The Effect Of Cold Stress On Subcellular Localization Of Wheat Dehydrin WZY2

The inability of plants to flee an environmental stress has resulted in the evolution of an extensive stress response system.One example of an abiotic stress is dehydration,which can take the form of drought,high salinity,or freezing.During periods of dehydration,a wide variety of plants can express dehydrins,which are involved in protecting the plant from the negative effects of dehydration.The studies have shown that wzy2 promoter contains several potential stress-related cis-acting regulatory elements,including LTREs.Although transcript of gene wzy2 was accumulated and wzy2 promoter activity was upregulated under cold stress,the molecular function of WZY2 protein is still unclear.Through the result of WZY2 protein's subcellular localization in different cold stress-sensitive wheat,we could analyze response mechanism of WZY2 in different wheat leaves and make foundation of function research of WZY2.The transient expression system of Wheat leaves is commonly used in the interaction between wheat and powdery mildew.In order to adjust the system to our research,we optimized some parameters in disinfection ways of leaves and the amount of gold powder.The method of fusion report gene localization was applied in our study,we constructed the fusion expression vector "pTF486-wzy2" by using PCR amplification,enzyme digestion and connection technology and transformed it into leaves of wheat "Chinese spring" and"Zhengyin 1#" by gene gun transduction.After 3 days of low temperature treatment at 4?and 2 days of normal temperature at 25 ? to wheat leaves,we observed the fusion protein WZY2-GFP in the fluorescence microscope.The result of transient expression showed that dehydrins WZY2 positioned in the nucleus and cytoplasm of leaf epidermal cells in the normal state.It is noteworthy that aggregation of WZY2 occurs in the binding between epidermal cell and lower part cell which is water loss point,showing irregular distribution of punctate in the fluorescence microscopy.GFP also exhibited the same distribution as WZY2-GFP in cells.After cold treatment,WZY2 protein dispersed into the cytoplasm from water loss point,whereas GFP was stranded in rallying point.The results indicated that low temperature affects the localization of WZY2.Moreover,We found that the WZY2 in wheat "Chinese spring"leaves made reaction to the low-temperature treatment in 1-2 days,while the behavior in wheat 'Zhengyin 1#" took 2-3 days.Under low temperature treatment,WZY2 migration occurs in two different types of wheat seed at different rates,suggesting that is related to the sensitivity of wheat types to low temperature.