Hepatocellular carcinoma:An analysis of the expression status of stress granules and their prognostic value

BACKGROUND Hepatocellular carcinoma(HCC)is a global popular malignant tumor,which is difficult to cure,and the current treatment is limited.AIM To analyze the impacts of stress granule(SG)genes on overall survival(OS),survival time,and prognosis in HCC.METHODS The combined The Cancer Genome Atlas-Liver Hepatocellular Carcinoma(TCGA-LIHC),GSE25097,and GSE36376 datasets were utilized to obtain genetic and clinical information.Optimal hub gene numbers and corresponding coefficients were determined using the Least absolute shrinkage and selection operator model approach,and genes for constructing risk scores and corresponding correlation coefficients were calculated according to multivariate Cox regression,respectively.The prognostic model’s receiver operating characteristic(ROC)curve was produced and plotted utilizing the time ROC software package.Nomogram models were constructed to predict the outcomes at 1,3,and 5-year OS prognostications with good prediction accuracy.RESULTS We identified seven SG genes(DDX1,DKC1,BICC1,HNRNPUL1,CNOT6,DYRK3,CCDC124)having a prognostic significance and developed a risk score model.The findings of Kaplan-Meier analysis indicated that the group with a high risk exhibited significantly reduced OS in comparison with those of the low-risk group(P<0.001).The nomogram model’s findings indicate a significant enhancement in the accuracy of OS prediction for individuals with HCC in the TCGA-HCC cohort.Gene Ontology and Gene Set Enrichment Analysis suggested that these SGs might be involved in the cell cycle,RNA editing,and other biological processes.CONCLUSION Based on the impact of SG genes on HCC prognosis,in the future,it will be used as a biomarker as well as a unique therapeutic target for the identification and treatment of HCC.

Reference genes for quantitative real-time PCR analysis and quantitative expression of P5CS in Agropyron mongolicum under drought stress

Reference genes, stably expressing in different tissues and cells, are commonly used as the references in expression analysis. Selecting the optimum reference gene is crucial to the success of experiments. In this study, the expression stabilities of nine common reference genes, including ACT2, 18 S r RNA, APRT, EF-1α, RNA POL II, TUBα, TUBβ, GAPDH and TLF of Agropyron mongolicum, were studied under drought condition. Among them, 18 S r RNA was found to be the most optimum reference gene under drought stress by the analyzing of ge Norm and Norm Finder software. Quantitative expression levels of P5 CS using 18 S r RNA as the reference gene, and proline contents under drought stress in A. mongolicum were further operated, and we found the expression level of P5 CS gene and proline content had a significantly positive relationship（R^2=0.7763, P〈0.05）. This study established and validated 18 S r RNA as the reference genes in A. mongolicum under drought stress, providing a powerful tool for the quantitative expression analysis of drought genes in A. mongolicum.

Alleviation of Drought Stress in Arabidopsis thaliana by 17β-Estradiol Application

Animal steroidal hormones, including estrogens, are being introduced into the agricultural soil and water supply from increased pharmaceutical and farm waste. Considering the current levels of xenoestrogen contamination of plant environments in view of the climate change induced drought conditions, this study was designed to understand the effect of estradiol (ES) application on Arabidopsis drought stress responses. Estradiol treatment (10 nM, 100 nM) of plants subjected to drought stress conditions by withholding water for 7 days resulted in increased tolerance to drought stress reflected in the significantly higher plant survival rates of 74% and 78%, respectively compared to control plants’ survival rates of 36% (no treatment) and 40% (mock treatment). Estradiol application significantly increased the content of glutathione, proline and H2O2 and significantly enhanced the transcription of the stress responsive genes GSTU3, GER5, HSP101, and HSP70b. A high concentration of ES (10 μM) did not protect plants against drought stress and proved to be toxic. These results provide new insight into the effect of ES on drought-stress responses in Arabidopsis with possible practical agricultural applications regarding the effect of environmental estrogens on crop plants.

Effects of abiotic stress and hormones on the expressions of five13-CmLOXs and enzyme activity in oriental melon(Cucumis melo var.makuwa Makino)

Lipoxygenases（LOXs） are a group of non-heme,iron-containing enzymes and extensively involved in plant growth and development,ripening and senescence,stress responses,biosynthesis of regulatory molecules and defense reaction.In our previous study,18 LOXs in melon genome were screened and identified,and five 13-LOX genes（CmLOX08,CmLOX10,CmLOX12,CmLOX13 and CmLOX18） were predicted to locate in chloroplast.Phylogenetic analysis result showed that the five genes have high homology with jasmonic acid（JA） biosynthesis-related LOXs from other plants.In addition,promoter analysis revealed that motifs of the five genes participate in gene expression regulated by hormones and stresses.Therefore,we analyzed the expressions of the five genes and LOX activity in leaves of four-leaf stage seedlings of oriental melon cultivar Yumeiren under abiotic stress：wounding,cold,high temperature and hydrogen peroxide（H_2O_2）,and signal molecule treatments：methyl jasmonate（MeJA）,abscisic acid（ABA） and salicylic acid（SA）.Real time qPCR revealed that wounding and H_2O_2 induced the expressions of all the five genes.Only CmLOX08 was induced by cold while only CmLOX13 was suppressed by high temperature.ABA induced the expressions of CmLOXIO and CmLOX12 while inhibited CmLOX13 and CmLOX18.MeJA increased the 3 genes expressions except CmLOX08 and CmLOX13,whereas SA decreased the effect,apart from CmLOX12.All the abiotic stresses and signal molecules treatments increased the LOX activity in leaves of oriental melon.In summary,the results suggest that the five genes have diverse functions in abiotic stress and hormone responses,and might participate in defense response.The data generated in this study will be helpful in subcellular localization and transgenic experiment to understand their precise roles in plant defense response.

Characterization and expression analysis of genes encoding Taxol biosynthetic enzymes in Taxus spp.

Taxol(Paclitaxel),an important anticancer drug,is derived at very low yields from Taxus(yew)species that grow very slowly.In the present study,thirteen genes that encode enzymes involved in Taxol biosynthesis in Taxus spp.were analyzed with bioinformatics methods,and their expression levels in different tissues and after cold and hormone treatments were also analyzed.The results indicated that many cis-elements related to abiotic stresses and hormones were found in the promoter sequences of the 8 genes involved in Taxol biosynthesis.Moreover,the 13 enzymes encoded by the target genes were located in different organelles and had many phosphorylation sites in the response proteins.The 13 genes were expressed highly either in roots or in stems,with lower transcripts in needles,and they were highly expressed after treatment with cold,gibberellin,methyl jasmonate or coronatine,consistent with predictions based on the bioinformatics analysis.These results suggest that the factors such as hormones and abiotic stresses stimulate taxane biosynthesis in yews,providing an important way to sustainably generate taxanes from yew trees or their cell cultures to improve Taxol yields.

Heat Stress Related Gene Expression in Gossypium hirsutum L.

Abiotic stress is a major limiting factor to crop productivity,and heat stress is one of the important elements for reduced crop production.Plants respond to heat stress at molecular and cellular levels as well as physiological level.Heat stress alters expression patterns of numerous genes in plants.

GFP tracking transcriptional activity of endogenous p53: vector construction and application in genotoxicity detection

Objective: To establish a sensitive and specific system for genotoxicity detection in vivo. Methods: Endogenous p53 tracer vector p53RE was constructed by using green fluorescent protein (GFP) as a reporter to trace p53 transcriptional activity under the control of base SV40 early promoter. The tracer cells 3T3-REG were established by transfecting NIH3T3 cells with tracer vector and treated with ultraviolet, H2O2 and adriamycin to induce DNA damage and the subsequent endogenous p53 expression. The GFP expression and its green fluorescence in the tracer cells were observed and measured with fluorescent microscope and FACS. Results: The GFP expression increased rapidly after various treatment and reached the maximum 1 h later, and decreased gradually afterwards. FACS analysis showed that GFP expression in 3T3-REG tracer cells was consistent with the concentration of H2O2, while that in 3T3-SVG cells, which were transfected with control vector pSV-GFP. hardly increased in response to the treatment. Conclusion: GFP tracing p53 transcriptional activity is a sensitive and specific method for genotoxicity detection.

Expression Analysis of Proline Metabolism-related Genes From Halophyte Arabis stelleri under Osmotic Stress Conditions

Arabis stelleri var. japonica evidenced stronger osmotic stress tolerance than Arabidopsis thaliana. Using an A. thaliana microarray chip, we determined changes in the expression of approximately 2 800 genes between A. stelleri plants treated with 0.2 M mannitol versus mock-treated plants. The most significant changes in the gene expression patterns were in genes defining cellular components or in genes associated with the endomembrane system, stimulus response, stress response, chemical stimulus response, and defense response. The expression patterns of three de novo proline biosynthesis enzymes were evaluated in A. stelleri var. japonica seedlings treated with 0.2 M mannitol, 0.2 M sorbitol, and 0.2 M NaCI. The expression of At-pyrroline-5-carboxylate synthetase was not affected by NaCI stress but was similarly induced by mannitol and sorbitol. The proline dehydrogenase gene, which is known to be repressed by dehydration stress and induced by free L-proline, was induced at an early stage by mannitol treatment, but the level of proline dehydrogenase was increased later by treatment with both mannitol and NaCI. The level of free L-proline accumulation increased progressively in response to treatments with mannitol, sorbitol, and NaCI. Mannitol induced L-proline accumulation more rapidly than NaCI or sorbitol. These findings demonstrate that the osmotic tolerance of the novel halophyte, Arabis stelleri, is associated with the accumulation of L-proline.

A histomorphometric and molecular study on stress adaptability of freeze-dried bone allograft

Objective To Investigate stress adaptability of freeze-dried bone allograft.Methods Cortical and cancellous allograft were transplanted to each side of the midshaft diaphyseal ulna in two groups of 28 animals.The left transplanted allograft was free from fixation and bore a normal physiological lcad,while the right transplanted allograft was protected from loading by a simple external fixator and bore less load.Animals were sacrificed at the 2nd,4th,8th,16th week after transplantation and specimens were taken out for bone histomorphometry studies and analysis of collagen gene expression by in situ Cdna-Mrna hybridization.Results Labeled surface(LS)and bone mineral apposition rate(MAR)of the normally loaded graft-host bone interface were significantly higher than that of the less loaded side at the 4th,8th,16th week after transplantation.Parameters reflecting the internal repair process of the allograft,such as LS in cortical and cancellous bone or MAR in cortical bone of the normally loaded side were significantly higher than those of the less loaded side at the 16th week after transplantation.The result of in situ hybridization indicated that more osteoblast-like cells expressing the type Ⅰ collagen gene were found in the interface or interior of normally loaded grafts.Conclusion The stimulus of physiologic load can accelerate the early union of allograft-host bone interface and later new bone creep substitution to the necrotic allograft.

Effects of plant growth-promoting rhizobacteria on the molecular responses of maize under drought and heat stresses: A review

Drought and heat are major environmental stresses that continually influence plant growth and development. Under field conditions, these stresses occur more frequently in combination than alone, which magnifies corresponding detrimental effects on the growth and productivity of agriculturally important crops. Plant responses to such abiotic stresses are quite complex and manifested in a range of developmental, molecular, and physiological modifications that lead either to stress sensitivity or tolerance/resistance. Maize (Zea mays L.) is known for its sensitivity to abiotic stresses, which often results in substantial loss in crop productivity. Bioaugmentation with plant growth-promoting rhizobacteria (PGPR) has the potential to mitigate the adverse effects of drought and heat stresses on plants. Hence, this is considered a promising and eco-friendly strategy to ensure sustainable and long-term maize production under adverse climatic conditions. These microorganisms possess various plant growth-promoting (PGP) characteristics that can induce drought and heat tolerance in maize plants by directly or indirectly influencing molecular, metabolic, and physiological stress responses of plants. This review aims to assess the current knowledge regarding the ability of PGPR to induce drought and heat stress tolerance in maize plants. Furthermore, the drought and heat stress-induced expression of drought and heat stress response genes for this crop is discussed with the mechanisms through which PGPR alter maize stress response gene expression.

Study on Toughening on Crack Prevention of Jointed Rock Masses with Different Pre-Stress Anchor Cables

The major reason of the failure of jointed rock-mass is the formation of the plastic zone near the crack tip of I-II mixed crack which leads to the growth, propagation of the branched crack under load condition, rn the paper, the failure judgment of mini-plastic zone＇s displacement is derived by the Mises yielding rule. The anchor cable is simulated by the different link elements and inflicting pre-strains according to the difference of mechanism of the consolidated segment and free segment. The stress and strain fields near crack tip of twain collinear cracks of different angles and consolidated conditions are simulated by iso-parametric element with eight nodes. The iso-parametric element with eight nodes is degenerated to singular element at crick tip to simulate crack. It is shown that the mini plastic zone＇s displacement near the crack tip begins to increase, then decreases with the increase of the angle of the crack. The better consolidated condition is, the smaller the angle of crack tip is when the mini plastic zone＇s displacement near the crack tip arrives at the biggest value. The mini plastic zone＇s displacement near the crack Tip 2 is bigger than that near the crack Tip 3. The crack is easier to failure with the increase of load.

Genome-wide identification and characterization of phospholipase C gene family in cotton (Gossypium spp.)

Phospholipase C (PLC) are important regulatory enzymes involved in several lipid and Ca2+-dependent signaling pathways.Previous studies have elucidated the versatile roles of PLC genes in growth, development and stress responses of many plants, however, the systematic analyses of PLC genes in the important fiber-producing plant, cotton, are still deficient. In this study,through genome-wide survey, we identified twelve phosphatidylinositol-specific PLC (PI-PLC) and nine non-specific PLC (NPC) genes in the allotetraploid upland cotton Gossypium hirsutum and nine PI-PLC and six NPC genes in two diploid cotton G. arboretum and G.raimondii, respectively. The PI-PLC and NPC genes of G. hirsutum showed close phylogenetic relationship with their homologous genes in the diploid cottons and Arabidopsis. Segmental and tandem duplication contributed greatly to the formation of the gene family. Expression profiling indicated that few of the PLC genes are constitutely expressed, whereas most of the PLC genes are preferentially expressed in specific tissues and abiotic stress conditions. Promoter analyses further implied that the expression of these PLC genes might be regulated by MYB transcription factors and different phytohormones.These results not only suggest an important role of phospholipase C members in cotton plant development and abiotic stress response but also provide good candidate targets for future molecular breeding of superior cotton cultivars.