHSF genes that will contribute to the development of climate-resilient rice cultivars. Full article

Fibrillins (FBNs) are conserved plastid-associated proteins implicated in plant development and abiotic stress responses; however, their roles in maize remain unclear. In this study, through a genome-wide bioinformatic analysis, we identified 14 ZmFBN genes in the maize genome and characterized their phylogeny, chromosomal distribution, gene structure, conserved motifs, and promoter cis-elements. ZmFBN members were grouped into several subfamilies that all retain a conserved PAP_fibrillin domain, whereas the variation in exon–intron organization, motif composition, and regulatory elements suggests functional diversification. Expression profiling revealed pronounced tissue-preferential patterns, with many genes highly expressed in leaves and reproductive tissues, and distinct responses to drought, salt, heat, and cold stresses. qRT-PCR assays showed that ZmFBN8 and ZmFBN9 are strongly induced by both salt and PEG-simulated drought, ZmFBN2 and ZmFBN5 are predominantly drought-responsive, and ZmFBN11 is mainly activated by salt. Genome-wide association analysis further detected significant loci near ZmFBN1 and ZmFBN4, whose allelic variants are associated with the survival rate under drought and with key agronomic traits, including the tassel branch number, flowering time, ear diameter, and kernel length. These results demonstrate that ZmFBN genes make diversified contributions to maize growth, development, and stress adaptation and highlight several members as promising targets for functional studies and the molecular breeding of stress-tolerant maize. Moreover, selection pressure analysis indicated ZmFBN7 experienced relaxed purifying selection, and ZmFBN12 underwent positive selection, which drives the functional diversification of the ZmFBN family during maize evolution. Full article

Potassium (K⁺) is an essential mineral element for plant growth and development. Members of the HAK/KUP/KT (HAK) gene family serve pivotal roles in K⁺ uptake, translocation and homeostasis. Although numerous HAK genes have been extensively identified across diverse plant species, a comprehensive genomic and functional analysis of this family in sweet potato (Ipomoea batatas L.) remains lacking. In this study, 22 putative IbHAK genes were identified and classified into four distinct clades (I–IV). A systematic characterization was performed for each IbHAK gene, including protein physicochemical properties, chromosome distribution, gene structure, synteny, and promoter cis-elements. Notably, five IbHAK5 genes (IbHAK5A–IbHAK5E) clustered on the HAK gene tree with AtHAK5, OsHAK5, and ZmHAK5. This suggests that small-scale duplication events likely drove the expansion of HAK5 in sweet potato. Among them, IbHAK5A, a gene with broad expression across tissues and strong transcriptional induction under low-K⁺ (LK) stress, was cloned. The function was then characterized in a K transporter-deficient yeast mutant and an Arabidopsis hak5 mutant. Transcription factor IbPTL1 directly binds the IbHAK5A promoter, upregulates its expression, and integrates into the K⁺ signaling. In this work, we provide foundational insights into the underlying molecular mechanisms governing K⁺ acquisition in sweet potato. Full article

Brassinosteroid signaling kinases (BSKs) act as core signal transducers downstream of Brassinosteroid (BR) perception and integrate plant growth regulation with broad-spectrum biotic and abiotic stress tolerance. Despite well-established functional characterizations of BSK gene families in Arabidopsis thaliana and rice, comprehensive genome-wide profiling and salt response analysis of BSK homologs remain lacking in wheat. In this study, we systematically identified 18 TaBSK family members. Phylogenetic analysis separated wheat TaBSKs into three distinct evolutionary subgroups. The 18 TaBSK loci were unevenly distributed across 14 chromosomes derived from the A, B, and D subgenomes. Motif scanning uncovered 10 universal conserved amino acid motifs, including two signature functional domains: the tetratricopeptide repeat (TPR) and protein kinase catalytic domain (PKc). Intra-genomic collinearity analysis confirmed that segmental duplication constituted the primary evolutionary driver underlying TaBSK family expansion. Extensive cis-regulatory element profiling identified abundant hormone- and stress-responsive cis-motifs. Transcriptome profiling RNA-seq datasets revealed five TaBSK genes exhibiting significant differential transcription under salt stress. Specifically, TaBSK16, TaBSK17, and TaBSK18 were markedly upregulated following salt exposure. Collectively, this study delivers an evolutionary and transcriptional atlas of the wheat TaBSK family and provides candidate genes for functional validation and molecular breeding toward salt-tolerant wheat varieties. Collectively, this study explores the evolution and transcriptional patterns of the wheat TaBSK gene family and provides candidate genes for subsequent functional validation and molecular breeding of salt-tolerant wheat varieties. Full article

Eggplant (Solanum melongena L., 2n = 2x = 24) is one of the most economically important crop species of the Solanaceae family. In recent decades, various approaches have enabled the identification of Solanum insanum as the direct ancestor and Solanum incanum as the closest wild relative; however, these studies have largely neglected chromosomal features. To expand the chromosome knowledge of eggplant and its ancestors, we performed a comparative cytogenetic study by combining karyomorphological analyses with Fluorescence In Situ Hybridization (FISH) and Genomic In Situ Hybridization (GISH). The three species exhibited similar chromosome morphology, except for the NOR-bearing chromosomes, which distinguished the S. incanum karyotype from those of the other two species. rDNA FISH mapping revealed two distinct patterns: one common to eggplant and S. insanum, and the other exclusive to S. incanum. The s-GISH method, used to examine the chromosome distribution of satDNA repeats, revealed identical patterns, which suggests that the chromosome structure of the investigated species was conserved during their evolution. Hybridization signals from cross-GISH experiments aligned with s-GISH patterns and confirmed the genomic homology among S. melongena, S. insanum and S. incanum. Our study provided novel cytogenetic evidence clarifying the evolutionary relationships between the cultivated eggplant and its ancestors. Full article

The dried roots and rhizomes of Salvia miltiorrhiza are widely used and economically important traditional Chinese medicinal materials. Land salinization affects the growth of S. miltiorrhiza, resulting in a decline in its quality and yield. WNK kinases belong to a unique family of serine/threonine kinases. They act as key regulators of plant growth, development and abiotic stress responses. However, this gene family has not been systematically characterized in Salvia miltiorrhiza. In this study, nine SmWNK genes were identified at the whole-genome level in S. miltiorrhiza. Phylogenetic analysis classified them into four structurally conserved subgroups. These genes are distributed across eight chromosomes and contain two pairs of intraspecific syntenic genes. Interspecific collinearity is far stronger between S. miltiorrhiza and dicots than between S. miltiorrhiza and monocots. Cis-element prediction indicated these cis-elements participate in light signaling, hormone responses, stress responses and developmental regulation. Quantitative real-time PCR revealed that eight SmWNK genes were significantly induced by salt stress, and SmWNK7 was selected as the key candidate for functional validation. Functional assays via heterologous overexpression in tobacco demonstrated that SmWNK7 overexpression promoted root elongation and enhanced salt tolerance. Compared with wild-type tobacco plants, SmWNK7-overexpressing transgenic tobacco lines had higher catalase (CAT) and peroxidase (POD) activities, lower malondialdehyde (MDA) content, and stronger root viability. These changes alleviated oxidative damage by enhancing the antioxidant defense system. Yeast two-hybrid screening yielded 40 SmWNK7-interacting annotated proteins, including 6 transcription factors and 1 protein kinase, which were enriched in 81 GO terms and 27 KEGG pathways. These findings confirm SmWNK7 positively regulates root growth and salt tolerance, laying a theoretical foundation for exploring SmWNK genes’ role in plant stress adaptation. Full article