Species- and organ-specific contribution of peroxisomal cinnamate:CoA ligases to benzoic and salicylic acid biosynthesis.

Salicylic acid (SA) is a prominent defense hormone whose basal level, organ-specific accumulation, and physiological role vary widely among plant species. Of the two known pathways of plant SA biosynthesis, the phenylalanine ammonia lyase (PAL) pathway is more ancient and universal but its biosynthetic and physiological roles in diverse plant species remain unclear. Studies in which the PAL pathway is specifically or completely inhibited, as well as a direct comparison of diverse species and different organs within the same species, are needed.

Sequencing and Analysis of Complete Chloroplast Genomes Provide Insight into the Evolution and Phylogeny of Chinese Kale ( var. ).

Chinese kale is a widely cultivated plant in the genus in the family Brassicaceae. The origin of has been studied extensively, but the origin of Chinese kale remains unclear. In contrast to , which originated in the Mediterranean region, Chinese kale originated in southern China.

CRISPR/Cas9-mediated BoaAOP2s editing alters aliphatic glucosinolate side-chain metabolic flux and increases the glucoraphanin content in Chinese kale.

Glucoraphanin (GRA) is an aliphatic glucosinolate (GSL), and its hydrolysis product has powerful anticancer activity. ALKENYL HYDROXALKYL PRODUCING 2 (AOP2) gene, encodes a 2-oxoglutarate-dependent dioxygenase, which can catalyze GRA to form gluconapin (GNA). However, GRA only present in trace amounts in Chinese kale.

Enhancing health-promoting isothiocyanates in Chinese kale sprouts via manipulating .

Glucosinolates (GSLs) are a group of sulfur-containing secondary metabolites, which are abundant in vegetables. GSL breakdown products (GBPs), especially isothiocyanates (ITCs) benefit human health. Chinese kale is a native vegetable in China, and its sprouts are rich in GSLs and nutritional substances.

Brassinosteroids fine-tune secondary and primary sulfur metabolism through BZR1-mediated transcriptional regulation.

For adaptation to ever-changing environments, plants have evolved elaborate metabolic systems coupled to a regulatory network for optimal growth and defense. Regulation of plant secondary metabolic pathways such as glucosinolates (GSLs) by defense phytohormones in response to different stresses and nutrient deficiency has been intensively investigated, while how growth-promoting hormone balances plant secondary and primary metabolism has been largely unexplored. Here, we found that growth-promoting hormone brassinosteroid (BR) inhibits GSLs accumulation while enhancing biosynthesis of primary sulfur metabolites, including cysteine (Cys) and glutathione (GSH) both in Arabidopsis and Brassica crops, fine-tuning secondary and primary sulfur metabolism to promote plant growth.

WRKY33-mediated indolic glucosinolate metabolic pathway confers resistance against Alternaria brassicicola in Arabidopsis and Brassica crops.

The tryptophan (Trp)-derived plant secondary metabolites, including camalexin, 4-hydroxy-indole-3-carbonylnitrile, and indolic glucosinolate (IGS), show broad-spectrum antifungal activity. However, the distinct regulations of these metabolic pathways among different plant species in response to fungus infection are rarely studied. In this study, our results revealed that WRKY33 directly regulates IGS biosynthesis, notably the production of 4-methoxyindole-3-ylmethyl glucosinolate (4MI3G), conferring resistance to Alternaria brassicicola, an important pathogen which causes black spot in Brassica crops.

Characterization of the Role of the Neoxanthin Synthase Gene in Carotenoid Biosynthesis in Chinese Kale.

Chinese kale ( var. ) is rich in carotenoids, and neoxanthin is one of the most important carotenoids in Chinese kale. In this study, the function of the neoxanthin synthase gene () in Chinese kale was investigated.

Improvement of glucosinolates by metabolic engineering in crops.

Glucosinolates (GSLs) are a class of sulfur- and nitrogen-containing, and amino acid-derived important secondary metabolites, which mainly present in plants of Brassicaceae family, including crops, such as broccoli, cabbage, and oilseed rape. The bioactive GSL metabolites confer benefits to plant defense, human health, and the unique flavor of some crops. However, certain GSL profiles have adverse effects and are known as anti-nutritional factors.

Characterization of Reveals Its Role in Carotenoid Biosynthesis in Chinese Kale.

Carotenoids are organic pigments that play an important role in both plant coloration and human health; they are a critical subject in molecular breeding due to growing demand for natural molecules in both food and medicine. In this study, we focus upon characterizing , the carotenoid isomerase gene before the branch of the carotenoid biosynthetic pathway, which is expressed in all organs and developmental stages of Chinese kale, and BoaCRTISO, which is located in the chloroplast. The expression of is induced by strong light, red and blue combined light, and gibberellic acid treatment, but it is suppressed by darkness and abscisic acid treatment.

The flavor of Chinese kale sprouts is affected by genotypic variation of glucosinolates and their breakdown products.

Metabolic profiling of glucosinolates and their breakdown products in sprouts of 22 Chinese kale (Brassica oleracea var. alboglabra, BOA) varieties were investigated by using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). Relationships between glucosinolate metabolites and flavor of Chinese kale sprouts were also analyzed.

Virus-induced phytohormone dynamics and their effects on plant-insect interactions.

Attacks on plants by both viruses and their vectors is common in nature. Yet the dynamics of the plant-virus-vector tripartite system, in particular the effects of viral infection on plant-insect interactions, have only begun to emerge in the last decade. Viruses can modulate the interactions between insect vectors and plants via the jasmonate, salicylic acid and ethylene phytohormone pathways, resulting in changes in fitness and viral transmission capacity of their insect vectors.

Effect of melatonin treatment on visual quality and health-promoting properties of broccoli florets under room temperature.

Effect of melatonin treatment on visual quality and contents of health-promoting compounds of broccoli florets under room temperature was investigated in the present study. Broccoli florets were treated with 1 μM melatonin and then stored at room temperature. Results showed that melatonin treatment could delay the post-harvest senescence of broccoli, and performed well in maintaining higher levels of antioxidants, such as carotenoids, vitamin C and total phenols, as well as higher antioxidant capacity than the control.

Combined treatment of epi-brassinolide and NaCl enhances the main phytochemicals in Chinese kale sprouts.

The effects of individual epi-brassinolide (eBL) and NaCl, as well as their combination on contents of main phytochemicals and antioxidant capacity of Chinese kale sprouts were investigated. Our results showed that the application of 100 nM eBL decreased the contents of individual and total glucosinolates, while treatments of 160 mM NaCl both alone and combined with 100 nM eBL enhanced the glucosinolates accumulation by promoting the expression of genes involved in glucosinolate biosynthesis in Chinese kale sprouts and the combined treatment led to significantly higher content of most glucosinolate profiles. Moreover, it also elevated the contents of ascorbic acid and total carotenoids, whereas did not influence the total phenolics and antioxidant capacity.

The γ-tubulin complex protein GCP6 is crucial for spindle morphogenesis but not essential for microtubule reorganization in .

γ-Tubulin typically forms a ring-shaped complex with 5 related γ-tubulin complex proteins (GCP2 to GCP6), and this γ-tubulin ring complex (γTuRC) serves as a template for microtubule (MT) nucleation in plants and animals. While the γTuRC takes part in MT nucleation in most eukaryotes, in fungi such events take place robustly with just the γ-tubulin small complex (γTuSC) assembled by γ-tubulin plus GCP2 and GCP3. To explore whether the γTuRC is the sole functional γ-tubulin complex in plants, we generated 2 mutants of the gene encoding the largest subunit of the γTuRC in .

Main Health-Promoting Compounds Response to Long-Term Freezer Storage and Different Thawing Methods in Frozen Broccoli Florets.

The effects of long-term freezer storage and different defrosting methods on the retention of glucosinolates, vitamin C, and total phenols in frozen broccoli florets were investigated in the present study. Frozen broccoli florets were stored in a freezer at -20 °C for 165 days or subjected to defrosting by three different house-hold thawing methods (water, air, and refrigerator defrosting). Results showed that all glucosinolates were well preserved, while vitamin C and total phenols were reduced by less than 12% and 19% of the control, respectively, during the storage.

Functional Characterization of BoaMYB51s as Central Regulators of Indole Glucosinolate Biosynthesis in var. Bailey.

R2R3-MYB transcription factor MYB51 is known to control indole glucosinolate (indole GSL) biosynthesis in . Here, two copies of have been isolated in Chinese kale ( var. Bailey), designated and , which exhibit overlapping but distinct expression levels among different organs and respond to signaling molecules in a similar pattern.

Effects of postharvest methyl jasmonate treatment on main health-promoting components and volatile organic compounds in cherry tomato fruits.

Effects of postharvest methyl jasmonate (MeJA) treatment on the contents of ascorbic acid and carotenoids, as well as the compositions and contents of volatile organic compounds (VOCs) in cherry tomato fruits were investigated during 11 days of storage at room temperature (25 °C). The results showed that MeJA treatment significantly increased the contents of ascorbic acid and carotenoids, especially lycopene in postharvest cherry tomato fruits. Moreover, MeJA treatment improved the contents of carotenoids derived VOCs such as 6-methyl-5-hepten-2-one (MHO), while had no effect on firmness, sugars and titratable acidity.

Effects of glucose and gibberellic acid on glucosinolate content and antioxidant properties of Chinese kale sprouts.

Glucosinolates, anthocyanins, total phenols, and vitamin C, as well as antioxidant capacity, were investigated in Chinese kale sprouts treated with both glucose and gibberellic acid (GA). The combination of 3% (0.03 g/ml) glucose and 5 μmol/L GA treatment was effective in increasing glucosinolate content while glucose or GA treatment alone did not influence significantly almost all individual glucosinolates or total glucosinolates.

Influence of pre-harvest red light irradiation on main phytochemicals and antioxidant activity of Chinese kale sprouts.

The effects of pre-harvest red light irradiation on main healthy phytochemicals as well as antioxidant activity of Chinese kale sprouts during postharvest storage were investigated. 6-day-old sprouts were treated by red light for 24h before harvest and sampled for further analysis of nutritional quality on the first, second and third day after harvest. The results indicated that red light exposure notably postponed the degradation of aliphatic, indole, and total glucosinolates during postharvest storage.

Glucose enhances indolic glucosinolate biosynthesis without reducing primary sulfur assimilation.

The effect of glucose as a signaling molecule on induction of aliphatic glucosinolate biosynthesis was reported in our former study. Here, we further investigated the regulatory mechanism of indolic glucosinolate biosynthesis by glucose in Arabidopsis. Glucose exerted a positive influence on indolic glucosinolate biosynthesis, which was demonstrated by induced accumulation of indolic glucosinolates and enhanced expression of related genes upon glucose treatment.

Effects of industrial pre-freezing processing and freezing handling on glucosinolates and antioxidant attributes in broccoli florets.

The effects of industrial pre-freezing processing and freezing handling on the contents of glucosinolates and antioxidants (vitamin C, polyphenols, carotenoid and chlorophyll), as well as the antioxidant capacity in broccoli (Brassica oleracea L. var. italica) florets were investigated in the present study.

Effects of light quality on main health-promoting compounds and antioxidant capacity of Chinese kale sprouts.

The effects of different light qualities, including white, red and blue lights, on main health-promoting compounds and antioxidant capacity of Chinese kale sprouts were investigated using light-emitting diodes (LEDs) as a light source. Our results showed that blue light treatment significantly decreased the content of gluconapin, the primary compound for bitter flavor in shoots, while increased the glucoraphanin content in roots. Moreover, the maximum content of vitamin C was detected in the white-light grown sprouts and the highest levels of total phenolic and anthocyanins, as well as the strongest antioxidant capacity were observed in blue-light grown sprouts.

Classic myrosinase-dependent degradation of indole glucosinolate attenuates fumonisin B1-induced programmed cell death in Arabidopsis.

The mycotoxin fumonisin B1 (FB1) causes the accumulation of reactive oxygen species (ROS) which then leads to programmed cell death (PCD) in Arabidopsis. In the process of studying FB1-induced biosynthesis of glucosinolates, we found that indole glucosinolate (IGS) is involved in attenuating FB1-induced PCD. Treatment with FB1 elevates the expression of genes related to the biosynthesis of camalexin and IGS.