Og. Shcherbakova et al., Overexpression of bacterial RecA protein stimulates homologous recombination in somatic mammalian cells, MUT R-DNA R, 459(1), 2000, pp. 65-71
The pairing of homologous molecules and strand exchange is a key event in h
omologous recombination promoted by RecA protein in Escherichia coli. Struc
tural homologs of RecA are widely distributed in eukaryotes including mouse
and man. As has been shown, human HsRad51 protein is not only structural b
ut also functional homolog of RecA. The question arises whether the bacteri
al functional homolog of Rad51 can function in mammalian cells and increase
the frequency of the homologous recombination. To investigate possible eff
ects of bacterial RecA protein on the frequency of homologous recombination
in mammalian cells, the E. coli RecA protein fused with a nuclear location
signal from the large T antigen of simian virus 40 was overexpressed in th
e mouse F9 teratocarcinoma cells. We found that the frequency of gene targe
ting at the hprt locus was 10-fold increased in the mouse cells expressing
the nucleus-targeted RecA protein. Southern blot analysis of individual clo
nes that were generated by targeting recombination revealed predicted type
of alterations in hprt gene. The data indicate that the bacterial nucleus-t
argeted RecA protein can stimulate homologous recombination in mammalian ce
lls. (C) 2000 Elsevier Science B.V. All rights reserved.