Search Results (303)

Late-spring frost events severely damage low-chill peach blossoms, causing significant yield losses. Although 5-aminolevulinic acid (ALA) enhances cold tolerance through the PpC3H37-PpWRKY18 module, the regulatory mechanism of ALA on PpC3H37 remains to be elucidated. Using yeast one-hybrid screening with the PpC3H37 promoter as bait, we identified PpDof9 as a key interacting transcription factor. A genome-wide analysis revealed 25 PpDof genes in peaches (Prunus persica). These genes exhibited variable physicochemical properties, with most proteins predicted as nuclear-localized. Subcellular localization experiments in tobacco revealed that PpDof9 was localized to the nucleus, consistent with predictions. A synteny analysis indicated nine segmental duplication pairs and tandem duplications on chromosomes 5 and 6, suggesting duplication events drove family expansion. A conserved motif analysis confirmed universal presence of the Dof domain (Motif 1). Promoter cis-element screening identified low-temperature responsive (LTR) elements in 12 PpDofs, including PpDof1, PpDof8, PpDof9, and PpDof25. The quantitative real-time PCR (qRT-PCR) results showed that PpDof1, PpDof8, PpDof9, PpDof15, PpDof16, and PpDof25 were significantly upregulated under low-temperature stress, and this upregulation was further enhanced by ALA pretreatment. Our findings demonstrate ALA-mediated modulation of specific PpDof TFs in cold response and provide candidates (PpDof1, PpDof9, PpDof8, PpDof25) for enhancing floral frost tolerance in peaches. Full article

Heat stress transcription factor (Hsf) families play important roles in abiotic stress responses. However, previous studies reported that HsfBs genes may play diverse roles in response to heat stress. Here, we conducted functional analysis on a woodland strawberry Class B Hsf gene, FvHsfB1a, to improve thermotolerance. The structure of FvHsfB1a contains a typical Hsf domain for DNA binding at the N-terminus, and FvHsfB1a belongs to the B1 family of Hsfs. The FvHsfB1a protein was localized in the nucleus. The FvHsfB1a gene was expressed in various strawberry tissues and highly induced by heat treatment. Under heat stress conditions, ectopic expression of FvHsfB1a in Arabidopsis improves thermotolerance, with higher germination and survival rates, a longer primary root length, higher proline and chlorophyll contents, lower malonaldehyde (MDA) and O²⁻ contents, better enzyme activities, and greater expression of heat-responsive and stress-related genes compared to WT. FvWRKY75 activates the promoter of the FvHsfB1a gene through recognizing the W-box element. Similarly, FvWRKY75-OE lines also displayed a heat-tolerant phenotype, exhibiting more proline and chlorophyll contents, lower MDA and O²⁻ contents, and higher enzyme activities under heat stress. Taken together, our study indicates that FvHsfB1a is a positive regulator of heat stress. Full article

The soil-borne fungal pathogen Verticillium dahliae causes devastating vascular wilt disease in numerous crops, including cotton. In this study, we reveal that VdSOX1, a highly conserved sarcosine oxidase gene, is significantly upregulated during host infection and plays a multifaceted role in fungal physiology and pathogenicity. Functional deletion of VdSOX1 leads to increased fungal virulence, accompanied by enhanced microsclerotia formation, elevated carbon source utilization, and pronounced upregulation of effector genes, including over 50 predicted secreted proteins genes. Moreover, the VdSOX1 knockout strains suppress the expression of key defense-related transcription factors in cotton, such as WRKY, MYB, AP2/ERF, and GRAS families, thereby impairing host immune responses. Transcriptomic analyses confirm that VdSOX1 orchestrates a broad metabolic reprogramming that links nutrient acquisition to immune evasion. Our findings identify VdSOX1 as a central regulator that promotes V. dahliae virulence by upregulating effector gene expression and suppressing host immune responses, offering novel insights into the molecular basis of host–pathogen interactions and highlighting potential targets for disease management. Full article

Anthocyanins, crucial water-soluble pigments in plants, determine coloration in floral and fruit tissues, while fulfilling essential physiological roles in terms of plant growth, development, and stress adaptation. The biosynthesis of anthocyanins is transcriptionally regulated by WRKY factors, one of the largest plant-specific transcription factor families. Euscaphis japonica is an East Asian species, prized for its exceptionally persistent butterfly-shaped fruits that undergo pericarp dehiscence, overturning, and a color transition to scarlet red. This species represents an ideal system for studying anthocyanin regulation. However, the mechanisms by which WRKY transcription factors orchestrate anthocyanin accumulation during this process remain unknown. In this study, we identified 87 WRKY genes (EjaWRKYs) from the E. japonica genome. Phylogenetic analysis was used to classify these genes into three primary groups, with five subgroups, revealing conserved gene structures and motif compositions, supported by collinearity and comparative synteny analyses. Crucially, ten EjaWRKYs exhibited peak expression during the mature fruit stages, showing positive correlations with key anthocyanin biosynthesis genes. Functional validation through the use of transient transactivation assays in Nicotiana benthamiana confirmed that the five selected EjaWRKYs bind W-box elements and strongly activate reporter gene expression. Our results reveal EjaWRKYs’ regulation of anthocyanin accumulation in E. japonica fruit, provide the first comprehensive WRKY family characterization of this species, and establish a foundation for manipulating ornamental traits in horticultural breeding. Full article

Background/Objectives: Sweet potato is a tropical and subtropical crop and its growth and yield are susceptible to low-temperature stress. However, the molecular mechanisms underlying the low temperature stress of sweetpotato are unknown. Methods: In this work, combined transcriptome and metabolism analysis was employed to investigate the low-temperature responses of two sweet potato cultivars, namely, the low-temperature-resistant cultivar “X33” and the low-temperature-sensitive cultivar “W7”. Results: The differentially expressed metabolites (DEMs) of X33 at different time stages clustered in five profiles, while they clustered in four profiles of W7 with significant differences. Differentially expressed genes (DEGs) in X33 and W7 at different time points clustered in five profiles. More DEGs exhibited continuous or persistent positive responses to low-temperature stress in X33 than in W7. There were 1918 continuously upregulated genes and 6410 persistent upregulated genes in X33, whereas 1781 and 5804 were found in W7, respectively. Core genes involved in Ca²⁺ signaling, MAPK cascades, the reactive oxygen species (ROS) signaling pathway, and transcription factor families (including bHLH, NAC, and WRKY) may play significant roles in response to low temperature in sweet potato. Thirty-one common differentially expressed metabolites (DEMs) were identified in the two cultivars in response to low temperature. The KEGG analysis of these common DEMs mainly belonged to isoquinoline alkaloid biosynthesis, phosphonate and phosphinate metabolism, flavonoid biosynthesis, cysteine and methionine metabolism, glycine, serine, and threonine metabolism, ABC transporters, and glycerophospholipid metabolism. Five DEMs with identified Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were selected for correlation analysis. KEGG enrichment analysis showed that the carbohydrate metabolism, phenylpropanoid metabolism, and glutathione metabolism pathways were significantly enriched and played vital roles in low-temperature resistance in sweet potato. Conclusions: These findings contribute to a deeper understanding of the molecular mechanisms underlying plant cold tolerance and offer targets for molecular breeding efforts to enhance low-temperature resistance. Full article

Background/Objectives: Moso bamboo (Phyllostachys edulis), the most widely distributed bamboo species in China, is valued for both its shoots and timber. This species often faces challenges from high-temperature stress. To cope with this stress, Moso bamboo has evolved various adaptive mechanisms at the physiological and molecular levels. Although numerous studies have revealed that a large number of transcription factors (TFs) and genes play important roles in the regulatory network of plant heat stress responses, the regulatory network involved in heat responses remains incompletely understood. Methods: In this study, Moso bamboo was placed in a high-temperature environment of 42 °C for 1 h and 24 h, and transcriptome sequencing was carried out to accurately identify key molecules affected by high temperature and their related biological pathways. Results: Through a differential expression analysis, we successfully identified a series of key candidate genes and transcription factors involved in heat stress responses, including members of the ethylene response factor, HSF, WRKY, MYB, and bHLH families. Notably, in addition to traditional heat shock proteins/factors, multiple genes related to lipid metabolism, antioxidant enzymes, dehydration responses, and hormone signal transduction were found to play significant roles in heat stress responses. To further verify the changes in the expression of these genes, we used qRT-PCR technology for detection, and the results strongly supported their key roles in cellular physiological processes and heat stress responses. Conclusions: This study not only deepens our understanding of plant strategies for coping with and defending against extreme abiotic stresses but also provides valuable insights for future research on heat tolerance in Moso bamboo and other plants. Full article

The WRKY gene family comprises important transcription factors widely distributed in plants and plays significant roles in the growth and development, diverse (biotic and abiotic) stress responses, and various biological processes. In the current study, 96 identified HvLWRKY genes were classified into three groups and seven subgroups. Among these, 89 genes possessed the conserved domain WRKYGQK. A total of ten motifs were harbored in HvLWRKY genes with two to four introns. Fragmental duplication was suggested to be the prime force that drove the evolution of HvLWRKY genes. A high degree of collinearity was observed between barley and Triticum spelta. Cis-elements of HvLWRKYs were closely associated with abiotic stress, light response, and hormone response; however, there were differences in the numbers among groups. HvLWRKY genes, even the paralogous gene pairs, from different clades were differentially regulated under cold treatments in two landraces. HvLWRKY33, 43, 44, 57, 65, and 77 were homologous with the relative AtWRKY genes in Arabidopsis thaliana. They are suggested to regulate abiotic and pathogen resistance of two barley landraces via SA and JA pathways. Meanwhile, some genes (for example, HvLWRKY1 and HvLWRKY32) were specifically expressed in either cold-tolerant or cold-sensitive landraces. Under cold stress, different cold-responsive patterns occurred in different barley landraces. These findings provide a foundation for further studies on cold resistance in barley landraces and offer new insights for application of WRKY genes in barley breeding. Full article

Autophagy is an essential eukaryotic catabolic process through which damaged or superfluous cellular components are degraded and recycled via the formation of double-membrane autophagosomes. In plants, autophagy-related genes (ATGs) are primarily expressed in the cytoplasm and are responsible for orchestrating distinct stages of autophagosome biogenesis. Among these, ATG8 proteins, orthologous to the mammalian LC3 family, are conserved ubiquitin-like modifiers that serve as central hubs in selective autophagy regulation. Although ATG8 proteins are localized in both the cytoplasm and nucleus, their functions within the nucleus remain largely undefined. In the present study, the ATG8-interacting motif (AIM) was identified and functionally characterized in the potato ATG8 homolog (StATG8), demonstrating its capacity for selective target recognition. StATG8 was shown to form both homodimeric and heterodimeric complexes with other ATG8 isoforms, implying a broader regulatory potential within the ATG8 family. Notably, StATG8 was found to interact with the Ralstonia solanacearum type III effector PopP2, a nuclear-localized acetyltransferase, suggesting a possible role in effector recognition within the nucleus. In addition, interactions between StATG8 and transcription factors AtWRKY40 and AtWRKY60 were detected in both cytoplasmic autophagosomes and the nuclear compartment. These observations provide novel insights into the noncanonical, nucleus-associated roles of plant ATG8 proteins. The nuclear interactions with pathogen effectors and transcriptional regulators suggest that ATG8 may function beyond autophagic degradation, contributing to the regulation of nuclear signaling and plant immunity. These findings offer a foundational basis for further investigation into the functional diversification of ATG8 in plant cellular compartments. Full article

Selenium (Se), as a vital trace element, plays an important role in regulating the antioxidant systems of plants, strengthening photosynthetic capacity, and enhancing their stress resistance. Selenate and selenite are the dominant forms of Se available to plants in soils. This research takes highland barley as the research object, aiming to assess the impacts of plant growth, organic acid metabolite, and six transcription factor families in highland barley seedlings under varying concentrations of Na₂SeO₃. The study indicated that compared to the control group (CK), the plant height of highland barley seedlings under Se1 (0.02 g/kg Na₂SeO₃) treatment significantly increased by 66%. Under the Se2 (0.2 g/kg Na₂SeO₃) treatment, plant height significantly decreased by 28%. With Na₂SeO₃ concentration increased, the pigment content, O₂⁻ production rate, and soluble protein content in highland barley seedlings decreased, while the contents of soluble sugar, MDA, and H₂O₂ increased. Se1 treatment was found to be more beneficial for the growth and development of seedlings. The organic selenium in leaves and roots under Se2 treatment significantly increased by 1105-fold and 188-fold, respectively. The most effective migration capability from soil to leaf under Se1 or Se2 treatment was up to 6.15 or 6.56, respectively. Based on metabolomics, 30 differential metabolites of organic acids were screened from highland barley seedlings under Na₂SeO₃ treatment and showed positive correlationships with organic selenium, inorganic selenium, and total selenium in highland barley seedling leaves. Through transcriptome analysis, heatmap analysis on six major categories of transcription factors (bHLH, MYB, NAC, WRKY, GATA, and HSF) was performed. Under Se2 treatment, approximately two-thirds of the transcription factors showed high expressions. We further screened 26 differentially expressed genes (DEGs) related to Na₂SeO₃ concentration. Based on correlation analysis, there were six genes in the bHLH family, five in MYB, three in NAC, five in WRKY, and three in the GATA and HSF families that showed positive correlations with 30 differential organic acid metabolites. These results enhance our understanding of the relationship between the organic acid metabolites and transcription factor expression in highland barley seedlings under Na₂SeO₃ treatment. Full article

Vanillin, the principal aromatic compound in vanilla, is primarily derived from mature pods of vanilla (Vanilla planifolia Andrews). Although the biosynthetic pathway of vanillin has been progressively elucidated, the specific key enzymes and transcription factors (TFs) governing vanillin biosynthesis require further comprehensive investigation via combining transcriptomic and metabolomic analysis. For this study, V. planifolia (higher vanillin producer) and V. imperialis (lower vanillin producer) were selected. Time-series metabolomics analysis revealed 160–220 days after pollination (DAPs) as the critical phase for vanillin biosynthesis. Combined time-series transcriptome analysis revealed 984 upregulated differentially expressed genes (DEGs) in key periods, 2058 genes with temporal expression, and 4326 module genes through weighted gene co-expression network analysis (WGCNA), revealing six major classes of TFs: No Apical Meristem (NAC), Myb, WRKY, FLOWERING PROMOTING FACTOR 1-like (FPFL), DOF, and PLATZ. These TFs display strong regulatory relationships with the expression of key enzymatic genes, including P450s, COMT, and 4CL. The NAC TF family emerged as central regulators in this network, with NAC-2 (HPP92_014056) and NAC-3 (HPP92_012558) identified as key hub genes within the vanillin biosynthetic gene co-expression network. The findings of this study provide a theoretical foundation and potential target genes for enhancing vanillin production through genetic and metabolic engineering approaches, offering new opportunities for sustainable development in the vanilla industry and related applications. Full article

Mung bean (Vigna radiata L.) is globally cultivated and has been widely used in the food industries. Other than nutrients, the composition of the volatile organic compounds (VOCs) often influences the quality of mung bean-based products. However, the dynamics of VOCs and the flavor changes during mung bean seed development remain unexplored. This study investigated the VOC and flavor composition in four mung bean varieties by integrating relative odor activity value (ROAV) evaluation and transcriptomic analysis. A total of 65 VOCs were identified, with eucalyptol serving as a key maturity indicator in LL655 and SH-1, while nonanal contributed significantly to the characteristic beany flavor across all varieties. Transcriptomic analysis revealed four downregulated geranylgeranyl diphosphate synthase genes during seed development, leading to terpenoid accumulation patterns. Terpenoids, including trans-beta ocimene and gamma-terpinene, appeared to be regulated by transcription factors (TFs) from the RLK-Pelle, WRKY, AP2/ERF, bHLH, and bZIP families. Additionally, two MYB TFs showed potential roles in modulating the accumulation of phenylpropanoid/benzenoid derivatives. This study provides a comprehensive understanding of the VOC accumulation and flavor variation during mung bean seed development, enriches the knowledge of flavor chemistry in mung bean varieties, and facilitates a theoretical foundation for optimizing and developing mung bean-based products. Full article

The WRKY transcription factor family is a significant family of plant transcription factors (TFs). Plant growth and development are often influenced by abiotic factors, such as salinity and low temperature. Numerous studies have demonstrated that WRKY TFs primarily influence plant responses to adversity. However, there are few studies on the role of WRKY genes in the stress responses of Malus baccata (L.) Borkh. We cloned the MbWRKY33 gene from Malus baccata for this research, and its roles in salt stress tolerance were analyzed. Phylogenetic tree analysis revealed that MbWRKY33 and PbWRKY33 have the highest homology. Subcellular localization revealed that MbWRKY33 was located within the nucleus. An analysis of tissue-specific expression showed that MbWRKY33 had relatively high expression levels in young leaves and roots. Moreover, Arabidopsis thaliana plants overexpressing MbWRKY33 exhibited stronger resistance to salt stress compared with the wild type (WT) and the unloaded line empty vector (UL). Under the treatment of 200 mM NaCl, transgenic Arabidopsis thaliana plants exhibited significantly higher activities of antioxidant enzymes like superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) than the control. In contrast, the WT and the UL lines had elevated levels of malondialdehyde (MDA) and reactive oxygen species (ROS). In addition, MbWRKY33 elevates transgenic plant resistance to salt stress by regulating the expression levels of AtNHX1, AtSOS1, AtSOS3, AtNCED3, AtSnRK2, and AtRD29a. Results indicated that MbWRKY33 in Malus might be linked to high-salinity stress responses, laying a foundation for understanding WRKY TFs’ reaction to such stress. Full article

The SWEET gene family is a group of genes with important functions in plants that is mainly involved in the transport and metabolism of carbohydrate substances. In this study, 32 mango (Mangifera indica L.) SWEET genes were screened and identified at the whole-genome level through bioinformatics methods. A systematic predictive analysis was conducted on their physicochemical properties, homology relationships, phylogenetic relationships, chromosomal locations, genomic structures, promoter cis-acting elements, and transcription factor regulatory networks. Meanwhile, the transcription levels of mango SWEET genes in different varieties and at different fruit development stages were also analyzed to obtain information about their functions. These results showed that 32 mango SWEET genes were unevenly distributed on 12 chromosomes. Phylogenetic analysis divided the SWEET proteins of mango, Arabidopsis thaliana (L.) Heynh., and Oryza sativa L. into four clades; in each clade, the mango SWEET proteins were more closely related to those of Arabidopsis. Four types of cis-acting elements were also found in the promoter regions of mango SWEET genes, including light-responsive elements, development-related elements, plant hormone-responsive elements, and stress-responsive elements. Interestingly, we found that the Misweet3 and Misweet10 genes showed strong expression in different mango varieties and at different fruit development stages, and they both belonged to the fourth Clade IV (G4) in the phylogenetic tree, indicating that they play a key role in the sugar accumulation process of mango. In this study, the upstream transcription factors of Misweet3, Misweet8, Misweet9, Misweet10, Misweet17, Misweet18, Misweet19, Misweet21, Misweet23, Misweet25, Misweet27, and Misweet31, those that had high expression levels in the transcriptome data, were predicted, and transcription factors such as ERF, NAC, WRKY, MYB, and C₂H₂ were screened. The results of this study provide a new way to further study the regulation of mango SWEET family genes on sugar accumulation, highlight their potential role in fruit quality improvement, and lay an important foundation for further study of mango SWEET function and enhance mango competitiveness in fruit market. Full article

Drought stress limits plant survival and yield in arid regions. Uncovering the molecular mechanisms of drought tolerance is key to developing resilient crops. This study used Arabidopsis thaliana as a model to perform an in silico analysis of miRNA–mRNA interactions linked to post-transcriptional drought response. Using the MirTarget program, 274 miRNAs and 48,143 gene transcripts were analyzed to predict high-confidence miRNA–mRNA interactions based on binding free energies (−79 to −129 kJ/mole). Predicted binding sites were located in the CDS, 5′UTR, and 3′UTR regions of target mRNAs. Key regulatory interactions included ath-miR398a-c and ath-miR829-5p targeting ROS detoxification genes (CSD1, FSD1); ath-miR393a/b-5p and ath-miR167a-c-5p targeting hormonal signaling genes (TIR1, ARF6); and the miR169 family, ath-miR414, and ath-miR838 targeting drought-related transcription factors (NF-YA5, DREB1A, WRKY40). Notably, ath-miR414, ath-miR838, and the miR854 family showed broad regulatory potential, targeting thousands of genes. These findings suggest the presence of conserved regulatory modules with potential roles in abiotic stress tolerance. While no direct experimental validation was performed, the results from Arabidopsis thaliana provide a useful genomic framework for hypothesis generation and future functional studies in non-model plant species. This work provides a molecular foundation for improving drought and salt stress tolerance through bioinformatics-assisted breeding and genetic research. Full article

Rhododendron L., a renowned ornamental species and one of the ten famous flowers in China, is highly regarded for its aesthetic value and extensive applications in landscaping. However, its growth and quality are significantly compromised by drought stress, particularly in regions with dry conditions. To elucidate the drought response mechanisms of Rhododendron, two cultivars, ‘SaKeSiZhiXing’ (SKSZX) and ‘TuRuiMeiGui’ (TRMG), were subjected to natural drought stress, and changes in chlorophyll fluorescence and transcriptomic profiles were examined at 0 days (d), 4 d, and 8 d of drought exposure. An OJIP fluorescence transient (O-J-I-P) analysis revealed a progressive decline in the F_P parameter and an increase in the F_J parameter as drought stress intensified. Additionally, a delayed fluorescence (DF) analysis showed a gradual reduction in the I₁ and I₂ values within the induction and decay curves under prolonged drought conditions. The 820 nm curve indicated the deactivation of a transient phase characterized by a rapid decline, followed by a slow recovery in the modulated reflection (MR) signal. A transcriptomic analysis of leaves identified 24,352, 18,688, and 32,261 differentially expressed genes (DEGs) in SKSZX at 0 d, 4 d, and 8 d of drought treatment, respectively. In contrast, TRMG exhibited more pronounced and earlier drought-induced alterations. These DEGs were primarily enriched in pathways related to phenylpropanoid biosynthesis, plant hormone signaling, photosynthesis, and photosynthesis-antenna proteins. Additionally, 565 transcription factors (TFs) were identified, including bHLH, WRKY, bZIP, MYB-related, MYB, C2H2, and HSF families. The drought-induced changes in TRMG were more substantial and occurred earlier compared to SKSZX, with a greater impairment in the electron transfer capacity at both the donor and acceptor sides of photosystem II (PSII). This study provides valuable insights into the molecular mechanisms underlying drought tolerance in Rhododendron and offers a foundation for molecular breeding strategies aimed at enhancing drought resistance in future cultivars. Full article