| Soil salinization is one of the most important abiotic factors which limited the production of a large number of crops worldwide. As the salinization of the soil, majority of the crops were unproductive. How to improve the salt-tolerance of plants and enhance the availability of salinized land is an urgent scientific problem which needed to be sloved. However, to Improve the salt-tolerance of plants is an important biological approach. Traditional studies focused on measuring and analyzing the physiological and biochemical parameters of the plants in salinized condition, as well as control their gene transformation and expression. These have difficulties in revealing the comprehensive mechanism of how plants are tolerant to high concentration of salt. Protein is the executor of the life, also it is the performer of the life. Therefore, to specify the structure and the function of the protein by means of proteomics is a direct method which can elucidate the mechanism of salt-tolerance of plants.In this study, we use wild Arabidopsis, a model organism, as experimental material. In doing so, we first classify the gemmiparous seeds (length of roots to approximately1.5cm-2cm) into two classes, one of the group immersed in120mmol/LNaCl solution for eight days, on the contrary, the control group cultivated in solution without salt. On the next step, we specificly record the characteristics of both morphology, physiology and biochemistry of wild Arabidopsis. Finally, we make a comparison between the control group and treated group according to three of the above parameters, and we can obtain the following conclusions.(1) Arabidopsis, treated by120mmol/L NaCl solution, have a significantly slow growth, with smaller leaves and growth restricted roots. Eight day later, part of the Arabidopsis leaves turned to be yellow.(2) By analyzing the physiological and biochemical value of the Arabidopsis leaves, we found that there were significant increases of the proline, Malondialdehyde (MDA) and soluble sugar content of the treated group compared with the control group, these implied that the damages to the Arabidopsis could be accelerated with the immersed time in120mmol/L NaCl solution. What is more, the plants tolerance could be improved through synthesis plant proline, soluble sugar etc osmotic regulation substances in order to improve the ability of water resistance mechanism, in response to stress and improve the resistance to salt.(3) Arabidopsis roots PME activity was measured and analyzed, and salt stress early and treated root PME activity was significantly higher, with the accumulation of salt stress time, the PME activity in the treatment group have been slowed down, but still have higher PME activity. This indicates that the PME activity increased rapidly in the early period of salt force in responsing salt damage. When the plants adapted the environment, the PME activity will be slowly reduced, but in general, in every different stages, PME activity of the treated group is still slightly higher than the control group.(4) Two groups of Arabidopsis material treated by TCA/acetone extraction of proteins by SDS-PAGE electrophoresis patterns showed that there are significantly differences of the protein expression between the treated group and the control group, specificly, the performance of the treated group has a higher25KDa and30KDa protein while lower with20KDa protein. After Two-dimensional electrophoresis, the glue figure of these two groups of proteins analysis by ImageMaster2D Platinum5.0software. Data shows that these two-dimensional polyacrylamide gel electrophoresis had a close correlation (r=0.929).So we selected20significant changes in protein spots,10spots were up-regulated,10down.And more,we statistic theoretical isoelectric point and molecular weight preliminarily of20protein spots(including the newly induced two proteins),which significantly changes under stress conditions. |
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