Evolution and function analysis of auxin response factors reveal the molecular basis of the developed root system of Zygophyllum xanthoxylum.

BACKGROUND: As a xerophytic shrub, forming developed root system dominated with lateral roots is one of the effective strategies for Zygophyllum xanthoxylum to adapt to desert habitat. However, the molecular mechanism of lateral root formation in Z. xanthoxylum is still unclear. Auxin response factors (ARFs) are a master family of transcription factors (TFs) in auxin-mediated biological processes including root growth and development. RESULTS: Here, to determine the relationship between ARFs and root system formation in Z. xanthoxylum, a total of 30 potential ZxARF genes were first identified, and their classifications, evolutionary relationships, duplication events and conserved domains were characterized. 107 ARF protein sequences from alga to higher plant species including Z. xanthoxylum are split into A, B, and C 3 Clades, consisting with previous studies. The comparative analysis of ARFs between xerophytes and mesophytes showed that A-ARFs of xerophytes expanded considerably more than that of mesophytes. Furthermore, in this Clade, ZxARF5b and ZxARF8b have lost the important B3 DNA-binding domain partly and completely, suggesting both two proteins may be more functional in activating transcription by dimerization with AUX/IAA repressors. qRT-PCR results showed that all A-ZxARFs are high expressed in the roots of Z. xanthoxylum, and they were significantly induced by drought stress. Among these A-ZxARFs, the over-expression assay showed that ZxARF7c and ZxARF7d play positive roles in lateral root formation. CONCLUSION: This study provided the first comprehensive overview of ZxARFs and highlighted the importance of A-ZxARFs in the lateral root development.

Genomic analysis reveals phylogeny of Zygophyllales and mechanism for water retention of a succulent xerophyte.

Revealing the genetic basis for stress-resistant traits in extremophile plants will yield important information for crop improvement. Zygophyllum xanthoxylum, an extant species of the ancient Mediterranean, is a succulent xerophyte that can maintain a favorable water status under desert habitats; however, the genetic basis of this adaptive trait is poorly understood. Furthermore, the phylogenetic position of Zygophyllales, to which Z. xanthoxylum belongs, remains controversial. In this study, we sequenced and assembled the chromosome-level genome of Z. xanthoxylum. Phylogenetic analysis showed that Zygophyllales and Myrtales form a separated taxon as a sister to the clade comprising fabids and malvids, clarifying the phylogenetic position of Zygophyllales at whole-genome scale. Analysis of genomic and transcriptomic data revealed multiple critical mechanisms underlying the efficient osmotic adjustment using Na+ and K+ as "cheap" osmolytes that Z. xanthoxylum has evolved through the expansion and synchronized expression of genes encoding key transporters/channels and their regulators involved in Na+/K+ uptake, transport, and compartmentation. It is worth noting that ZxCNGC1;1 (cyclic nucleotide-gated channels) and ZxCNGC1;2 constituted a previously undiscovered energy-saving pathway for Na+ uptake. Meanwhile, the core genes involved in biosynthesis of cuticular wax also featured an expansion and upregulated expression, contributing to the water retention capacity of Z. xanthoxylum under desert environments. Overall, these findings boost the understanding of evolutionary relationships of eudicots, illustrate the unique water retention mechanism in the succulent xerophyte that is distinct from glycophyte, and thus provide valuable genetic resources for the improvement of stress tolerance in crops and insights into the remediation of sodic lands.

Genetic Diversity and Phylogenetic Analysis of Zygophyllum loczyi in Northwest China's Deserts Based on the Resequencing of the Genome.

In order to study the genetics of local adaptation in all main deserts of northwest China, whole genomes of 169 individuals were resequenced, which covers 20 populations of Zygophyllum loczyi (Zygophyllales: Zygophylaceae). We describe more than 15 million single nucleotide polymorphisms and numerous InDels. The expected heterozygosity and PIC values associated with local adaptation varied significantly across biogeographic regions. Variation in environmental factors contributes largely to the population genetic structure of Z. loczyi. Bayesian analysis performed with STRUCTURE defined four genetic clusters, while the results of principle component analysis were similar. Our results shows that the Qaidam Desert group appears to be diverging into two branches characterized by significant geographic separation and gene flow with two neighboring deserts. Geological data assume that it is possible that the Taklamakan Desert was the original distribution site, and Z. loczyi could have migrated later on and expanded within other desert areas. The above findings provide insights into the processes involved in biogeography, phylogeny, and differentiation within the northwest deserts of China.

Mass spectrometry-based metabolite profiling reveals functional seasonal shifts in the metabolome of Zygophyllum dumosum Boiss and its relation to environmental conditions.

MAIN CONCLUSION: A multi-year study of perennial Z. dumosum shows a consistent seasonal pattern in the changes of petiole metabolism, involving mainly organic acids, polyols, phenylpropanoids, sulfate conjugates, and piperazines. GC-MS and UPLC-QTOF-MS-based metabolite profiling was performed on the petioles of the perennial desert shrub Zygophyllum dumosum Boiss (Zygophyllaceae). The petioles, which are physiologically functional throughout the year and, thus, exposed to seasonal rhythms, were collected every month for 3 years from their natural ecosystem on a southeast-facing slope. Results showed a clear multi-year pattern following seasonal successions, despite different climate conditions, i.e., rainy and drought years, throughout the research period. The metabolic pattern of change encompassed an increase in the central metabolites, including most polyols, e.g., stress-related D-pinitol, organic and sugar acids, and in the dominant specialized metabolites, which were tentatively identified as sulfate, flavonoid, and piperazine conjugates during the summer-autumn period, while significantly high levels of free amino acids were detected during the winter-spring period. In parallel, the levels of most sugars (including glucose and fructose) increased in the petioles at the flowering stage at the beginning of the spring, while most of the di- and tri-saccharides accumulated at the beginning of seed development (May-June). Analysis of the conserved seasonal metabolite pattern of change shows that metabolic events are mostly related to the stage of plant development and its interaction with the environment and less to environmental conditions per se.

Heterologous expression of Zygophyllum xanthoxylon zinc finger protein gene (ZxZF) enhances the tolerance of poplar photosynthetic function to drought stress.

The ZxZF transcription factor (TF) of Zygophyllum xanthoxylon (Bunge) Maxim, an extremely drought-resistant woody plant, is a C2H2 zinc finger protein. Studies have shown that C2H2 zinc finger proteins play important roles in activating stress-related genes and enhancing plant resistance. However, their function in regulating plant photosynthesis under drought stress is not well understood. Since poplar is an important greening and afforestation tree species, it is particularly important to cultivate excellent drought-tolerant varieties. The ZxZF transcription factor (TF) was heterogeneously expressed in Euroamerican poplar (Populus × euroameracana cl.'Bofengl') by genetic transformation. Based on the mechanism and potential function of poplar photosynthesis regulated by ZxZF under drought stress, transcriptomic and physiological determinations were used to reveal the important role of this gene in improving the drought resistance of poplar. The results showed that the overexpression of ZxZF TF in transgenic poplars could improve the inhibition of Calvin cycle by regulating stomatal opening and increasing the concentration of intercellular CO2. The chlorophyll content, photosynthetic performance index, and photochemical efficiency of transgenic lines under drought stress were significantly higher than those of the wild type (WT). The overexpression of ZxZF TFs could alleviate the degree of photoinhibition of photosystems II and I under drought stress and maintain the efficiency of light energy capture and the photosynthetic electron transport chain. The transcriptomic data also showed that differentially expressed genes between the transgenic poplar and WT under drought stress were primarily enriched in metabolic pathways related to photosynthesis, such as photosynthesis, photosynthesis-antenna protein, porphyrin and chlorophyll metabolism, and photosynthetic carbon fixation, and the downregulation of genes related to chlorophyll synthesis, photosynthetic electron transport and Calvin cycle were alleviated. In addition, the overexpression of ZxZF TF can alleviate the inhibition of NADH dehydrogenase-like (NDH) cyclic electron flow of the poplar NDH pathway under drought stress, which plays an important role in reducing the excess pressure of electrons on the photosynthetic electron transport chain and maintaining the normal photosynthetic electron transport. In summary, the overexpression of ZxZF TFs can effectively alleviate the inhibition of drought on the assimilation of carbon in poplar and have a positive impact on light energy capture, the orderly transport of photosynthetic electron transport chain and the integrity of the photosystem, which is highly significant to acheivean in-depth understanding of the function of ZxZF TFs. This also provides an important basis for the breeding of new transgenic poplar varieties.

Massive increases in C31 alkane on Zygophyllum xanthoxylum leaves contribute to its excellent abiotic stress tolerance.

BACKGROUND AND AIMS: Desert plants possess excellent water-conservation capacities to survive in extreme environments. Cuticular wax plays a pivotal role in reducing water loss through plant aerial surfaces. However, the role of cuticular wax in water retention by desert plants is poorly understood. METHODS: We investigated leaf epidermal morphology and wax composition of five desert shrubs from north-west China and characterized the wax morphology and composition for the typical xerophyte Zygophyllum xanthoxylum under salt, drought and heat treatments. Moreover, we examined leaf water loss and chlorophyll leaching of Z. xanthoxylum and analysed their relationships with wax composition under the above treatments. KEY RESULTS: The leaf epidermis of Z. xanthoxylum was densely covered by cuticular wax, whereas the other four desert shrubs had trichomes or cuticular folds in addition to cuticular wax. The total amount of cuticular wax on leaves of Z. xanthoxylum and Ammopiptanthus mongolicus was significantly higher than that of the other three shrubs. Strikingly, C31 alkane, the most abundant component, composed >71 % of total alkanes in Z. xanthoxylum, which was higher than for the other four shrubs studied here. Salt, drought and heat treatments resulted in significant increases in the amount of cuticular wax. Of these treatments, the combined drought plus 45 °C treatment led to the largest increase (107 %) in the total amount of cuticular wax, attributable primarily to an increase of 122 % in C31 alkane. Moreover, the proportion of C31 alkane within total alkanes remained >75 % in all the above treatments. Notably, the water loss and chlorophyll leaching were reduced, which was negatively correlated with C31 alkane content. CONCLUSION: Zygophyllum xanthoxylum could serve as a model desert plant for study of the function of cuticular wax in water retention because of its relatively uncomplicated leaf surface and because it accumulates C31 alkane massively to reduce cuticular permeability and resist abiotic stressors.

Physiological and transcriptomic analyses provide insight into thermotolerance in desert plant Zygophyllum xanthoxylum.

BACKGROUND: Heat stress has adverse effects on the growth and reproduction of plants. Zygophyllum xanthoxylum, a typical xerophyte, is a dominant species in the desert where summer temperatures are around 40 °C. However, the mechanism underlying the thermotolerance of Z. xanthoxylum remained unclear. RESULTS: Here, we characterized the acclimation of Z. xanthoxylum to heat using a combination of physiological measurements and transcriptional profiles under treatments at 40 °C and 45 °C, respectively. Strikingly, moderate high temperature (40 °C) led to an increase in photosynthetic capacity and superior plant performance, whereas severe high temperature (45 °C) was accompanied by reduced photosynthetic capacity and inhibited growth. Transcriptome profiling indicated that the differentially expressed genes (DEGs) were related to transcription factor activity, protein folding and photosynthesis under heat conditions. Furthermore, numerous genes encoding heat transcription shock factors (HSFs) and heat shock proteins (HSPs) were significantly up-regulated under heat treatments, which were correlated with thermotolerance of Z. xanthoxylum. Interestingly, the up-regulation of PSI and PSII genes and the down-regulation of chlorophyll catabolism genes likely contribute to improving plant performance of Z. xanthoxylum under moderate high temperature. CONCLUSIONS: We identified key genes associated with of thermotolerance and growth in Z. xanthoxylum, which provide significant insights into the regulatory mechanisms of thermotolerance and growth regulation in Z. xanthoxylum under high temperature conditions.

Zygo-Albuside A: New Saponin from Zygophyllum album L. with Significant Antioxidant, Anti-Inflammatory and Antiapoptotic Effects against Methotrexate-Induced Testicular Damage.

Chemical investigation of the crude extract of the aerial part of Zygophyllum album L. (Z. album) led to the isolation of a new saponin, Zygo-albuside A (7), together with seven known compounds, one of them (caffeic acid, compound 4) is reported in the genus for the first time. NMR (1D and 2D) and mass spectrometric analysis, including high-resolution mass spectrometry (HRMS), were utilized to set up the chemical structures of these compounds. The present biological study aimed to investigate the protective antioxidant, anti-inflammatory, and antiapoptotic activities of the crude extract from the aerial part of Z. album and two of its isolated compounds, rutin and the new saponin zygo-albuside A, against methotrexate (MTX)-induced testicular injury, considering the role of miRNA-29a. In all groups except for the normal control group, which received a mixture of distilled water and DMSO (2:1) as vehicle orally every day for ten days, testicular damage was induced on the fifth day by intraperitoneal administration of MTX at a single dose of 20 mg/kg. Histopathological examination showed that pre-treatment with the crude extract of Z. album, zygo-albuside A, or rutin reversed the testicular damage induced by MTX. In addition, biochemical analysis in the protected groups showed a decrease in malondialdehyde (MDA), interleukin-6 (IL-6) and IL-1ß, Bcl-2-associated-protein (Bax), and an increase in B-cell lymphoma 2 (Bcl-2) protein, catalase (CAT), superoxide dismutase (SOD) in the testis, along with an increase in serum testosterone levels compared with the unprotected (positive control) group. The mRNA expression levels of nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α), p53, and miRNA-29a were downregulated in the testicular tissues of the protected groups compared with the unprotected group. In conclusion, the study provides sufficient evidence that Z. album extract, and its isolated compounds, zygo-albuside A and rutin, could alleviate testicular damage caused by the chemotherapeutic agent MTX.

Genetic variation and molecular characterization of Zygophyllum coccineum L. ecotypes of the iron mining area of El-Wahat El-Bahariya in Egypt.

Remediation and mitigation processes can recover the ecosystems affected by mining operations. Zygophyllum coccineum L. is a native indigenous xerophyte that grows in Egypt's Western Desert, particularly around the iron mining ore deposits, and accumulates high rates of potentially toxic elements (PTEs) in its succulent leaves. The present study evaluated the genetic variation and molecular responses of Z. coccineum to heavy metal stressful conditions in three sites. Results revealed that Z. coccineum bioaccumulation capacity was greater than unity and varied amongst the three locations. In response to heavy metal toxicity, Z. coccineum plants boosted their antioxidative enzymes activity and glutathione levels as a tolerance strategy. Anatomically, a compact epidermis, a thick spongy mesophyll with water storage cells, and a thicker vascular system were observed. Protein electrophoretic analysis yielded 20 fragments with a polymorphism rate of 85%. The antioxidant genes (CAT: catalase, POD: peroxidase and GST: polyphenol oxidase) showed greater levels of expression. In addition, DNA-based molecular genetic diversity analyses using Start Codon Targeted (SCoT) and Inter Simple Sequence Repeat (ISSR) markers yielded 54 amplified fragments (i.e. 24 monomorphic and 30 polymorphic), with 12 unique fragments and a polymorphism rate of 55.5%. The greatest PIC values were recorded for SCoT-6 (0.36) and for both of the 14 A and 44 B ISSR primers (0.25). Diversity index (DI) of all SCoT and ISSR amplified primers was 0.23. The present findings reveal the distinct heavy metal's adaption attributes of Z. coccineum, indicating its improved survival in severely arid mining environments.

Determination of Therapeutic and Safety Effects of Zygophyllum coccineum Extract in Induced Inflammation in Rats.

Background: Z. coccineum is a facultative plant with many medicinal applications. This study examined the anti-inflammatory activity of Zygophyllum coccineum (Z. coccineum) in an arthritis animal model. Materials and Methods: Seventy-Six Wistar Albino rats of either sex randomly divided into six groups (12/each). The inflammation model was done using Complete Freund's Adjuvant in albino rats. The anti-inflammatory activities of the extract were estimated at different dose levels (15.6, 31, and 60 mg/kg) as well as upon using methotrexate (MTX) as a standard drug (0.3 mg/kg). Paw volume and arthritis index scores have been tested in all examined animals' treatments. Histological examination of joints was also performed. Flow cytometric studies were done to isolated osteoclasts. Cytokines assay as well as biochemical testing was done in the examined samples. Results. In vitro studies reported an IC50 of 15.6 µg/ml for Z. coccineum extract in lipoxygenase inhibition assay (L.O.X.). Moreover, it could be noticed that isorhamnetin-3-O-glucoside, tribuloside, and 7-acetoxy-4-methyl coumarin were the most common compounds in Z. coccineum extract separated using L.C.-ESI-TOF-M.S. (liquid chromatography-electrospray ionization ion-trap time-of-flight mass spectrometry). Microscopic examinations of synovial tissue and hind limb muscles revealed the effect of different doses of Z. coccineum extract on restoring chondrocytes and muscles structures. Osteoclast size and apoptotic rate examinations revealed the protective effect of Z. coccineum extract on osteoclast. The results upon induction of animals and upon treatment using of MTX significantly increased apoptotic rate of osteoclast compared to control, while using of 15.6 µg/ml. for Z. coccineum extract lead to recover regular apoptotic rate demonstrating the protective effect of the extract. Z. coccineum extract regulated the secretion of proinflammatory and anti-inflammatory cytokines. Biochemical tests indicated the safety of Z. coccineum extract on kidney and liver functions. Conclusion. Z. coccineum extract has efficient and safe anti-inflammatory potential in an induced rat model.

Overexpression of the Zygophyllum xanthoxylum Aquaporin, ZxPIP1;3, Promotes Plant Growth and Stress Tolerance.

Drought and salinity can result in cell dehydration and water unbalance in plants, which seriously diminish plant growth and development. Cellular water homeostasis maintained by aquaporin is one of the important strategies for plants to cope with these two stresses. In this study, a stress-induced aquaporin, ZxPIP1;3, belonging to the PIP1 subgroup, was identified from the succulent xerophyte Zygophyllum xanthoxylum. The subcellular localization showed that ZxPIP1;3-GFP was located in the plasma membrane. The overexpression of ZxPIP1;3 in Arabidopsis prompted plant growth under favorable condition. In addition, it also conferred salt and drought tolerance with better water status as well as less ion toxicity and membrane injury, which led to more efficient photosynthesis and improved growth vigor via inducing stress-related responsive genes. This study reveals the molecular mechanisms of xerophytes' stress tolerance and provides a valuable candidate that could be used in genetic engineering to improve crop growth and stress tolerance.

Phytochemical Profiling, In Vitro and In Silico Anti-Microbial and Anti-Cancer Activity Evaluations and Staph GyraseB and h-TOP-IIß Receptor-Docking Studies of Major Constituents of Zygophyllum coccineum L. Aqueous-Ethanolic Extract and Its Subsequent Fractions: An Approach to Validate Traditional Phytomedicinal Knowledge.

Zygophyllum coccineum, an edible halophytic plant, is part of the traditional medicine chest in the Mediterranean region for symptomatic relief of diabetes, hypertension, wound healing, burns, infections, and rheumatoid arthritis pain. The current study aimed to characterize Z. coccineum phytoconstituents, and the evaluations of the anti-microbial-biofilm, and anti-cancers bioactivities of the plant's mother liquor, i.e., aqueous-ethanolic extract, and its subsequent fractions. The in silico receptors interaction feasibility of Z. coccineum major constituents with Staph GyraseB, and human topoisomerase-IIß (h-TOP-IIß) were conducted to confirm the plant's anti-microbial and anti-cancer biological activities. Thirty-eight secondary metabolites of flavonoids, stilbene, phenolic acids, alkaloids, and coumarin classes identified by LC-ESI-TOF-MS spectrometric analysis, and tiliroside (kaempferol-3-O-(6''''-p-coumaroyl)-glucoside, 19.8%), zygophyloside-F (12.78%), zygophyloside-G (9.67%), and isorhamnetin-3-O-glucoside (4.75%) were identified as the major constituents. A superior biofilm obliteration activity established the minimum biofilm eradication concentration (MBEC) for the chloroform fraction at 3.9-15.63 µg/mL, as compared to the positive controls (15.63-31.25 µg/mL) against all the microbial strains that produced the biofilm under study, except the Aspergillus fumigatus. The aqueous-ethanolic extract showed cytotoxic effects with IC50 values at 3.47, 3.19, and 2.27 µg/mL against MCF-7, HCT-116, and HepG2 cell-lines, respectively, together with the inhibition of h-TOP-IIß with IC50 value at 45.05 ng/mL in comparison to its standard referral inhibitor (staurosporine, IC50, 135.33 ng/mL). This conclusively established the anti-cancer activity of the aqueous-ethanolic extract that also validated by in silico receptor-binding predicted energy levels and receptor-site docking feasibility of the major constituents of the plant's extract. The study helped to authenticate some of the traditional phytomedicinal properties of the anti-infectious nature of the plant.

ZxNHX1 indirectly participates in controlling K+ homeostasis in the xerophyte Zygophyllum xanthoxylum.

The succulent xerophyte Zygophyllum xanthoxylum (Bunge) Engl. can absorb Na+ from the soil as an osmoticum in order to resist osmotic stress. The tonoplast Na+/H+ antiporter ZxNHX1 is essential for maintaining the salt-accumulation characteristics of Z. xanthoxylum by compartmentalizing Na+ into vacuoles. Previous results revealed that the silencing of ZxNHX1 greatly decreased Na+ accumulation in Z. xanthoxylum under 50 mM NaCl due to the weakened compartmentalisation; in addition, K+ concentration also significantly reduced in ZxNHX1-RNAi lines. Yet, whether the reduction of K+ concentration was directly triggered by the silencing of ZxNHX1 remains unclear. In this study, the growth parameters and expression levels of ZxSOS1, ZxHKT1;1, ZxAKT1 and ZxSKOR were measured in wild-type and ZxNHX1-RNAi lines under control or -0.5 MPa osmotic stress. The results showed that the silencing of ZxNHX1 inhibited the plant growth, decreased Na+ concentration in leaves, reduced the transcript abundance of ZxSOS1 and dramatically increased that of ZxHKT1;1 in roots of Z. xanthoxylum under osmotic stress; whereas tissue K+ concentrations and the expression level of ZxSKOR displayed no significant variations, and the expression of ZxAKT1 were significantly reduced in ZxNHX1-RNAi lines under osmotic stress, compared with the wild type. These results suggest that in Z. xanthoxylum, ZxNHX1 can maintain the normal growth by compartmentalizing Na+ into vacuoles, and regulate the spatial distribution of Na+ indirectly by affecting the expressions of ZxSOS1 and ZxHKT1;1. Moreover, the silencing of ZxNHX1 is not the main reason that led to the reduction of K+ concentration in ZxNHX1-RNAi lines under 50 mM NaCl, and ZxNHX1 might be indirectly involved in regulating K+ homeostasis.

OPDA and ABA accumulation in Pb-stressed Zygophyllum fabago can be primed by salicylic acid and coincides with organ-specific differences in accumulation of phenolics.

Salicylic acid (SA) is a well-known priming agent that is widely used to protect plants against stressing agents, including heavy metals as Pb. A better understanding of the mechanisms that enable plants to counteract Pb toxicity would help to select strategies for land reclamation programs. Here we used a metallicolous population of Zygophyllum fabago to assess the extent to which SA pretreatment modulates Pb-induced changes in phenol metabolism and stress-related phytohormone levels in roots and leaves. Our data revealed that accumulation of different phytohormones, lignin, soluble and wall-bound phenolics as well as peroxidase (PRX) activity in Pb-stressed plants differed after SA-pretreatment. Exposure to Pb led to the induction of soluble and cell wall-bound PRX activities, particularly those involved in the oxidation of coniferyl alcohol and ferulic acid, while pretreatment with SA reduced the Pb-induced stimulation of PRX activities in roots but increased them in leaves. SA-treatment by itself induced accumulation of ABA and the JA-precursor 12-oxo-phytodienoic acid (OPDA) in the roots. Pb in turn inhibited these SA-induced effects with the exception of OPDA accumulation that was primed by the pretreatment. The SA treatment also induced accumulation of OPDA in leaves but suppressed the accumulation of JA-Ile although with relatively small absolute changes. Notably, Pb-induced accumulation of ABA was primed in the leaves of SA-pretreated plants. Together our data suggest that priming of OPDA accumulation in the roots and of ABA in the leaves by SA-pretreatment may play important regulatory roles, possibly via regulating PRX activities, for Pb stress in plants.

Edaphic factors determining the colonization of semiarid mine tailings by a ruderal shrub and two tree plant species: Implications for phytomanagement.

Phytomanagement has been considered a feasible technique to decrease the environmental risks associated to mine tailings and its implementation relies on a suitable plant species selection. The goal of this study was to identify the edaphic factors, including microbiology, affecting the establishment of plant species with contrasting growth patterns during the phytomanagement of mine tailings. For this purpose, a comprehensive rhizosphere characterization was performed in an early ruderal colonizer, Zygophyllum fabago and two late successional tree species, Pinus halepensis and Tetraclinis articulata, growing at a mine tailings pile in southeast Spain. The neutral pH of the tailings determined low 0.01 M CaCl2 metal extractable concentrations (e.g. <10 µg kg-1 Pb and Cd). Thus, other soil properties different from metal concentrations resulted more determining to explain plant establishment. Results revealed that Z. fabago selectively colonized tailings patches characterized by high salinity (3.5 dS m-1) and high silt percentages (42%), showing a specific halotolerant rhizospheric microbial composition, such as the bacterial Sphingomonadales and Cytophagales orders and the fungal Pleosporales and Hyprocreales orders. The two tree species grew at moderate salinity areas of the tailings pile (1.7 dS m-1) with high sand percentages (85%), where Actinomycetales was the most abundant bacterial order (>10% abundance). The contrasting mycorrhizal behaviour of both tree species (ectomycorrhizal for P. halepensis and endomycorrhizal for T. articulata) could explain the differences found between their fungal rhizospheric composition. In terms of phytomanagement, the selective plant species colonization following specific soil patches at mine tailings would increase their biodiversity and resilience against environmental stressors.

Effect of phosphorus efficiency on elemental stoichiometry of two shrubs.

Phosphorus (P) is an important nutrient that can restrict plant growth. However, the influence of P deficiency on elemental homeostasis and application of the growth rate hypothesis in higher plants remain to be assessed. Two shrubs, Zygophyllum xanthoxylum and Nitraria tangutorum, were used as experiment material and subjected to five P addition treatments: 0, 17.5, 35.0, 52.5 and 70.0 mg P·kg-1 soil. The biomass and relative growth rate of Z. xanthoxylum did not change with altered P supply. There was no significant difference in P concentration among the treatments for Z. xanthoxylum, but N. tangutorum showed an upward trend. The P stoichiometric homeostasis of Z. xanthoxylum was higher than that of N. tangutorum. For Z. xanthoxylum, available P in the rhizosphere improved significantly under extreme P deficiency conditions, and P concentrations in all treatments were lower than in N. tangutorum, showing that Z. xanthoxylum had stronger P absorption and P utilization capacity. No relationships between growth rate and C:N:P ratios were found in Z. xanthoxylum. The strong P efficiency, and high and stable dry matter accumulation, are likely contributors in maintaining stoichiometric homeostasis. In addition, the relatively high biomass accumulation and high P utilization efficiency for Z. xanthoxylum does not support the growth rate hypothesis for this species.

Zygophyllum album leaves extract prevented hepatic fibrosis in rats, by reducing liver injury and suppressing oxidative stress, inflammation, apoptosis and the TGF-ß1/Smads signaling pathways. Exploring of bioactive compounds using HPLC-DAD-ESI-QTOF-MS/MS.

Zygophyllum album is traditionally used against many illnesses, such as liver disease. The present study investigated the bioactive compounds in methanol extract of Z. album (MEZA) using HPLC-DAD-ESI-QTOF-MS/MS and explored its possible antioxidative, anti-inflammatory, anti-apoptotic, and hepatoprotective effect. Twelve phenolic compounds were identified; isorhamnetin-3-O-rutinoside being the main one was the main composite (144.6 mg/100 g dm). Results showed that MEZA reduced significantly the biochemical markers (AST, ALT, LDH and ALP), and the hepatic oxidative stress indicators (MDA, PC, SOD, CAT, and GPx) in deltamethrin (DLM)-treated rats. Moreover, MEZA limited the inflammatory responses through downregulation of NF-κB gene, which suppressed the production of proinflammatory cytokines (TNF-α, IL-1ß, IL-6). Furthermore, Z. album reduced DLM-induced apoptosis by attenuating caspase 3 and p53 mRNA activation. MEZA treatment also alleviated upregulation of α-SMA, type I collagen, and TGF-ß1 mRNA in the liver. The possible antifibrotic effect of MEZA was clearly demonstrated by the histopathology examination, using Masson's Trichrome and Sirius Red stainings. Therefore, the current study suggested that the bioactive compounds of Z. album possessed antifibrotic effect against DLM-induced hepatic fibrosis, by protecting liver tissue, and inhibiting oxidative stress, inflammation, apoptosis and the TGF-ß1/Smads signaling pathways.

Complete Genome Sequence of Paenibacillus sp. JZ16, a Plant Growth Promoting Root Endophytic Bacterium of the Desert Halophyte Zygophyllum Simplex.

Paenibacillus sp. JZ16 is a gram-positive, rod-shaped, motile root endophytic bacterium of the pioneer desert halophytic plant Zygophyllum simplex. JZ16 was previously shown to promote salinity stress tolerance in Arabidopsis thaliana and possesses a highly motile phenotype on nutrient agar. JZ16 genome sequencing using PacBio generated 82,236 reads with a mean insert read length of 11,432 bp and an estimated genome coverage of 127X, resulting in a chromosome of 7,421,843 bp with a GC content of 49.25% encoding 6710 proteins, 8 rRNA operons, 117 ncRNAs and 73 tRNAs. Whole-genome sequencing analysis revealed a potentially new species for JZ16. Functional analysis revealed the presence of a number of enzymes involved in the breakdown of plant-based polymers. JZ16 could be of potential use in agricultural applications for promoting biotic and abiotic stress tolerance and for biotechnological processes (e.g., as biocatalysts for biofuel production). The culture-dependent collection of bacterial endophytes from desert plants combined with genome sequence mining provides new opportunities for industrial applications.

Zygophyllum album saponins prevent atherogenic effect induced by deltamethrin via attenuating arterial accumulation of native and oxidized LDL in rats.

The current study aimed to examine, for the first time, the relationship between exposure to deltamethrin (DLM) and atherogenic lipid profile disorders in adult Wistar rats, as well as, to verify the mechanism of the beneficial role of Zygophyllum album leaves extracts (ZALE). The experimental study was assessed using DLM (4 mg/kg b.w) either alone or co administered with ZALE (400 mg/kg b.w) orally for 90 days in rats. RP-HPLC-DAD-ESI-QTOF-MS was used to identify the bioactive metabolites present in ZALE. Plasmatic and aortic total cholesterol (TC), LDL-cholesterol (LDL-C), native LDL (LDL-apo B-100) and oxidized LDL (ox-LDL) were evaluated using auto-analyzer and a sandwich ELISA, respectively. The protein expressions of LDLR (native LDL receptor) and CD36 (Scavenger receptor class B) were evaluated in aorta or liver with a Western blot. The pathology has been confirmed with lipid stain (Oil Red O). Phytochemicals analysis revealed the presence of fifteen saponins in ZALE. Rats intoxicated with DLM revealed a significant increase in plasmatic and aortic lipid profile (TC, LDL-C, LDL-apo B-100 and ox-LDL), as well as, the concentration of the plasmatic cytokines include TNF-α, IL-2 and IL-6, compared to control. Hepatic native LDL and aortic CD36 receptor expression were increased in DLM treated group, however aortic LDL-R does not present any modification, when compared to control. The detected disturbances in lipid parameters were supported by Oil Red O applied. Due to their antioxidant activity, the bioactive compounds in ZALE as powerful agents able to prevent the pro-atherogenic effect observed in DLM-treated animals. These metabolites modulated most of inflammatory markers, prevented accumulation of lipid and lipoprotein biomarkers, regulated the major receptor regulators of hepatic cholesterol metabolism, as well as normalize lipid distribution in liver and aorta tissue.

Transcriptomic and metabolomic analysis reveals the role of CoA in the salt tolerance of Zygophyllum spp.

BACKGROUND: Zygophyllum is an important medicinal plant, with notable properties such as resistance to salt, alkali, and drought, as well as tolerance of poor soils and shifting sand. However, the response mechanism of Zygophyllum spp. to abiotic stess were rarely studied. RESULTS: Here, we aimed to explore the salt-tolerance genes of Zygophyllum plants by transcriptomic and metabolic approaches. We chose Z. brachypterum, Z. obliquum and Z. fabago to screen for salt tolerant and sensitive species. Cytological observation showed that both the stem and leaf of Z. brachypterum were significantly thicker than those of Z. fabago. Then, we treated these three species with different concentrations of NaCl, and found that Z. brachypterum exhibited the highest salt tolerance (ST), while Z. fabago was the most sensitive to salt (SS). With the increase of salt concentration, the CAT, SOD and POD activity, as well as proline and chlorophyll content in SS decreased significantly more than in ST. After salt treatment, the proportion of open stomata in ST decreased significantly more than in SS, although there was no significant difference in stomatal number between the two species. Transcriptomic analysis identified a total of 11 overlapping differentially expressed genes (DEGs) in the leaves and roots of the ST and SS species after salt stress. Two branched-chain-amino-acid aminotransferase (BCAT) genes among the 11 DEGs, which were significantly enriched in pantothenate and CoA biosynthesis, as well as the valine, leucine and isoleucine biosynthesis pathways, were confirmed to be significantly induced by salt stress through qRT-PCR. Furthermore, overlapping differentially abundant metabolites showed that the pantothenate and CoA biosynthesis pathways were significantly enriched after salt stress, which was consistent with the KEGG pathways enriched according to transcriptomics. CONCLUSIONS: In our study, transcriptomic and metabolomic analysis revealed that BCAT genes may affect the pantothenate and CoA biosynthesis pathway to regulate the salt tolerance of Zygophyllum species, which may constitute a newly identified signaling pathway through which plants respond to salt stress.