Comparison of generational effect on proteins and metabolites in non-transgenic and transgenic soybean seeds through the insertion of the cp4-EPSPS gene assessed by omics-based platforms.

This work evaluates different generations of transgenic (cp4-EPSPS gene) and non-transgenic soybean plants through proteomics and metabolomics. For proteomics purpose, 24 differentially abundant protein spots were found through 2-D DIGE, being 4 belonging to transgenic plants. From this total, 19 were successfully identified, storage proteins as predominant class. Some identified proteins are involved in growing and cell division, and stress response, such as LEA and dehydrin. For metabolomics, 17 compounds were putatively annotated, mainly belonging to the secondary metabolism, such as flavonoids. From these analyzes, all generations and varieties of the soybean are prone to be differentiate by PLS-DA. According to our results, transgenic plants appear to be more stable than non-transgenic ones. In addition, the omics-based approaches allowed access some relations between those differential spot proteins and metabolites, mainly those storage proteins and flavonoid.

Evaluation of silicon influence on the mitigation of cadmium-stress in the development of Arabidopsis thaliana through total metal content, proteomic and enzymatic approaches.

The mitigation of Cd-stress through Si addition to Arabidopsis thaliana cultivation is evaluated in terms of total metal content, proteomic and enzymatic approaches. Four different treatment are evaluated: TC (control, without Si or Cd addition), T1 (with Si addition), T2 (with Cd addition), and T3 (with Si and Cd addition). Through the total determination of Cd and Si in Arabidopsis leaves, the Cd concentration decreased by half when T2 is compared with T3 treatment. In terms of proteomic approach, some differential protein species are achieved by comparative proteomics through 2-D DIGE of all treatments evaluated. Fifty six differential abundant proteins spots (abundance factor ≥1.5) are detected, and 32 of them accurately characterized and identified through nESI-LC-MS/MS. These proteins are differentially produced due to Cd and/or Si treatments, which mainly include proteins associated with disease/defense, energy and metabolism. The most difference in the abundance of proteins is found due to the presence or absence of Si in plants treated with Cd. Regarding the enzymatic approaches, a major increase is found on APX, CAT and GR activities (5.0, 3.5, and 1.5-fold, respectively). The same is observed for the MDA concentration because an increase of 3-fold is found when TC are compared to those treated with T2. However, when T3 plants are evaluated, the enzymes activities are similar to TC plants. Differences ranging from 6.5 to 21% are detected considering the activity of SOD in the treatments (T1-T3 x TC). The decreased activities of CAT, APX and GR and lower MDA concentration indicate a lower reactive oxygen species production in plants treated with Cd and Si. Based on a proteomics point of view it is possible to conclude that Si-Cd interactions occur at protein level and allow plants to respond effectively to the Cd toxicity, revealing the active involvement of Si on mechanisms involved in Si-induced Cd tolerance in Arabidopsis plants. Additionally, from an enzymatic point of view, it is possible to conclude that Si positively interferes diminishing the negative effects of Cd in Arabidopsis by decreasing the reactive oxygen species generation and increasing the antioxidative enzyme activity.