Genetic Transformation Of Arabidopsis By Agrobacterium Tumefaciens Carring Cucumber GST Genes And The Enhancement Of Anti-high Temperature Capability In Transgenic Plants

Glutathion S-Transferases have been found in all plans species.Most GST distrbuted in all of plant tissues as soluble dimeric enzymes.The divierse electrophilic centres on lipophilic molecules can conjugation of the thiol group of the giutathione(GSH) and catalyse it to high water soluble and less toxic products.In this paper,the gene expression and GST activity under high-temperature stress of cucumber were analyzed. Glutathion S-Transferases(GST)gene was cloned,the GST plasmid was constructed and transgenic Arabidopsis overexpressing this genes were acquired.Under high-temperature stress,the gene expression,maximum PSII quantum yield,enemyzes activity were analyzed in the transgenic plants.The main results are as follows:1,The conclusion had got from qRT-PCR that GST gene had been markedly up-regulated when cucumbers were treating in high-temperature. Analysis of the activity of enzymes in stress showed that the activity of GST rose strongly.2,The 648kb coding region of GST gene was amplified from cucumber through PCR.We obtaind the new expression vector 1300-GST by degesting and ligating.Then transferred it into E.coli competent cell-DH5αby liquid nitrogen freeze thaw method.3,Transferred the new vector into Agrobacterium tumefaciens strain EHA105.4,Expression plasmid were transferred into Arabidopsis via Agrobacterium-mediated transformation.PCR analysis showed that hygromycin-resistant transgenic Arabidopsis were obtained.5,After under 72d 40℃high-temperature stress, qRT-PCR detection showed that the expression of GST in plants was different.Farther detection showed that the maximum PSII quantum yield in transgenic type is more than wild type.