Homologous recombination of SV4O DNA in COS7 cells occurs with high frequency m a gene dose independent fashion

Abstract

Homologous recombination between microinjected SV4O DNA fragments arid eridogenous SV4O DNA In COS7 cells was analysed by immunofluorescence staIning and DNA blotting Time course experiments revealed that recombination between the transferred (trans) DNA and the chromosomal DNA occurred about 8 hours after microlnjection with hIgh efficiency in a gene dose Independent fashion. Deletions of up to 1018 basepairs (bp) within the early or the tate SV4O region were efficiently repaired after the transfer of linear but not of circular DNA molecules. A 22 bp homology between the trans DNA and the endogenous DNA was sufficient to inttlate recombinatlon but 14 nonhomologous bp at one open end of the SV4O DNA fragments hindered gap repair. © 1988 IRL Press Limited.