Proteomic Analysis Of Helianthus Tuberosus Leaves Under Na₂CO₃ Stress

Helianthus tuberosus as a kind of anti-saline-alkaline economic crops, of which is great importance to investigate the physiological response to salt and alkali stresses. Here, H. tuberosus seedlings were exposed to 20 and 50 mmol·L-1 Na2CO3 for 1、3、5 and 7d. The antioxidant enzyme activity in H. tuberosus leaves was measured. Proteomic of H. tuberosus leaves which treated for Na2CO3-7d were analyzed using two-dimensional electrophoresis and mass spectrometry.Oxidative damage was induced in H. tuberosus under Na2CO3 stress. The superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbic acid peroxidase (APX) activity was measured in our research. The results showed that POD and APX is the major antioxidant enzyme to scavenge reactive oxygen species. We assumed that it is an effective way to maintain redox status in H. tuberosus and alleviate damage caused by salt stress on plants.H. tuberosus seedlings were exposed to 20、50 mmol·L-1-7d Na2CO3, of which the leaves soluble proteins were separationed. Based on proteomic analysis,141 Na2CO3-responsive proteins were found but 106 Na2CO3-responsive proteins were identified. Of these, 79 spots differentially expressed (29 spots up-regulated and 50 spots down-regulated) when 20 mmol·L-1-7d Na2CO3 stress treatment group compared with control group.27 spots differentially expressed (8 spots up-regulated and 19 spots down-regulated) when 50 mmol·L-1-7d Na2CO3 stress treatment group compared with control group. Under the Na2CO3 stress, many proteins work together to respond to Na2CO3 stress in the H. tuberosus seedling. The function of differentially expressed proteins was discussed.