Cloning And Functional Analysis On Δ~1-Pyrroline-5-Carboxylate Synthetase Genes GMP5CS1 And GMP5CS2 From Soybean

Soybean is one of the important economic crops in the world, abiotic stress, such as drought, high salt content and low temperature are the important factors influencing the soybean quality and yield. In the process of long-term evolution, plants formed a complex series of defense mechanism against the dangers of abiotic stress. Along with the continuous development of modern molecular biology and genetic engineering technology, the application of plant gene engineering technology developed new crop varieties resistant to inverse has become an important way of modern agricultural production. Mining and utilization of genetic resources of soybean stress response is of great significance.Using molecular biology method, this study received GmP5CS1 and GmP5CS2 gene cloning from soybean varieties Qi Huang 22. Studied the sequence alignment, organization, expression and abiotic stress analysis, then, constructed plant expression vector of the two genes, success converse into Arabidopsis thaliana, analyzed the function of the two genes in resistance to adverse reaction, so aimed at providing genetic resources in order to improve the soybean resistance to reverse and theoretical basis.The main results are as follows:1. The amino acid sequence analysis found that GmP5CS1 contains a length of 2163 bp ORF, encoding 720 amino acids, isoelectric point (PI) is 6.70, protein is weak acid, molecular weight is 78.38 KD; GmP5CS2 contains a length of 2271 bp ORF, encoding 756 amino acids, isoelectric point(PI) is 6.10, acidic protein, molecular weight is 82.18 KD.2. Through the amino acid sequence alignment, found that the two genes of protein sequences contain conservative sites, such as acyl glutamic acid kinase sites and phosphoric acid reductase conservative sites. Phylogenetic analysis showed that GmP5CS1 affinity with Medicago sativa highest, GmP5CS2 affinity with Vigna unguiculata highest. The two proteins have three potential transmembrane helical regions. Subcellular localization predicted that the protein translated by GmP5CS1 may be_located in the chloroplasts, the protein translated by GmP5CS2 may be located in the mitochondria.3. The organization expression analysis found that GmP5CS1 and GmP5CS2 genes have expressed in all soybean organizations. Gene relative expression in leaf and root is higher, relative expression in the stem is middle, the relative expression of flowers and seed is relatively small.4. Abiotic stress analysis shows that the two GmP5CS genes induced the most violent reaction by high salt content stress, cold stress and drought stress is relatively weak.5. Through the method of agrobacterium mediated transformation of arabidopsis, we get the transgenic plants. Under the condition of salt stress, transgenic GmP5CS1 and GmP5CS2 gene into Arabidopsis have stronger resistance to reverse, its root length is longer, higher proline accumulation in the body, compared with wild-type Arabidopsis. These results suggest that GmP5CS2 and GmP5CS1 genes can effectively increase the resistance to high salt stress in transgenic Arabidopsis thaliana, is beneficial to plants grow in the adverse environments.