Some Characteristics of Transgenic Clones of Mouse R1 Line Embryonic Stem Cells.

Transgenic clones of mouse embryonic stem cells of the RI line were -received by transfection of plasmid linear vectors. The changes in the transgene structure during its integration into the genome of the target cells were investigated. Displacements were found on the flanks of the integrated transgene. It was found that multicopy tandem structures are formed in head- -tail orientation at the transgene integration. It was noted that the number of copies of the integrated transgenes varies considerably, but the introduction of DNA fragments from the nuclear shells into the flanks of the transgene normalizes the number of its copies.