The crotonylated and succinylated proteins of jujube involved in phytoplasma-stress responses.

BACKGROUND: Protein posttranslational modifications (PTMs) are fast and early responses to environmental changes, including pathogen infection. Jujube witches' broom (JWB) is a phytoplasma disease causing great economic loss in jujube production. After phytoplasma infection, the transcriptional, translational, and metabolic levels in jujube were activated, enabling it to survive during phytoplasma invasion. However, no study has yet reported on PTMs in jujube. Lysine crotonylation (Kcr) and lysine succinylation (Ksu) have been popular studies in recent years and their function in plant phytoplasma-stress responses remains unclear. RESULTS: Here, 1656 crotonylated and 282 succinylated jujube proteins were first identified under phytoplasma-stress, of which 198 were simultaneously crotonylated and succinylated. Comparative analysis revealed that 656 proteins, 137 crotonylated and 43 succinylated proteins in jujube were regulated by phytoplasma infection, suggesting that Kcr was more universal than Ksu. Kcr differentially expressed proteins (DEPs) were related to ribosomes, photosynthetic and carbon metabolism, while Ksu DEPs were mainly involved in carbon metabolism, the TCA cycle and secondary metabolite biosynthesis. The crosstalk network among proteome, crotonylome and succinylome showed that DEPs related to ribosomal, peroxidases and glutathione redox were enriched. Among them, ZjPOD51 and ZjPHGPX2 significantly increased at the protein and Kcr level under phytoplasma-stress. Notably, 7 Kcr sites were identified in ZjPHGPX2, a unique antioxidant enzyme. After inhibitor nicotinamide (NAM) treatment, GPX enzyme activity in jujube seedlings was reduced. Further, site-directed mutagenesis of key Kcr modification sites K130 and/or K135 in ZjPHGPX2 significantly reduced its activity. CONCLUSIONS: This study firstly provided large-scale datasets of Kcr and Ksu in phytoplasma-infected jujube and revealed that Kcr modification in ZjPHGPX2 positively regulates its activity.

Screening of Oral Potential Angiotensin-Converting Enzyme Inhibitory Peptides from Zizyphus jujuba Proteins Based on Gastrointestinal Digestion In Vivo.

Plant proteins are a good source of active peptides, which can exert physiological effects on the body. Predicting the possible activity of plant proteins and obtaining active peptides with oral potential are challenging. In this study, the potential activity of peptides from Zizyphus jujuba proteins after in silico simulated gastrointestinal digestion was predicted using the BIOPEP-UWM™ database. The ACE-inhibitory activity needs to be further investigated. The actual peptides in mouse intestines after the oral administration of Zizyphus jujuba protein were collected and analyzed, 113 Zizyphus jujuba peptides were identified, and 3D-QSAR models of the ACE-inhibitory activity were created and validated using a training set (34 peptides) and a test set (12 peptides). Three peptides, RLPHV, TVKPGL and KALVAP, were screened using the 3D-QSAR model and were found to bind to the active sites of the ACE enzyme, and their IC50 values were determined. Their values were 6.01, 3.81, and 17.06 µM, respectively. The in vitro digestion stabilities of the RLPHV, TVKPGL, and KALVAP peptides were 82%, 90%, and 78%. This article provides an integrated method for studying bioactive peptides derived from plant proteins.

Genome-wide analysis of ALDH gene family in jujube and identification of ZjALDH3F3 for its important role in high-temperature tolerance.

Aldehyde dehydrogenases (ALDHs) are NAD(P)-dependent enzymes that oxidize aliphatic and aromatic aldehydes. They play crucial roles in various biological processes and plant responses to stress. The impact of high temperatures on jujube quality and yield has been well documented. Nevertheless, the involvement of ALDHs in the response to heat stress remains poorly understood. This study aimed to identify ZjALDHs in the jujube genome (Ziziphus jujuba var. spinosa) and conducted in silico analyses. Phylogenetic analyses indicated that ALDHs in plants, including jujube, can be divided into ten families, and members from the same family share conserved gene and protein structures. Quantitative real-time PCR (qRT-PCR) and ß-glucuronidase (GUS) histochemical staining were used to analyze the expression patterns of ZjALDHs in response to elevated temperatures. We identified a ZjALDH (ZjALDH3F3) gene displaying a significant upregulation and down-regulation, respectively in heat-resistant (HR) and heat-sensitive (HS) jujube in response to heat treatments. Such specific responses are probably attributed to the different heat-responsive cis-elements of ZjALDH3F3 in HR and HS jujubes. ZjALDH3F3 over-expressed in tobacco increased heat tolerance, as evidenced by the reduced accumulation of reactive oxygen species (ROS) and elevated activity of antioxidant enzymes. The qRT-PCR results indicated that the expression of antioxidant enzymes, abscisic acid (ABA), and stress-responsive genes was enhanced in transgenic tobacco. This study sheds novel light on the function of ZjALDHs in heat resistance of jujube.

The resistance of the jujube (Ziziphus jujuba) to the devastating insect pest Apolygus lucorum (Hemiptera, Insecta) involves the jasmonic acid signaling pathway.

Apolygus lucorum (Hemiptera, Insecta), cosmopolitan true bug, is a major pest of the Chinese jujube (Ziziphus jujuba). To propose control measures of A. lucorum, we investigated the molecular mechanisms of resistance in two varieties of jujube (wild jujube and winter jujube) with different sensitivities to this pest. We monitored changes of two species of jujube in the transcriptome, jasmonic acid (JA) and salicylic acid (SA) content, and the expression of genes involved in signaling pathways. The preference of A. lucorum for jujube with exogenous SA and methyl jasmonate (MeJA) were also examined. The results showed that wild jujube leaves infested by A. lucorum showed stronger resistance and non-selectivity to A. lucorum than winter jujube. By comparing data from the A. lucorum infested plants with the control, A total of 438 and 796 differentially expressed genes (DEGs) were found in winter and wild jujube leaves, respectively. GO analysis revealed that biological process termed "plant-pathogen interactions", "plant hormone transduction" and "phenylpropanoid biosynthesis". Most of DEGs enriched in JA pathways were upregulated, while most DEGs of SA pathways were downregulated. A. lucorum increased the JA content but decreased the SA content in jujube. Consistently, the JA and SA contents in winter jujube were lower than those in wild jujube leaves. The key genes ZjFAD3, ZjLOX, ZjAOS, ZjAOC3 and ZjAOC4 involved in JA synthesis of jujube leaves were significantly up-regulated after A. lucorum infestation, especially the expression and up-regulation ratio of ZjFAD3, ZjLOX and ZjAOS in wild jujube were significantly higher than those in winter jujube. MeJA-treated jujube showed an obvious repellent effect on A. lucorum. Based on these findings, we conclude that A. lucorum infestation of jujube induced the JA pathway and suppressed the SA pathway. In jujube leaves the ZjFAD3, ZjLOX and ZjAOS played important roles in increasing of JA content in jujube leaves. Thus, JA played an important role in repelling and resisting against A. lucorum in jujube.

Influences of Jujube Witches' Broom (JWB) Phytoplasma Infection and Oxytetracycline Hydrochloride Treatment on the Gene Expression Profiling in Jujube.

Jujube witches' broom disease (JWB), caused by Candidatus Phytoplasma ziziphi, is the most destructive phytoplasma disease threatening the jujube industry. Tetracycline derivatives treatments have been validated to be capable of recovering jujube trees from phytoplasma infection. In this study, we reported that oxytetracycline hydrochloride (OTC-HCl) trunk injection treatment could recover more than 86% of mild JWB-diseased trees. In order to explore the underlying molecular mechanism, comparative transcriptomic analysis of healthy control (C group), JWB-diseased (D group) and OTC-HCl treated JWB-diseased (T group) jujube leaves was performed. In total, 755 differentially expressed genes (DEGs), including 488 in 'C vs. D', 345 in 'D vs. T' and 94 in 'C vs. T', were identified. Gene enrichment analysis revealed that these DEGs were mainly involved in DNA and RNA metabolisms, signaling, photosynthesis, plant hormone metabolism and transduction, primary and secondary metabolisms, their transportations, etc. Notably, most of the DEGs identified in 'C vs. D' displayed adverse change patterns in 'D vs. T', suggesting that the expression of these genes was restored after OTC-HCl treatment. Our study revealed the influences of JWB phytoplasma infection and OTC-HCl treatment on gene expression profiling in jujube and would be helpful for understanding the chemotherapy effects of OTC-HCl on JWB-diseased jujube.

The genome of Candidatus phytoplasma ziziphi provides insights into their biological characteristics.

Phytoplasmas are obligate cell wall-less prokaryotic bacteria that primarily multiply in plant phloem tissue. Jujube witches' broom (JWB) associated with phytoplasma is a destructive disease of jujube (Ziziphus jujuba Mill.). Here we report the complete 'Candidatus Phytoplasma ziziphi' chromosome of strain Hebei-2018, which is a circular genome of 764,108-base pairs with 735 predicted CDS. Notably, extra 19,825 bp (from 621,995 to 641,819 bp) compared to the previously reported one complements the genes involved in glycolysis, such as pdhA, pdhB, pdhC, pdhD, ackA, pduL and LDH. The synonymous codon usage bias (CUB) patterns by using comparative genomics analysis among the 9 phytoplasmas were similar for most codons. The ENc-GC3s analysis among the 9 phytoplasmas showed a greater effect under the selection on the CUBs of phytoplasmas genes than mutation and other factors. The genome exhibited a strongly reduced ability in metabolic synthesis, while the genes encoding transporter systems were well developed. The genes involved in sec-dependent protein translocation system were also identified.The expressions of nine FtsHs encoding membrane associated ATP-dependent Zn proteases and Mn-SodA with redox capacity in the Ca. P. ziziphi was positively correlated with the phytoplasma concentration. Taken together, the genome will not only expand the number of phytoplasma species and provide some new information about Ca. P. ziziphi, but also contribute to exploring its pathogenic mechanism.

Comparative transcriptome profiling analysis provides insight into the mechanisms for sugar change in Chinese jujube (Ziziphus jujuba Mill.) under rain-proof cultivation.

Chinese jujube (Ziziphus jujuba Mill.) is a globally popular and economically important fruit that is rich in bioactive compounds with strong anti-cancer effects. Rain-proof cultivation is widely used to cultivate Chinese jujube, as it helps avoid rainfall damage during fruit harvest. Although the sugar content of jujube fruits differs between rain-proof and open-field cultivation, the underlying molecular mechanisms are unknown. Here, we analyzed the levels of sugar content, sugar accumulation pattern, and transcriptome profiles of jujube fruits at five developmental stages grown under rain-proof and open-field cultivation modes. The sugar content of jujube fruits was significantly higher under rain-proof cultivation than under open-field cultivation, although the sugar composition and sugar accumulation patterns were comparable. Comparative analysis of transcriptomic profiles showed that rain-proof cultivation enhanced the intrinsic metabolic activity of fruit development. Gene expression and correlation analyses suggested that ZjSPS, ZjSS, ZjHXK, and ZjINV regulate the development-related changes in sugar content in jujube fruits grown under rain-proof cultivation. Temperature, humidity, and moisture conditions were key climatic factors affecting sugar accumulation. Our results provide insights into the molecular mechanisms regulating sugar content and sugar accumulation in Chinese jujube fruits grown under rain-proof cultivation, and we provide genetic resources for studying the development mechanism of Chinese jujube fruit.

Transcriptome Characterization of Pigment-Related Genes in Jujube (Ziziphus Jujuba Mill.) Peel at Different Growth Stages.

One of the most important qualities of jujube fruit is its color. Chlorophyll, carotenoid, and anthocyanin all play important roles in the coloring of jujube fruit. However, few studies have focused on the pigment molecular mechanism. In the present study, jujube peels of 'Sanbianhong' in three growth stages were evaluated for their gene expression characteristics and gene regulation related to pigment formation using the transcriptome sequencing analysis. A total of 84.86 Gb of clean data were obtained in the analysis. In the FS1 vs. FS3, FS1 vs. FS5, and FS3 vs. FS5, 4,530, 11,012, and 9,072 differentially expressed genes (DEGs) were identified, respectively. The inter-group screening among the three comparisons yielded 1430 common DEGs. Among these DEGs, 27, 16, and 28 genes were enriched in chlorophyll, carotenoid, and anthocyanin metabolic pathways, respectively. Twelve genes were chosen at random, and the accuracy of the transcriptome data were confirmed using qRT-PCR. The molecular mechanism underlying the pigmentation of jujube fruit was elucidated at the transcriptome level, which would provide a scientific basis for the subsequent functional studies on the color-regulating genes of jujube fruits.

Methyl Jasmonate- and Salicylic Acid-Induced Transcription Factor ZjWRKY18 Regulates Triterpenoid Accumulation and Salt Stress Tolerance in Jujube.

Triterpenoids are important, pharmacologically active substances in jujube (Ziziphus jujuba Mill.), and play an important role in the plant's resistance to abiotic stress. However, regulation of their biosynthesis, and the underlying mechanism of their balance with stress resistance, remain poorly understood. In this study, we screened and functionally characterized the ZjWRKY18 transcription factor, which is associated with triterpenoid accumulation. The transcription factor is induced by methyl jasmonate and salicylic acid, and its activity was observed by gene overexpression and silencing experiments, combined with analyses of transcripts and metabolites. ZjWRKY18 gene silencing decreased the transcription of triterpenoid synthesis pathway genes and the corresponding triterpenoid content. Overexpression of the gene promoted the biosynthesis of jujube triterpenoids, as well as triterpenoids in tobacco and Arabidopsis thaliana. In addition, ZjWRKY18 binds to W-box sequences to activate promoters of 3-hydroxy-3-methyl glutaryl coenzyme A reductase and farnesyl pyrophosphate synthase, suggesting that ZjWRKY18 positively regulates the triterpenoid synthesis pathway. Overexpression of ZjWRKY18 also increased tolerance to salt stress in tobacco and Arabidopsis thaliana. These results highlight the potential use of ZjWRKY18 to improve triterpenoid biosynthesis and salt stress tolerance in plants, and provide a strong basis for metabolic engineering to improve the content of triterpenoids and breeding of jujube varieties that are resistant to stress.

Glycine betaine inhibits postharvest softening and quality decline of winter jujube fruit by regulating energy and antioxidant metabolism.

Winter jujube fruit easily softens after harvest. To investigate the effects of glycine betaine (N,N,N-trimethylglycine; GB) treatment on the quality of postharvest jujubes, fresh winter jujubes (Zizyphus jujuba Mill. cv. Dongzao) were immersed in 20 mmol·L-1 GB for 20 min. The results showed that GB application can effectively maintain cell wall component content by restraining gene expression and enzyme activities, including PG, CX, PME and ß-Glu. Meanwhile, the activities of antioxidant enzymes (APX, CAT, SOD, POD) and the contents of nonenzymatic antioxidants (MDA, H2O2, ASA, GSH) were enhanced in treated jujubes, thereby reducing the content of ROS. In addition, energy metabolism enzyme activities (H+-ATPase, Ca2+-ATPase, SDH and CCO) and gene expression were also significantly increased, thus maintaining higher energy levels (ATP, ADP, AMP and EC). In summary, GB enhances ATP biosynthesis by increasing energy metabolism. It offers essential energy for the antioxidant metabolism, thus retarding the softening of postharvest jujubes.

Ziziphus spina-christi extract-stabilized novel silver nanoparticle synthesis for combating Fusarium oxysporum-causing pepper wilt disease: in vitro and in vivo studies.

The novelty of the present study is studying the ability of aqueous Ziziphus spina-christi leaves' extract (ZSCE) to produce eco-friendly and cost-effective silver nanoparticles (Ag NPs) against Fusarium wilt disease. Phytochemical screening of ZSCE by HPLC showed that they contain important antimicrobial substances such as Rutin, Naringin, Myricetin, Quercetin, Kaempferol, Hesperidin, Syringeic, Eugenol, Pyrogallol, Gallic and Ferulic. Characterization methods reveal a stable Ag NPs with a crystalline structure, spherical in shape with average particle size about 11.25 nm. ZSCE and Ag NPs showed antifungal potential against F. oxysporum at different concentrations with MIC of Ag NPs as 0.125 mM. Ag NPs treatment was the most effective, as it gave the least disease severity (20.8%) and the highest protection rate (75%). The application of ZSCE or Ag NPs showed a clear recovery, and its effectiveness was not limited for improving growth and metabolic characteristics only, but also inducing substances responsible for defense against pathogens and activating plant immunity (such as increasing phenols and strong expression of peroxidase and polyphenol oxidase as well as isozymes). Owing to beneficial properties such as antifungal activity, and the eco-friendly approach of cost and safety, they can be applied in agricultural field as novel therapeutic nutrients.

Bioactive triterpenes of jujube in the prevention of colorectal cancer and their molecular mechanism research.

BACKGROUND: Jujube, a popular fruit from the Rhamnaceae family, relieves colorectal inflammation caused by spleen deficiency and has been used in many formulas in clinical for decades to treat colorectal cancer (CRC). As of yet, the therapeutic substances and mechanism of their action are unknown. PURPOSE: The purpose of this study is to define the therapeutic substances of jujube and its mechanism of action in treating CRC. METHODS: The pharmacological effects of jujube extract and its fractions were evaluated in vivo using a CRC mouse model induced by AOM/DSS. The DAI value, colon length, mortality, tumor burden, and histological tumor size of the treated animals were compared. To explore the potential therapeutic substances, LC-MS analysis was conducted to characterize the serum migration components. A network pharmacology experiment was carried out for potential molecular targets. To verify the therapeutic substances as well as the molecular mechanism of jujube intervening CRC, cellular MTT assay of the serum migration components, Western blot and IHC tests were conducted. RESULTS: The in vivo pharmacological studies showed that compared to AOM/DSS treated mice, the mortality and DAI value, tumor burden, and histological tumor size of jujube extract and its fat-soluble fraction (mainly contained triterpenes) treated mice were significantly reduced, and their colon lengths were obviously longer than AOM/DSS treated mice. The targeted-LC/MS analysis supposed triterpenes 3, 7, 9, 11, 12, 14, 17 - 21, and 25 - 28 to be the serum migration components, which might be the potential therapeutic substances. In the network pharmacology experiment, the GO annotation and enrichment analysis of the KEGG pathway indicated that PI3K-Akt pathway and inflammatory reaction were important factors for jujube inhibiting CRC. Cellular MTT assay of serum migration components indicated that the potential effective substances from fat-soluble fraction to be triterpenes 3, 7, 17, 19, 20, and 25. The Western blot and IHC assays implied that the jujube extract, its fat-soluble fraction, and triterpenes 7, 17, and 20 showed inhibition on the expression of PI3K/Akt/NF-κB signaling pathway-related proteins. Additionally, it was noted in the pharmacodynamic experiment that ZJL's effectiveness was more apparent than ZJH and SQL in tumor burden rate, colon length, and spleen weight, which indicated that the efficacy of ZJ is contributed from CD and SQ, and they may have a synergistic effect on anti-CRC. CONCLUSION: These results for the first time provide evidence that jujube triterpenes possess an anti-CRC effect, their mechanism was involving the control of the PI3K/Akt/NF-κB signaling pathway. What's more, the potential synergistic effect of the fat-soluble and water-soluble components found in this study provided a solid foundation for our deep understanding of how jujube can ameliorate CRC.

Insight into the self-assembly behavior of α-zein by multi-spectroscopic and molecular simulations: An example of combination with the main component of jujube peel pigments - Rutin.

Zein has been widely used as a kind of carrier material for its self-assembly capability, while the mechanism of this process is still elusive. Rutin, one of the flavonoids, has been confirmed as the main ingredient of pigments in jujube peels. In this work, the binding mechanism in the zein/rutin complexes has been systematically studied by using multi-spectroscopic methods and molecular simulations. Results have shown that the encapsulation efficiency of complexes has researched the maximum, 67.30 % ± 1.50 %, when the concentration of rutin is 60 µM. Furthermore, the spherical morphology of complexes has been provided by microstructure characterization. Multi-spectroscopic indicated that a static quenching, alongside strong affinity, occurred in the process of interaction. Hydrophobic interaction has been further proven as the main force in zein/rutin complexes from the results of molecular dynamics simulation. This work is vital to fully utilize zein for the delivery of bio-compounds.

Genome-wide identification of drought-responsive microRNAs and their target genes in Chinese jujube by deep sequencing.

BACKGROUND: MicroRNAs (miRNAs) are about 21 snucleotide (nt) long, non-coding RNAs that play an important role in plant abiotic stress responses. Chinese jujube is a native fruit tree in China, which is also an admittedly drought-resistant plant. But the drought-related miRNAs have little been reported in jujube. OBJECTIVE: To identify possibly drought-responsive microRNAs and their target genes in Chinese Jujube. METHODS: Twelve small RNA libraries were constructed from two jujube genotypes both drought treated and control samples with three replicates to identify known and novel miRNAs in Chinese Jujube, DESeq2 was used to identify expression pattern of miRNAs between drought treatment and control samples, TargetFinder program was used to predict potential target genes of conserved and novel miRNAs, RT-qPCR were used to analysis the expression levels of drought-related miRNAs and their potential targets. The RNA ligase-mediated RLM-5' RACE experiments were performed to validate predicted target genes of drought-related miRNAs. RESULTS: 43 known miRNAs and 431 novel miRNAs were identified in Chinese jujube. Expression analysis showed that 28 miRNAs were differential expressed under drought stress in jujube variety "Dongzao", including 21 up-regulated miRNAs and 7 down-regulated miRNAs, 61 miRNAs were differential expressed under drought stress in Chinese jujube variety "Zanhuangdazao", including 23 up-regulated miRNAs and 37 down-regulated miRNAs. Depend on miRNAs target prediction, functional annotation and expression analysis, we identified 9 drought-related miRNAs, and 7 target genes of 6 miRNAs were confirmed using the modified 5'-RACE method. Also, RT-qPCR analyses revealed that relative expression of those miRNAs and their targets have negative tendency. CONCLUSION: We identified 6 drought-related miRNAs by high-throughout sequencing and target gene annotation from Chinese jujube, and targets of those miRNAs were confirmed by the modified 5'-RACE method. These findings provide molecular evidence for enhancing drought tolerance in Chinese jujube and other plants.

Effects of dietary supplementation with selenium yeast and jujube powder on mitochondrial oxidative damage and apoptosis of chicken.

The main objective of this study was to explore the effects of dietary selenium yeast and jujube powder on mitochondrial oxidative damage and cell apoptosis of broilers during postmortem aging, chicken breasts of broilers fed diets supplemented with different concentrations of selenium yeast and jujube powder were used as research subjects. With the prolongation of postmortem aging time, the levels of reactive oxygen species (ROS), carbonyl content, mitochondrial permeability transition pore (MPTP) openness, and mitochondrial membrane permeability increased significantly (P < 0.05). The contents of the sulfhydryl, mitochondrial membrane potential, shear force, and cytochrome C (Cyt-c) reduction level decreased significantly (P < 0.05). The activity of Caspase-3 and Caspase-9 increased from 0 to 24 h postmortem but fell from 24 to 72 h postmortem. Compared with the control group, dietary selenium yeast and jujube powder significantly reduced mitochondrial oxidative damage. They greatly increased the shear force, mitochondrial membrane potential, and Cyt-c reduction levels (P < 0.05). Among them, the combination group of high-dose selenium yeast and jujube powder had more significant effects on ROS scavenging, reducing cell membrane permeability, protecting cell membrane integrity, and increasing Cyt-c reduction level (P < 0.05). In conclusion, cell apoptosis intensifies during the chicken breast's aging time, and muscle tenderness continues. Still, different doses of dietary selenium yeast and jujube powder can inhibit mitochondrial oxidation to various degrees. The combined group of selenium yeast and jujube powder with 0.6 mg·kg-1 has the best effect. This study is of great significance for applying natural antioxidant ingredients such as selenium yeast and jujube powder in the development and utilization of poultry feed.

Elucidation of the Reinforcing Spleen Effect of Jujube Fruits Based on Metabolomics and Intestinal Flora Analysis.

Jujube (Ziziphus jujuba Mill.) fruit (JF) is widely consumed as food in Asian countries due to its potential effects for human health. As a traditional Chinese medicine, JF is often used to treat anorexia, fatigue and loose stools caused by spleen deficiency syndromes in China, but the mechanism underlying this effect has not been thoroughly elucidated. In this study, a rat model of spleen deficiency syndromes was adopted to investigate the therapeutic effect of JF extract and its possible mechanism by metabolomics analyses of plasma and urine as well as the intestinal flora analysis. The results showed that the changes in plasma and urine metabolites caused by spleen deficiency were reversed after administration of JF, and these changed endogenous metabolites were mainly involved in retinol metabolism, pentose and glucuronate interconversions, nicotinate and niacinamide metabolism pathways. The 16S rDNA sequencing results showed that JF could regulate intestinal flora imbalance caused by spleen deficiency. The covariance analysis of intestinal flora structure and metabolome indicated that Aerococcus may be a candidate strain for predicting and treating the metabolic pathways of spleen deficiency and related disorders. In summary, it can be revealed that spleen deficiency, which alters metabolic profiles and the intestinal flora, could be alleviated effectively by JF extract.

Ziziphus spina-christi Leaf Extract Mitigates Mercuric Chloride-induced Cortical Damage in Rats.

BACKGROUND: Mercuric chloride (HgCl2) severely impairs the central nervous system when humans are exposed to it. AIMS: We investigated the neuroprotective efficiency of Ziziphus spina-christi leaf extract (ZSCLE) on HgCl2-mediated cortical deficits. METHODS: Twenty-eight rats were distributed equally into four groups: the control, ZSCLE-treated (300 mg/kg), HgCl2-treated (0.4 mg/kg), and ZSCLE+HgCl2-treated groups. Animals received their treatments for 28 days. RESULTS: Supplementation with ZSCLE after HgCl2 exposure prevented the deposition of mercury in the cortical slices. It also lowered malondialdehyde levels and nitrite and nitrate formation, elevated glutathione levels, activated its associated-antioxidant enzymes, glutathione reductase, and glutathione peroxidase, and upregulated the transcription of catalase and superoxide dismutase and their activities were accordingly increased. Moreover, ZSCLE activated the expression of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 when compared with the HgCl2 group. Notably, post-treatment with ZSCLE increased the activity of acetylcholinesterase and ameliorated the histopathological changes associated with HgCl2 exposure. Furthermore, ZSCLE blocked cortical inflammation, as observed by the lowered mRNA expression and protein levels of interleukin-1 beta and tumor necrosis factor-alpha, as well as decreased mRNA expression of inducible nitric oxide synthase. In addition, ZSCLE decreased neuron loss by preventing apoptosis in the cortical tissue upon HgCl2 intoxication. CONCLUSION: Based on the obtained findings, we suggest that ZSCLE supplementation could be applied as a neuroprotective agent to decrease neuron damage following HgCl2 toxicity.

Jujube metabolome selection determined the edible properties acquired during domestication.

Plants supply both food and medicinal compounds, which are ascribed to diverse metabolites produced by plants. However, studies on domestication-driven changes in the metabolome and genetic basis of bioactive molecules in perennial fruit trees are generally lacking. Here, we conducted multidimensional analyses revealing a singular domestication event involving the genomic and metabolomic selection of jujube trees (Ziziphus jujuba Mill.). The genomic selection for domesticated genes was highly enriched in metabolic pathways, including carbohydrates and specialized metabolism. Domesticated metabolome profiling indicated that 187 metabolites exhibited significant divergence as a result of directional selection. Malic acid was directly selected during domestication, and the simultaneous selection of specialized metabolites, including triterpenes, consequently lead to edible properties. Cyclopeptide alkaloids (CPAs) were specifically targeted for the divergence between dry and fresh cultivars. We identified 1080 significantly associated loci for 986 metabolites. Among them, 15 triterpenes were directly selected at six major loci, allowing the identification of a homologous cluster containing seven 2,3-oxidosqualene cyclases (OSCs). An OSC gene was found to contribute to the reduction in the content of triterpenes during domestication. The complete pathway for synthesizing ursolic acid was dissected by integration of the metabolome and transcriptome. Additionally, an N-methyltransferase involved in the biosynthesis of CPA and responsible for inter-cultivar content variation was identified. The present study promotes our understanding of the selection process of the global metabolome subsequent to fruit tree domestication and facilitates the genetic manipulation of specialized metabolites to enhance their edible traits.

Flavonoid Glycosides from Ziziphus jujuba var. inermis (Bunge) Rehder Seeds Inhibit α-Melanocyte-Stimulating Hormone-Mediated Melanogenesis.

Ziziphus jujuba extracts possess a broad spectrum of biological activities, such as antioxidant and anticancer activities in melanoma cancers. Nevertheless, the compounds contain high antioxidant capacities and anticancer activities in melanoma cells, shown to be effective in hyperpigmentation disorders, but whether flavonoid glycosides from Z. jujuba regulate anti-melanogenesis remains unclear. In this study, we evaluated the anti-melanogenic activity of five flavonoid glycosides from Z. jujuba var. inermis (Bunge) Rehder seeds, including jujuboside A (JUA), jujuboside B (JUB), epiceanothic acid (EPA), betulin (BTL), and 6'''-feruloylspinosin (FRS), in B16F10 melanoma cells and zebrafish larvae. According to our results, JUB, EPA, and FRS potently inhibited α-melanocyte-stimulating hormone (α-MSH)-induced melanogenesis and prevented hyperpigmentation in zebrafish larvae. In particular, under α-MSH-stimulated conditions, FRS most significantly inhibited α-MSH-induced intracellular and extracellular melanin content in B16F10 melanoma cells. Additionally, JUB, EPS, and FRS remarkably downregulated melanogenesis in α-MSH-treated zebrafish larvae, with no significant change in heart rate. Neither JUA nor BTA were effective in downregulating melanogenesis in B16F10 melanoma cells and zebrafish larvae. Furthermore, JUB, EPA, and FRS directly inhibited in vitro mushroom tyrosinase enzyme activity. JUB, EPA, and FRS also downregulated cyclic adenosine monophosphate (cAMP) levels and the phosphorylation of cAMP-response element-binding protein (CREB), and subsequent microphthalmia transcription factor (MITF) and tyrosinase expression. In conclusion, this study demonstrated that JUB, EPA, and FRS isolated from Z. jujuba var. inermis (Bunge) Rehder seeds exhibit potent anti-melanogenic properties by inhibition of the cAMP-CERB-MITF axis and consequent tyrosinase activity.

Jujube witches' broom phytoplasma effectors SJP1 and SJP2 induce lateral bud outgrowth by repressing the ZjBRC1-controlled auxin efflux channel.

Comprehensively controlling phytoplasma-associated jujube witches' broom (JWB) disease is extremely challenging for the jujube industry. Although the pathogenesis of phytoplasma disease has been highlighted in many plant species, the release of lateral buds from dormancy under JWB phytoplasma infection has not been characterized in woody perennial jujube. Here, two 16SrV-B group phytoplasma effectors, SJP1 and SJP2, were experimentally determined to induce witches' broom with increased lateral branches. In vivo interaction and subcellular localization analyses showed that both SJP1 and SJP2 were translocated from the cytoplasm to the nucleus to target the CYC/TB1-TCP transcription factor ZjBRC1. The N- and C-terminal coiled-coil domains of SJP1 and SJP2 were required for the TCP-binding ability. ZjBRC1 bound directly to the auxin efflux carrier ZjPIN1c/3 promoters and down-regulated their expression to promote the accumulation of endogenous auxin indole-3-acetic acid in jujube calli. Furthermore, JWB phytoplasma infection suppressed ZjBRC1 accumulation and induced ZjPIN1c/3 expression to stimulate lateral bud outgrowth. Therefore, SJP1 and SJP2 stimulate lateral bud outgrowth, at least partly, by repressing the ZjBRC1-controlled auxin efflux channel in jujube, representing a potential strategy for comprehensive phytoplasma-associated disease control and a resource for gene editing breeding to create new cultivars with varying degrees of shoot branching.