Abstract:
To elucidate the mechanism of tolerant of exposed
Perilla frutescens (L.) Britt. to cadmium stress, a set of hydroponic culture experiments were set up to analyze the differential expressions of proteins in
P. frutescens leaves after 3 weeks of exposure. The study used two-dimensional electrophoresis technique and added Cd
2+ to hydroponic solutions of the hydroponic culture experiments. Based on the results, 25 proteins changed in
P. frutescens leaves and 20 of them were identified by LC-MS/MS analysis. The identified proteins included 3 proteins related to photosynthesis, 11 proteins related to energy metabolism, 1 protein related to stress, 2 proteins related to protein metabolism, 1 protein related to gene expression, 1 structural protein, and 1 protein related to biosynthesis and detoxication. Under Cd
2+ concentrations of 2.0 mg·kg
-1, 5.0 mg·kg
-1 and 10.0 mg·kg
-1, ATP synthase, serine carboxypeptidases and plant cytochrome P450 up-regulated in
P. frutescens leaves, but oxygenase large subunit, ribosomal protein S3 and actin down-regulated in
P. frutescens leaves. Furthermore, photosystem Ⅱ stability/assembly factor HCF136 and acyl-CoA thioesterase up-regulated in low Cd
2+ concentration of 2 mg·kg
-1, but down-regulated in higher Cd
2+ concentrations of 5 mg·kg
-1 and 10 mg·kg
-1. Phosphoribulokinase/uridine kinase family protein up-regulated under 2 mg·kg
-1 and 5 mg·kg
-1 Cd
2+ concentrations, but no difference was detected under 10 mg·kg
-1 Cd
2+ concentration. Additionally, retrotransposon protein involved in gene expression down-regulated under 10 mg·kg
-1 Cd
2+ concentration. The results indicated that
P. frutescens strengthened energy metabolism, reduced photosynthesis, altered protein metabolism and gene expression, and improved detoxification under Cd
2+ stress, and thereby enhanced
P. frutescens cadmium tolerance.