[Agents that act on chromatin structure affect the rate of intrachromosomal homologous DNA recombination in cultured cells].

A study was made of the influence of sodium butyrate and luminol on the rate of homologous recombination of aminoglycosidephosphotransferase gene copies, which contain non-overlapping deletions and are integrated in chromosomes of the Chinese hamster cells of line A238. It is shown that treatment of cells of transformed clones with sodium butirate, which is known to stimulate DNA reparation and to loosen chromatin structure, inhibits intrachromosomal homologous recombination. Dexametazone, which is also capable of stimulating DNA reparation, displayed similar effect. In contrast, the treatment of cells with luminol, inhibiting DNA reparation and condensing chromatin structure, increased the efficiency of intrachromosomal homologous DNA recombination.