A Preliminary Research on miR156 Regulated Tolerance Mechanism to Cadmium Stress in Arabidopsis Thaliana

Abstract

Recently, soil cadmium pollution is becoming very serious problem in China. Cadmium is a non-essential micronutrient and considered as a most toxic heavy metal. High level of cadmium could cause many adverse effects on plant. miRNAs are kinds of single-stranded non-coding RNAs and related to plant stress response. In this study, we found miR156 play a critical role in the stress tolerance to cadmium in Arabidopsis thaliana. Our results showed that miR156 overexpression plant (156OE) is more tolerant to cadmium stress than wild type plant (WT); whereas miR156 knockout mutant (MIM156) is more sensitive to WT. Several crucial cadmium stress related enzyme activity, biomass and chlorophyll are 156OE>WT>MIM156. Our results demonstrated that miR156 acts as a positive regulator in cadmium stress tolerance of Arabidopsis thaliana. This study laid the foundation for the application of miR156 into soil phytoremediation.