Comparative Investigation Of Transferring AtCBF1 Into Rice (Oryza Sativa) And Arabidopsis Thaliana

Low temperature represents a major environmental constrains limiting growth of plants. Low temperature can induce a set of proteins that probably function in protecting cells form stress, and another set of proteous factors that are involved in the further regulation of gene expression and signal transduction in cold stress. CBF1, encodes a transcriptional factor that responds to low temperature and induces the expression of certain cold-regulated genes in Arabidopsis thaliana.In this paper, we transferred gene CBF1 into rice calli and some genetypes of Arabidopsis thaliana by Agrobacteriurn-mediated transformation. The roles of CBF1 transcriptional factor were studied in plants under low temperature, and their possible mechanisms in the development of freezing tolerance were also discussed .We also made some materials for further studying the function of CBF1. The results were as follows:1 CBF1 gene was introduced into rice calli and Arabidopsis by a plant expression vector pCAMBIAlSOl-CSF; containing the CaMV-35S promoter by Agrobacteriurn-mediated transformation . By PCR identification of CBF1, hygromycin selection and GUS assay of transgenic progeny ( rice Tl, Arabidopsis TK T2 and T3 ),two transgenic rice lines and two pure transgenic Arabidopsis lines were obtained . It was demonstrated that foreign genes expressed and stably inherited in transgenic plants.2Freezing tolerance of transgenic plant and wild-type plant were observed under both normal and low temperature by measuring the levels of proline in rice seedlings and suspension cells, and comparision of frozen phenotypic. The results showed that expression of CBF1 elevated the content levels of proline under low temperature, thus enhancing the freezing tolerance in transgenic plants.3Transgenic rice did not display phenotypic alterations (for instance, stunted plants) that observed in transgenic Arabidopsis plants. Line 3 of transgenic Arabidopsis showed a phenotypicalteration- partial albinism.Tail- PCR (thermal asymmetric interlaced PCR) was used to analyzethe locus of T-DNA insertion . In the transgenic Arabidopsis, wedetermined the loci of T-DNA insertions in two lines. In line 1,T-DNA was inserted in F25C20.18 gene on chromosome I, of which thefunction is unknown; in line 3, T-DNA was predicated to insert thechromosome III glycosyl hydrolase family protein 43 gene. So wesuggested that partial albinism maybe resulted from wreck of thisgene.By crossbreed we made a series of mutants with CBF1 gene, andobtained pure lines of Abi4-l-î–ˆFAAbi3-CBF1.1and eskl-CBFL We alsoobtained WS-AEQ transgenic pure line by transformation. AEQ isisolated from the coelenterate jellyfish Aequorea Victoria, hasproven to be a highly sensitive bioluminescent Ca2+ indicator incells.