Search Results (375)

Phototropins (PHOTs) are plant blue-light receptors that mediate crucial physiological processes such as phototropism, chloroplast movement, stomatal opening, and flowering. However, the PHOT family genes remain poorly characterized in pepper. Here, we identified and molecularly cloned two PHOT genes (CaPHOT1 and CaPHOT2) in pepper, which were phylogenetically classified into distinct groups with their homologs from rice, maize, tomato, and Arabidopsis. These genes exhibit conserved gene structures, implying functional conservation during evolution. Subcellular localization analysis confirmed that both CaPHOT1 and CaPHOT2 are localized to the plasma membrane. Expression profiling revealed that both CaPHOT1 and CaPHOT2 were expressed in all tissues, with the highest transcripts in leaves and the lowest in roots. Notably, RNA-seq data revealed that the expression of CaPHOT1 was up-regulated by JA and SA, whereas CaPHOT2 showed no significant changes. Furthermore, CaPHOT1 and CaPHOT2 displayed divergent expression patterns upon Phytophthora capsici infection (PCI). Furthermore, transient overexpression of CaPHOT1 in pepper enhanced susceptibility to PCI, indicating its negative role in disease resistance. Our findings identified the CaPHOT gene family in pepper and functionally demonstrated that CaPHOT1 negatively regulates resistance to PCI, thereby providing insights for future research on PHOTs in other plant species. Full article

Background/Objectives: Anthocyanins, water-soluble flavonoid pigments with critical roles in plant stress resistance, are not naturally accumulated in cultivated tomato (Solanum lycopersicum) due to an incomplete flavonoid metabolism pathway. In contrast, ‘Black Pearl’ tomato exhibits distinct peel color transitions (from indigo rose to deep purple–red) during ripening, making it an ideal model for investigating the regulatory mechanisms of anthocyanin synthesis. A comprehensive strategy was employed to elucidate these mechanisms, involving transcriptomic (Illumina HiSeq), metabolomic (UPLC-MS/MS), and functional analyses of the ‘Black Pearl’ tomato peel across four developmental stages: mature green (S1), coloring (S2), purple immature (S3), and fully ripened (S4). Results: Transcriptome profiling identified 597 core differentially expressed genes (DEGs) associated with anthocyanin accumulation. Temporal analysis indicated that structural genes and activators peaked at S3, whereas repressive MYBs, including SlMYB76 which peaked at S2, exhibited staged expression. In parallel, metabolomic analysis identified 36 metabolites, with cyanidin and pelargonidin derivatives being characterized as the principal pigments. Functionally, SlMYB76 was confirmed to be a negative regulator, as its transient overexpression reduced anthocyanin content and downregulated SlANS. Mechanistically, direct binding and repression of the SlANS promoter by SlMYB76 were confirmed through yeast one-hybrid and dual-luciferase assays. Furthermore, its physical interaction with the bHLH factor SlJAF13 in the nucleus was demonstrated by Y2H, BiFC, LCI, and Co-IP, supporting the formation of a repressive complex that co-regulates SlANS. Conclusions: A novel SlMYB76-SlJAF13-SlANS regulatory module controlling anthocyanin accumulation in the peel of ‘Black Pearl’ tomato was identified. This discovery enhances the current understanding of the tomato flavonoid regulatory network and provides strategic targets for the genetic improvement of fruit color and anthocyanin content through molecular breeding. Full article

Aroma is a crucial quality trait in ornamental flowers; however, the molecular mechanisms by which hormones regulate fragrance in Rhododendron remain poorly understood. In this study, Gibberellin (GA₃)-treated petals of Rhododendron fortunei Lindl were used as experimental materials to integrate volatile metabolomics with RNA-seq analysis, aiming to investigate aroma changes and their underlying molecular regulatory mechanisms. We cloned and characterized RfHMGR1, which encodes a key enzyme in the Mevalonate (MVA) pathway, and verified its function. Subcellular localization analysis showed that the Green Fluorescent Protein (GFP) signal of the RfHMGR1-GFP fusion protein was mainly distributed in the cytoplasm. Transient overexpression of RfHMGR1 in petals of two Rhododendron species (R. fortunei and Rhododendron hybrida) significantly increased the accumulation of the terpenoid linalool, whereas gene silencing reduced linalool accumulation. Furthermore, the purified recombinant RfHMGR1 protein exhibited HMGR-specific reductase activity in vitro. Our results confirmed that GA₃ regulates the terpenoid fragrance of R. fortunei by targeting the MVA pathway gene RfHMGR1. Collectively, these findings provide new insights into the fragrance regulation mechanisms in R. fortunei and identify molecular targets for breeding strategies aimed at improving floral scent. Full article

Endometrial cancer is one of the most common malignancies of the female reproductive system, with incidence rising globally due to population ageing and life-style-related risk factors. Calcium (Ca²⁺) is a ubiquitous second messenger regulating diverse physiological processes, and its dysregulation has been increasingly implicated in carcinogenesis, including endometrial. Altered expression and function of Ca²⁺ channels, pumps, exchangers, and binding proteins disrupt the finely tuned balance of Ca²⁺ influx, efflux, and intracellular storage, leading to aberrant signalling that promotes tumour proliferation, migration, survival, and metastasis. This review summarises current knowledge on the molecular “Ca²⁺ toolkit” in the human uterus, highlighting the role of voltage-gated calcium channels (VGCCs), transient receptor potential (TRP) channels, store-operated calcium entry (SOCE) components, Na⁺/Ca²⁺ exchangers, purinergic receptors, P-type ATPases (SERCA, SPCA, PMCA), ryanodine (RyR) and inositol 1,4,5-trisphosphate (IP₃R) receptors, and mitochondrial Ca²⁺ uniporter (MCU) complexes in endometrial cancer progression. Multiple Ca²⁺-handling proteins, including CACNA1D, CACNA2D1, TRPV4, TRPV1, TRPM4, MCU, and RyR1, exhibit cancer-associated overexpression or functional changes, correlating with poor prognosis and aggressive disease features. Emerging evidence supports the therapeutic potential of targeting Ca²⁺ homeostasis using small-molecule inhibitors, ion channel modulators or gene-silencing strategies. These interventions may restore Ca²⁺ balance, induce apoptosis or autophagy, and suppress metastatic behaviour. While no clinical trials have yet explicitly focused on Ca²⁺ modulation in endometrial cancer, the diversity of dysregulated Ca²⁺ pathways offers a rich landscape for novel therapeutic strategies. Targeting key components of the Ca²⁺ signalling network holds promise for improving outcomes in endometrial cancer. Full article

Ubiquitin-conjugating enzyme (UBC) plays a significant role in plant hormone signal transduction. In this study, we observed that TuMV infection markedly upregulates UBC mRNA expression, suggesting a close association between UBC and viral infection. Using Tobacco rattle virus (TRV)-based virus-induced gene silencing (VIGS) to downregulate UBC expression in Nicotiana benthamiana, we found that UBC-silenced plants exhibited enhanced susceptibility to TuMV compared with control plants. Conversely, transient overexpression of UBC protein suppressed viral propagation. Further analysis by reverse transcription quantitative PCR (RT-qPCR) revealed a substantial downregulation in the expression of SA and JA biosynthetic genes in UBC-silenced plants. Accordingly, liquid chromatography–tandem mass spectrometry (LC-MS/MS) confirmed a marked decrease in the accumulation of the corresponding hormones. Exogenous application of SA or JA partially restored antiviral resistance in UBC-silenced plants, indicating that hormonal deficiency contributes to enhanced viral susceptibility. Collectively, our results demonstrate that UBC positively regulates SA and JA biosynthesis. UBC silencing impairs both SA- and JA-mediated defense pathways, thereby facilitating viral infection in N. benthamiana. Full article

Background/Objectives: Transient neonatal diabetes mellitus (TNDM) is a form of neonatal diabetes mellitus (NDM) arising in the first weeks of life and remitting in infancy. Epigenetic aberrations at the imprinted 6q24 locus (overexpression of PLAGL1/HYMAI) are the most common causes of TNDM. The aim of this study was a retrospective clinical and genetic analysis of a Polish pediatric cohort, emphasizing the role of methylation-specific MLPA (MS-MLPA) in the diagnosis of TNDM. Methods: We conducted a retrospective analysis of the medical records of 22 patients with diabetes diagnosed at 1 year of age. The molecular studies included an analysis of the NDM gene panel by a targeted NGS and MS-MLPA for the 6q24 imprinting region. Results: 6q24-TNDM was confirmed in five patients, with a median age of diabetes remission of 4 months (IQR: 3–6 months). The MS-MLPA identified paternal UPD6 or isolated maternal hypomethylation of PLAGL1 in three patients, and two had a paternal 6q24 duplication. Conclusions: In our group, changes in the 6q24 region were confirmed in 22.7% of NDM patients, indicating the usefulness of the MS-MLPA technique in the diagnosis and detection of imprinting defects. We acknowledge key limitations, including diagnostic delays and incomplete parental testing, which precluded trio-based confirmation of paternal UPD6 versus epimutation in some cases; future diagnostic workflows should incorporate an early trio-based SNP array or STR confirmation. A methylation analysis should be included early in the NDM genetic diagnosis process to provide genetic counseling and monitor patients for diabetes recurrence. Full article

Vitamin B6 is an essential coenzyme involved in various metabolic processes critical for plant growth and development. However, its biosynthesis and regulatory mechanisms remain poorly understood in the ancient gymnosperm Ginkgo biloba. In this study, we identified two members of the PDX2 gene family (Gb_34755 and Gb_34990) through genome-wide analysis and characterized their molecular and functional properties. Bioinformatic analysis revealed distinct physicochemical traits and subcellular localizations, with Gb_34755 predicted in the cytoplasm and Gb_34990 in both chloroplasts and cytoplasm. Both proteins contain the glutaminase-related PLN02832 domain, indicating involvement in VB6 biosynthesis. Chromosomal mapping placed the genes in transcriptionally active regions on chromosomes 6 and 9. Phylogenetic analysis showed close evolutionary relationships between Ginkgo PDX2 genes and those in ferns and gymnosperms, distinct from angiosperms. Promoter analysis revealed differential enrichment of cis-elements: Gb_34990 harbored low-temperature and salicylic acid-responsive elements, while Gb_34755 showed motifs related to development. Gene expression profiling indicated significant upregulation (p < 0.05) of both genes during the late developmental stages of Ginkgo kernels, coinciding with peak VB6 content. Functional validation via transient overexpression in Nicotiana benthamiana confirmed a positive regulatory role, with VB6 levels increasing from 3.38 μg/g to 12.17 μg/g (p < 0.05). This study provides the first comprehensive functional analysis of the PDX2 gene family in Ginkgo and confirms their critical role in VB6 biosynthesis. These findings enhance our understanding of vitamin metabolism in gymnosperms and present promising targets for metabolic engineering in plants. Full article

Miscanthus, a perennial grass, is renowned for its remarkable tolerance to abiotic stress. Excessive levels of drought severely impair plant growth and yield. Plant nuclear factor Y (NF-Y) transcription factors (TFs) play pivotal roles in regulating responses to drought stress in species such as Arabidopsis and maize. However, their functional roles in conferring drought tolerance in Miscanthus remain largely unexplored. This study’s genome-wide analysis and gene expression profiling of Miscanthus under dehydration/osmotic stress identified a transcription factors gene, MsNF-YA4, which was significantly upregulated under dehydration/osmotic stress. MsNF-YA4 overexpression in Arabidopsis significantly enhanced drought tolerance, leading to increased transcription of stress- and antioxidant enzyme-related genes. Compared with the wild type (WT), the transgenic lines exhibited markedly higher relative water content (RWC), chlorophyll content, proline level, and antioxidant enzyme activity. Furthermore, the MsNF-YA4/MsNF-YB3/MsNF-YC2 improved the transactivation of the Miscanthus P5CS1, SOD (Cu/Zn) and CAT1 promoters in the transient system. These results offer fresh perspectives on the role of Miscanthus NF-YAs in drought tolerance and offer promising genetic resources for developing drought-tolerant crops through breeding programs. Full article

Ascorbate oxidases (AAOs) are key regulators of extracellular redox homeostasis and plant stress responses, but their roles in grapevine defense remain unclear. Here, we performed a genome-wide analysis and characterization of the AAO gene family in grapevine Vitis amurensis, identifying 10 VaAAO genes that are unevenly distributed across six chromosomes, with notable clustering on chromosome 7. Promoter analysis revealed multiple phytohormone- and stress-responsive cis-elements (e.g., ARE, STRE, and TCA-element) and transcription factor binding sites (e.g., MYC/MYB, and WRKY), suggesting involvement in redox- and stress-related signaling pathways. Analysis of previously published transcriptomic data under Botrytis cinerea infection identified VaAAO7 as a key pathogen-responsive gene. VaAAO7 was rapidly induced by H₂O₂, and its transient ectopic overexpression in susceptible V. vinifera ‘Red Globe’ leaves significantly reduced lesion development. Together, these results demonstrate that VaAAO7 functions as a positive regulator of B. cinerea resistance and highlight its potential for genetic engineering to enhance systemic defense and develop disease-resistant grapevine cultivars. Full article

This study investigated the phylogenetic relationships in the pear calcium-dependent protein kinase (CDPK) pan-gene family and elucidated its role in the resistance to scab disease caused by Venturia nashicola. By integrating data from eight genomic sets from five cultivated pear species, Pyrus bretschneideri, P. ussuriensis, P. sinkiangensis, P pyrifolia, and P. communis, along with P. betulifolia and interspecific hybrids, 63 PyCDPK family members were identified. Among these, P. communis possessed the highest number of CDPK genes, whereas P. bretschneiderilia had the fewest. These genes encode proteins ranging from 459 to 810 amino acids in length, and are predominantly localized to the cell membrane. Six genes, PyCDPK9, PyCDPK11, PyCDPK12, PyCDPK14, PyCDPK16, and PyCDPK19, were classified as core members of the pan-genome, and PyCDPK19 showed evidence of positive selection pressure. Clustering analysis and transcriptomic expression profiling of disease-resistance-related CDPKs identified PyCDPK19 as a key candidate associated with scab resistance. Promoter analysis revealed that the regulatory region of PyCDPK19 contains multiple cis-acting elements involved in defense responses and methyl jasmonate signaling. Transient overexpression of PyCDPK19 in tobacco leaves induced hypersensitive cell necrosis, accompanied by significant increases in hydrogen peroxide (H₂O₂) accumulation and malondialdehyde (MDA) content. Similarly, overexpression in pear fruit callus tissue followed by pathogen inoculation resulted in elevated levels of both H₂O₂ and MDA. Collectively, these findings indicate that PyCDPK19 mediates defense responses through the activation of the reactive oxygen species pathway in both tobacco and pear plants, providing a promising genetic target for enhancing scab resistance in pears. Full article

Plant growth regulators Gibberellin A3 (GA₃) and N-(2-chloro-4-pyridyl)-N′-phenylurea (CPPU) are widely used in ‘Shine Muscat’ cultivation to regulate berry shape and size. However, the molecular mechanisms underlying their regulation of berry shape remain poorly understood. This study was designed to elucidate the cytological processes and molecular basis through which GA₃ and CPPU modulate berry morphology in ‘Shine Muscat’. The results showed that spraying GA₃ or CPPU alone increases the hormone levels of endogenous auxin (IAA) and GA₃ and reduces the levels of endogenous 6-benzyladenine (6-BA). GA₃ treatment resulted in the number of cells per unit area being significantly reduced and the cell transverse and longitudinal diameters being significantly increased. CPPU treatment increases the number of cells per unit area, cell transverse and longitudinal diameters. In the results of CKvsG2 and CKvsC2 transcriptome sequencing, 2793 and 1082 differentially expressed genes (DEGs) were identified, respectively. These DEGs are significantly enriched in Gene Ontology (GO) terms related to plant hormones; the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the zeatin biosynthesis pathway (ko03030) is significantly enriched. The Arabidopsis response regulator (ARR) is down-regulated in response to GA₃ application and up-regulated in response to CPPU application. Transient overexpression of VvARR (OE-VvARR) in ‘Shine Muscat’ berry increased the number of berry cells and cell transverse and longitudinal diameters. Furthermore, virus-induced gene silencing of VvARR (VIGS-VvARR) reduced the number of berry cells but increased cell transverse and longitudinal diameters. The OE-VvARR grape hormone levels of endogenous GA₃, 6-BA, and IAA were significantly increased. In VIGS-VvARR grape, the levels of endogenous IAA and 6-BA are significantly increased, but there is no significant difference in endogenous GA₃. These findings offer novel insights into the molecular mechanisms by which GA₃ and CPPU govern berry development, corroborating the hypothesis that VvARR acts as a pivotal regulator mediating the effects of these plant growth regulators on berry cell morphology and, consequently, berry shape. Full article

Taraxacum kok-saghyz Rodin, an important rubber-producing plant, has emerged as a potential alternative crop for the natural rubber industry. Geranyl diphosphate synthase (GDS) catalyzes the condensation of dimethylallyl pyrophosphate and isopentenyl pyrophosphate into geranyl pyrophosphate in the mevalonate pathway in plants. However, its specific functions in natural rubber biosynthesis in T. kok-saghyz remain unclear. Methods: We conducted genome-wide analyses of TkGDS genes, followed by transient transformation assay, expression profiling, natural rubber quantification, and analysis of T. kok-saghyz photosynthesis. Results: Seven TkGDS genes are located on chromosomes A6 and A7 with an uneven distribution. All encoded TkGDS proteins contain FARM and SARM motifs. TkGDS1, TkGDS2, and TkGDS7 possess lspA domains, while TkGDS3, TkGDS4, TkGDS5, and TkGDS6 contain PLN02890 domains; both subgroups share similar domain architecture. TkGDS1, TkGDS2, and TkGDS7 exhibit interspecies collinearity with Arabidopsis thaliana; no intraspecies collinearity was detected. The putative cis-acting elements in promoter region of TkGDS genes mainly comprised abscisic acid responsiveness, anaerobic induction, light responsiveness, and MeJA responsiveness. Transient expression assays confirmed chloroplast localization of all TkGDS proteins. A strong positive correlation was observed between TkGDS1/TkGDS7 expression and natural rubber content, as confirmed by both transcriptome and qPCR analyses in T. kok-saghyz lines. Furthermore, overexpression of TkGDS1 and TkGDS7 improved photosynthetic efficiency and significantly increased natural rubber content (OE-TkGDS1: 6.08 ± 0.16%; OE-TkGDS7: 5.62 ± 0.32%; WT: 4.76 ± 0.28%). Conclusions: Our study elucidates the role of GDS1 and GDS7 in promoting growth and latex content, offering a genetic strategy for enhancing rubber accumulation in T. kok-saghyz. Full article

Background/Objectives: Hepatoblastoma (HB), the most common pediatric liver cancer, often bears mutations in and/or otherwise deregulates the oncogenic transcription factors β-catenin (B), YAP (Y) and NRF2 (N). HB research is hampered by a paucity of established cell lines, particularly those possessing these molecular drivers. All combinations of B, Y and N (BY, BN, YN and BYN) are tumorigenic when overexpressed in murine livers, but it has not been possible to establish cell lines from primary tumors. Recently, we found that concurrent, in vivo Crispr-mediated targeting of the Cdkn2a tumor suppressor locus allows for immortalized cell lines to be efficiently generated. Methods: We derived and characterized five immortalized cell lines from Cdkn2a-targeted BN and YN HBs. Results: Four of the above five cell lines retained their ability to grow as subcutaneous or “pseudo-metastatic” pulmonary tumors in the immunocompetent mice from which they originated. Most notably, when maintained under hypoxic conditions for as little as 2 days, BN cells transiently upregulated the expression of numerous endothelial cell (EC)-specific genes and acquired EC-like properties that benefited tumor growth. These lines and those from previously derived BY and BYN HBs also possessed similar sensitivities to four commonly employed chemotherapeutic drugs. Conclusions: The above-described approach is currently the only means to generate HB cell lines with pre-selected and clinically relevant oncogenic drivers. Its generic nature should also allow bespoke HB cell lines with other oncogenic drivers to be readily produced. A collection of such cell lines will be useful for studying tumor cell-to-EC trans-differentiation, interactions with the immune environment and drug sensitivities. Full article

Glycerol-3-phosphate acyltransferases (GPATs) catalyze the initial and rate-limiting step of glycerolipid biosynthesis, yet their contribution to salt tolerance in the soybean (Glycine max (L.) Merr.) plants remains largely uncharacterized. In this study, a total of 27 GmGPAT genes were identified, and their evolutionary relationships, chromosomal distribution, conserved motifs, and cis-regulatory elements were comprehensively analyzed. Through transcriptomic and qPCR analyses, many GmGPATs were found to be predominantly expressed in roots, with GmGPAT1, a plastid-targeted isoform, displaying the most rapid and pronounced transcriptional activation under salt stress. GFP-fusion experiments in transient expression assays confirmed plastid localization of GmGPAT1. Heterologous expression in Escherichia coli together with enzyme kinetics analyses validated its enzymatic function as a GPAT family member. The soybean hairy-root lines overexpressing GmGPAT1 exhibited enhanced root elongation, increased biomass, and improved photosynthetic efficiency under 120 mM NaCl stress, while CRISPR/Cas9 knockout mutants showed pronounced growth inhibition. Physiological assays demonstrated that GmGPAT1 overexpression mitigated oxidative damage by limiting reactive oxygen species (ROS) accumulation and lipid peroxidation, increasing antioxidant enzyme activities (CAT, SOD, POD), and elevating the ratios of AsA/DHA and GSH/GSSG. These changes contributed to redox homeostasis and improved Na⁺ extrusion capacity. A genome-wide association study (GWAS) involving 288 soybean accessions identified a single nucleotide polymorphism in the GmGPAT1 promoter that was significantly correlated with salt tolerance, and the beneficial Hap1 allele emerged as a promising molecular marker for breeding. Together, these analyses emphasize the status of GmGPAT1 as a major regulator of salt stress adaptation through the coordinated modulation of lipid metabolism and redox balance, extend the functional annotation of the soybean GPAT family, and highlight new genetic resources that can be leveraged to enhance tolerance to salt stress in soybean cultivars. Full article

Rosa roxburghii Tratt., a fruit crop known for its high Vitamin C content and other nutritional compounds, has not yet been studied for its auxin response factor (ARF) family members. ARFs are important proteins in auxin-mediated pathways, playing a vital role in plant physiological and biochemical processes such as plant development, and flower and fruit maturation. In the present study, we identified 14 ARF genes (designated as RrARFs) in R. roxburghii, which are distributed across seven chromosomes and grouped into four subfamilies. An analysis of cis-acting elements revealed that these genes might be involved in various biological processes, including plant development, flower development, light responses, cell cycle regulation, phytohormone responses, and responses to abiotic and biotic stresses. A gene expression analysis demonstrated differential expression of RrARF genes across different tissues and stages of fruit development, with four members showing higher expression during the fruit ripening stages. Furthermore, a coexpression analysis identified that RrARF5 was highly coexpressed with RrMDHAR1, a key enzyme involved in Vitamin C biosynthesis. Moreover, transactivation assays and transient overexpression experiments confirmed that RrARF5 activates the transcription of RrMDHAR1. The findings of this study suggest a potential role of the ARF gene family in Vitamin C accumulation in R. roxburghii and enhance our understanding of the diverse regulatory function of the ARF gene family in plants. Full article