title: The transposition pattern of the Ac element in tobacco cultured cells.
abstract: We investigated physical distances and directions of transposition of the maize transposable element Ac in tobacco cultured cells. We introduced a T-DNA construct that carried a non-autonomous derivative of Ac (designated dAc-I-RS) that included sites for cleavage by restriction endonuclease MluI. Another cleavage site was also introduced into the T-DNA region outside of the dAc-I-RS transposable element. The tobacco cultured cell line BY-2 was transformed with the T-DNA and several transformed lines that had a single copy of the T-DNA at a different chromosomal location were isolated. These lines were co-cultured with Agrobacterium tumefaciens cells that carried a cDNA for the Ac transposase gene under the control of various promoters. Sublines of cultured cells in which dAc-I-RS had been transposed, were isolated. The genomic DNAs of these sublines were isolated and digested with MluI. Sizes of DNA segments generated by digestion were determined by pulse-field gel electrophoresis. Our results showed that 20 to 70% of transposition events had occurred within several hundreds kilo-base pairs (kb) on the same chromosome. These results demonstrate that the Ac-Ds element preferentially transposed to regions near the original site in a tobacco chromosome. In addition, the present results are an example of asymmetric transposition as demonstrated by the distance of transposition on the chromosome.
authors: Division of Biological Science, Graduate School of Science, Nagoya University, Japan.
authors: E
authors: E
authors: Semiarti
authors: H
authors: H
authors: Onouchi
authors: S
authors: S
authors: Torikai
authors: T
authors: T
authors: Ishikawa
authors: Y
authors: Y
authors: Machida
authors: C
authors: C
authors: Machida
mesh_terms: D016960:Agrobacterium tumefaciens / Q000235:genetics; D002461:Cell Line, Transformed; D002478:Cells, Cultured; D018920:Coculture Techniques; D004251:DNA Transposable Elements; D017343:Genes, Plant; D008957:Models, Genetic; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D011995:Recombination, Genetic; D014026:Nicotiana / Q000235:genetics*; D003313:Zea mays / Q000235:genetics
chemical_list: D004251:DNA Transposable Elements