Canola Seedling Response to NaCl Stress – a Proteomic Approach

Salinity is a major abiotic stress worldwide, which causes a tremendous loss in the quality and quantity of agricultural products. In order to identify defense mechanisms to salinity-induced stress, a two-dimensional electrophoresis approach was used to investigate proteins achieved from canola cultivar ‘Option 500’ seedlings, after plants had been treated with NaCl. The 300 mmol NaCl treatment caused a significant decrease in fresh and dry weight as well as plant height and increment of proline content compared with control group. There were no significant changes in the quality of catalase and peroxidase activity. Out of 110 repeatable protein spots, 44 were registering change, according to induction factor index. 7 spots were recognized significant at 1% probability level statistically. These proteins were involved in energy production, ROS scavenging and suppressor, and those involved in photosynthesis. Production of chloroplastic fructose-bisphosphate aldolase enzyme along with carbohydrate metabolisms of Kelvin cycle and glycolysis increases under salinity condition. The amount of Cu/Zn SOD in chloroplast reduces in response to salinity which results from an increase in OH- radicals. Expression of photosynthesis proteins have been reduced probably as a consequence of the drop in osmotic pressure resulted from water scarcity and stomata closure, which reduces the availability of Co2

Salicylic acid and jasmonic acid alter physiological performance, assimilate mobilization and seed filling of soybean under salt stress

This research was conducted to investigate the morpho-physiological effects of salicylic acid and jasmonic acid on soybean performance and productivity under salinity. Leaf chlorophyll content index, carotenoids and anthocyanins content, photosystem II efficiency, relative water content, leaf area, leaf mass, specific leaf area, water use efficiency, seed filling duration, assimilate mobilization efficiency and seed mass decreased, but leaf temperature, specific leaf mass and electrolytic leakage of leaves increased with enhancing salinity. Salicylic acid improved leaf chlorophyll content index, anthocyanins content, leaf area, specific leaf area, water use efficiency, seed filing duration, assimilate mobilization efficiency and seed mass under both saline and non-saline conditions. The superior effects of salicylic acid on some traits such as maximum quantum yield of PSII, relative water content and leaf electrolytic leakage only occurred under different salinity levels. Jasmonic acid improved leaf mass, specific leaf mass, carotenoids content, relative water content, seed filling rate and reduced chlorophyll content index, leaf temperature, leaf area, specific leaf area, seed filling duration, assimilates mobilization efficiency and relative electrolytic leakage of soybean, with no significant effects on photosystem II efficiency and seed mass. Application of salicylic acid was, therefore, the superior treatment for enhancing physiological performance and seed mass of soybean plants under different salinity levels.</p

Salinity Tolerance in Canola: Insights from Proteomic Studies

Salinity considerably lowers crop yield worldwide. Production of salt stress-tolerant species will be essential to maintain the food supply in the coming decades. Brassicas, including various members of the family Brassicaceae, are very necessary sources of human food. Importantly, the key crop species that are members of the Brassicaceae family are genetically diverse and therefore their response reaction and adaptation to salinity varies greatly. Canola (Brassica napus L.) is commonly grown for edible oils and other uses such as biodiesel fuel production. Although most types of canola are identified as salt-resistant, plant yield and development are reduced significantly by rising salinity levels. In saline situations, the plant’s genome supports a range of physiological changes in some plant characteristics. Since the function of genes cannot indicate the exact condition of cells, proteomic approaches are emerged as methods to investigate the plant’s responses to stresses in the molecular levels. Exploring the proteome complements research at the genome and transcriptome level and helps elucidate the mechanism of salt tolerance in plants. Proteins are reliable indicators of salinity responses, as they are directly involved in forming the new phenotype providing adaptation to salinity. In this chapter, we review the response of the rapeseed proteome to salinity stress

In silico study of cis-acting elements revealing the plastid gene involved in oxidative phosphorylation are responsive to abiotic stresses

In order to study plastid gene response to abiotic stresses, the chloroplast genome of Brassica nigra and studied cis-acting elements were downloaded. All upstream regions of genes were determined and searched for the presence of known cis-acting elements. In these regions, 83 types of cis-acting elements were recognized. Unnamed elements (139 times), CAAT-box (96 times), and TATA-box (92 times) were in high frequency, whereas ATCC-motif, Box III, CE1, CE3, C-repeat/DRE, E2Fb, Gap-box, L-box, RY-element, and TGA-box occurred only one time. All of the cis-acting elements were grouped into seven categories, which 17% of cis-acting elements placed into abiotic and biotic-related elements. ARE (31 times) and LTR (21 times) elements were in high frequency. Among 42 genes with abiotic stress-related elements, 29 genes showed co-expression. Our results show that in response to anaerobic conditions and cold stress, chloroplast alters the genes-encoding proteins involved in complex I and V in oxidative phosphorylation pathway. This process, probably, is to reduce electron flow and convert NADPH and FADH forms to ATP form. These actions could decrease generating reactive oxygen species under stressful conditions. These findings could offer new insights on the strategies which chloroplasts take into account for preventing oxidative damage

The contribution of proteins with binding activity and specific metabolic pathways in tolerating abiotic stress by canola: An in silico study

Plants indicate different degrees of sensitivity and of tolerance upon encountering stressful conditions. In molecular level, plants respond in complex manner to stressful conditions. Obviously, the tolerant plants recruit molecular mechanisms that enable them to trigger appropriate reactions. To investigate molecular mechanisms involved in the response of Canola to stress conditions, two cultivars of Canola including Sarigol (as a sensitive cultivar) and Hyola308 (as a tolerant cultivar) were in silico studied based on their identified proteins with significantly expression changes under abiotic stresses. The results indicated that in Hyola308, the genes/proteins that are mostly involved in the response to stress and with functions related to binding activity are overrepresented. In term of Sarigol, the number of the genes/proteins involved in response to stress were the low and the most of its induced genes/proteins were involvement in catalytic and antioxidant activities. Five metabolic pathways including protein processing in endoplasmic reticulum, carbon fixation in photosynthetic organisms, endocytosis, spliceosome, and fructose and mannose metabolism were uniquely observed in Hyola308, which could be in relation with the tolerance of Hyola308. These pathways could be supposed as key metabolic pathways in Canola under stress. Finally, the genes UGD2, TPI, and AT3G09440 are introduced as potential candidate to be regarded in genetic engineering of Canola due to their core central roles in PPI network

Inhibitory effects of antagonistic bacteria inhabiting the rhizosphere of the sugarbeet plants, on Cercospora beticola Sacc., the causal agent of Cercospora leaf spot disease on sugarbeet

In the present study, the antagonistic capability of bacterial agents inhabiting the rhizosphere of sugarbeet plants were evaluated against Cercospora beticola Sacc. under laboratory and greenhouse conditions. After preliminary screening using the dual culture method, 14 strains with higher antagonistic capability were selected for further inhibitory assays against C. beticola. Bacterial strains were identified based on the sequence data of the small subunit-rDNA (SSU-rDNA) gene. Based on the SSU sequence data, the identity of bacterial strains were determined as Bacillus (10 strains: RB1, RB2, RB3, RB4, RB5, RB6, RB7, RB8, RB9, RB10), Paenibacillus (two strains: RP1, RP2), Enterobacter (one strain: RE), and Pseudomonas (one strain: RPs). The results obtained in this study showed that in all of the assays (dual culture, volatile and non-volatile metabolites) bacterial antagonists significantly inhibited the growth of C. beticola compared to the control. Bacillus (RB2) showed the highest inhibition rate on C. beticola in all of the assays. Based on the results of the laboratory assays, three bacterial strains RB2 (Bacillus), RPs (Pseudomonas), and RE (Paenibacillus) were selected for greenhouse assays. The experiment was designed based on a completely randomised design (CRD) with the application of antagonists prior to, simultaneously, and after inoculation with C. beticola on sugarbeet leaves. The reduction in disease severity was evaluated seven days after inoculation. The results of greenhouse assays were consistent with the results of laboratory studies. The obtained results showed that bacterial antagonists significantly reduced the disease severity when compared to the control

Inhibition of Growth and Induction of Apoptosis in Fibrosarcoma Cell Lines by Echinophora platyloba DC: In Vitro Analysis

Echinophora platyloba DC plant (Khousharizeh) is one of the indigenous medicinal plants which is used as a food seasoning and medicine in Iran. The objective of this study was to examine the in vitro cytotoxic activity and the mechanism of cell death of crude methanolic extracts prepared from Echinophora platyloba DC, on mouse fibrosarcoma cell line (WEHI-164). Cytotoxicity and viability of methanolic extract was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and dye exclusion assay. Cell death ELISA was employed to quantify the nucleosome production result from nuclear DNA fragmentation during apoptosis and determine whether the mechanism involves induction of apoptosis or necrosis. The cell death was identified as apoptosis using terminal deoxynucleotidyl transferase- (TdT-) mediated dUTP nick end labeling (TUNEL) assay. Our results demonstrated that the extract decreased cell viability, suppressed cell proliferation, and induced cell death in a time- and dose-dependent manner in WEHI-164 cells (IC50 = 196.673 ± 12.4 μg/mL) when compared with a chemotherapeutic anticancer drug, Toxol. Observation proved that apoptosis was the major mechanism of cell death. So the Echinophora platyloba DC extract was found to time- and dose-dependently inhibit the proliferation of fibrosarcoma cell possibly via an apoptosis-dependent pathway

Inhibitory and Cytotoxic Activities of Salvia Officinalis L. Extract on Human Lymphoma and Leukemia Cells by Induction of Apoptosis

Purpose: Salvia officinalis L., also known as Maryam Goli, is one of the native plants used to Persian medicinal herbs. Hence, the objective of this study was to examine the in vitro cytotoxic activities of a standardized crude methanol extracts prepared from Salvia officinalis L., on a non-Hodgkin’s B-cell lymphoma (Raji) and human leukemic monocyte lymphoma (U937), Human acute myelocytic leukemia (KG-1A) and Human Umbilical Vein Endothelial (HUVEC) cell lines. Methods: The effect of methanolic extract on the inhibition of cell proliferation and cytotoxic activity was evaluated by Dye exclusion and Micro culture tetrazolium test (MTT) cytotoxicity assay. Cell death ELISA was employed to quantify the nucleosome production result from nuclear DNA fragmentation during apoptosis and determined whether the mechanism involves induction of apoptosis or necrosis. Results: The present results demonstrated that methanolic extract at 50 to 800 μg/ml dose and time-dependently suppressed the proliferation of KG-1A, U937 and Raji cells by more than 80% (p800 Ag/ml). Nucleosome productions in KG-1A, Raji and U937 cells were significantly increased respectively upon the treatment of Salvia officinalis L. extract. Conclusion: The Salvia officinalis L. extract was found dose and time-dependently inhibits the proliferation of lymphoma and leukemic cells possibly via an apoptosis-dependent pathway

Induction of apoptosis by grape seed extract (Vitis vinifera) in oral squamous cell carcinoma

Development of novel therapeutic modalities is crucial for the treatment of oral squamous cell carcinoma (OSCC). Recent scientific studies have been focused on herbal medicines as potent anti-cancer drug candidates. This study is the first to investigate the cytotoxic effects and the mechanism of cell death induced by grape seed extract (GSE) in oral squamous cell carcinoma (KB cells). MTT (3-(4,5-dimetylthiazol-2-yl)-2,5 diphenyltetrazolium bromide) and trypan blue assays were performed in KB cells as well as human umbilical vein endothelial cells (HUVEC) were used to analyze the cytotoxic activity of GSE. Furthermore, the apoptosis-inducing action of the extract was determined by TUNEL, DNA fragmentation and cell death analysis. Statistical significance was determined by analysis of variance (ANOVA), followed by Duncan’s test at a significance level of P≤0.05. The results showed apoptotic potential of GSE, confirmed by significant inhibition of cell growth and viability in a dose- and time- dependent manner without inducing damage to non-cancerous cell line HUVEC. The results of this study suggest that this plant contains potential bioactive compound(s) for the treatment of oral squamous cell carcinoma