A Preliminary Study On The Function Of Arabidopsis Thaliana Seed Storage Protein AtSSA3

Seed Storage Protein(SSP)is the most abundant protein in mature seeds,which not only affects the quality of seeds,but is also a source of energy for seed germination and seedling growth.The previous research of our research group found that the deletion mutants related to the nitrogen metabolism pathway can significantly improve the tolerance of plants to salt stress.The transcriptome sequencing technology further analyzes the deletion mutants of the nitrogen metabolism pathway under salt treatment and shows that the seed storage protein gene AtSSA3 can respond to salt stress and significantly down-regulate its expression under salt treatment.Therefore,further exploration of the function of AtSSA3 gene in the process of plant response to salt stress provides a theoretical basis for a better in-depth study of the relationship between nitrogen metabolism and plant salt tolerance.1.Analyze the expression characteristics of the seed storage protein gene AtSSA3 by real-time quantitative PCR.The results show that the gene is expressed to varying degrees throughout the growth and development cycle of the plant,and the expression is the largest in dry seeds.There is a significant response relationship with NaCl,NH4Cl,Urea,ABA and GA3.AtSSA3 gene expression is significantly down-regulated by NaCl,NH4Cl and ABA;AtSSA3 gene expression is significantly up-regulated under Urea treatment;AtSSA3 gene expression is significantly increased with treatment time under GA3 treatment The increase first increases and then decreases.2.The AtSSA3 gene deletion mutant(atssa3)material was analyzed under salt treatment.The results showed that the seed germination rate of atssa3 under salt treatment was significantly higher than that of wild type(WT),and the growth and root length of atssa3 were also better than that of WT.The NH4+ content is lower than WT,that is,the deletion of AtSSA3 gene can reduce the NH4+ content in plants under salt stress,thereby significantly improving the tolerance of plants to salt stress.3.The yeast two-hybrid technique was used to further screen the protein that interacts with the seed storage protein AtSSA3.As a result,a total of 12 positive strains were obtained.After the yeast co-transformation verification,the interaction between AtARA4 and AtSSA3 was confirmed.The optimal conditions for the expression of AtARA4 and AtSSA3 were obtained by protein induction,and the in vitro Pull-down experiment further verified the interaction between AtARA4 and AtSSA3.In summary,this study conducted a preliminary study on the function of the seed storage protein AtSSA3,laying a foundation for in-depth exploration of the function of this gene in the process of plant response to salt stress.