Comparative transcriptome profiling of two Brassica napus cultivars under chromium toxicity and its alleviation by reduced glutathione

Abstract

BackgroundChromium (Cr) being multifarious industrial used element, is considered a potential environmental threat. Cr found to be a prospective water and soil pollutant, and thus it is a current area of concern. Oilseed rape (Brassica napus L.) is well known as a major source of edible oil around the globe. Due to its higher growth, larger biomass and capability to uptake toxic materials B. napus is considered a potential candidate plant against unfavorable conditions. To date, no study has been done that described the Cr and GSH mechanism at RNA-Seq level.ResultsBoth digital gene expression (DGE) and transcriptome profile analysis (TPA) approaches had opened new insights to uncover the several number of genes related to Cr stress and GSH alleviating mechanism in two leading cultivars (ZS 758 and Zheda 622) of B. napus plants. Data showed that Cr inhibited KEGG pathways i.e. stilbenoid, diarlyheptanoid and gingerol biosynthesis; limonene and pentose degradation and glutathione metabolism in ZS 758; and ribosome and glucosinolate biosynthesis in Zheda-622. On the other hand, vitamin B6, tryptophan, sulfur, nitrogen and fructose and manose metabolisms were induced in ZS 758, and zeatin biosynthesis, linoleic acid metabolism, arginine and proline metabolism, and alanine, asparate and glutamate metabolism pathways in Zheda 622. Cr increased the TFs that were related to hydralase activity, antioxidant activity, catalytic activity phosphatase and pyrophosphatase activity in ZS 758, and vitamin binding and oxidoreductase activity in Zheda 622. Cr also up-regulated the promising proteins related to intracellular membrane bounded organelles, nitrile hyrdatase activity, cytoskeleton protein binding and stress response. It also uncovered, a novel Cr-responsive protein (CL2535.Contig1_All) that was statistically increased as compared to control and GSH treated plants. Exogenously applied GSH successfully not only recovered the changes in metabolic pathways but also induced cysteine and methionine metabolism in ZS 758 and ubiquinone and other terpenoid-quinone biosynthesis pathways in Zheda 622. Furthermore, GSH increased the level of TFs i.e. the gene expression of antioxidant and catalytic activities, iron ion binding and hydrolase activity as compared with Cr. Moreover, results pointed out a novel GSH responsive protein (CL827.Contig3_All) whose expression was found to be significantly increased when compared than Cr stress. Results further delineated that GSH induced TFs such as glutathione disulphide oxidoreducatse and aminoacyl-tRNA ligase activity, and beta glucosidase activity in ZS 758. Similarly in Zheda 622, GSH induced the TFs for instance DNA binding and protein dimerization activity. GSH also highlighted the proteins that were involved in transportation, photosynthesis process, RNA polymerase activity, and against the metal toxicity. These results indicated that cultivar ZS 758 had better metabolism and showed higher tolerance against Cr toxicity.ConclusionThe responses of ZS 758 and Zheda 622 differed consider...

Reduced Glutathione Mediates Pheno-Ultrastructure, Kinome and Transportome in Chromium-Induced Brassica napus L.

“…Literature has evidenced that a non-enzymatic based antioxidant called GSH play a crucial role in scavenging the ROS, the photosynthesis by-products inside the cell organelles and also inactivates the singlet oxygen species with the help of ascorbate. Thus, GSH helps the plants to get recovery from negative effects of ROS on the plant's growth and development induced by hazardous environmental conditions (Mittler, 2002 ; Gill et al, 2016a ). Moreover, GSH-ascorbate cycle is well-unspoken to detoxify the singlet oxygen species i.e.…”

“…The unique nature of the thiol group helps to stabilize mercaptide–metal bonds. This type of stable bond formation in conjunction with higher water solubility presents GSH as a better scavenger against the toxicity of multiple metals (Gill et al, 2016a ; Zlobin et al, 2017 ), reactive oxygen species (ROS) (Gill et al, 2014 , 2015 , 2016b ), and other hazardous chemicals (Barrameda-Medina et al, 2017 ; Li et al, 2017 ). Previous reports have indicated that GSH plays a vital role in regulating the levels of oxygen singlet species (such as H 2 O 2 ) that can be induced by heavy metal stress in plant cells (Shao et al, 2008 ; Gill et al, 2015 ).…”

“…Oilseed rape as a phytoremediator could serve as the source of a potentially profitable enterprise (Grispen et al, 2006 ). To date, literature studies have clarified that B. napus behaved differently under Cr-induced stress conditions as disclosed by physio-morphic, biochemical, and cell structural attributes (Gill et al, 2014 , 2015 , 2016a ). Furthermore, our recent findings (Gill et al, 2016b ) stated that GSH significantly up-regulated the genomic changes/gene expression that occurred under Cr toxicity in two B. napus cultivars.…”

Complementary RNA-Sequencing Based Transcriptomics and iTRAQ Proteomics Reveal the Mechanism of the Alleviation of Quinclorac Stress by Salicylic Acid in Oryza sativa ssp. japonica

“…RNA was first extracted and mixed with DNase I to avoid DNA contamination Gill et al [ 65 ]. The oligo (dT) magnetic beads were used to enrich mRNA, and cDNA was synthesized by the fragments of mRNA.…”

Bridging a Gap between Cr(VI)-Induced Oxidative Stress and Genotoxicity in Lettuce Organs after a Long-Term Exposure

“…Cr transport promotes gaps in other types of nutrient absorption and water [3]. Most studies on Cr-plant interactions have addressed Cr transfer from soil to plant and Cr hyperaccumulation for phytoremediation purposes (e.g., [4]) and morphophysiological and biochemical responses (e.g., root surface area, growth, morphology, photosynthesis, water/nutrient interactions, and transpiration) (e.g., [1,5]). Cr accumulation promotes an impairment of photosynthesis in the chloroplasts [3]; thus, these effects promoted a reduction of plant biomass [6].…”