Chloride Channel Protein CLC-c Is Involved In Growth Regulation And Salt Stress In Arabidopsis And Is Overexpression In Brassica Napus

Plants frequently encountered adverse environmental factors such as salt, drought stress during the growth and development and gradually establish different mechanism including signal transduction, physiological, biochemical and morphological changes to adapt to the environment. In this study, several genes that were induced by salt stress were selected through the analysis of the database and the published literatures for functional characterization in Arabidopsis. The T-DNA insertion mutants of the selected genes were isolated by PCR screening. The, preliminary observation showed that loss transcription of AtCLC encoding Chloride Channel protein conferred plants more sensitive to salt stress, exhibiting shorter root length than wild type plants under salt stress. The root length of clcc mutant plants was only 66% of WT. This suggests that CLC plays a positive role in salt tolerance. To confirm its role in salt stress response, AtCLC-c was overexpressed in Arabidopsis and Brassica napus plants. The results showed that overexpression plants displayed more tolerance to salt treatment with increased seed germination rate and longer root length than WT. OE plants also exhibited enhanced growth. The cell size in OE plants was increased by 50-100%. The result suggests that CLC-c promotes plant growth and salt tolerance. It would be interested to determine its role in Brassica napus. In addition, another gene AtCl28, which is encoding the large submit of ribosomal protein L28, is also involved in salt stress, which will be used for analysis in future study.