Parental legacy versus regulatory innovation in salt stress responsiveness of allopolyploid cotton (Gossypium) species.

Polyploidy provides an opportunity for evolutionary innovation and species diversification, especially under stressful conditions. In allopolyploids, the conditional dynamics of homoeologous gene expression can be either inherited from ancestral states pre-existing in the parental diploids or novel upon polyploidization, the latter potentially permitting a wider range of phenotypic responses to stresses. To gain insight into regulatory mechanisms underlying the diversity of salt resistance in Gossypium species, we compared global transcriptomic responses to modest salinity stress in two allotetraploid (AD-genome) cotton species, Gossypium hirsutum and G. mustelinum, relative to their model diploid progenitors (A-genome and D-genome). Multivariate and pairwise analyses of salt-responsive changes revealed a profound alteration of gene expression for about one third of the transcriptome. Transcriptional responses and associated functional implications of salt acclimation varied across species, as did species-specific coexpression modules among species and ploidy levels. Salt responsiveness in both allopolyploids was strongly biased toward the D-genome progenitor. A much lower level of transgressive downregulation was observed in the more salt-tolerant G. mustelinum than in the less tolerant G. hirsutum. By disentangling inherited effects from evolved responses, we show that expression biases that are not conditional upon salt stress approximately equally reflect parental legacy and regulatory novelty upon allopolyploidization, whereas stress-responsive biases are predominantly novel, or evolved, in allopolyploids. Overall, our work suggests that allopolyploid cottons acquired a wide range of stress response flexibility relative to their diploid ancestors, most likely mediated by complex suites of duplicated genes and regulatory factors.

Interplay between ARABIDOPSIS Gß and WRKY transcription factors differentiates environmental stress responses.

Different environmental stresses often evoke similar physiological disorders such as growth retardation; however, specific consequences reported among individual stresses indicate potential mechanisms to distinguish different stress types in plants. Here, we examined mechanisms to differentiate between stress types in Arabidopsis (Arabidopsis thaliana). Gene expression patterns recapitulating several abiotic stress responses suggested abscisic acid (ABA) as a mediator of the common stress response, while stress type-specific responses were related to metabolic adaptations. Transcriptome and metabolome analyses identified Arabidopsis Gß (AGB1) mediating the common stress-responsive genes and primary metabolisms under nitrogen excess. AGB1 regulated the expressions of multiple WRKY transcription factors. Gene Ontology and mutant analyses revealed different roles among WRKYs: WRKY40 is involved in ABA and common stress responses, while WRKY75 regulates metabolic processes. The AGB1-WRKY signaling module controlled developmental plasticity in roots under nitrogen excess. Signal transmission from AGB1 to a selective set of WRKYs would be essential to evoke unique responses to different types of stresses.

Exogenous Kinetin Modulates ROS Homeostasis to Affect Heat Tolerance in Rice Seedlings.

Heat stress caused by rapidly changing climate warming has become a serious threat to crop growth worldwide. Exogenous cytokinin (CK) kinetin (KT) has been shown to have positive effects in improving salt and drought tolerance in plants. However, the mechanism of KT in heat tolerance in rice is poorly understood. Here, we found that exogenously adequate application of KT improved the heat stress tolerance of rice seedlings, with the best effect observed when the application concentration was 10-9 M. In addition, exogenous application of 10-9 M KT promoted the expression of CK-responsive OsRR genes, reduced membrane damage and reactive oxygen species (ROS) accumulation in rice, and increased the activity of antioxidant enzymes. Meanwhile, exogenous 10-9 M KT treatment significantly enhanced the expression of antioxidant enzymes, heat activation, and defense-related genes. In conclusion, exogenous KT treatment regulates heat tolerance in rice seedlings by modulating the dynamic balance of ROS in plants under heat stress.

Salt-tolerance diversity in diploid and polyploid cotton (Gossypium) species.

The development of salt-tolerant genotypes is pivotal for the effective utilization of salinized land and to increase global crop productivity. Several cotton species comprise the most important source of textile fibers globally, and these are increasingly grown on marginal or increasingly saline agroecosystems. The allopolyploid cotton species also provide a model system for polyploid research, of relevance here because polyploidy was suggested to be associated with increased adaptation to stress. To evaluate the genetic variation of salt tolerance among cotton species, 17 diverse accessions of allopolyploid (AD-genome) and diploid (A- and D-genome) Gossypium were evaluated for a total of 29 morphological and physiological traits associated with salt tolerance. For most morphological and physiological traits, cotton accessions showed highly variable responses to 2 weeks of exposure to moderate (50 mm NaCl) and high (100 mm NaCl) hydroponic salinity treatments. Our results showed that the most salt-tolerant species were the allopolyploid Gossypium mustelinum from north-east Brazil, the D-genome diploid Gossypium klotzschianum from the Galapagos Islands, followed by the A-genome diploids of Africa and Asia. Generally, A-genome accessions outperformed D-genome cottons under salinity conditions. Allopolyploid accessions from either diploid genomic group did not show significant differences in salt tolerance, but they were more similar to one of the two progenitor lineages. Our findings demonstrate that allopolyploidy in itself need not be associated with increased salinity stress tolerance and provide information for using the secondary Gossypium gene pool to breed for improved salt tolerance.

NADPH-cytochrome P450 reductase potentially involved in indoxacarb resistance in Spodoptera litura.

NADPH-cytochrome P450 reductase (CPR) plays a central role in the metabolism of insecticides. Numerous studies have shown that CPR is associated with insecticide resistance in insect. In this study, two transcripts of Spodoptera litura CPR (SlCPR-X1 and SlCPR-X2) were identified and cloned, and the deduced protein of SlCPR-X1 contains all the conserved CPR structural features (N-terminal membrane anchor, FMN, FAD and NADP binding domains, FAD binding motif, and catalytic residues). However, no N-terminal member anchor and a shorter FMN binding region have been identified in the deduced protein of SlCPR-X2. The specific expression patterns showed that SlCPR-X1 and SlCPR-X2 were detected in all tested developmental stages and tissues, but highly expressed in third-, fourth-, and fifth-instar larvae, and in midgut and fat body. In addition, compared with the susceptible strain, SlCPR-X1 and SlCPR-X2 were up-regulated and more inducible when treated with indoxacarb in the indoxacarb-resistant strain. However, the relative expression, up-regulation and induction of SlCPR-X1 were all higher than those of SlCPR-X2 in the indoxacarb-resistant strain. Furthermore, RNA interference and baculovirus expression system combined with MTT cytotoxicity assay demonstrated that only SlCPR-X1 with the N-terminal membrane anchor as the major CPR potentially involved in S. litura indoxacarb resistance. The outcome of this study further expands our understanding of the important role of insect CPR in xenobiotics detoxification and resistance development, and CPR could be a potential target for insecticide resistance management mediated by RNAi or CRISPR/Cas.

[Biofilm Eradication Four-Step Strategy: Study of Using Self-Assembled Azithromycin/Rhamnolipid Nanoparticles for Removing Pseudomonas aeruginosa Biofilm].

OBJECTIVE: To investigate the in vitro eradicative effect of self-assembled azithromycin/rhamnolipid nanoparticles (AZI-RHL NPs) on P seudomonas aeruginosa ( P. aeruginosa) biofilm. METHODS: AZI-RHL NPs were prepared and characterized. The minimum inhibitory concentration (MIC) of AZI-RHL NPs on planktonic P. aeruginosa was measured by the broth microdilution method. The eradicative effect of AZI-RHL NPs on P. aeruginosa biofilm was evaluated via crystal violet staining and SYTO 9/PI live/dead staining. Fluorescence labeling was used to measure the eradicative effect of NPs on extracellular polymeric substances (EPS). In addition, crystal violet staining was performed to evaluate the inhibitory effect of AZI-RHL NPs on the adhesion of P. aeruginosa on human bronchial epithelial BEAS-2B cells. To investigate the ability of AZI-RHL NPs to penetrate mucus, the interaction between NPs and mucin was measured via particle size changes after co-incubation with mucin solution. RESULTS: The AZI-RHL NPs had a particle size of about 121 nm and were negatively charged on the surface, displaying a high encapsulation efficiency and a high drug loading capacity of 96.72% and 45.08% for AZI, respectively and 99.38% and 53.07% for RHL, respectively. The MIC of AZI-RHL NPs on planktonic P. aeruginosa was half of that of using AZI alone. AZI-RHL NPs displayed the capacity to effectively destroy the biofilm structure and remove the proteins and polysaccharides in EPS, eradicating biofilms in addition to reducing the survival rate of bacteria in the biofilm. AZI-RHL NPs were shown to have inhibited P. aeruginosa adhesion on BEAS-2B cells and prevented the residual bacteria from forming a new biofilm. There was no significant change in the particle size of NPs after co-incubation with mucin solution, indicating a weak interaction between NPs and mucin, and suggesting that NPs could penetrate the mucus and reach the P. aeruginosa infection sites. CONCLUSION: AZI-RHL NPs were able to effectively enhance the removal of P. aeruginosa biofilm through a four-step strategy of biofilm eradication, including penetrating the mucus, disintegrating the biofilm structure, killing the bacteria dispersed from biofilm, and preventing the adhesion of residual bacteria. We hope that this study will provide a replicable common strategy for the treatment of refractory infections caused by P. aeruginosa and other types of biofilms.

Comprehensive characterization and gene expression patterns of LBD gene family in Gossypium.

MAIN CONCLUSION: A comprehensive account of the LBD gene family of Gossypium was provided in this work. Expression analysis and functional characterization revealed that LBD genes might play different roles in G. hirsutum and G. barbadense. The Lateral Organ Boundaries Domain (LBD) proteins comprise a plant-specific transcription factor family, which plays crucial roles in physiological processes of plant growth, development, and stress tolerance. In the present work, a systematical analysis of LBD gene family from two allotetraploid cotton species, G. hirsutum and G. barbadense, together with their genomic donor species, G. arboreum and G. raimondii, was conducted. There were 131, 128, 62, and 68 LBDs identified in G. hirsutum, G. barbadense, G. arboreum and G. raimondii, respectively. The LBD proteins could be classified into two main classes, class I and class II, based on the structure of their lateral organ boundaries domain and traits of phylogenetic tree, and class I was further divided into five subgroups. The gene structure and motif composition analyses conducted in both G. hirsutum and G. barbadense revealed that LBD genes kept relatively conserved within the subfamilies. Synteny analysis suggested that segmental duplication acted as an important mechanism in expansion of the cotton LBD gene family. Cis-element analysis predicated the possible functions of LBD genes. Public RNA-seq data were investigated to analyze the expression patterns of cotton LBD genes in various tissues as well as gene expression under abiotic stress treatments. Furthermore, RT-qPCR results found that GhLBDs had various expression regulation under MeJA treatments. Expression analysis indicated the differential functions of cotton LBD genes in response to abiotic stress and hormones.

Shelf-life extension of grape (Pinot noir) by xanthan gum enriched with ascorbic and citric acid during cold temperature storage.

The detrimental health implications of chemical preservatives in fruits have necessitated exploitation of safe and natural alternatives such as edible gums. This work studied shelf-life extension in grape (Pinot noir) under cold storage by xanthan gum (XAN) coatings enriched with ascorbic acid (XANAS) and citric acid (XANCI). Standard scientific methods were used to examine some sensory (color, texture-resilience and hardness), enzyme, anthocyanine and antioxidant activities. Also, the reaction rate mechanism was examined through modeling of selected shelf-life indicators; color change, weight loss, and antioxidants. The results revealed that, Xanthan gum and its acid modified coatings significantly (p < 0.05) suppressed polyphenol oxidase, ascorbic acid oxidase, polymethyl etherase acitivies and maintained the structural integrity of the grape during the 21 days storage period. Weight loss (%) in the grape samples was 13.66 < 13.98 < 14.16 < 15.64 in the order XANAS < XANCI < XAN < CONTROL whilst ferric reducing antioxidant power (FRAP) activity was 150.23 > 143.18 > 136.49 > 104.5 mg/100 g AEAC corresponding to XAN > XANAS > XANCI > CONTROL. Significantly (p < 0.05) higher phytochemical contents were observed in the gum coatings compared to the control. Through statistical parameters such as the coefficient of determination (R 2), root mean square error (RMSE) and reduced Chi square (χ2), the second-order polynomial model predicted precisely the decomposition of color, weight loss and FRAP of grape. Color deterioration was attributed to changes in b* parameter as a result of phenolics and phytochemical decompositions resulting from enzymatic activities. Conclusively, acid modified xanthan gum coatings could preserve phytochemicals, color, antioxidant and textural properties of grape in cold temperature storage.

Genetic basis of heterosis for yield and yield components explored by QTL mapping across four genetic populations in upland cotton.

BACKGROUND: Quantitative trait loci (QTL) mapping provides a powerful tool to unravel the genetic bases of cotton yield and its components, as well as their heterosis. In the present study, the genetic basis underlying inbreeding depression and heterosis for yield and yield components of upland cotton was investigated in recombinant inbred line (RIL), immortalized F2 (IF2), and two backcross (BCF1) populations based on a high-density SNP linkage map across four environments. RESULTS: Significant inbreeding depression of fruit branches per plant (FB), boll numbers per plant (BN), seed cotton yield (SY), and lint yield (LY) in RIL population and high levels of heterosis for SY, LY, and boll weight (BW) in IF2 and two BCF1 populations were observed. A total of 285 QTLs were identified in the four related populations using a composite interval mapping approach. In the IF2 population, 26.60% partially dominant (PD) QTLs and 71.28% over-dominant (OD) QTLs were identified. In two BCF1 populations, 42.41% additive QTLs, 4.19% PD QTLs, and 53.40% OD QTLs were detected. For multi-environment analysis, phenotypic variances (PV) explained by e-QTLs were higher than those by m-QTLs in each of the populations, and the average PV of m-QTLs and e-QTLs explained by QTL × environment interactions occupied a considerable proportion of total PV in all seven datasets. CONCLUSIONS: At the single-locus level, the genetic bases of heterosis varied in different populations. Partial dominance and over-dominance were the main cause of heterosis in the IF2 population, while additive effects and over-dominance were the main genetic bases of heterosis in two BCF1 populations. In addition, the various genetic components to heterosis presented trait specificity. In the multi-environment model analysis, epistasis was a common feature of most loci associated with inbreeding depression and heterosis. Furthermore, the environment was a critical factor in the expression of these m-QTLs and e-QTLs. Altogether, additive effects, over-dominance, epistasis and environmental interactions all contributed to the heterosis of yield and its components in upland cotton, with over-dominance and epistasis more important than the others.

Hyperspectral imaging of liverwort Marchantia polymorpha identifies MpWRKY10 as a key regulator defining Foliar pigmentation patterns.

Foliar pigmentation patterns vary among plant species and growth conditions. In this study, we utilize hyperspectral imaging to assess foliar pigmentation in the bryophyte Marchantia polymorpha under nutrient stress and identify associated genetic factors. Using singular value decomposition (SVD) for feature selection, we quantitate color variations induced by deficiencies in phosphate, nitrate, magnesium, calcium, and iron. Pseudo-colored thallus images show that disrupting MpWRKY10 causes irregular pigmentation with auronidin accumulation. Transcriptomic profiling shows that MpWRKY10 regulates phenylpropanoid pathway enzymes and R2R3-MYB transcription factors during phosphate deficiency, with MpMYB14 upregulation preceding pigment accumulation. MpWRKY10 is downregulated in older, pigmented thalli under phosphate deficiency but maintained in young thalli, where it suppresses pigmentation genes. This downregulation is absent in pigmented thalli due to aging. Comparative transcriptome analysis suggests similar WRKY and MYB roles in nutrient response and pigmentation in red-leaf lettuce, alluding to conserved genetic factors controlling foliar pigmentation patterns under nutrient deficiency.

Microenvironment responsive charge-switchable nanoparticles act on biofilm eradication and virulence inhibition for chronic lung infection treatment.

Chronic pulmonary infection caused by Pseudomonas aeruginosa (P. aeruginosa) is a common lung disease with high mortality, posing severe threats to public health. Highly resistant biofilm and intrinsic resistance make P. aeruginosa hard to eradicate, while powerful virulence system of P. aeruginosa may give rise to the recurrence of infection and eventual failure of antibiotic therapy. To address these issues, infection-microenvironment responsive nanoparticles functioning on biofilm eradication and virulence inhibition were simply prepared by electrostatic complexation between dimethylmaleic anhydride (DA) modified negatively charged coating and epsilon-poly(l-lysine) derived cationic nanoparticles loaded with azithromycin (AZI) (DA-AZI NPs). Charge reversal responsive to acidic condition enabled DA-AZI NPs to successively penetrate through both mucus and biofilms, followed by targeting to P. aeruginosa and permeabilizing its outer/inner membrane. Then in situ released AZI, which was induced by the lipase-triggered NPs dissociation, could easily enter into bacteria to take effects. DA-AZI NPs exhibited enhanced eradication activity against P. aeruginosa biofilms with a decrease of >99.999% of bacterial colonies, as well as remarkable inhibitory effects on the production of virulence factors and bacteria re-adhesion & biofilm re-formation. In a chronic pulmonary infection model, nebulization of DA-AZI NPs into infected mice resulted in prolonged retention and increased accumulation of the NPs in the infected sites of the lungs. Moreover, they significantly reduced the burden of P. aeruginosa, effectively alleviating lung tissue damages and inflammation. Overall, the proposed DA-AZI NPs highlight an innovative strategy for treating chronic pulmonary infection.

In Vitro Bioactivities and Characterization of Mycelial Extracts from Different Strains of Phellinus igniarius (Agaricomycetes).

To fully utilize Phellinus igniarius fermentation mycelia, the present study investigated the in vitro antioxidant and α-amylase inhibitory properties of four Ph. igniarius strains. Organic solvents were used to extract fatty acids, phenolics, and flavonoids from the selected mushrooms. The composition and bioactivity of the extracts were evaluated. The lipid yield obtained using petroleum ether (7.1%) was higher than that obtained using 1:1 n-hex-ane+methanol (5.5%) or 2:1 dichloromethane+methanol (3.3%). The composition and relative content of saturated and unsaturated fatty acids in the petroleum ether extract were higher than those in other solvent extracts. Furthermore, ethyl acetate extracts had higher flavonoid and phenolic content and better antioxidant activity than other extracts; however, the 70% ethanol extracts had the best α-amylase inhibitory activity. The supernatant from the ethanol precipitation of aqueous and 1% (NH4)2C2O4 extracts could also be biocompound sources. This comparative study is the first highlighting the in vitro antioxidant and α-amylase inhibitory properties of the four strains of Ph. igniarius extracts prepared using different organic solvents, which makes the investigated species and extracts promising for biological application.

Antioxidant activity of Phellinus igniarius fermentation mycelia contributions of different solvent extractions and their inhibitory effect on α-amylase.

Phellinus spp. have historically been used as traditional medicines to treat various diseases owing to their antioxidant, antitumor, and antidiabetic activities. Polysaccharides exhibit antidiabetic activity. In the present study, the polysaccharide contents of four Phellinus strains were compared. Phellinus igniarius QB72 possessed higher polysaccharide production, stronger 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, and α-amylase inhibitory activity. The three polysaccharides were sequentially extracted and partially purified from the fermentation mycelia using hot water, 1 % (NH4)2C2O4, and 1.25 M NaOH. Hot water extract polysaccharides exhibited higher DPPH radical scavenging and strong inhibitory activity against α-amylase with an IC50 value of 6.84 ± 0.37 mg/mL. The carbohydrate content of A1 (approximately 17457 Da) was approximately 88.28 %. The α-amylase inhibitory activity IC50 was decreased (3.178 ± 0.187 mg/mL) after DEAE water elution. P. igniarius QB72 hot-water extracts of partially purified polysaccharides have great potential as α-amylase inhibitors in food and medication-assisted additives.

Comparative Transcriptome Analysis of Candidate Genes Associated with Mycelia Growth from a He-Ne Laser with Pulsed Light Mutant of Phellinus igniarius (Agaricomycetes).

A mutant Phellinus igniarius JQ9 with higher mycelial production was screened out by He-Ne laser with pulsed light irradiation, the mechanism underlying the higher mycelial production is still unknown. This study aims to obtain a comprehensive transcriptome assembly during the Ph. igniarius liquid fermentation and characterize the key genes associated with the mycelial growth and metabolism in Ph. igniarius JQ9. Our transcriptome data of Ph. iniarius JQ9 and the wild strain were obtained with the Illumina platform comparative transcriptome sequencing technology. The results showed that among all the 346 differentially expressed genes (DEGs), 245 were upregulated and 101 were downregulated. Candidate genes encoding endoglucanase, beta-glucosidase, cellulose 1,4-beta-cellobiosidase, glycoside hydrolase family 61 protein, were proposed to participate in the carbohydrate utilization from KEGG enrichment of the starch and sucrose metabolism pathways were upregulated in Ph. igniarius JQ9. In addition, three candidate genes encoding the laccase and another two candidate genes related with the cell growth were higher expressed in Ph. igniarius JQ9 than in the wild type of strain (CK). Analysis of these data revealed that increased these related carbohydrate metabolism candidate genes underlying one crucial way may cause the higher mycelia production.

Material sensitivity of patient-specific finite element models in the brace treatment of scoliosis.

Objectives: To study the mechanical sensitivity of different intervertebral disc and bone material parameters and ligaments under different force configurations and magnitudes in the scoliosis model. Methods: The finite element model of a 21-year-old female is built using computed tomography. Local range of motion testing and global bending simulations are performed for the model verification. Subsequently, Five force of different directions and configurations were applied to the finite element model applying the brace pad position. The material parameters of the model were related to different spinal flexibilities and included different material parameters of cortical bone, cancellous bone, nucleus and annulus. The virtual X-ray technique measured Cobb angle, thoracic Lordosis, and lumbar Kyphosis. Results: The difference in peak displacement is 9.28 mm, 19.99 mm, 27.06 mm, 43.99 mm, and 50.1 mm under five force configurations. The maximum Cobb angle difference due to material parameters are 4.7° and 6.2°, which are converted to thoracic and lumbar in-brace correction difference of 18% and 15.5%. The maximum difference in Kyphosis and Lordosis angle is 4.4° and 5.8°. The average thoracic and lumbar Cobb angle variation difference in intervertebral disc control group is larger than that in bone control group, while the average Kyphosis and Lordosis angle is inverse. The displacement distribution of models with or without ligaments is similar, with a peak displacement difference of 1.3 mm in C5. The peak stress occurred at the junction of the cortical bone and ribs. Conclusion: Spinal flexibility largely influences the treatment effect of the brace. The intervertebral disc has a greater effect on the Cobb angle, the bone has a greater effect on the Kyphosis and Lordosis angles, and the rotation is affected by both. Patient-specific material is the key to increasing accuracy in the personalized finite element model. This study provides a scientific basis for using controllable brace treatment for scoliosis.

Polysaccharides Derived from Mushrooms in Immune and Antitumor Activity: A Review.

Mushrooms are full of nutrition and have beneficial properties for human health. Polysaccharides are the main component of edible and medicinal mushrooms, especially ß-glucans, which have attracted much more attention for their complex structure and diverse biological activities. Among all the diverse medicinal activities of mushroom polysaccharides, antitumor and immune-enhancing activities are two excellent bioactivities that have much more potential and deserve application. Their bioactivities are highly dependent on their structural features, including molecular weight, monosaccharide composition, degree of branching, type and configuration of glycosidic bonds, substituent pattern, and chain conformation. This review summarizes the current method for obtaining polysaccharides from mushrooms, chemical characterizations of the structures and their roles in immune and antitumor activities. In addition, the methods for preparation of the polysaccharide derivatives and the potential medicinal clinical application are also discussed in this review, which may provide new guidance for mushroom polysaccharide development.

Exogenous Abscisic Acid Affects the Heat Tolerance of Rice Seedlings by Influencing the Accumulation of ROS.

Heat stress (HS) has become one of the major abiotic stresses that severely constrain rice growth. Abscisic acid (ABA) plays an important role in plant development and stress response. However, the effect of different concentrations of exogenous ABA on HS tolerance in rice still needs to be further elucidated. Here, we found that high concentrations of exogenous ABA increased HS damage in seedlings, whereas 10-12 M ABA treatment increased fresh and dry weight under HS relative to mock seedlings. Our further data showed that, in response to HS, 10-5 M, ABA-treated seedlings exhibited a lower chlorophyll content, as well as transcript levels of chlorophyll biosynthesis and antioxidant genes, and increased the accumulation of reactive oxygen species (ROS). In addition, the transcript abundance of some heat-, defense-, and ABA-related genes was downregulated on 10-5 M ABA-treated seedlings under HS. In conclusion, high concentrations of exogenous ABA reduced the HS tolerance of rice seedlings, and this negative effect could be achieved by regulating the accumulation of ROS, chlorophyll biosynthesis, and the transcription levels of key genes in seedlings under HS.

Fetal milieu-simulating hyaluronic acid-dopamine-chondroitin sulfate hydrogel promoting angiogenesis and hair regeneration for wound healing.

Wound regeneration with complete functions and skin appendages is still challenging in wound dressing application. Inspired by the efficient wound healing in the fetal environment, we developed a fetal milieu-mimicking hydrogel for accelerating wound healing simultaneously with hair follicle regeneration. To mimic the fetal extracellular matrix (ECM), which contains high content of glycosaminoglycans, hyaluronic acid (HA) and chondroitin sulfate (CS) were selected to fabricate hydrogels. Meanwhile, dopamine (DA) modification endowed hydrogels with satisfactory mechanical properties and multi-functions. The hydrogel encapsulated atorvastatin (ATV) and zinc citrate (ZnCit), namely HA-DA-CS/Zn-ATV, exhibited tissue adhesion, self-healing capacity, good biocompatibility, excellent anti-oxidant ability, high exudate absorption, and hemostasis property. In vitro results revealed that hydrogels exerted significant angiogenesis and hair follicle regeneration efficacy. In vivo results confirmed that hydrogels significantly promoted wound healing, and the closure ratio reached over 94 % after 14 days of hydrogels-treatment. The regenerated skin exhibited a complete epidermis, dense and ordered collagen. Furthermore, the number of neovessels and hair follicles in the HA-DA-CS/Zn-ATV group were 1.57- and 3.05-fold higher than those of the HA-DA-CS group. Thus, HA-DA-CS/Zn-ATV serves as multifunctional hydrogels for simulating the fetal milieu and achieving efficient skin reconstruction with hair follicle regrowth, exhibiting potential in clinical wound healing.

Comparative transcriptome analysis of the mechanism difference in heat stress response between indica rice cultivar "IR64" and japonica cultivar "Koshihikari" at the seedling stage.

Heat stress (HS) has become a major abiotic stress in rice, considering the frequency and intensity of extreme hot weather. There is an urgent need to explore the differences in molecular mechanisms of HS tolerance in different cultivars, especially in indica and japonica. In this study, we investigated the transcriptome information of IR64 (indica, IR) and Koshihikari (japonica, Kos) in response to HS at the seedling stage. From the differentially expressed genes (DEGs) consistently expressed at six time points, 599 DEGs were identified that were co-expressed in both cultivars, as well as 945 and 1,180 DEGs that were specifically expressed in IR and Kos, respectively. The results of GO and KEGG analysis showed two different HS response pathways for IR and Kos. IR specifically expressed DEGs were mainly enriched in chloroplast-related pathways, whereas Kos specifically expressed DEGs were mainly enriched in endoplasmic reticulum and mitochondria-related pathways. Meanwhile, we highlighted the importance of NO biosynthesis genes, especially nitrate reductase genes, in the HS response of IR based on protein-protein interaction networks. In addition, we found that heat shock proteins and heat shock factors play very important roles in both cultivars. This study not only provides new insights into the differences in HS responses between different subspecies of rice, but also lays the foundation for future research on molecular mechanisms and breeding of heat-tolerant cultivars.

Ultrasound Intensify the Flavonoid Production of the Willow Bracket Mushroom, Phellinus igniarius (Agaricomycetes), Fermentation Mycelia.

This research aimed to use a novel and effective ultrasound (US) approach for obtaining high bio-compound production, hence proposing strategies for boosting active ingredient biosynthesis. Furthermore, the US promotes several physiological effects on the relevant organelles in the cell, morphological effects on the structure of Phellinus igniarius mycelium, and increases the transfer of nutrients and metabolites. One suitable US condition for flavonoid fermentation was determined as once per day for 7-9 days at a frequency 22 + 40 kHz, power density 120 W/L, treated 10 min, treatment off time 7 s. The flavonoid content and production increased about 47.51% and 101.81%, respectively, compared with the untreated fermentation (P < 0.05). SEM showed that sonication changes the morphology and structure of Ph. igniarius mycelium; TEM reveals the ultrasonic treatment causes organelle aggregation. The ultrasound could affect the metabolism of the biosynthesis of the active ingredients.