title: Site-specific DNA recombination in mammalian cells by the Cre recombinase of bacteriophage P1.
abstract: The Cre protein encoded by the coliphage P1 is a 38-kDa protein that efficiently promotes both intra- and intermolecular synapsis and recombination of DNA both in Escherichia coli and in vitro. Recombination occurs at a specific site, called lox, and does not require any other protein factors. The Cre protein is shown here also to be able to cause synapsis of DNA and site-specific recombination in a mammalian cell line. A stable mouse cell line was established that expresses the Cre protein under the control of the Cd2+-inducible metallothionein I gene promoter. DNA recombination was monitored with DNA substrates containing two directly repeated lox sites. One such substrate is a circular plasmid with two directly repeated lox sites (lox2) flanking a marker gene and was introduced into cells by Ca3(PO4)2 transformation. As a second substrate we used a pseudorabies virus (a herpesvirus) containing a lox2 insertion designed to provide a sensitive detection system for recombination. In both cases, site-specific recombination in vivo is dependent on the presence of the Cre protein and occurs specifically at the 34-base-pair lox sites. These results demonstrate the controlled site-specific synapsis of DNA and recombination by a prokaryotic protein in mammalian cells and suggest that Cre-mediated site-specific recombination may be a useful tool for understanding and modulating genome rearrangements in eukaryotes.
authors.affiliation: E. I. du Pont de Nemours and Company, Inc., Central Research and Development Department, Wilmington, DE 19898.
authors.forename: B
authors.initials: B
authors.lastname: Sauer
authors.forename: N
authors.initials: N
authors.lastname: Henderson
mesh_terms: D000818:Animals; D001435:Bacteriophages / Q000201:enzymology*; D052688:Bovine papillomavirus 1 / Q000235:genetics; D002460:Cell Line; D004247:DNA / Q000235:genetics*; D004254:DNA Nucleotidyltransferases / Q000235:genetics / Q000378:metabolism*; D004262:DNA Restriction Enzymes; D004251:DNA Transposable Elements; D004274:DNA, Recombinant; D004591:Electrophoresis, Polyacrylamide Gel; D011558:Herpesvirus 1, Suid / Q000235:genetics; D007118:Immunoassay; D019426:Integrases; D051379:Mice; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D011401:Promoter Regions, Genetic; D011995:Recombination, Genetic; D014170:Transformation, Genetic; D014764:Viral Proteins
chemical_list: D004251:DNA Transposable Elements; D004274:DNA, Recombinant; D014764:Viral Proteins; D004247:DNA; C045073:Cre recombinase; D004254:DNA Nucleotidyltransferases; D019426:Integrases; D004262:DNA Restriction Enzymes