Cauliflower curd color influences nutritional quality and consumer preference. Using non-targeted metabolomics, we profiled four cultivars (white, green, yellow, gold). White curds accumulated more soluble sugars, while colored curds showed elevated tricarboxylic acid (TCA) cycle intermediates and secondary metabolites. Green curds were enriched for chlorophyll-associated amino acids, sulforaphane and gamma-aminobutyric acid (GABA), whereas yellow/gold curds accumulated more flavonoids and phenolic acids. These metabolic differences were linked to enhanced antioxidant potential and flavor diversity. This hypothesis-generating study provides a metabolic basis for breeding nutritionally enhanced cauliflower varieties.

Broccoli (Brassica oleracea L.) sprouts have been popular among consumers for its excellent nutritional value. Glucosinolates (GSLs) and their degradation products, which are abundant in cruciferous vegetables, are linked to the anticancer activity. This study investigated the GSLs and derivatives accumulation characteristic in different broccoli sprout varieties and identified two GSLs rich varieties, B001 and B003. Transcriptome analysis indicated that BoMYB34-3 contributed to the high GSLs content in B001. Overexpressing BoMYB34-3 in broccoli cotyledons significantly increased GSLs and derivatives levels. Nuclear-localised BoMYB34-3 bound to the promoters of GSLs biosynthesis genes and activated their expression to promote GSLs accumulation. An OVATE family protein 6 (BoOFP6) was identified as an interacting partner of BoMYB34-3. Overexpressing BoOFP6 significantly suppressed GSLs accumulation and the expression level of related genes, whereas its silencing markedly promoted these processes. BoOFP6 exerted its negative regulatory function by mediating the re-localisation of BoMYB34-3 to the cytoplasm rather than by directly inhibiting GSLs biosynthesis related genes. This regulatory process could be influenced by environmental cues, including blue light, mechanical damage, salt stress and drought stress. This study provides insights into GSLs biosynthetic pathway and a foundation for breeding strategies to enhance health-promoting compounds in broccoli sprouts.

VrANR and VrMYB90 were identified by transcriptome between ‘Sulv1’ and ‘M0313’. VrMYB90 acted upstream of VrANR by binding to the promoter of VrANR and inhibiting the expression of VrANR, thus regulating negatively the biosynthesis of proanthocyanins. Anthocyanin reductase (ANR), the enzyme responsible for converting anthocyanidins to their corresponding 2,3-cis-flavan-3-ols, which is crucial to balance the anthocyanins and proanthocyanidins (PAs) level. In this study, significant differences were observed in the contents of anthocyanins and PA between the two cultivars. We identified a structural gene VrANR and a MYB transcription factor VrMYB90 that acts upstream of VrANR based on transcriptomic data analysis. Both of the two factors played key roles in PA accumulation in mung bean. Overexpressing VrANR in mung bean hairy roots led to a higher PA accumulation when compared with empty vector. Furthermore, overexpression VrANR in the Arabidopsis ban (anr) mutants increased PA content while reducing anthocyanin levels. Yeast-one-hybridization, β-glucuronidase (GUS) assay and dual-luciferase (LUC) reporter assays revealed that VrMYB90 (a positive regulator in anthocyanin) could bind to the VrANR promoter to repress its expression and then repress PA synthesis. Determination of transcript level of VrANR in VrMYB90 transgenic mung bean also proved that VrMYB90 inhibited the expression of VrANR. Above all, our present results suggested that VrMYB90 can repress the transcription of VrANR to play a negative role in the PAs accumulation in mung bean. These findings enriched our understanding in the regulatory network of PAs in mung bean.

Anthocyanin biosynthesis in plants is influenced by a wide range of environmental factors, such as light, temperature and nutrient availability. In this study, we revealed that the potassium-repressed anthocyanin accumulation in radish hypocotyls was associated with altered sugar distribution and sugar signaling pathways rather than changes in oxidative stress status. Sugar-feeding experiments suggested a hexokinase-independent glucose signal acted as a major contributor in regulating anthocyanin biosynthesis, transport and regulatory genes at the transcriptional level. Several R2R3-MYBs were identified as anthocyanin-related MYBs. Phylogenetic and protein sequence analyses suggested that RsMYB75 met the criteria of subgroup 6 MYB activator, while RsMYB39 and RsMYB82 seemed to be a non-canonical MYB anthocyanin activator and repressor, respectively. Through yeast-one-hybrid, dual-luciferase and transient expression assays, we confirmed that RsMYB39 strongly induced the promoter activity of anthocyanin transport-related gene RsGSTF12, while RsMYB82 significantly reduced anthocyanin biosynthesis gene RsANS1 expression. Molecular models are proposed in the discussion, allowing speculation on how these novel RsMYBs may regulate the expression levels of anthocyanin-related structural genes. Together, our data evidenced the strong impacts of potassium on sugar metabolism and signaling and its regulation of anthocyanin accumulation through different sugar signals and R2R3-MYBs in a hierarchical regulatory system.

Red radish sprout become a popular dietary vegetable because of its unique flavor, abundant nutrients and short production cycle. As a cruciferous plant, it has strong ability to absorb and assimilate Se which can promote the content of anthocyanin in plants. However, the mechanisms of Se on anthocyanin accumulation are still unclear. In this study, we explored that appropriate Se promoted growth, antioxidant system and nutrients in radish sprouts. The enhancement of photosynthesis by Se treatment resulted in more sucrose synthesis in radish sprouts. And the transport of sucrose from cotyledon to hypocotyl promoted by Se through up-regulating the gene expression of sucrose transporters, and more sucrose increased the expression of anthocyanin biosynthesis genes to promote anthocyanin accumulation in hypocotyl. These results reveal the beneficial effect of Se on radish sprouts quality, and provide a new insight into the function of Se on sucrose-induced anthocyanin accumulation in radish sprouts.

Mung bean is an important grain-legume crop and its sprout is an economical and nutrient vegetable for the public, but the genetic regulation of anthocyanin production, which is an antioxidant in mung bean, remains elusive. In our study, we characterized a subgroup (SG) 6 R2R3-MYB anthocyanin activator VrMYB90 and a SG 4 R2R3-MYB anthocyanin repressor VrMYB3, which synergistically function in regulating anthocyanin synthesis with VrbHLHA transcription factor. The overexpressed VrMYB90 protein activates the expression of VrMYB3 and VrbHLHA in mung bean hair roots, and also promotes VrDFR and VrANS transcript levels by directly binding to the corresponding promoters at specific motifs (CAACTG and CCGTTG). VrMYB90 interacts with VrbHLHA to enhance its regulatory activities on VrDFR and VrANS. Furthermore, the interaction between VrMYB3 with VrMYB90 and VrbHLHA could result in the restriction of anthocyanin synthesis to prevent excessive anthocyanin accumulation. Our results demonstrate that the VrMYB90 protein, in conjunction with VrMYB3 and VrbHLHA, forms a key regulatory module to fine-tune anthocyanin synthesis in mung bean.

Lysine, the first limiting essential amino acid, the deficiency of which seriously affects the health of human and animals. In this study, quinoa germination significantly increased the nutrients, especially lysine content. To better understanding the underlying molecular mechanism of lysine biosynthesis, isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics, RNA-sequencing (RNA-Seq) technology and liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) platform-based phytohormones analyses were conducted. Through proteome analyses, a total of 11,406 differentially expressed proteins were identified, which were mainly related to secondary metabolites. The lysine-rich storage globulins and endogenous phytohormones probably contributed the increased lysine content in quinoa during germination. Furthermore, aspartic acid semialdehyde dehydrogenase is essential for lysine synthesis in addition to aspartate kinase and dihydropyridine dicarboxylic acid synthase. Protein-protein interaction analysis indicated lysine biosynthesis is associated with "amino metabolism" and "starch and sucrose metabolism". Above all, our study screens the candidate genes participated in lysine accumulation and explores the factors affected lysine biosynthesis by multi-omics analysis. These information not only paves a foundation for breeding lysine-rich quinoa sprouts but also provides valuable multi-omics resource to explore the characteristic of nutrients during quinoa germination.

Anthocyanins are water-soluble plant pigments mainly stored in the plant vacuoles. Glutathione S-transferases (GSTs) are a multifunctional enzyme family, which can regulate substance metabolism and biological and abiotic stresses in plants. However, few reports were focused on the involvement of GSTs in anthocyanin sequestration in red skin radish. Here, we identified a glutathione S-transferase gene RsGSTF12 that played roles in anthocyanin sequestration in radish. The bioinformatics analysis revealed that RsGSTF12 belonged to the phi (F) class of glutathione S-transferases and showed a high homology with AtGSTF12, followed by AtGSTF11. The subcellular localization assay showed that RsGSTF12 was located in the endoplasmic reticulum and tonoplast. Temporal and spatial gene expression-specific analyses uncovered a strong correlation of RsGSTF12 with anthocyanin accumulation in radish sprouts. The anthocyanin solubility assay found RsGSTF12 was capable of improving cyanidin water solubility in vitro. Transiently expressing RsGSTF12 in radish cotyledons was able to increase their anthocyanin sequestrations. Furthermore, the functional complementation and overexpression of the Arabidopsis thaliana tt19 mutant and wild type demonstrated that RsGSTF12 might play an indispensable role in anthocyanin accumulation in radish. Taken together, we provide compelling evidence that RsGSTF12 functions critically in how anthocyanins are sequestrated in radish, which may enrich our understanding of the mechanism of anthocyanin sequestration.

Indole-3-carbinol (I3C), an important secondary metabolite with strong anti-cancer ability, is widely found in cruciferous plants. Light and phytohormones are one of the most important external and internal signals, respectively, that control the growth, development, and secondary metabolism of the plant life cycle. However, there are few studies about the influence of the blue light and salicylic acid (SA) on the regulation of I3C accumulation. In this study, a negative correlation was found between the content of I3C and SA in different species. Among this, broccoli and Arabidopsis thaliana were chosen for further studies. We observed that blue light treatment increased the accumulation of I3C, and exogenous SA treatment significantly inhibited the accumulation of I3C in broccoli sprouts. Based on the RNA sequence, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that blue light promoted the enrichment of differentially expressed genes (DEGs) in plant hormone signal transduction pathways. More specifically, downregulated expression of genes related to SA biosynthesis and upregulated expression of I3C genes related to metabolic pathway were observed under blue light. Taken together, these results suggested that SA negatively regulates blue light-induced I3C accumulation in broccoli sprouts.

BACKGROUND:The health benefits of anthocyanins impel researchers and food producers to explorer new methods to increase anthocyanin contents in plant foods. Our previous studies revealed a positive role of nitric oxide (NO) in anthocyanin accumulation in radish (Raphanus sativus L.) sprouts. The application of hemin, an inducer of heme oxygenase-1 (HO-1), can effectively elevate NO production in vivo. Hemin treatment also improves plant growth and stress tolerance. This study is aimed to assess the effects of hemin treatment on anthocyanin production in radish sprouts, and to investigate whether NO signalling is involved in this process.RESULTS:The application of hemin significantly up regulated the expressions of many anthocyanins biosynthesis related structure and regulatory genes, leading to increased anthocyanins accumulation in radish hypocotyls. Hemin treatment also raised NO contents in radish sprouts, probably through enhancing nitrate reductase (NR) activity and Nitric Oxide-Associated 1 (NOA1) expression. Comparing the effects of Zinc Protoporphyrin (ZnPP, HO-1 activity inhibitor), Sodium Nitroprusside (SNP, NO donor) and carboxy-PTIO (cPTIO, NO-scavenger) on anthocyanin and NO production, a positive role of NO signalling has been revealed in hemin-derived anthocyanin accumulation. A positive feedback loop between HO-1 and NO may be involved in regulating this process.CONCLUSIONS:Hemin induced anthocyanin accumulation in radish sprouts through HO-1 and NO signalling network.

豆类作物是我国重要的经济作物,在种植业中有较高的地位.杂种优势的利用可提高产量.雄性不育是花粉或花药发育异常的现象.雄性不育系的利用为杂种优势的利用提供了重要材料和思路.生物技术手段的发展和模式植物拟南芥的花粉和花药发育分子遗传传机制的深入研究,为近几年对大豆细胞质雄性不育、细胞核雄性不育及育性恢复基因的分子遗传机制研究提供技术和理论的依据,并使相关研究取得了一定进展.在此基础上,其他豆类雄性不育的分子遗传机制及杂种优势利用的研究也有所突破.本文综述了植物花粉发育的分子遗传机理以及豆类作物雄性不育分子遗传机制和杂种优势利用的研究进展,为豆类作物杂种优势的相关研究提供较为全面的信息.

Gypsum (calcium sulfate dihydrate, CaSO4 ·2H₂O) is commonly applied to improve soil quality and nutrient supply. Previous studies also suggested it is a cost-effective soil amendment in alleviating cadmium (Cd) toxicity and accumulation in plants. The aim of this study was to investigate how this is achieved. We used pak choi as our research material because it is a popular vegetable in Asia, and as a leafy vegetable, it accumulates higher Cd level than other types of vegetable. Under Cd stress, application of CaSO4 promoted pak choi seedling growth, decreased the oxidative stress in roots, reduced Cd accumulation, and enhanced the photosynthesis in shoots. We revealed the inhibition of Cd2+ absorption by CaSO4 is largely due to the competition between Ca2+ and Cd2+ for ion channels or transporter. Moreover, under Cd stress, CaSO4 facilitated the sulphate assimilation, increased the biosynthesis of phytochelatins, and activated the expression of transporters for vacuolar sequestration. Together, CaSO4 could benefit plant growth and enhance Cd tolerance by suppressing Cd root uptake and lowering the Cd content in cytoplasm.

Cadmium (Cd) is one of the toxic heavy metals in soil, which not only suppresses crop production but also threatens human health. In this study, we aim to clarify the biological function of Cd-related gene BcHIPP16, so as to provide potential genetic solutions to decrease the Cd levels of pak choi. Tissue expression analysis showed that BcHIPP16 expressed in almost all the plant bodies. The transcriptional level of BcHIPP16 in roots was higher than that in shoots, which was significantly induced by copper (Cu) deficiency and Cd exposure conditions. Subcellular localization revealed that BcHIPP16 localized in plasma membrane. Expressing BcHIPP16 in yeast cells improved the sensitivity to Cu and Cd and improved their accumulation in yeast. Furthermore, the Cu and Cd content of Arabidopsis seedlings were increased and complemented, respectively when expressing BcHIPP16 in wild type (WT) and hip16 mutants. Non-invasive Micro-test Technology (NMT) was used to measure the realtime Cd2+ influx from the root surface of BcHIPP16 transgenic Arabidopsis lines, and the result demonstrated that BcHIPP16 promoted Cd2+ influx into Arabidopsis root cells. Taken together, our study showed that BcHIPP16 contributed to absorbing nutrient metal Cu and heavy metal Cd in planta.

Quinoa (Chenopodium quinoa Willd.) with a history of 5000 years as food is extremely rich in nutrients and bioactive compounds, including γ-aminobutyric acid (GABA), a natural four-carbon non-protein amino acid with great benefits to human health. In quinoa, GABA generally increases with the germination time, but the underlying molecular mechanism is unclear. Here, we found that the GABA content in quinoa varied significantly among 25 varieties using an automatic amino acid analyzer. Next, six varieties (three low-GABA and three high-GABA varieties) were used for further analyses. The content of GABA in six varieties all showed an increasing trend after germination. In addition, Pearson's correlation analysis showed that the changes in GABA content were closely related to the transcript level or enzyme activity of three key enzymes including glutamate decarboxylase (GAD), GABA transaminase (GABA-T), and succinate-semialdehyde dehydrogenase (SSADH) in the GABA shunt, especially GAD. Based on RNA-sequencing analysis, eight GAD genes, two GABA-T genes, one SSADH gene, nine polyamine oxidase (PAO) genes, five diamine oxidase (DAO) genes, four 4-aminobutyraldehyde dehydrogenase (BADH) genes, and three thermospermine synthase ACAULIS5 (ACL5) genes were identified. Among these, CqGAD8 and CqGABA-T2 may make a greater contribution to GABA accumulation during quinoa germination.

Cadmium (Cd) is a toxic nonessential metal that poses a health risk for humans. Cd is easily accumulated in leaf vegetables than in other vegetables. Leafy vegetables are one of the major dietary Cd sources for the human body. In this study, pak choi was used as our experimental material as it is an important leafy vegetable, especially in Asia. A NRAMP transporter - BcNRAMP1 was identified in pak choi, which is involved in manganese (Mn) and Cd uptake in yeast and in planta. BcNRAMP1 is expressed in the whole plant body of pak choi, with a higher abundance in root tissues than in shoots. Mn deficiency and Cd exposure strongly induced BcNRAMP1 transcription levels. Through transient expression of BcNRAMP1-GFP fusion protein in tobacco leaf epidermal cells, BcNRAMP1 was revealed as a plasma membrane protein. Expressing BcNRAMP1 in yeast enhanced yeast cells to absorb Mn, Cd, and iron (Fe). Overexpression of BcNRAMP1 in Arabidopsis wild-type and nramp1 mutant increased and complemented Mn and Cd transportation and accumulation, respectively. Using noninvasive microelectrode ion flux measurements, a direct evidence that BcNRAMP1 acts on Cd influx in Arabidopsis root cells was provided. The results of this study reveal that BcNRAMP1 functions as a NRAMP protein in planta, absorbing nutrient metal Mn and the toxic metal Cd.

When plants are exposed to hypoxic conditions, the level of g-aminobutyric acid (GABA) in plant tissues increases by several orders of magnitude. The physiological rationale behind this elevation remains largely unanswered. By combining genetic and electrophysiological approach, in this work we show that hypoxia-induced increase in GABA content is essential for restoration of membrane potential and preventing ROS-induced disturbance to cytosolic K+ homeostasis and Ca2+ signaling. We show that reduced O-2 availability affects H+-ATPase pumping activity, leading to membrane depolarization and K+ loss via outward-rectifying GORK channels. Hypoxia stress also results in H2O2 accumulation in the cell that activates ROS-inducible Ca2+ uptake channels and triggers self-amplifying "ROS-Ca hub,'' further exacerbating K+ loss via non-selective cation channels that results in the loss of the cell's viability. Hypoxia-induced elevation in the GABA level may restore membrane potential by pH-dependent regulation of H+-ATPase and/or by generating more energy through the activation of the GABA shunt pathway and TCA cycle. Elevated GABA can also provide better control of the ROS-Ca2+ hub by transcriptional control of RBOH genes thus preventing over-excessive H2O2 accumulation. Finally, GABA can operate as a ligand directly controlling the open probability and conductance of K+ efflux GORK channels, thus enabling plants adaptation to hypoxic conditions.

随着土壤和大气沉降物中重金属污染的问题日益严峻,农作物重金属超标时有发生.土壤中的重金属难以降解,容易被植物根部吸收,在作物中积累;大气中的重金属沉降到叶片上,通过叶片吸收进入作物中,最终通过食物链被人类食用,危害人体健康.水稻是我国最重要的粮食作物,大米中存在镉超标问题.镉(Cd)是水稻的非必需元素,主要借助其他金属离子通道蛋白进入水稻根细胞,还可以通过叶片角质层的吸附内化和气孔的渗透作用进入水稻叶片.Cd依赖其他金属离子的转运体在水稻体内运输,Cd从土壤中吸收和植物内部的分配是一个动态过程,通过根吸收转运蛋白、根-地上部转运(木质部转运)和韧皮部的源-库转运(包括种子装载)驱动,实现器官间的转运分配.本文综述了水稻Cd的吸收与转运、器官间Cd的运输分配以及Cd向籽粒转运积累,以期为减少水稻籽粒中Cd含量的研究和解决我国南方部分种植地区Cd污染问题提供一些参考.

The accumulation of calcium nitrate [Ca(NO3)2] in the edible part of vegetables is one of the main reasons for the reduction of production and is harmful to human health, but so far, there is no effective method to solve environmentally problem. In this study, an environmentally friendly hydrogen-rich water (HRW) was used to study its effect on alleviating the growth inhibition of Brassica campestris spp. chinensis L. seedlings exposed to excessive Ca(NO3)2. The results of Chinese cabbage seedlings exposed to excessive Ca(NO3)2 showed that the nitrate content in edible parts of seedlings was reduced by exogenous HRW by promoting seedling growth, reducing oxidative stress, and reducing the excess of 80 mM Ca(NO3)2 which was toxic effects in the edible part of the seedlings. The conclusion was supported by the following results: (1) when Ca(NO3)2 was added excessively, HRW could effectively reduce the growth inhibition of Chinese cabbage seedlings by increasing root lengths and leaves and roots weights; (2) HRW inhibited the accumulation of the O2·−, H2O2, MDA and the conductivity of relative electrical under Ca(NO3)2 through increasing the activity of antioxidant enzymes (SOD, POD, CAT, APX); (3) HRW was processed by transporters (BcNRT1.5 and BcNRT1.8), which allowed more nitrates to be stored in the roots and reduces transport to the ground.

Soybean sprouts are a flavorful microgreen that can be eaten all year round and are widely favored in Southeast Asia. In this study, the regulatory mechanism of calcium on anthocyanin biosynthesis in soybean sprouts under blue light was investigated. The results showed that blue light, with a short wavelength, effectively induced anthocyanin accumulation in the hypocotyl of soybean sprout cultivar “Dongnong 690.” Calcium supplementation further enhanced anthocyanin content, which was obviously inhibited by LaCl3 and neomycin treatment. Moreover, exogenous calcium changed the metabolism of anthocyanins, and seven anthocyanin compounds were detected. The trend of calcium fluorescence intensity in hypocotyl cells, as well as that of the inositol 1,4,5-trisphosphate and calmodulin content, was consistent with that of anthocyanins content. Specific spatial distribution patterns of calcium antimonate precipitation were observed in the ultrastructure of hypocotyl cells under different conditions. Furthermore, calcium application upregulated the expression of genes related to anthocyanin biosynthesis, and calcium inhibitors suppressed these genes. Finally, transcriptomics was performed to gain global insights into the molecular regulation mechanism of calcium-associated anthocyanin production. Genes from the flavonoid biosynthesis pathway were distinctly enriched among the differentially expressed genes, and weighted gene co-expression network analysis showed that two MYBs were related to the accumulation of anthocyanins. These results indicated that calcium released from apoplast and intracellular stores in specific spatial-temporal features promote blue light-induced anthocyanin accumulation by upregulation of the expression of genes related to anthocyanin synthesis of “Dongnong 690” hypocotyl. The findings deepen the understanding of the calcium regulation mechanism of blue light-induced anthocyanin accumulation in soybean sprouts, which will help growers produce high-quality foods beneficial for human health.

CRISPR基因编辑技术逐渐成为一个强有力的分子技术,已越来越广泛地应用于科学研究和临床试验.在高校教学实践中,为了解决该实验原理复杂、操作难度大、周期长、成本高等问题,构建了CRISPR基因编辑仿真教学软件.该软件包括原理演示和实训操作2个模块.原理部分通过3D技术呈现出每个分子的结构,并以动画的形式演绎CRISPR-Cas9的分子机制.实训操作部分模拟了整个实验的操作过程,学生可以通过互动的形式在电脑上反复学习和操作.该交互式虚拟实验能激发学生的学习兴趣,显著提高实验教学质量.