A temporal gradient of cytonuclear coordination of chaperonins and chaperones during RuBisCo biogenesis in allopolyploid plants.

Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) has long been studied from many perspectives. As a multisubunit (large subunits [LSUs] and small subunits[SSUs]) protein encoded by genes residing in the chloroplast (rbcL) and nuclear (rbcS) genomes, RuBisCo also is a model for cytonuclear coevolution following allopolyploid speciation in plants. Here, we studied the genomic and transcriptional cytonuclear coordination of auxiliary chaperonin and chaperones that facilitate RuBisCo biogenesis across multiple natural and artificially synthesized plant allopolyploids. We found similar genomic and transcriptional cytonuclear responses, including respective paternal-to-maternal conversions and maternal homeologous biased expression, in chaperonin/chaperon-assisted folding and assembly of RuBisCo in different allopolyploids. One observation is about the temporally attenuated genomic and transcriptional cytonuclear evolutionary responses during early folding and later assembly process of RuBisCo biogenesis, which were established by long-term evolution and immediate onset of allopolyploidy, respectively. Our study not only points to the potential widespread and hitherto unrecognized features of cytonuclear evolution but also bears implications for the structural interaction interface between LSU and Cpn60 chaperonin and the functioning stage of the Raf2 chaperone.

Safflower CtFLS1-Induced Drought Tolerance by Stimulating the Accumulation of Flavonols and Anthocyanins in Arabidopsis thaliana.

Flavonol synthase gene (FLS) is a member of the 2-oxoglutarate-dependent dioxygenase (2-ODD) superfamily and plays an important role in plant flavonoids biosynthetic pathways. Safflower (Carthamus tinctorius L.), a key source of traditional Chinese medicine, is widely cultivated in China. Although the flavonoid biosynthetic pathway has been studied in several model species, it still remains to be explored in safflower. In this study, we aimed to elucidate the role of CtFLS1 gene in flavonoid biosynthesis and drought stress responses. The bioinformatics analysis on the CtFLS1 gene showed that it contains two FLS-specific motifs (PxxxIRxxxEQP and SxxTxLVP), suggesting its independent evolution. Further, the expression level of CtFLS1 in safflower showed a positive correlation with the accumulation level of total flavonoid content in four different flowering stages. In addition, CtFLS1-overexpression (OE) Arabidopsis plants significantly induced the expression levels of key genes involved in flavonol pathway. On the contrary, the expression of anthocyanin pathway-related genes and MYB transcription factors showed down-regulation. Furthermore, CtFLS1-OE plants promoted seed germination, as well as resistance to osmotic pressure and drought, and reduced sensitivity to ABA compared to mutant and wild-type plants. Moreover, CtFLS1 and CtANS1 were both subcellularly located at the cell membrane and nucleus; the yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assay showed that they interacted with each other at the cell membrane. Altogether, these findings suggest the positive role of CtFLS1 in alleviating drought stress by stimulating flavonols and anthocyanin accumulation in safflower.

Effects of homoeologous exchange on gene expression and alternative splicing in a newly formed allotetraploid wheat.

Homoeologous exchange (HE) is a major mechanism generating post-polyploidization genetic variation with important evolutionary consequences. However, the direct impacts of HE on gene expression and transcript diversity in allopolyploids without the intertwined evolutionary processes remain to be fully understood. Here, we analyzed high-throughput RNA-seq data of young leaves from plant groups of a synthetic allotetraploid wheat (AADD), which contained variable numbers of HEs. We aimed to investigate if and to which extent HE directly impacts gene expression and alternative splicing (AS). We found that HE impacts expression of genes located within HE regions primarily via a cis-acting dosage effect, which led to significant changes in the total expression level of homoeologous gene pairs, especially for homoeologs whose original expression was biased. In parallel, HE also influences expression of a large number of genes residing in non-HE regions by trans-regulation leading to convergent expression of homoeologs. Intriguingly, when taking the original relative homoeolog expression states into account, homoeolog pairs under trans-effect are more prone to manifesting a convergent response to the HEs whereas those under cis-regulation tended to show further exacerbated subgenome-biased expression. Moreover, HE-induced quantitative, largely individual-specific, changes of AS events were detected. Similar to homoeologous expression, homoeo-AS events under trans-effect were more responsive to HE. HE therefore exerts multifaceted immediate effects on gene expression and, to a less extent, on individualized transcript diversity in nascent allopolyploidy.

Homoeologous exchanges occur through intragenic recombination generating novel transcripts and proteins in wheat and other polyploids.

Recombination between homeologous chromosomes, also known as homeologous exchange (HE), plays a significant role in shaping genome structure and gene expression in interspecific hybrids and allopolyploids of several plant species. However, the molecular mechanisms that govern HEs are not well understood. Here, we studied HE events in the progeny of a nascent allotetraploid (genome AADD) derived from two diploid progenitors of hexaploid bread wheat using cytological and whole-genome sequence analyses. In total, 37 HEs were identified and HE junctions were mapped precisely. HEs exhibit typical patterns of homologous recombination hotspots, being biased toward low-copy, subtelomeric regions of chromosome arms and showing association with known recombination hotspot motifs. But, strikingly, while homologous recombination preferentially takes place upstream and downstream of coding regions, HEs are highly enriched within gene bodies, giving rise to novel recombinant transcripts, which in turn are predicted to generate new protein fusion variants. To test whether this is a widespread phenomenon, a dataset of high-resolution HE junctions was analyzed for allopolyploid Brassica, rice, Arabidopsis suecica, banana, and peanut. Intragenic recombination and formation of chimeric genes was detected in HEs of all species and was prominent in most of them. HE thus provides a mechanism for evolutionary novelty in transcript and protein sequences in nascent allopolyploids.

Genome-wide identification of members of the Skp1 family in almond (Prunus dulcis), cloning and expression characterization of PsdSSK1.

Skp1 (S-phase kinase-associated protein 1) is the core gene of SCF ubiquitin ligase, which mediates protein degradation, thereby regulating biological processes such as cell cycle progression, transcriptional regulation, and signal transduction. A variety of plant Skp1 gene family studies have been reported. However, the almond Skp1 gene family has not yet been studied. In this study, we identified 18 members of the Prunus dulcis PdSkp1 family that were unevenly distributed across six chromosomes of the almond genome. Phylogenetic tree analysis revealed that the PdSkp1 members can be divided into three groups: I, II, and III. PdSkp1 members in each subfamily have relatively conserved motif types and exon/intron numbers. There were three pairs of fragment duplication genes and one pair of tandem repeat genes, and their functions were highly evolutionarily conserved. Transcriptome data showed that PdSkp1 is expressed in almond flower tissues, and that its expression shows significant change during cross-pollination. Fluorescence quantitative results showed that eight PdSkp1 genes had different expression levels in five tissues of almond, i.e., branches, leaves, flower buds, flesh, and cores. In addition, we cloned a PsdSSK1 gene based on PdSkp1. The cloned PsdSSK1 showed the same protein sequence as PdSkp1-12. Results of qPCR and western blot analysis showed high expression of PsdSSK1 in almond pollen. In conclusion, we report the first clone of the key gene SSK1 that controls self-incompatibility in almonds. Our research lays a foundation for future functional research on PdSkp1 members, especially for exploring the mechanism of almond self-incompatibility. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-023-01278-9.

Genome-wide analysis and transcriptional reprogrammings of MYB superfamily revealed positive insights into abiotic stress responses and anthocyanin accumulation in Carthamus tinctorius L.

The MYB transcription factors comprise one of the largest superfamilies in plants that have been implicated in the regulation of plant-specific metabolites and responses to biotic and abiotic stresses. Here, we present the first comprehensive genome-wide analysis and functional characterization of the CtMYB family in Carthamus tinctorius. A total of 272 CtMYBs were identified and classified into 12 subgroups using comparative phylogenetic analysis with Arabidopsis and rice orthologs. The overview of conserved motifs, gene structures, and cis elements as well as the expression pattern of CtMYB genes indicated the diverse roles of these transcription factors during plant growth, regulation of secondary metabolites, and various abiotic stress responses. The subcellular localization and transactivation analysis of four CtMYB proteins indicated predominant localization in the nuclei with enhanced transcriptional activation in yeast. The expression of CtMYB63 induced with various abiotic stress conditions showed upregulation in its transcription level. In addition, the expression analysis of the core structural genes of anthocyanin biosynthetic pathway under drought and cold stress in CtMYB63 overexpressed transgenic lines also supports the notion of CtMYB63 transcriptional reprogramming in response to abiotic stress by upregulating the anthocyanin biosynthesis. Together, our findings revealed the underlying regulatory mechanism of CtMYB TF network involving enhanced cold and drought stress tolerance through activating the rapid biosynthesis of anthocyanin in C. tinctorius. This study also presents useful insights towards the establishment of new strategies for crop improvements.

Involvement of calcineurin/NFATc4 pathway in a single-prolonged stress-based rat model of post-traumatic stress disorder.

Post-traumatic stress disorder (PTSD) is a mental disease associated with the exposure of traumatic stress, and results in the structural and functional changes of hippocampus. Calcineurin (CaN), a calcium/calmodulin-regulated protein phosphatase ubiquitously expressed in brain, has a very important role in the fear extinction, neuronal structure and neuronal excitability. With CaN activation, its down target nuclear factor of activated T cells (NFATs) dephosphorylated and then translocated from the cytoplasm to the nucleus to affect neuronal function, resulting in the function changes of brain structure such as hippocampus. Increasing evidence has suggested that CaN/NFATs signaling are involved in the regulation of mental disorders like Alzheimer's disease, depression, while little is known about its effects on the molecular mechanisms on PTSD. This study seek to know the relationship between PTSD and CaN/NFATc4 pathway, and to detect whether CaN/NFATc4 pathway are involved in the hippocampus dysfunctions in a single-prolonged stress (SPS)-based rat model of PTSD. Our results have showed that after 4 days exposed to SPS, the protein expression of CaN up-regulated and the NFATc4 dephosphorylated and imported into the nucleus; while at the 7 and 14 day exposed to SPS, with the down-regulation of CaN, the expression of phosphorylate-NFATc4 increased. Our results show that CaN/NFATc4 pathway were involved in the development of PTSD model, which suggested that the changes of CaN/NFATc4 pathway may be one of the pathological molecular mechanism in the dysfunction of hippocampus in PTSD.

Synergistic Redox Modulation for High-Performance Nickel Oxide-Based Inverted Perovskite Solar Modules.

Nickel oxide (NiOx)-based inverted perovskite solar cells stand as promising candidates for advancing perovskite photovoltaics towards commercialization, leveraging their remarkable stability, scalability, and cost-effectiveness. However, the interfacial redox reaction between high-valence Ni4+ and perovskite, alongside the facile conversion of iodide in perovskite into I2, significantly deteriorates the performance and reproducibility of NiOx-based perovskite photovoltaics. Here, potassium borohydride (KBH4) is introduced as a dual-action reductant, which effectively avoids the Ni4+/perovskite interface reaction and mitigates the iodide-to-I2 oxidation within perovskite film. This synergistic redox modulation significantly suppresses nonradiative recombination and increases the carrier lifetime. As a result, an impressive power conversion efficiency of 24.17% for NiOx-based perovskite solar cells is achieved, and a record efficiency of 20.2% for NiOx-based perovskite solar modules fabricated under ambient conditions. Notably, when evaluated using the ISOS-L-2 standard protocol, the module retains 94% of its initial efficiency after 2000 h of continuous illumination under maximum power point at 65 °C in ambient air.

Metamifop as an estrogen-like chemical affects the pituitary-hypothalamic-gonadal (HPG) axis of female rice field eels (Monopterus albus).

Metamifop (MET) is a widely used herbicide. It is likely for it to enter water environment when utilized, thus potential impacts may be produced on aquatic animals. Little information is available about its effects on the endocrine system of fish to date. In the current study, female rice field eels (Monopterus albus) were exposed to different MET concentrations (0, 0.2, 0.4, 0.6, 0.8 mg L -1) for 96 h to examine the effect of MET on the hypothalamic-pituitary-gonadal (HPG) axis and sexual reversal. The results showed that high concentrations of MET exposure increased vitellogenin (VTG) levels in liver and plasma, but plasma sex hormone levels were not affected by MET exposure. MET exposure increased the expression of CYP19A1b and CYP17 that regulate sex hormone production in the brain, but the expression of genes (CYP19A1a, CYP17, FSHR, LHCGR, hsd11b2, 3ß-HSD) associated with sex hormone secretion in the ovary and the estrogen receptor genes (esr1, esr2a, esr2b) in the liver were all suppressed. In addition, the expression of sex-related gene (Dmrt1) was suppressed. This study revealed for the first time that MET has estrogen-like effects and has a strong interference with the expression of HPG axis genes. MET did not show the ability to promote the sexual reversal in M. albus, on the contrary, the genes expression showed that the occurrence of male pathway was inhibited.

Characterization of the WRKY gene family reveals its contribution to the adaptability of almond (Prunus dulcis).

Background: WRKY (WRKY DNA-binding domain) transcription factors an important gene family that widely regulates plant resistance to biological and abiotic stresses, such as drought, salt and ion stresses. However, research on the WRKY family in almond has not yet been reported. Almond is an economically important fruit tree in Xinjiang that have strong resistance to various stresses. Results: A total of 62 PdWRKY genes were identified (including six pairs of homologous genes), and the phylogenetic tree was divided into three groups according to the WRKY domain and zinc finger motifs. The members of each group had a significant number of conserved motifs and exons/introns distributed unevenly across eight chromosomes, as well as 24 pairs of fragment duplicates and nine pairs of tandem duplicates. Moreover, the synteny and Ka/Ks analyses of the WRKY genes among almond and distinct species provided more detailed evidence for PdWRKY genes evolution. The examination of different tissue expression patterns showed that PdWRKY genes have tissue-specific expression characteristics. The qRT-PCR results showed that PdWRKY genes participate in the resistance of almond to the effects of low-temperature, drought and salt stress and that the expression levels of these genes change over time, exhibiting spatiotemporal expression characteristics. It is worth noting that many genes play a significant role in low-temperature stress resistance. In addition, based on the conserved WRKY motif, 321 candidate target genes were identified as having functions in multiple pathways. Conclusions: We conducted systematic bioinformatics analysis and abiotic stress research on the WRKY gene family in almond, laying the foundation for future PdWRKY genes research and improvements to almond production and breeding.

Genome-Wide Analysis of the Almond AP2/ERF Superfamily and Its Functional Prediction during Dormancy in Response to Freezing Stress.

The AP2/ERF transcription factor family is one of the largest transcription factor families in plants and plays an important role in regulating plant growth and development and the response to biotic and abiotic stresses. However, there is no report on the AP2/ERF gene family in almond (Prunus dulcis). In this study, a total of 136 PdAP2/ERF genes were identified from the almond genome, and their protein physicochemical properties were analyzed. The PdAP2/ERF members were divided into five subgroups: AP2, RAV, ERF, DREB, and Soloist. The PdAP2/ERF members in each subgroup had conserved motif types and exon/intron numbers. PdAP2/ERFS members are distributed on eight chromosomes, with 22 pairs of segmental duplications and 28 pairs of tandem duplications. We further explored the colinear relationship between almond and Arabidopsis thaliana, Oryza sativa, Malus domestica, and Prunus persicaAP2/ERF genes and their evolution. The results of cis-acting elements showed that PdAP2/ERF members are widely involved in various processes, such as growth and development, hormone regulation, and stress response. The results based on transcriptome expression patterns showed that PdAP2/ERF genes had significant tissue-specific expression characteristics and were involved in the response of annual dormant branches of almond to low-temperature freezing stress. In addition, the fluorescence quantitative relative expression results of 13 representative PdAP2/ERF genes in four tissues of 'Wanfeng' almond and under six low-temperature freezing treatments of annual dormant branches were consistent with the transcriptome results. It is worth noting that the fluorescence quantitative expression level showed that the PdERF24 gene was extremely significant at -30 °C, suggesting that this gene may play an important role in the response of almond dormancy to ultralow temperature freezing stress. Finally, we identified 7424 and 6971 target genes based on AP2 and ERF/DREB DNA-binding sites, respectively. The GO and KEGG enrichment results showed that these target genes play important roles in protein function and multiple pathways. In summary, we conducted bioinformatics and expression pattern studies on PdAP2/ERF genes, including 13 PdAP2/ERF genes, and performed fluorescence quantitative analysis of annual dormant shoots under different low-temperature freezing stress treatments to understand the tolerance of almond dormancy to freezing stress and suggest future improvements.

Genome-Wide Identification and Analysis of the MADS-Box Gene Family in Almond Reveal Its Expression Features in Different Flowering Periods.

The MADS-box gene family is an important family of transcription factors involved in multiple processes, such as plant growth and development, stress, and in particular, flowering time and floral organ development. Almonds are the best-selling nuts in the international fruit trade, accounting for more than 50% of the world's dried fruit trade, and one of the main economic fruit trees in Kashgar, Xinjiang. In addition, almonds contain a variety of nutrients, such as protein and dietary fiber, which can supplement nutrients for people. They also have the functions of nourishing the yin and kidneys, improving eyesight, and strengthening the brain, and they can be applied to various diseases. However, there is no report on the MADS-box gene family in almond (Prunus dulcis). In this study, a total of 67 PdMADS genes distributed across 8 chromosomes were identified from the genome of almond 'Wanfeng'. The PdMADS members were divided into five subgroups-Mα, Mß, Mγ, Mδ, and MIKC-and the members in each subgroup had conserved motif types and exon and intron numbers. The number of exons of PdMADS members ranged from 1 to 20, and the number of introns ranged from 0 to 19. The number of exons and introns of different subfamily members varied greatly. The results of gene duplication analysis showed that the PdMADS members had 16 pairs of segmental duplications and 9 pairs of tandem duplications, so we further explored the relationship between the MADS-box gene members in almond and those in Arabidopsis thaliana, Oryza sativa, Malus domestica, and Prunus persica based on colinear genes and evolutionary selection pressure. The results of the cis-acting elements showed that the PdMADS members were extensively involved in a variety of processes, such as almond growth and development, hormone regulation, and stress response. In addition, the expression patterns of PdMADS members across six floral transcriptome samples from two almond cultivars, 'Wanfeng' and 'Nonpareil', had significant expression differences. Subsequently, the fluorescence quantitative expression levels of the 15 PdMADS genes were highly similar to the transcriptome expression patterns, and the gene expression levels increased in the samples at different flowering stages, indicating that the two almond cultivars expressed different PdMADS genes during the flowering process. It is worth noting that the difference in flowering time between 'Wanfeng' and 'Nonpareil' may be caused by the different expression activities of PdMADS47 and PdMADS16 during the dormancy period, resulting in different processes of vernalization. We identified a total of 13,515 target genes in the genome based on the MIKC DNA-binding sites. The GO and KEGG enrichment results showed that these target genes play important roles in protein function and multiple pathways. In summary, we conducted bioinformatics and expression pattern studies on the PdMADS gene family and investigated six flowering samples from two almond cultivars, the early-flowering 'Wanfeng' and late-flowering 'Nonpareil', for quantitative expression level identification. These findings lay a foundation for future in-depth studies on the mechanism of PdMADS gene regulation during flowering in different almond cultivars.

Spatial and Temporal Transcriptomic Heredity and Asymmetry in an Artificially Constructed Allotetraploid Wheat (AADD).

Polyploidy, or whole-genome duplication (WGD), often induces dramatic changes in gene expression due to "transcriptome shock. " However, questions remain about how allopolyploidy (the merging of multiple nuclear genomes in the same nucleus) affects gene expression within and across multiple tissues and developmental stages during the initial foundation of allopolyploid plants. Here, we systematically investigated the immediate effect of allopolyploidy on gene expression variation in an artificial allopolyploidy system consisting of a constructed allotetraploid wheat (AADD genome, accession AT2) and its diploid progenitors Triticum urartu and Aegilops tauschii. We performed comprehensive RNA sequencing of 81 samples from different genotypes, tissues, and developmental stages. First, we found that intrinsic interspecific differences between the diploid parents played a major role in establishing the expression architecture of the allopolyploid. Nonetheless, allopolyploidy per se also induced dramatic and asymmetric patterns of differential gene expression between the subgenomes, and genes from the D subgenome exhibited a more drastic response. Second, analysis of homoeolog expression bias (HEB) revealed that the D subgenome exhibited significant expression bias and that de novo-generated HEB was attributed mainly to asymmetrical differential gene expression. Homoeolog-specific expression (HSE) analyses showed that the cis-only regulatory pattern was predominant in AT2, reflecting significant divergence between the parents. Co-expression network analysis revealed that homoeolog expression connectivity (HEC) was significantly correlated with sequence divergence in cis elements between subgenomes. Interestingly, allopolyploidy-induced reconstruction of network modules was also associated with different HSE patterns. Finally, a transcriptome atlas of spike development demonstrated that the phenotypic similarity of AT2 to T. urartu may be attributed to the combination of relatively stable expression of A-subgenome genes and drastic downregulation of their D-subgenome homoeologs. These findings provide a broad, multidimensional characterization of allopolyploidy-induced transcriptomic responses and suggest that allopolyploidy can have immediate and complex regulatory effects on the expression of nuclear genes.

Antioxidant, Anti-Inflammatory, and Cytotoxic Properties and Chemical Compositions of Filipendula palmata (Pall.) Maxim.

Filipendula palmata (Pall.) Maxim. remains unexplored and underutilized resources with a high potential to improve human health. In this study, a new ursane-type triterpenoid, namely, 2α, 3ß-dihydroxyurs-12-en-28-aldehyde (compound 10), and other 23 known compounds were isolated. 5 triterpenoids (compounds 6, 8, and 10-12), 11 flavonoids (compounds 13-15 and 17-24), 6 phenolic compounds (compounds 1, 2, 4, 5, 9, and 16), 2 sterols (compounds 3 and 7) were isolated from the aqueous solution extract of the aerial parts of F. palmata. The structures of all compounds were elucidated by the use of extensive spectroscopic methods such as infrared spectroscopy (IR), high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), 1H-NMR, and 13C-NMR. The solvent extractions of ethyl acetate fraction were evaluated for antioxidant activities using DPPH (2, 2-diphenyl-1-picrylhydrazyl) and ABTS+ (2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) methods. The anti-inflammatory effects of the compounds were evaluated in lipopolysaccharide- (LPS-) stimulated RAW 264.7 macrophages. The extract cytotoxicity on the cancer cell lines MCF-7, HeLa, 4T1, and A549 was determined by MTT assay. As a result, compounds 10, 11, and 12 exhibited better antioxidant activity compared to the other compounds. Compounds 8-24 had different inhibitory effects on the release of NO, TNF-α, and IL-6 in LPS-stimulated RAW 264.7 cells. The new compound has shown a significant inhibiting effect on cancer cells, and the cell inhibition rate increased in a dose-dependent manner. Further research to elucidate the chemical compositions and pharmacological effects of F. palmata is of major importance towards the development and foundation of clinical application of the species.

Platycodon grandiflorum extract: chemical composition and whitening, antioxidant, and anti-inflammatory effects.

Whitening cosmetics have a large market scale and broad development prospects, while whitening products of traditional Chinese medicine have always been a research hotspot. In this study, the whitening active extract of Platycodon grandiflorum (PGE) was isolated and purified for the first time, and the whitening activity mechanism and chemical composition of PGE were elucidated. A total of 45 components were identified via high-performance liquid chromatography-mass spectrometry (HPLC-MS) analysis, including arbutin, syringin, chlorogenic acid, platycoside E, platycodin D3, baicalin, platycodin D, and luteolin. The scavenging rates of PGE toward DPPH and ABTS free radicals were 98.03% and 84.30%, respectively. The inhibition rate of PGE toward tyrosinase was up to 97.71%. The PGE had significant anti-inflammatory effects on RAW264.7 macrophages stimulated by lipopolysaccharide (LPS) and had significant inhibition effects on tyrosinase and melanin generation of B16F10 cells stimulated by α-MSH. The results showed that the PGE achieved a synergistic whitening effect by inhibiting the activation of oxygen free radicals on tyrosinase, antioxidation, anti-inflammatory effect, enzyme activity, and melanin generation. As a whitening agent extracted from natural plants, PGE has great potential in the research and development of plant whitening cosmetics, which lays a foundation for the further development and utilization of Platycodon grandiflorum resources and also provides a theoretical basis for the development of green and organic whitening cosmetics.

Structural, physicochemical and functional properties of Semen Ziziphi Spinosae protein.

Semen Ziziphi Spinosae (Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chou) is a functional food and a traditional Chinese medicine (TCM) in China. Herein, Semen Ziziphi Spinosae protein (SZSP) was prepared by an alkaline extraction and acid precipitation method, of which the structural, physicochemical, functional and emulsion properties were investigated. Results showed that SZSP contained an ideal amino acid composition. The structural properties of the proteins were characterized using Fourier transform infrared spectroscopy (FTIR), relative fluorescence and circular dichroism (CD) spectroscopy analysis. The electrophoresis profiles showed that the main molecular weight of the protein components was about 10-40 kDa and contained some glycoproteins. Differential scanning calorimetry analysis indicated that the denaturation temperature of SZSP was 110.5 °C. The functional properties showed that SZSP has good water and oil absorption capacity, high emulsifying ability and foaming stability. The overall results suggest that SZSP is a promising protein source for the functional food industry.

Extraction, purification, characterization, anticoagulant activity, and anticoagulant mechanism of polysaccharides from the heads of Hypomesus olidus.

The aim of this work was to extract, isolate, and purify polysaccharides from the heads of Hypomesus olidus and to evaluate their anticoagulant activities and anticoagulant mechanisms. Response surface methodology was used to optimize the extraction conditions for ultrasonic-assisted extraction of polysaccharides from the heads of Hypomesus olidus. The optimal extraction conditions consisted of ultrasonic power of 275 W, ultrasonic time of 50 min, and solid-liquid ratio of 5 ml/g, giving the yield of crude polysaccharides (GYT) of 7.73 ± 0.042%. Three polysaccharide fractions, GYT-1, GYT-2, and GYT-3 were purified from GYT by using DEAE-cellulose-52 column and Sephadex G-100 column for anticoagulant activities. The results showed that two doses (2 and 4 mg/ml) of GYT-1 and GYT-3 could significantly prolong (p < .01) in partial thromboplastin time (APTT) (2.19 and 2.37 times, 2.22 and 2.44 times, respectively) and thrombin time (TT) (2.39 and 2.46 times, 2.44 and 2.80 times, respectively) compared with normal control. In particular, GYT-3 had stronger anticoagulant activity than GYT-1, and it was composed of arabinose, fructose, glucose, and lactose with molar ratios of 0.595:1: 2.026:0.273. However, GYT-2 had no anticoagulant activity (p > .05). In addition, anticoagulation mechanism of polysaccharides from the heads of Hypomesus olidus (GYT-3) was evaluated. The results showed that the anticoagulant activity of GYT-3 was based on their binding with antithrombin AT-III. And the inhibitory effects of GYT-3 on factor IIa and Xa were related to the concentration of AT-III in plasma. This study may provide a new and promising anticoagulant drug.

Characterization, hypolipidemic and antioxidant activities of degraded polysaccharides from Ganoderma lucidum.

The aim of this work is to characterize the primary structure and physicochemical properties of natural polysaccharides (GLP) and degraded polysaccharides (GLPUD) from Ganoderma lucidum, and evaluate their hypolipidemic and antioxidant activities. The results of particle size distribution and scanning electron microscopy (SEM) showed that Ganoderma lucidum polysaccharides were effectively degraded by ultrasonic method. GLPUD was composed of the same monosaccharide units as GLP but with different molar ratios. Infrared spectra and NMR showed that the primary structure of polysaccharides had not been changed by ultrasonic degradation. Meanwhile, the thermal stability of polysaccharides increased after ultrasonic treatment. After administration by GLP and GLPUD four weeks, body weight, visceral index, atherosclerosis index (AI) and biochemical indicators in serum and in liver were determined. The results showed that GLPUD had stronger hypolipidemic and antioxidant activities than GLP. GLPUD was more effective than the GLP for reducing AI, total cholesterol (TC), triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C), raising high density lipoprotein (HDL-C) (p < 0.01), reducing malondialdehyde (MDA) content, as well as increasing the glutathione peroxidase (GSH-Px) in mice serum, increasing superoxide dismutase (SOD) activity and reducing MDA content in liver (p < 0.05 or p < 0.01). In addition, the histopathological observations of mice livers showed that GLPUD could significantly improve lipid metabolism disorder in hepatocytes. Thus, GLPUD might be tested as a more effective hypolipidemic drug.

The evolution of genomic and epigenomic features in two Pleurotus fungi.

Pleurotus tuoliensis (Bailinggu, designated Pt) and P. eryngii var. eryngii (Xingbaogu, designated Pe) are highly valued edible mushrooms. We report de novo assemblies of high-quality genomes for both mushrooms based on PacBio RS II sequencing and annotation of all identified genes. A comparative genomics analysis between Pt and Pe with P. ostreatus as an outgroup taxon revealed extensive genomic divergence between the two mushroom genomes primarily due to the rapid gain of taxon-specific genes and disruption of synteny in either taxon. The re-appraised phylogenetic relationship between Pt and Pe at the genome-wide level validates earlier proposals to designate Pt as an independent species. Variation of the identified wood-decay-related gene content can largely explain the variable adaptation and host specificity of the two mushrooms. On the basis of the two assembled genome sequences, methylomes and the regulatory roles of DNA methylation in gene expression were characterized and compared. The genome, methylome and transcriptome data of these two important mushrooms will provide valuable information for advancing our understanding of the evolution of Pleurotus and related genera and for facilitating genome- and epigenome-based strategies for mushroom breeding.

Zinc oxide nanoparticle exposure triggers different gene expression patterns in maize shoots and roots.

The potential impacts of environmentally accumulated zinc oxide nanoparticles (nZnOs) on plant growth have not been well studied. A transcriptome profile analysis of maize exposed to nZnOs showed that the genes in the shoots and roots responded differently. Although the number of differentially expressed genes (DEGs) in the roots was greater than that in the shoots, the number of up- or down-regulated genes in both the shoots and roots was similar. The enrichment of gene ontology (GO) terms was also significantly different in the shoots and roots. The "nitrogen compound metabolism" and "cellular component" terms were specifically and highly up-regulated in the nZnO-exposed roots, whereas the categories "cellular metabolic process", "primary metabolic process" and "secondary metabolic process" were down-regulated in the exposed roots only. Our results revealed the DEG response patterns in maize shoots and roots after nZnO exposure.