Gene expression analysis of genes coding key enzymes of cadmium detoxification in garden pea symbiotic nodules

Abstract

Background. Cadmium is one of the most wide-ranging and dangerous pollutants for all living organisms, including plants. Currently, the mechanisms of cadmium accumulation in plant tissues and plant tolerance to its toxic effect are intensively studied. Metal-binding ligands, such as glutathione and phytochelatins, are one of the most important components in cadmium homeostasis in plants. Materials and methods. The pea line SGE and mutant SGECdt differed by cadmium tolerance were used. Gene expression for γ-glutamylcysteine synthetase (GSH1), glutathione synthetase (GSHS), homoglutathione synthetase (hGSHS) and phytochelatin synthase (PsPCS) was measured in pea nodules using realtime PCR. Results. GSH1 expression was slightly influenced by cadmium cloride. GSHS expression was upregulated in SGE and slightly downregulated in SGECdt. Cadmium cloride caused increased expression of hGSHS and PsPCS in both pea line SGE and the mutant SGECdt. Conclusion. Increased tolerance to cadmium of symbiotic nodules in the mutant SGECdt is not linked with expression pattern of analyzed genes.