The Research On Biological Macromolecules Protection About ASR Protein Of Soybean And Its Conservative Structure Domain Of Short Peptide A1 ~ A5

ASR proteins are the seventh group of LEA proteins and it’s also a suite of important family proteins found in organisms, which are generally involved in osmoregulation. They will be induced in plants under stress conditions, such as drought, low temperature, salt stress and ABA. The overexpression of ASR proteins can reduce plant injure by stress. It is of great significance to understand the molecular mechanism of ASR protein reactions in plant stress tolerance by research on stress-resistance protection and determine the functional domain in stress tolerance of ASR proteins.Gm ASR protein are one of the ASR protein family which is composed of 238 amino acids, with five conservative domain structure. In this article, we designed and synthesized Gm ASR short peptide series A1 ~ A5. Under Freeze-thaw stress conditions, Gm ASR protein and its short peptide series A1 ~ A5 are able to prevent LDH enzyme inactivating and aggregating. To verified Gm ASR protein and the short peptide series A1 ~ A5 has anti Htt Q53(Huntington’s disease related proteins) aggregation through the Filter Trap experiments.Visible, Gm ASR protein and its short peptide series for protein protection is showed no specificity of choice.This is one way Gm ASR protein protection plant cell.Gm ASR protein contains a high proportion of histidine, up to 9.8%, and each domain are rich in Histidine. Histidine is an amino acids in combination with metal ions, However,whether the histidine in conservative structure domain can combine with metal ions or not,and how to affect its antioxidant ability still remains to be seen. In this paper, through the solid metal chelate affinity chromatography experiment proved Gm ASR protein and its short peptide series A1 ~ A5 can be combined with Cu2+ and Cd2+. We use Cu-ascorbate system method to detect Gm ASR protein and its short peptide series A1 ~ A5 has the ability to remove hydroxyl radicals, and Gm ASR short peptide series A1 ~ A5 experimental results found a positive correlation between the hydroxyl free radical removal ability and the number of histidine, also the length of the short peptide amino acid sequence. At the same time,Gm ASR and the short peptide protein series A1 ~ A5 also can protect DNA from oxidative damage by hydroxyl radicals.In addition, this paper proves that Gm ASR protein will also occur reversible accumulation of precipitation after combined with Cu2+, speculated that this may be one of the important ways of Gm ASR protein reduce ion to poison plant cells. This also suggests Gm ASR protein also can be used as a metal ion-buffer agent in the cell, stabilized imbalance that caused by stress of Cu2+ ions in the cell, this is also the one way Gm ASR protein to protect plant cell.