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Ghrelin is a peptide hormone secreted by gastrointestinal tract which regulates multiple physiological processes such as appetite, metabolism, growth and gonad development in fish. In the present study, the effects of ghrelin on hybrid tilapia infected with Aeromonas hydrophila are elucidated. Juvenile hybrid tilapia fish (20.0 ± 5.0 g) were intraperitoneally injected with 0, 0.1, 1.0, or 10.0 ng/g ghrelin/body weight synthetic ghrelin alone or in combination with A. hydrophila (0.5 × 106 CFU). At 10 days post treatment, the survival rate in the group that received 1.0 ng/g ghrelin/body weight ghrelin in combination with A. hydrophila was higher (66.66%) than that of the Ah group (13.33%) that received A. hydrophila alone. In tilapia that received ghrelin injections, reactive oxygen species (ROS) levels tended to increase at 5 h, while injection of 10.0 ng/g ghrelin/body weight ghrelin resulted in a significant decrease in ROS levels at 10 h. No changes in serum immune or antioxidant-related indicators were observed in fish injected with A. hydrophila compared to controls. However, ghrelin injection decreased Albumin (ALB), glutathione peroxidase (GSH-Px), lysozyme (LZM) and superoxide dismutase (SOD). Histological analysis showed that ghrelin injection alleviated the pathological changes in liver and spleen caused by A. hydrophila infection. Overall, the expression of HSP70, IL-1β, and TGF-β in the liver tended to upregulate compared to the control. In the kidney, HSP70, IL-1β and TGF-β levels were increased, and TNF-α expression levels were decreased compared to the control. The HSP70 level in the spleen was decreased, and IL-1β, TGF-β, and TNF-α were expressed at significantly higher levels in the spleen in the tilapia that received ghrelin injections. Taken together, our results indicate that injection with 1.0 ng/g ghrelin/body weight ghrelin may effectively protect juvenile hybrid tilapia against A. hydrophila infection by improving hematological indicators, maintaining normal histology and regulating cytokine gene expression.

The juvenile shoots of Phyllostachys edulis have been used as a food source for thousands of years, and it is recognized as a potential source of nutraceuticals. However, its rapid senescence restricts bamboo production and consumption, and the underlying molecular mechanisms of rapid shoot senescence remain largely unclear. In the present study, transcriptome profiling was employed to investigate the molecular regulation of postharvest senescence in shoots, along with physiological assays and anatomical dissections. Results revealed a distinct shift in expression postharvest, specifically transitions from cellular division and differentiation to the relocation of nutrients and programmed cell death. A number of regulatory and signaling factors were induced during postharvest senescence. Moreover, transcription factors, including NAM, ATAF and CUC (NAC) transcription factors, basic helix–loop–helix transcription factors, basic region/leucine zipper transcription factors, MYB transcription factors and WRKY transcription factors, were critical for shoot postharvest senescence, of which NACs were the most abundant. PheNAP2 and PheNAP3 were induced in postharvest shoots and found to promote leaf senescence in Arabidopsis by inducing the expression of AtSAG12 and AtSAG113. PheNAP2 and PheNAP3 could both restore the stay-green Arabidopsis nap to the wild-type phenotype either under normal growth condition or under abscisic acid treatment. Collectively, these results suggest that PheNAPs may promote shoot senescence. These findings provide a systematic view of shoot senescence and will inform future studies on the underlying molecular mechanisms responsible for shoot degradation during storage.

To determine the role of melatonin in aging maize seeds (Zea mays L.), we investigated the physiological characteristics and performance analysis of the transcriptome after applying melatonin to maize seeds as a response to aging. In this study, we demonstrated that applying exogenous melatonin alleviated aging-induced oxidative damage, improved the activity of aging seeds, promoted growth of the germ and radicle, enhanced antioxidant enzyme activity, and reduced membrane lipid peroxidation. In addition, transcriptome sequencing revealed that various metabolic processes were induced by exogenous melatonin application in aging maize seeds, including hormone signal transduction, cellular processes, carbohydrate metabolism, secondary metabolites, and amino acid metabolism. In summary, the findings provide a more comprehensive understanding for analysing the protective effect of melatonin in aging maize seeds.

Bamboos (Bambusoideae) are fast-growing species due to their rapid growth rate and ability to reproduce annually via cloned buds produced on the rhizome. WUSCHEL-related homeobox (WOX) genes have been reported to regulate shoot apical meristem organization, lateral organ formation, cambium and vascular proliferation, and so on, but have rarely been studied in bamboos. In this study, the WOXs of both herbaceous bamboo species (12 OlaWOXs and nine RguWOXs) and woody bamboo species (18 GanWOXs, 27 PheWOXs, and 26 BamWOXs) were identified and categorized into three clades based on their phylogenetic relationship&mdash, ancient, intermediate, or WUS clade. Polyploidy is the major driver of the expansion of the bamboo WOX family. Eight conserved domains, besides the homeodomain, were identified by comparatively analyzing the WOXs of dicot and monocot species. Intensive purifying selection pressure in the coding region of specific domains explained the functional similarity of WOXs between different species. For Bambusoideae WOXs, polyploidy is the major driver of the expansion of the WOX family. Stronger purifying selection was found in orthologous WOXs of Bambusoideae, especially for WOX4s and WOX5s, which are conserved not only at the translational levels, but also at the genome level. Several conserved cis-acting elements were discovered at similar position in the promoters of the orthologous WOXs. For example, AP2/ERF protein-binding elements and B3 protein-binding elements were found in the promoters of the bamboo WOX4, while MYB protein-binding elements and Dof protein-binding elements were found in the promoters of bamboo WOX5, and MADS protein-binding sites was found in the promoters of bamboo WUS, WOX3, and WOX9. These conserved positions may play an important role in regulating the expression of bamboo WOXs. Our work provides insight into the origin and evolution of bamboo WOXs, and will facilitate functional investigations of the clonal propagation of bamboos.

Low water availability is a major abiotic factor limiting photosynthesis and the growth and yield of crops. Maize (Zea mays) is among the most drought-sensitive cereal crops. Herein, the physiological and proteomic changes of maize seedlings caused by polyethylene-glycol-induced water deficit were analyzed. The results showed that malondialdehyde and proline contents increased continuously in the treated seedlings. Soluble sugar content and superoxide dismutase activity were upregulated initially but became downregulated under prolonged water deficit. A total of 104 proteins were found to be differentially accumulated under water stress. The identified proteins were mainly involved in photosynthesis, carbohydrate metabolism, stress defense, energy production, and protein metabolism. Interestingly, substantial incongruence between protein and transcript levels was observed, indicating that gene expression in water-stressed maize seedlings is controlled by complex mechanisms. Finally, we propose a hypothetical model that includes the different molecular, physiological, and biochemical changes that occurred during the response and tolerance of maize seedlings to water deficiency. Our study provides valuable insight for further research into the overall mechanisms underlying drought response and tolerance in maize and other plants.

Hybridization is a common breeding technique that can improve germplasm through heterosis in aquaculture. However, the regulation of key gene expression, including the details of transcriptional level changes at the beginning of hybridization events, remains largely undefined, especially in teleosts. In this study, by interspecies crossing between two pure lines of Nile tilapia and blue tilapia, we obtained a hybrid tilapia population as a model to elucidate heterosis, and we traced the molecular outcomes of growth hormone (GH) expression and allele-specific expression (ASE) in hybrids. The hybrids display growth vigor compared to their parents in the 120-day growth trial. GH mRNA expression was uniquely expressed in the pituitary. Higher GH expression was found in the hybrid than the midparent value, in both males and females, showing a nonadditive pattern. We identified four single-nucleotide polymorphism sites between Nile tilapia and blue tilapia. Subsequently, by pyrosequencing, we found asymmetric allelic expression in hybrids with higher maternal allelic transcript ratios in both males and females. Fasting significantly increased GH expression in hybrids, but asymmetric allelic expression was not affected by feeding or fasting conditions. Finally, we identified cis and trans effects via overall expression and ASE values in the hybrid, which showed that the cis and trans effects promoted the expression of maternal subgenome in the hybrid, contributing to the expression superiority of GH in hybrid tilapia. Taken together, the results of our study first illustrated the concept of GH expression superiority and its formation mechanism in hybrid fish with growth vigor.

In natural environments, cyclic drought which consists of repeated drought-recovery cycles is considerably more common than a prolonged drought event. Two genotypes of Catalpa bungei with contrasting growth performances under semi-arid area were both exposed to cyclic drought and control (well-watered) conditions, and their morphological and physiological responses related to drought resistance were investigated. In both genotypes, the major growth traits were significantly suppressed by cyclic drought. In addition, the intrinsic water use efficiency ( WUE i ) of each genotype was significantly elevated upon re-watering and contributed to rapid growth recovery after severe drought. Both genotypes exhibited leaf anatomy adaptation and gas exchange adjustment to alleviate water losses under cyclic drought. Meanwhile, elevated abscisic acid (ABA) and jasmonic acid (JA) were detected. The contents of free proline, soluble sugars, and glutathione were also elevated at drought condition. These adaptations interactively promoted the drought resistance of each genotype. Most physiological responses related to drought resistance were more active in genotype 9-1, which exhibited better growth performance than genotype 1-3 under cyclic drought. Genotype 9-1 showed larger extent of adaptive changes in its leaf anatomy and root system compared with 1-3. At the early stage of cyclic drought, the inducement of ABA was more sensitive in genotype 9-1, whereas genotype-specific coordination among ABA, salicylic acid, and indole-3-acetic acid at the biosynthesis level was detected in 9-1 but not in 1-3. Such coordination contributed to the better stoma adjustment and drought avoidance in genotype 9-1. Leaf δ 13 C was higher in 9-1 than that in 1-3, indicating that the former had larger long-term WUE than the latter. The soluble sugar content was also high in genotype 9-1 under severe drought. These anatomical and physiological features of genotype 9-1 contributed to its enhanced drought avoidance and growth performance under cyclic drought, which are better than those of 1-3.

The aim of the present study was to investigate the effects of Ginseng polysaccharides (GPS) on natural killer (NK) cell cytotoxicity in immunosuppressed mice. Cyclophosphamide (Cy) was used to construct an immunosuppressed mouse model. The mice in each group were submitted to gavages with 200 or 400 mg/kg GPS every day for 10 days. Magnetic-activated cell sorting was used to isolate spleen NK cells, and the NK cell cytotoxicity, blood distribution, expression levels of perforin and granzyme, and the mRNA expression levels of interferon (IFN)-γ were detected. Compared with the normal control group, the cytotoxicity and proportion of NK cells in the blood, and the expression levels of perforin, granzyme and IFN-γ mRNA in the Cy model group were significantly reduced (P0.05). Compared with the normal control group, the cytotoxicity and proportion of NK cells in the whole blood, and the expression levels of perforin in the Cy + low-dose GPS and the Cy + high-dose GPS groups were significantly lower (P0.05). These results suggested that GPS promotes NK cell cytotoxicity in immunosuppressed mice by increasing the number of NK cells in the whole blood and upregulating the expression of perforin and granzyme. Thus, the present study investigated the molecular mechanism underlying NK cell activation by GPS, the research showed that GPS have a wide application prospects in the treatment of cancer and immunodeficiency diseases.

Nitric oxide (NO) is an important bioactive molecule that functions in regulating diverse abiotic stresses in plants, whereas its molecular mechanism remains obscure. In this study, treatment with 0.1 mM NO donor (sodium nitroprusside, SNP) significantly alleviated the inhibited growth induced by 15% polyethyleneglycol (PEG)-stimulated water deficiency (WD) for 3 days in maize seedlings, manifested by less decreased plant total fresh weight and dry weight. Comprehensive proteome analysis was further used to measure the expression profiles of leaf proteins of SNP-pretreated maize seedlings under WD conditions to explore the molecular mechanisms of NO-induced WD tolerance. Using 2-DE method, 135 protein spots showed significantly enhanced or reduced abundance, of which 102 spots were successfully identified MALDI-TOF/TOF MS. The identified protein species were associated with diverse functions, and most (52/83, 62.7%) of known protein species were related to photosynthetic processes. Compared to alone PEG treatment, the abundance of 25 identified protein species in SNP + PEG treatment were enhanced among the identified photosynthesis-related protein species. In addition, exogenous SNP application dramatically regulated chlorophyll α fluorescence kinetics e.g. the increase of maximum quantum yield of PSII (Fv/Fm), photosynthetic performance index (PI), and IP phase, whereas it remarkably reduced the polyphasic OJIP fluorescence transient, the accumulation of reactive oxygen species (H2O2 and O2•-) and malondialdehyde (MDA). These findings suggest that the NO-induced WD tolerance could be associated with improved photosynthetic capability in higher plants.

Many semi-arid ecosystems are simultaneously limited by soil water and nitrogen (N). We conducted a greenhouse experiment to address how N availability impacts drought-resistant traits of Catalpa bungei C. A. Mey at the physiological and molecular level. A factorial design was used, consisting of sufficient-N and deficient-N combined with moderate drought and well-watered conditions. Seedling biomass and major root parameters were significantly suppressed by drought under the deficient-N condition, whereas N application mitigated the inhibiting effects of drought on root growth, particularly that of fine roots with a diameter

Natural killer (NK) cells are innate immune cells that can be activated rapidly to target abnormal and virus-infected cells without prior sensitization. With significant advancements in cell biology technologies, many NK cell lines have been established. Among these cell lines, NK-92 cells are not only the most widely used but have also been approved for clinical applications. Additionally, chimeric antigen receptor-modified NK-92 cells (CAR-NK-92 cells) have shown strong antitumor effects. In this review, we summarize established human NK cell lines and their biological characteristics, and highlight the applications of NK-92 cells and CAR-NK-92 cells in tumor immunotherapy.