Search Results (1,548)

Sainfoin (Onobrychis viciifolia Scop.) is an important legume forage. Its anthocyanidin reductase (ANR) catalyzes the conversion of anthocyanins to epicatechins. This conversion reaction is not only a key step in the biosynthesis of proanthocyanidins (PAs) but also directly influences both forage quality and stress resistance. Here, we systematically identified 67 ANR gene family members in autotetraploid sainfoin for the first time. Using bioinformatics approaches, we analyzed gene structure, conserved domains, motifs, and cis-regulatory elements of the identified ANR genes. In this study, phylogenetic analysis revealed that the ANRs clustered into 11 distinct clades, with genes within the same clade predominantly originating from closely related species within the same family. Significant collinearity with Arabidopsis thaliana, Glycine max, Cicer arietinum, and Medicago truncatula further revealed the conserved evolutionary path of this gene family. RT-qPCR analysis showed differential expression patterns of OvANRs in root, stem, and leaf tissues. For instance, OvANR19 was significantly induced by abscisic acid (ABA) and methyl jasmonate (MeJA), with its expression upregulated by 79.7-fold and 3.8-fold in roots and by 16.2-fold and 31.3-fold in leaves. Furthermore, subcellular localization analysis confirmed that representative ANR proteins were localized in the cytoplasm. This study lays a foundation for molecular breeding aimed at enhancing stress resistance and forage quality in sainfoin. Full article

Abscisic acid (ABA) is a “classical” plant hormone and is key to many plant responses, notably seed germination, transpiration and defence. It is becoming increasingly clear that ABA acts not just through the canonical PYL/PYR/RCAR receptors but also through other proteins that can interact specifically with ABA. Here we use genomic and transcriptomic resources to show that the human proteome also contains proteins with specific ABA-binding signatures and that some of these potential ABA-binding proteins may have roles in cancer and diabetes. In addition, there is evidence for the presence of ABA in humans; however, the source of it remains somewhat inconclusive. Here we propose an ABA synthesis pathway that, much like in fungi, does not include carotenoids but proceeds via farnesyl pyrophosphate. In summary, we review the current status of ABA research in Homo sapiens and propose avenues that might lead to novel insights into the synthesis and biological roles of this ancient hormone, e.g., in obesity and inflammation. Full article

Phosphoenolpyruvate carboxylase (PEPC) is a crucial enzyme in plant photosynthesis and stress responses, yet its gene family remained uncharacterized in Zanthoxylum armatum. This study presents the first genome-wide identification and comprehensive analysis of the PEPC gene family in Z. armatum. A total of 12 ZaPEPC genes were identified and classified into plant-type (PTPC) and bacterial-type (BTPC) subfamilies based on phylogenetic analysis. These genes exhibited conserved protein domains but distinct gene structures, with evidence of gene duplication events contributing to family expansion. Promoter analysis revealed an abundance of stress- and hormone-responsive cis-elements, particularly those related to light, abscisic acid (ABA), and methyl jasmonate (MeJA). Expression profiling demonstrated that ZaPEPC genes display environment-specific expression patterns, with ZaPEPC7 and ZaPEPC11 showing significantly higher expression in high-altitude, high-light environments (Yunnan) compared to other regions (Shandong and Chongqing). Co-expression network analysis further indicated interactions between specific ZaPEPCs and stress-related transcription factors. These findings systematically reveal the molecular characteristics and potential roles of the ZaPEPC gene family in environmental adaptation, providing valuable genetic resources and a theoretical foundation for improving stress tolerance and photosynthetic efficiency in Z. armatum through molecular breeding. Full article

Understanding the molecular crosstalk between drought and iron (Fe) homeostasis is crucial for developing drought-tolerant wheat cultivars with enhanced nutrient quality. In this study, transcriptomic data mining identified 23,271 and 5933 differentially expressed genes (DEGs) under drought and Fe deficiency, respectively, with 2479 DEGs in response to both stresses. Notably, this overlapping set included significant numbers of genes encoding transcription factors (TFs) (149 genes), Fe homeostasis components (274 genes), and those involved in phytohormones pathways (245 genes), particularly the abscisic acid (ABA) pathway. Gene Ontology (GO) analysis revealed specific and commonly affected biological processes, such as response to abiotic stimulus and heme binding. Furthermore, co-expression network analysis revealed modules highly enriched with genes involved in transcriptional regulation and Fe uptake, enabling the identification of key hub regulatory genes, belonging to the MYB, NAC, BHLH, and AP2/ERF families, involved in the shared stress response. Finaly, the expression of a set of candidate TF-encoding genes was validated using qRT-PCR in durum wheat under drought and Fe starvation, providing a detailed overview of the possible shared regulatory mechanisms linking drought and Fe deficiency responses. Full article

Coconut yield and quality are significantly affected by multiple female inflorescences (MFF), which disrupt flower differentiation balance. To elucidate the molecular mechanisms, we compared MFF with normal female inflorescences (NFF) using phenotypic, morphological, physiological, and multi-omics approaches. The results revealed that MFF exhibited altered flower structures. MFF showed elevated iron (Fe), nitrogen (N), sulfur (S), potassium (K), calcium (Ca), zinc (Zn), proline (Pro), catalase (CAT), malondialdehyde (MDA), abscisic acid (ABA), and jasmonic acid (JA), but reduced molybdenum (Mo), soluble sugar (SS), soluble protein (SP), superoxide dismutase (SOD), peroxidase (POD), indole acetic acid (IAA), zeatin riboside (ZR), and gibberellic acid (GA). We detected 445 differentially expressed genes (DEGs) mainly enriched in ABA, ETH, BR, and JA pathways in MFF compared to NFF. We identified 144 differentially accumulated metabolites (DAMs) primarily in lipids and lipid-like molecules, phenylpropanoids and polyketides, as well as organic acids and derivatives in the comparison of MFF and NFF. Integrated analysis linked these to key pathways, e.g., “carbon metabolism”, “carbon fixation in photosynthetic organisms”, “phenylalanine, tyrosine, and tryptophan biosynthesis”, “glyoxylate and dicarboxylate metabolism”, “glycolysis/gluconeogenesis”, “pentose and glucuronate interconversions”, “flavonoid biosynthesis”, “flavone and flavonol biosynthesis”, “pyruvate metabolism”, and “citrate cycle (TCA cycle)”. Based on our results. the bHLH137, BHLH062, MYB (CSA), ERF118, and MADS2 genes may drive MFF formation. This study provides a framework for understanding coconut flower differentiation and improving yield. Full article

The objective of this work was to assess the association of ACC (1-aminocyclopropane-1-carboxylic acid), S-ABA (abscisic acid), and ethephon on color development and anthocyanin accumulation in berries, as well as on other quality attributes of ‘Benitaka’ and ‘Rubi’ table grapes grown in a subtropical region, in addition to postharvest conservation of clusters and vine regrowth. As a statistical model, a randomized block design consisting of nine treatments and four replications was used. The treatments included different associations of ACC, S-ABA, and ethephon, by using the commercial formulations Accede^®, ProTone^®, and Ethrel^® containing 400 g kg⁻¹ of ACC, 100 g L⁻¹ of S-ABA, and 720 g L⁻¹ of ethephon, respectively. The total anthocyanins, berry color index (CIRG), physicochemical characteristics, and cluster color coverage were assessed weekly, while berry firmness was assessed at harvest. After being harvested, the clusters were placed under cold storage at 1.0 ± 1.0 °C, and after 45 days, their postharvest attributes were assessed, as well as the vine regrowth in the following season. The exogenous and combined application of compounds at véraison was demonstrated to be a strategy to trigger the development of color in ‘Benitaka’ and ‘Rubi’ table grapes. For the ‘Benitaka’ table grape, the clusters treated with the different combinations of ACC and S-ABA, ethephon and S-ABA, or ethephon alone resulted in the highest concentration of total anthocyanins and the highest CIRG means (4.90; 4.86; 4.82; 4.81, 4.73, and 4.70 mg g⁻¹ for anthocyanins, and 6.12, 6.08, 5.97, 5.92, 5.85, and 5.74 for CIRG, respectively). For the ‘Rubi’ table grape, the combinations of ACC and S-ABA at 7 days after véraison (DAV), or ethephon and S-ABA at 7 and 14 days, resulted in higher means of anthocyanins and CIRG (3.86, 3.51, and 3.40 mg g⁻¹ for anthocyanins and 5.05, 4.68, 4.82, and 4.79 for CIRG, respectively). Furthermore, the firmness of the berries of both cultivars remained unchanged, and after 45 days of cold storage, no reduction in the quality of the evaluated postharvest attributes was found. It was concluded that a single application of ACC 0.20 g L⁻¹ + S-ABA 0.250 g L⁻¹ at 7 DAV was sufficient to promote the accumulation of anthocyanins and resulted in an intense and uniform color in the berries for both varieties assessed, with no adverse impacts on the postharvest conservation of the clusters or on the regrowth of the vines. The significance of this research was to demonstrate that table grapes with insufficient skin color can be improved through a combination of S-ABA and ACC at lower concentrations of active ingredients. Full article

Soil salinization significantly limits plant growth and agricultural productivity, with MYB transcription factors playing crucial roles in mediating plant responses to salt stress. In this study, a novel R2R3-MYB transcription factor gene, SlMYB306-like, was isolated from tomato. Phylogenetic comparison indicated that SlMYB306-like shared the highest sequence homology with potato StMYB306-like. Subcellular localization assays demonstrated nuclear localization of SlMYB306-like protein, while yeast transactivation assays confirmed its function as a transcriptional activator. Expression profiling showed that SlMYB306-like was inducible by NaCl and abscisic acid (ABA) treatments. In addition, functional characterization via the overexpression of SlMYB306-like in Arabidopsis thaliana revealed enhanced salt tolerance, evidenced by an increased maximum quantum efficiency of photosystem II (Fv/Fm) and proline levels alongside decreased accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA) content under salt stress conditions. Furthermore, the overexpression of SlMYB306-like upregulated the expression of several stress-responsive genes, including AtSOD1, AtCAT1, AtEGY3, AtP5CS2, and AtRD29A. Collectively, these findings suggest that SlMYB306-like enhances salt tolerance by modulating ROS scavenging, osmotic adjustment, and ABA signaling pathways, thereby representing a promising candidate gene for the development of salt-tolerant crops. Full article

Litchi is an important subtropical fruit, highly valued by consumers for its vibrant color and distinctive flavor. B-box (BBX) proteins, which are zinc finger transcription factors, play a crucial role in regulating plant growth, development, and stress responses. Nevertheless, the specific function of BBX genes in the development and coloration of litchi fruit remains inadequately understood. In this study, 21 LcBBX genes (designated as LcBBX1-LcBBX21) were identified within the litchi genome. These genes were categorized into five sub-families based on phylogenetic analysis and were found to be unevenly distributed across 12 chromosomes. Promoter analysis revealed a rich presence of light-responsive elements, such as the G-box, and abscisic acid (ABA) responsive elements, including ABRE, within the promoter regions of LcBBX genes. Protein–protein interaction predictions indicated that the majority of LcBBX genes have the potential to interact with the light-responsive factor HY5. Transcriptome analysis and qRT-PCR results demonstrated that LcBBX genes exhibit tissue-specific expression patterns. Notably, most LcBBX genes were highly expressed prior to fruit coloration, whereas LcBBX4 and LcBBX10 were upregulated during the fruit coloration phase. Furthermore, LcBBX1/4/6/7/15/19 were upregulated in response to light following the removal of shading. The findings suggest that LcBBX4 may directly regulate anthocyanin biosynthesis in litchi pericarp. This study provides critical insights into the molecular mechanisms underlying litchi fruit development and coloration. Full article

Agave species possess substantial cultural, ecological, and economic significance, particularly in Mexico, where they are traditionally utilized for food, fiber, and beverages. Their industrial relevance has expanded to include bioenergy, nutraceuticals, and sustainable agriculture. However, conventional propagation methods are constrained by long life cycles, low seed germination rates, and susceptibility to phytopathogens. In vitro culture has emerged as a pivotal biotechnological strategy for clonal propagation, germplasm conservation, and physiological enhancement. This review presents a critical synthesis of plant growth regulators (PGRs) employed in agave micropropagation, emphasizing their roles in organogenesis, somatic embryogenesis, shoot proliferation, and rooting. Classical PGRs such as 6-benzylaminopurine (BAP), benzyladenine (BA), 2,4-dichlorophenoxyacetic acid (2,4-D), indole-3-acetic acid (IAA), and indole-3-butyric acid (IBA) are widely utilized, with BA + 2,4-D and BA + IAA combinations demonstrating high efficiency in embryogenic callus induction and shoot multiplication. Additionally, non-traditional regulators such as abscisic acid (ABA) and putrescine (Put) have been shown to affect embryo maturation. This review synthesizes recent studies on agave in vitro culture protocols, identifies trends in PGR use, and highlights key research gaps. These insights reveal opportunities for innovation and underscore the need for species-specific optimization and molecular validation to improve reproducibility and scalability. Full article

Triterpenoid saponins are important secondary metabolites in plants. Abscisic acid (ABA), as one of the indispensable regulatory hormones in plants, promotes the accumulation of bioactive components in various plants, including triterpenoid saponins; however, its induced mechanism in Hedera helix remains unclear. In this study, the treatment of H. helix leaves with 100 μM ABA led to the identification of 7108 differentially expressed genes (DEGs) within 6 h post-treatment through transcriptomic and bioinformatic analysis. Enrichment analyses of GO terms and KEGG pathways indicated significant enrichment of DEGs in terpenoid backbone biosynthesis pathways. Analysis of DEGs revealed the NAC transcription factor, which is crucial for plant growth regulation, stress response, and secondary metabolite biosynthesis. A total of 182 HhNACs were identified at the genome-wide level, named HhNAC1 to HhNAC182 according to their chromosomal positions. Numerous ABA-responsive cis-regulatory elements (CREs) were presented at upstream promoters of HhNAC1 to HhNAC182. They demonstrated diversified tissue-specific expression profiling among stems, roots, and leaves of H. helix. Notably, HhNAC93 was predominantly expressed in H. helix leaves. Correlation analysis unveiled a markedly positive relationship among ABA-induced HhNAC93 expression, triterpenoid saponin accumulation, and the expression of essential saponin biosynthetic genes. HhNAC93 likely functions as a candidate regulator in triterpenoid saponin biosynthesis. These findings provide crucial evidence for further exploring the biological role of HhNAC transcription factor in H. helix. Full article

Improving plant water use efficiency (WUE) and drought tolerance by modulating stomatal activity constitutes a promising strategy for mitigating the impacts of water scarcity. SnRK2, a key component of the abscisic acid (ABA) signaling pathway, plays a critical role in modulating stomatal behavior under abiotic stress. However, the functional role of SnRK2 in regulating stomatal movement to enhance WUE and drought tolerance in Populus euphratica remains to be characterized. In this study, 11 PeSnRK2 genes were identified in the P. euphratica genome, each comprising 9–14 exons and exhibiting an uneven distribution across seven chromosomes. Subcellular localization predictions indicated that these proteins are predominantly localized in the Cytoplasm and Cytoskeleton. Phylogenetic analysis grouped the PeSnRK2 genes into three distinct subfamilies, and conserved gene structures were observed within each clade. Analysis of cis-acting regulatory elements suggested that PeSnRK2 genes were involved in hormonal signaling and stress response pathways. Further transcriptomic data also indicated substantial alterations in PeSnRK2 expression due to polyethylene glycol (PEG) and abscisic acid (ABA) treatment. Finally, qRT-PCR and subcellular localization showed that PeSnRK2.6 is highly induced by ABA and functions in both nucleus and cytoplasm. This first characterization in a desert woody species bridged gaps in SnRK2 evolution and function. Full article

Different pollination methods can affect the development and quality of watermelon fruit. The physiological changes in the early development of watermelon after using different pollination methods are unclear. In this study, we focused on the effects of hand pollination (H), honeybee pollination (HB), and bumblebee pollination (BB) at 1 day after pollination (1DAP) on the fruit setting rate, size, and endogenous hormone, gene, and protein expression levels using the transcriptome and proteome in greenhouse watermelon. Thus, we studied the physiological indicators of the final fruit at 40 DAP. At 1 DAP, the fruit setting rate and size of watermelon embryos showed no significant differences between the three groups. The indole-3-acetic acid (IAA) and isopentenyl adenosine (iPA) contents in the H group were highest, followed by the BB group and HB group. The abscisic acid (ABA) and gibberellin (GA3) contents were significantly higher in the BB group than in the H and HB groups. The zeatin (ZT) and carotenoid contents were lowest in the H group. The DEGs in H vs. HB and H vs. BB were mainly involved in plant hormone signal transduction, as well as amino acid and lipid metabolism. Moreover, phenylpropanoid biosynthesis and carotenoid biosynthesis were involved in H vs. HB, and carbohydrate metabolism was involved in H vs. BB. The DEGs in HB vs. BB were mainly involved in pathways including zeatin biosynthesis and photosynthesis. The DEPs in H vs. HB and HB vs. BB were involved in flavonoid biosynthesis, whereas the DEPs in H vs. BB were involved in ribosomes and oxidative phosphorylation. At 40 DAP, bee pollination can promote sugar content and transportation. Functional and pathway changes among key genes and proteins and pheromones may co-regulate plant development. This study provides data support for exploring the effects of pollination techniques on watermelon fruit development under greenhouse conditions. Full article

In rice (Oryza sativa L.), the short-chain dehydrogenase protein OsABA2 plays a crucial role in regulating abscisic acid (ABA) biosynthesis. However, little is known about the other proteins that interact with OsABA2 to regulate ABA biosynthesis. Using yeast two-hybrid screening, we identified a novel OsABA2 interacting protein OsPP2C55, which contains a serine/threonine phosphatase (family 2C) catalytic domain. The yeast two-hybrid (Y2H) assay and firefly luciferase complementary imaging (LCI) assay confirmed these interactions. Subsequent studies revealed that saline–alkaline stress significantly downregulated OsPP2C55 gene expression. Meanwhile, we constructed ospp2c55 CRISPR gene knockout (ospp2c55-KO) plants using Agrobacterium genetic transformation. Compared with wild-type plants, ospp2c55-KO plants under saline–alkaline stress exhibited significantly elevated OsABA2 protein levels, leading to substantial increases in ABA content. In addition, ospp2c55-KO plants demonstrated heightened sensitivity to ABA during seed germination. Moreover, ospp2c55-KO plants improved the survival rate and stress-related indices of rice seedlings under saline–alkaline stress, and upregulated the expression of genes related to adversity stress (OsNCED1, OsNCED3, OsABA2, OsSODCc2, and OsCatB). We found that OsPP2C55 plays a negative regulatory role in ABA biosynthesis and saline–alkaline stress tolerance in rice. Full article

The phytohormone abscisic acid (ABA) plays a central role in organizing adaptive responses in plants to various abiotic stresses, helping the plant minimize the negative impact on growth and development. Rapid and direct detection of ABA is valuable for investigating plant responses to abiotic stress. In this work, we propose a novel label-free, non-competitive immunoassay for detecting and quantifying ABA easily and rapidly using a surface plasmon resonance (SPR) biosensor. The SPR sensor chip was functionalized with a commercial anti-ABA antibody, characterized for its affinity, binding kinetics, and specificity using the same platform. The direct assay demonstrated high specificity and sensitivity, with a calculated limit of detection of 1.36 ng/mL in buffer. The new immunosensor was applied to determine ABA concentrations directly in xylem sap samples from tomato plants subjected to abiotic stress (drought and high salinity) and was able to accurately reflect ABA levels corresponding to the applied stress. The results were comparable to the reference method, ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS), establishing this new immunosensor as a novel detection method for rapid and reliable monitoring of ABA levels associated with abiotic stress in tomato plants. Full article

Tyrosine (Tyr) degradation is a crucial pathway in animals. However, its role in plants remains to be examined. Fumarylacetoacetate hydrolase (FAH) is the final enzyme involved in Tyr degradation. Studies of a mutant of the SHORT-DAY SENSITIVE CELL DEATH 1 (SSCD1) gene encoding FAH in Arabidopsis have shown that blockage of this pathway results in the accumulation of Tyr metabolites, thereby inducing cell death under short-day conditions. Seed dormancy is a critical trait which is regulated by endogenous and environmental cues, among which abscisic acid (ABA) and gibberellin (GA) are the primary effectors. ABA induces seed dormancy, whereas GA releases seed dormancy. In this study, sscd1 seeds displayed deep dormancy and hypersensitivity to the GA biosynthesis inhibitor paclobutrazol, but not to ABA during germination. However, exogenous GA₃ could not completely recover dormancy or germination of sscd1 seeds. Moreover, GA₃ level was reduced, which was consistent with the decreased expression of GA3-oxidase 1 in imbibed sscd1 seeds. Furthermore, SSCD1 acted upstream of RGA-LIKE 2. Eliminating the accumulation of Tyr metabolites by inhibiting homogentisate dioxygenase, an enzyme upstream of FAH, completely rescued the phenotype of sscd1 seeds. Additionally, germination of sscd1 seeds was hypersensitive to FAH deficiency-induced accumulation of succinylacetone, which is a Tyr metabolite. These findings suggest that FAH deficiency in sscd1 causes accumulation of Tyr metabolites, thereby disrupting GA biosynthesis and signaling. This resulted in deep dormancy and hypersensitivity to paclobutrazol during germination and highlights the important role of the Tyr degradation pathway in GA-mediated seed dormancy and germination. Full article