Proteomics Analysis Of Arabidopsis Seedling In Response To Salt Stress

Soil salinity is a perplexed problem for development of agriculture. As the soil resource is dwindling, how to achieve rational utilization for salinity soil became an important project in the world. Arabidopsis thaliana as a model plant, to study the responding mechanism under the salt stress in Arabidopsis is useful for revealing the salt-resistible mechanism in plant, breeding new varieties with salt-resistant tolerance and achieving rational utilization for salinity soil.Arabidopsis seedling is on research material, the total proteins from the untreated and Na Cl-treated plants were extracted. Separate analyses were carried out on differentially expressed proteins in seedling leaves and seedling roots under 100 m M Na Cl stress by two-dimensional difference gel electrophoresis(2D-DIGE). Using MALDI-TOF/TOF MS mass spectrometry, 127 salt-responsive spots(contain 83 proteins) were identified in seedling leaves, and 109 salt-responsive spots(contain 82 proteins) were identified in seedling roots. Also, these proteins were analyzed by performing COG functional classification, GO annotation, subcellular localization and KEGG pathway analysis. And there are 52 enzymes participate in 22 pathway identified in seedling leaves. Among them,carbon fixation pathway contains 9 identified enzymes, glyoxylate and dicarboxylate pathway contains 5 identified enzymes. And there are 53 enzymes participate in 30 pathway identified in seedling roots. Among them, glycolytic pathway contains 6identified enzymes, glutathione pathway contains 5 identified enzymes. To further evaluate the correlation between the abundances of proteins and their cognate transcripts,62 salt-responsive proteins were selected for RT-PCR to assess expression of the genes that encode these proteins, the results was consistent with protein expression level. To further analysis the function of important salt-responsive genes, we constructed over-expression vectors for 12 genes and obtained transgentic Arabidopsis plants for 10 genes. And we found that the over-expression of CA2 gene could increase the salt-tolerance obviously by performing preliminary salt-tolerance phenotypes verification test about CA2 over-expression lines(T3 generation).Taken together, this study lays a solid foundation for further research on salt-stress response mechanisms in plants.