Construction Of Plant Expression Vectors Carrying 2-5A And RNase L Gene And Transformation To Tobacco And Wheat

In mammals,the interferon system provides such a universal antiviral mechanism,proteins secreted by virus-infected animal cells during cell proliferation and in several immunological processes they induces the synthesis of additional proteins that directly lead to the inhibition of virus multiplication.One of these proteins is the 2,5-oligoadenylate synthetase which is activated by double-stranded RNA(dsRNA). Once activated,the enzyme polymerizes ATP to a series of 2,5-oligoadenylates(2-5A),and then 2-5A activates a latent endoribonuclease(RNase L) which degrades viral RNA.In this study, with the help of the intermidiate vector pJIT163,2-5A gene and Rnase L gene were cloned into the binary plant expression vector pBINplus to obtain the plant transformation/expression vector pBIN2-5A and pBINRL.These vectors were used for Agrobacterium-mediated transformation of tobacco cultivar Yunyan-87 .The resultant transgenic plants transformated with 2-5A gene and RNaseL gene,respectively and inclusively were confirmed by PCR ,and their resistance to virus was measured by inoculation of TMV-B and ReMV respectively.The resistance to virus is still under investigation.Co-transformed with plant expression vector p2-5A-RNase L carrying 2-5A gene and Rnase L gene and the expression vector pAHC carrying a herbicide-tolerance gene by means of the gene-gun method, 167 positive transformants ( TO) was acquired from about 5000 wheat embyos of cultivar"Yumai-18".After herbicide-selection,PCR-screening,4 transgenic plants (T1) carrying the target genes were obtained.