Analysis of Phaseolus vulgaris gene expression related to oxidative stress response under short-term cadmium stress and relationship to cellular H2O2

Abstract

In this study, we aimed to investigate the changes in the malondialdehyde (MDA) content and cellular H2O2 accumulation, which are the oxidative stress markers, and the expression levels of stress-related proteins such as metallothionein (MT) protein, catalase (CAT), Superoxide dismutase (Cu/Zn-SOD), and glutathione S transferase (GST) enzymes. For placing oxidative stress on plants, we used Cd in different concentrations (50,100 and 200 μM) and durations (12,24 and 48 h). The results revealed that MDA content and H2O2 accumulation linearly increase with exposure time and concentration. Although the Cu–Zn/SOD and MT expressions increased at 24 h exposure, they decreased at 48 h exposure. The GST gene is highly expressed at the beginning level of oxidative stress, whereas a decrease in the level of expression was detected with increase in exposure time. Statistical significance was detected in CAT gene expression at 12 h application; however, a decrease in expression level was detected in the 24 and 48 h applications. The results of this study show that transcript accumulation of stress-related genes might coincide with the oxidative levels in the cell and the H2O2 concentration in the signalization structure. Moreover, it could accelerate the expression of the stress genes up to a certain concentration degree, whereas a greater concentration of H2O2 could reduce transcript accumulation.