| MAPKKs (mitogen-activated protein kinase kinases) are the key components in the signal transduction passways which regulate a variety of cellular processes in eukaryotes including in plants. In the present study, an omanental flower Sinningia speciosa was transformed with tMEK2 and tMEK2MUT:, the wild type and mutant type of MAPKK from tomato, by Agrobacterium tumefaciens. The aim of this research is to establish a transgenic system for flower plants and investigate the functions of MAPKK in transgenic plants in the future.The expression vectors of tMEK2 and tMEK2MUT: were constructed and transformed to Agrobacterium tumefaciens through freezing-melting method. The tMEK2 and tMEK2MUT was amplified by PCR and then cloned to pMD 18 -T vector. To express the genes in plants, the coding region of tMEK2 and tMEK2MUT were placed between the 35S promoter and NOS terminator of pIBl, respectively. Finally the expression cassette of the two genes were inserted into binary vector pBin19. And the expressin vector pBM has a selection gene NPT II.A genetic transformation system was established by using leaf discs of Sinningia speciosa. The results show that kanamycin significantly suppressed the regeneration of buds and roots, and the suitable concentrations for selection of transformants are 50 mg/L and 10 mg/L, respectively. Cefotaxime inhibited the bud regeneration at concentrations more than 250 mg/L , so the concentration used in suppression of Agrobacterium is 200 mg/L. To gain the maximum transformation efficiency, the explants should be pre-cultured two days, co-cultured four days and infected with Agrobacterium tumefaciens for ten minutes. Aacetosyringone, at a cpncenration of 100 μmol/L, also improves transformation efficiency.PCR was used to detect transgenic plants in the regenerated shoots. The results show that NPT II had already integrated into the genome of Sinningia speciosa, and the transformation efficiencies of tMEK2 and tMEK2MUT were 1.7% and 0.7%, respectively.
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