Cloning Of CIM Gene From Medicago Truncatula And Genetic Transformation To Medicago Sativa

The CIM(Cytokinin Induced Message)gene belongs to the expansin-B2 gene family.Nowadays the research about CIM gene is mainly on the leaf development of leguminous plants.Medicago truncatula,an annual plant,has the advantages of short growth cycle,small number of chromosomes(2n=16),small genome size,and high genetic transformation efficiency,etc.It is considered to be a model plant for studying leguminous plant genetics.Medicago sativa is one of the most widely grown pasture in the world.Among leguminous pasture species,Medicago sativa has become a high-quality pasture because of its high protein content,rich vitamins and trace elements,and high yield.This study attempts to investigate whether the CIM gene of Medicago truncatula has the ability to affect the compound leaves development of the same genus plant Medicago sativa.In this experiment,the Medicago truncatula R108 species was used as the test material.First,the CIM gene was cloned from Medicago truncatula,the coding region of the gene was 828 bp in length,which encoding 275 amino acids.Then connect the gene to 3302-3flag vector for constructing plant expression vector.The plant expression vector was transfered into Medicago sativa leaves through Agrobacterium-mediated method,and the transgenic Medicago sativa plants were obtained through plant tissue culture technology.Transgenic Medicago sativa plants are obtained by plant tissue culture,then observe its phenotype.The results showed that the compound leaves of transgenic Medicago sativa with CIM gene developed abnormally.Compared with wild-type Medicago sativa,its plants are relatively short with pear-shaped leaves and increased number of branches at the base.Simultaneously,this study further improved the Medicago sativa tissue culture system.