Optimization Of Soybean Embryonic Tip Genetic Transformation System And Identification Of MYB Transcription Factor Transgenic Soybeans

As an important crop in China，Soybean (Glycine Max (l.) Merr) provides not onlylarge cooking oil and protein, but also a variety of biological activity such as isoflavone.Soybean isoflavone is a kind of secondary metabolites and plays an important role inhuman health. MYB （v-myb avian myeloblastosis viral oncogene homolog）factor is themost common type of functional transcription factor, it is involved in the regulation ofsoybean isoflavones synthesis pathway. So in order to improve soybean isoflavones content,The efficient system of soybean genetic transformation was build on the basis of transgenictechnology.Due to the low efficiency on trangene technique of soybean, how to improve thegenetic transformation efficiency of soybean has been one of the urgent problems and needto be solved. In this study, soybean variety jilin No.35is mainly pointed as the receptors,the optimization of agrobacterium mediated genetic transformation system of soybeanembryonic tip about the key factors such as may affect the conversion efficiency. Duringgermination stage and co-culture to add the concentration of hormone, hormone activationmethod, choice of hormone type and concentration at rooting stage. Results shows that thesoybean germ pointed in the genetic transformation system of suspension are AS adding100umol/L, weight of OD6000.6-0.8suspended bacterium liquid ice bath for1h, add1.1mg/L IAA rooting stage. Using the optimized system, this paper average conversion ratereached25.30%, and after25d the transplant with resistance can be get. It was significantlyenhanced comparison to the conversion system before. And to a certain extent, the trainingcycle is shortened. It is demonstrated that the optimization system of genetic transformationfor jilin No.35embryo are feasible.The resistance of plants was tested. The main detection methods are: marker genedetection by PCR, gene protein bar strip detection, Daubing resistant plants by Glufosinatedaub, protein detection by Western blot. Five different varieties of T0generation plant wasget, the conversion rate of five varieties respectively.The T1generation of transgenic plantswas taken, the positive rate is17.82%.22positive transformation strain was developed on T1generation,16positive transformation strain was developed on T2generation,and somevarieties of positive T3were get.The high performance liquid chromatography (HPLC) method was used to investigatetest T3transgenic plants the content of soybean isoflavone. The isoflavone content werechanged of MYB12B2, MYB12A transcription factor in seeds and by leaves of soybean.Results show that MYB transcription factors of soybean isoflavones content has improved,MYB12B2of isoflavones metabolic regulation was more apparent.The most increasing ratesis that jilin35increased2.89mg/g.