Open AccessCircular and linear simian virus 40 DNAs differ in recombination.
Author(s) -
Dale Dorsett,
Ida Deichaite,
Ernest Winocour
Publication year - 1985
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.5.4.869
Subject(s) - in vitro recombination , biology , recombination , dna , site specific recombination , recombinant dna , dna supercoil , homologous recombination , microbiology and biotechnology , dna replication , tandem repeat , replication protein a , rolling circle replication , circular bacterial chromosome , dna polymerase ii , flp frt recombination , genetic recombination , genetics , recombinase , genome , gene , molecular cloning , dna binding protein , polymerase chain reaction , reverse transcriptase , complementary dna , transcription factor
Linear forms of simian virus 40 (SV40) DNA, when added to transfection mixtures containing circular SV40 and phi X174 RFI DNAs, enhanced the frequency of SV40/phi X174 recombination, as measured by infectious center in situ plaque hybridization in monkey BSC-1 cells. The sequences required for the enhancement of recombination by linear DNA reside within the SV40 replication origin/regulatory region (nucleotides 5,171 to 5,243/0 to 128). Linearization of phi X174 RFI DNA did not increase the recombination frequency. The SV40/phi X174 recombinant structures arising from transfections supplemented with linear forms of origin-containing SV40 DNA contained phi X174 DNA sequences interspersed within tandem head-to-tail repeats derived from the recombination-enhancing linear DNA. Evidence is presented that the tandem repeats are not formed by homologous recombination and that linear forms of SV40 DNA must compete with circular SV40 DNA for the available T antigen to enhance recombination. We propose that the enhancement of recombination by linear SV40 DNA results from the entry of that DNA into a rolling circle type of replication pathway which generates highly recombinogenic intermediates.