Genetic Transformation Of Wheat Dehydrin WZY1-2 Gene And Its Spatial-temporal Expression In Different Growth Stages Of Wheat

Drought is an important environmental factor limiting agricultural production.The global arid and semi-arid regions account for about 36%of the total land area and 43%of the arable land.The area of??arid and semi-arid regions in China accounts for about one-half of the country’s total land area,which is mainly distributed in the northwest region.Wheat is one of the major food crops.Drought affects the growth and development of plants,resulting in a 10%-20%reduction in crop production.Therefore,it is of great significance to study the drought resistance mechanism of wheat for increasing grain yield.Dehydrin is one of the proteins accumulated in the late stage of embryonic development and it is a thermostable water-soluble protein.It is induced by cold,high temperature,drought,and salt stress.It may play a molecular chaperone role in the protection of biological metabolism.Stability plays a protective role in lightening the damage caused by drought to plants.The wzy1-2 gene is a new dehydrin member cloned from water-stressed Zheng Yin No.1wheat in our laboratory,but its role in drought resistance remains unclear.The RNA interference technology has high efficiency and specificity.After the target gene is transcribed,it can silence or reject the expression of the target gene,and a loss-of-function mutant is obtained,which has become a powerful tool for studying gene function.Based on the principle of RNA interference and the homology analysis,a 298 bp cDNA sequence between0-298 bp in the dehydrin wzy1-2 gene sequence was selected as the interference fragment,and then cloned interfering fragment was inserted into the efficient plant expression vector pTCK303.Clone sites.Successful construction of RNA interference expression vectors containing inverted repeats.Using immature embryos of Zheng Yin No.1 wheat as explants,2512 immature embryo calli were bombarded by particle bombardment,and 26 regenerated plants were obtained with a regeneration rate of 1.03%.Using the specific primers of the Hpt gene on the expression vector,26 T₀ generation regenerated plants were subjected to PCR analysis.Six Hpt gene positive plants were detected,and the positive conversion rate of Hpt gene was 0.24%.Six transgenic plant seeds were harvested.The number of transgenic plants obtained in this study was small,and the phenotype identification could not be accurately performed.Future investigations and statistics are needed to investigate the role of dehydrin in wheat.To lay the foundation for further study of dehydrin wzy1-2 gene function.In addition,this paper analyzed the expression pattern of drought-resistance of dehydrin WZY1-2 in four different growth stages（during seedling stage,tillering stage,jointing stage,and flowering stage）during the whole growth process of wheat.In the four growth stages,the higher the degree of drought,the higher the expression of wheat WZY1-2 protein in the two wheat varieties,ShaanHe No.6 and Zheng Yin No.1.The expression level of WZY1-2 protein in wheat at the seedling stage was higher than that in the other three growth stages.It was inferred that the nutritional requirement of wheat at the seedling stage was large,and the protein content of the leaves was more.Western blot results showed that the size of the non-specific bands of Shaan He No.6 and Zheng Yin No.1 were different.The wheat WZY1-2 derived from the molecular level is a drought-inducible gene.