Search Results (63)

As a plant-specific peroxidase family, class III peroxidase (PRX) plays an important role in plant growth, development, and stress response. In this study, a preliminary functional analysis of CqPRX9L1 was conducted. Bioinformatics analysis revealed that CqPRX9L1 encodes a 349-amino acid protein belonging to the plant-peroxidase-like superfamily, featuring a transmembrane domain and cytoplasmic localization. The promoter region of CqPRX9L1 harbors various cis-acting elements associated with stress responses, hormone signaling, light regulation, and meristem-specific expression. The tissue-specific expression pattern of the CqPRX9L1 gene and its characteristics in response to different stresses were explored using subcellular localization, quantitative real-time PCR (qRT-PCR), and heterologous transformation into Arabidopsis thaliana. The results showed that CqPRX9L1, with a transmembrane structure, was localized in the cytoplasm, which encodes 349 amino acids and belongs to the plant-peroxisome-like superfamily. The promoter region contains stress-response elements, hormone-response elements, light-response elements, and meristem expression-related elements. The expression of CqPRX9L1 was relatively higher in ears and roots at the panicle stage than in stems and leaves. CqPRX9L1 showed a dynamic expression pattern of first decreasing and then increasing under abiotic stresses such as 15% PEG 6000, low temperature, and salt damage, with differences in response time and degree. CqPRX9L1 plays an important role in response to abiotic stress by affecting the activity of antioxidant enzymes such as superoxide dismutase (SOD) and peroxidase (POD), as well as the synthesis and decomposition of proline (Pro). CqPRX9L1 also affects plant bolting and flowering by regulating key flowering genes (such as FT and AP1) and gibberellin (GA)-related pathways. The results establish a foundation for revealing the functions and molecular mechanisms of the CqPRX9L1 gene. Full article

The floral transition in Chinese cabbage (Brassica rapa ssp. pekinensis) is governed by a complex interplay of gene expression and hormonal regulation. Temporal transcriptome profiling was conducted across three developmental stages: pre-bolting (PBS), bolting (BS), and flowering stages (FS), to investigate the underlying molecular mechanisms. A total of 7092 differentially expressed genes (DEGs) were identified, exhibiting distinct expression trajectories during the transition. Moreover, functional enrichment analyses revealed strong associations with plant hormone signaling, MAPK pathways, and developmental regulation processes. Key flowering-related genes, such as BrFLM, BrAP2, BrFD, BrFT, and BrSOC1s displayed antagonistic expression patterns. Hormonal pathways involving auxin, ABA, ET, BR, GA, JA, CK, and SA showed stage-dependent modulation. Further, orphan genes (OGs), especially EARLY FLOWERING 1 (EF1), showed significant upregulation during the transition, which exhibited 1.84-fold and 1.93-fold increases at BS and FS compared to PBS, respectively (p < 0.05). Functional validation through EF1 overexpression (EF1OE) in Arabidopsis consistently promoted early flowering. The expression levels of AtFT and AtSOC1 were significantly upregulated in EF1OE lines compared to wild-type (WT) plants. The findings contribute to understanding the coordinated genetic and hormonal events driving floral development in Chinese cabbage, suggesting EF1 as a candidate for bolting resistance breeding. This work also expands the existing regulatory framework through the successful integration of OGs into the complex floral induction system of Brassica crops. Full article

Orphan genes (OGs), which are unique to a specific taxon and have no detectable sequence homology to any known genes across other species, play a pivotal role in governing species-specific phenotypic traits and adaptive evolution. In this study, 20 OGs of Chinese cabbage (Brassica rapa OGs, BrOGs) were transferred into Arabidopsis thaliana by genetic transformation to construct an overexpression library in which 50% of the transgenic lines had a delayed flowering phenotype, 15% had an early flowering phenotype, and 35% showed no difference in flowering time compared to control plants. There were many other phenotypes attached to these transgenic lines, such as leaf color, number of rosette leaves, and silique length. To understand the impact of BrOGs on delayed flowering, BrOG142OE, which showed the most significantly delayed flowering phenotype, was chosen for further analysis, and BrOG142 was renamed BOLTING RESISTANCE 4 (BR4). In BR4OE, the expression of key flowering genes, including AtFT and AtSOC1, significantly decreased, and AtFLC and AtFRI expression increased. GUS staining revealed BR4 promoter activity mainly in the roots, flower buds and leaves. qRT-PCR showed that BR4 primarily functions in the flowers, flower buds, and leaves of Chinese cabbage. BR4 is a protein localized in the nucleus, cytoplasm, and cell membrane. The accelerated flowering time phenotype of BR4OE was observed under gibberellin and vernalization treatments, indicating that BR4 regulates flowering time in response to these treatments. These results provide a foundation for elucidating the mechanism by which OGs regulate delayed flowering and have significance for the further screening of bolting-resistant Chinese cabbage varieties. Full article

The degeneration of germplasm is a key factor limiting the yield and quality of Gastrodia elata Blume. Sexual reproduction is a primary method to address this degeneration, while the number of flowers and capsules is directly related to sexual reproduction. However, the genetic mechanisms underlying the high flower/fruit-bearing traits in G. elata remain unclear. We first compared the quantitative and qualitative traits during the flowering to fruiting period of G. elata, including bolting height, flowering quantity, flowering time, fruiting quantity, capsule spacing, seed quality, etc. The natural materials were selected by multi-capsule and few-capsule for transcriptome analysis to screen the differentially expressed genes (DEGs); the candidate gene GePIF4 was suspected to regulate the formation of multiple flowers and fruits. It was confirmed that GePIF4 has multiple biological functions in the overexpression of transgenic lines, including increasing numbers of vegetative propagation corms (VPCs) and promoting the growth of G. elata. Through comparative transcriptomic analysis of EV and OE-GePIF4 transgenic lines, the transcriptional regulatory network of GePIF4 was identified, and transient expression of GePIF4 was demonstrated to significantly promote gastrodin accumulation. The dual-LUC assay and in vitro yeast one hybrid results showed that GePIF4 could directly bind to GeRAX2 to regulate multi-capsule formation, and GePIF4 could directly bind to GeC4H1 to promote gastrodin accumulation. Therefore, we elucidate the role of GePIF4 in multi-capsule formation and secondary metabolite accumulation, thereby laying the groundwork for the genetic improvement of G. elata germplasm resources. Full article

Globe artichoke [Cynara cardunculus var. scolymus (L.)] is a perennial composite cultivated for its immature inflorescences. Over time, the market for growers has steadily shifted away from vegetatively propagated varieties and towards seed-propagated hybrids. Since the latter tend to produce relatively late in the season, advancing the moment of flowering remains a major objective for breeders, who can benefit from insight gained into the genetic architecture of this trait. In plants, the timing of flowering is strongly regulated at the genetic level to ensure reproductive success. Genetic studies in model and non-model species have identified gene families playing crucial roles in flowering time control. One of these is the phosphatidylethanolamine-binding protein (PEBP) family, a conserved group of genes that, in plants, not only regulate the vegetative-to-reproductive phase transition, but also the development of inflorescences. In this work, we identified seven PEBP family members in the globe artichoke genome, belonging to three major clades: MOTHER OF FT AND TFL1 (MFT)-like, TERMINAL FLOWER 1 (TFL1)-like, and FLOWERING LOCUS T (FT)-like. Our results further show that CcFT expression is upregulated after the floral transition and partially complements the ft-10 mutant, whilst CcTFL1 is expressed in the shoot apex and developing inflorescences and complements the tfl1-1 mutant. These results suggest that the flowering-suppressing function of CcTFL1 is conserved in globe artichoke whereas conservation of the floral promoting function of CcFT remains uncertain. Full article

The globular buds and stems are the main edible organs of broccoli. Bolting is an important agronomic trait, and the timing of its occurrence is particularly critical when breeding and domesticating broccoli. The molecular mechanism that regulates broccoli bolting time is not well-understood. In this study, the apical flower bud and leaf tissues of two broccoli varieties with different bolting intensities were selected for metabolome and transcriptome analyses. In the apical flower buds of early-bolting B2554 and late-bolting B2557, 1094 differentially expressed genes and 206 differentially accumulated metabolites were identified. In the leaves, 487 differentially expressed genes and 40 differentially accumulated metabolites were identified. In the floral pathway, the expression of FLC (FLOWERING LOCUS C) was significantly upregulated, and that of FT (FLOWERING LOCUS T) was significantly downregulated in the late-bolting plants, indicating their possible role in suppressing bolting. In addition, significant differences were identified in the sucrose synthesis and transport, hormone synthesis, and signal transduction processes in early-bolting B2554 and late-bolting B2557. Sucrose accumulation in the leaves and apical flower buds of the early-bolting plants was about 1.3 times higher than in the late-bolting plants. Indole-3-acetic acid (IAA) and abscisic acid (ABA) accumulation in the apical flower buds of the late-bolting plants was more than twice that in the early-bolting plants. Jasmonic acid (JA) accumulation in the apical flower buds of the late-bolting plants was more than ten times higher than in the early-bolting plants. Phenolic acids may affect the bolting time of broccoli. This study offers new insights into the regulation mechanism of broccoli bolting and provides some potential molecular targets to include in breeding methods that regulate bolting time. Full article

Chinese cabbage (Brassica rapa L. ssp. pekinensis) is a key vegetable crop in Asia, but its commercial value is often reduced by premature flowering triggered by vernalization. The molecular mechanisms behind this process are not fully understood. MADS-box genes, as crucial transcriptional regulators, play vital roles in plant development, including flowering. In this study, 102 MADS-box genes were identified in Chinese cabbage through bioinformatics analyses, covering phylogeny, chromosomal localization, and gene structure. Real-time quantitative PCR and RNA-seq data analysis revealed that the expression level of AGL27 declined as vernalization time increased. To determine BrAGL27′s functions, we obtained BrAGL27-overexpressed (OE) Arabidopsis thaliana lines that showed significantly later flowering compared with the wild type (WT). The expression levels of flowering suppressor genes AtFLC and AtTEM1 were significantly high-regulated in the BrAGL27-OE lines compared to WT plants, while the expression levels of the floral genes AtSPL15, AtSOC1, AtFT, and AtAP3 were significantly lower in the BrAGL27-overexpressed lines than in the wild type. These findings enhance understanding of MADS-box genes in vernalization and flowering regulation, offering a basis for further research on bolting resistance and flowering control in Chinese cabbage. Full article

Understanding the complex mechanisms underlying sex differentiation in dioecious plants is fundamental to elucidating plant reproductive strategies and their adaptive responses to environmental stresses. Pistacia chinensis, previously considered a strictly dioecious species, has been found to exhibit monoecy, with sex differentiation closely linked to environmental stress during floral development. However, the underlying molecular mechanisms remain poorly understood. This study explores the influence of environmental stress on sex differentiation with a focus on heat shock proteins (Hsps). Biochemical analyses revealed higher proline content and SOD activity in dioecious and monoecious females compared to males during the sex differentiation phase. Two key genes, PcHsp70-1 and PcHsp90, were identified as differentially expressed between sexes. Subcellular localization analysis showed that these proteins are present in both the nucleus and cytoplasm. Overexpression of PcHsp70-1 in Arabidopsis promoted bolting and flowering by upregulating flowering-related genes and also enhanced drought resistance. Similarly, PcHsp90 contributed to drought tolerance through multiple mechanisms. These findings suggest that Hsps play a key role in linking environmental stress responses to sex differentiation, thus laying the foundation for further research on plant–environment interactions and stress-adaptive mechanisms in P. chinensis. Full article

Plants exhibit diverse pathways to regulate the timing of flowering. Some plant species require a vegetative phase before being able to perceive cold stimuli for the acceleration of flowering through vernalization. This research confirms the correlation between the vernalization process and seedling age in Welsh onions. Findings from two vernalization experiments conducted at different time intervals demonstrate that seedlings must reach a vegetative phase of at least 8 weeks to consistently respond to vernalization. Notably, 8–week–old seedlings subjected to 6 weeks of vernalization displayed the shortest time to bolting, with an average duration of 138.1 days. Transcriptome analysis led to the identification of genes homologous to those in Arabidopsis thaliana that regulate flowering. Specifically, AfisC7G05578 (CO), AfisC2G05881 (AP1), AfisC1G07745 (FT), AfisC1G06473 (RAP2.7), and AfisC2G01843 (VIM1) were identified and suggested to have potential significance in age–dependent vernalization in Welsh onions. This study not only presents a rapid vernalization method for Welsh onions but also provides a molecular foundation for understanding the interplay between seedling age and vernalization. Full article

Bolting time is a critical trait that affects crop yield, adaptability, and overall productivity, making its regulation vital for agricultural success. In this study, we explored the genetic mechanisms controlling flowering time in radish (Raphanus sativus) via a combination of quantitative trait locus (QTL) analysis and genome-wide association study (GWAS). By developing an F₂ population from a cross between the relatively late-bolting variety ‘L432’ and the early-bolting variety ‘L285’, we identified 12 QTLs associated with bolting time. Furthermore, a GWAS performed on 60 East Asian radish accessions revealed 14 candidate genes potentially involved in flowering and bolting regulation. FLOWERING LOCUS C (FLC2) was the major candidate gene explaining the early and late bolting types. One locus was commonly detected from QTL and GWAS on chromosome 4, where CONSTANS-like (COL4) is located. To validate these findings, SNP markers were designed and applied to F₂ populations, revealing a correlation between marker presence and bolting phenotypes. These results offer valuable insights into the molecular control of bolting time in radish and identify candidate genes for use in marker-assisted breeding. These findings could enhance breeding efforts for optimizing bolting time in various radish markets. Full article

We assessed the flowering Chinese cabbage (Brassica rapa var. parachinensis), a specialty vegetable found in southern China. The sugar content of the stem tip is closely related to bolting and flowering. Sugar Will Eventually be Exported Transporters (SWEETs) are bidirectional sugar transporter proteins involved in numerous plant growth and development processes. The expression of BraSWEET12 is positively correlated with sugar content. However, it is unclear whether BraSWEET12 is involved in bolting and flowering. In this study, we identified and characterized BraSWEET12. BraSWEET12 in flowering Chinese cabbage contains 288 amino acids and is located on the cell membrane as a sucrose transporter protein. BraSWEET12 is highly expressed in the petals and stem tips of flowering Chinese cabbage and is upregulated by gibberellin and low temperatures. Overexpression of BraSWEET12 in Arabidopsis can increase sucrose content at the stem tip, upregulate the expression of AtAP1 and AtLFY, and advance the flowering time. Subsequently, our results indicate that BraSWEET12 is involved in sucrose accumulation at the stem tip of flowering Chinese cabbage and plays a crucial role in flowering regulation. These results provide a reference for elucidating the regulatory mechanisms underlying flowering Chinese cabbage bolting and flowering. Full article

Biostimulants are a new category of materials that improve crop productivity by maximizing their natural abilities. Out of these biostimulants, those that increase seed production are considered to be particularly important as they contribute directly to the increase in the yield of cereals and legumes. Ergothioneine (EGT) is a natural, non-protein amino acid with antioxidant effects that is used in pharmaceuticals, cosmetics, and foods. However, EGT has not been used in agriculture. This study investigated the effect of EGT on seed productivity in Arabidopsis thaliana. Compared with an untreated control, the application of EGT increased the seed yield by 66%. However, EGT had no effect on seed yield when applied during or after bolting and did not promote the growth of vegetative organs. On the other hand, both the number of flowers and the transcript levels of FLOWERING LOCUS T (FT), a key gene involved in flowering, were increased significantly by the application of EGT. The results suggest that EGT improves seed productivity by increasing flower number through the physiological effects of the FT protein. Furthermore, the beneficial effect of EGT on flower number is expected to make it a potentially useful biostimulant not only in crops where seeds are harvested, but also in horticultural crops such as ornamental flowering plants, fruits, vegetables. Full article

Angelica dahurica var. formosana (ADF), which belongs to the Umbelliferae family, is one of the original plants of herbal raw material Angelicae Dahuricae Radix. ADF roots represent an enormous biomass resource convertible for disease treatment and bioproducts. But, early bolting of ADF resulted in lignification and a decrease in the coumarin content in the root, and roots lignification restricts its coumarin for commercial utility. Although there have been attempts to regulate the synthesis ratio of lignin and coumarin through biotechnology to increase the coumarin content in ADF and further enhance its commercial value, optimizing the biosynthesis of lignin and coumarin remains challenging. Based on gene expression analysis and phylogenetic tree profiling, AdNAC20 as the target for genetic engineering of lignin and coumarin biosynthesis in ADF was selected in this study. Early-bolting ADF had significantly greater degrees of root lignification and lower coumarin contents than that of the normal plants. In this study, overexpression of AdNAC20 gene plants were created using transgenic technology, while independent homozygous transgenic lines with precise site mutation of AdNAC20 were created using CRISPR/Cas9 technology. The overexpressing transgenic ADF plants showed a 9.28% decrease in total coumarin content and a significant 12.28% increase in lignin content, while knockout mutant plants showed a 16.3% increase in total coumarin content and a 33.48% decrease in lignin content. Furthermore, 29,671 differentially expressed genes (DEGs) were obtained by comparative transcriptomics of OE-NAC20, KO-NAC20, and WT of ADF. A schematic diagram of the gene network interacting with AdNAC20 during the early-bolting process of ADF was constructed by DEG analysis. AdNAC20 was predicted to directly regulate the transcription of several genes with SNBE-like motifs in their promoter, such as MYB46, C3H, and CCoAOMT. In this study, AdNAC20 was shown to play a dual pathway function that positively enhanced lignin formation but negatively controlled coumarin formation. And the heterologous expression of the AdNAC20 gene at Arabidopsis thaliana proved that the AdNAC20 gene also plays an important role in the process of bolting and flowering. Full article

Bolting and flowering of vegetables are induced by vernalization in their early growth stage. This phenomenon is called premature bolting, and it has caused massive losses in production of vegetables such as cabbage, celery, carrot, radish, and spinach, etc. This review aimed to summarize studies on bolting and flowering pathways, physiological and biochemical changes, and underlined molecular mechanisms of various vegetable crop bolting involving genome and transcriptome analysis, and its association with vegetable breeding. This review could provide basic knowledge to carry out research on vegetable genetics and breeding and vegetable cultivation. Full article

Lettuce is susceptible to high-temperature stress during cultivation, leading to bolting and affecting yield. Plant-specific transcription factors, known as GRAS proteins, play a crucial role in regulating plant growth, development, and abiotic stress responses. In this study, the entire lettuce LsGRAS gene family was identified. The results show that 59 LsGRAS genes are unevenly distributed across the nine chromosomes. Additionally, all LsGRAS proteins showed 100% nuclear localization based on the predicted subcellular localization and were phylogenetically classified into nine conserved subfamilies. To investigate the expression profiles of these genes in lettuce, we analyzed the transcription levels of all 59 LsGRAS genes in the publicly available RNA-seq data under the high-temperature treatment conducted in the presence of exogenous melatonin. The findings indicate that the transcript levels of the LsGRAS13 gene were higher on days 6, 9, 15, 18, and 27 under the high-temperature (35/30 °C) treatment with melatonin than on the same treatment days without melatonin. The functional studies demonstrate that silencing LsGRAS13 accelerated bolting in lettuce. Furthermore, the paraffin sectioning results showed that flower bud differentiation in LsGRAS13-silenced plants occurred significantly faster than in control plants. In this study, the LsGRAS genes were annotated and analyzed, and the expression pattern of the LsGRAS gene following melatonin treatment under high-temperature conditions was explored. This exploration provides valuable information and identifies candidate genes associated with the response mechanism of lettuce plants high-temperature stress. Full article