title: DNA recombination with a heterospecific Cre homolog identified from comparison of the pac-c1 regions of P1-related phages.
abstract: Sequencing of the 7 kb immC region from four P1-related phages identified a novel DNA recombinase that exhibits many Cre-like characteristics, including recombination in mammalian cells, but which has a distinctly different DNA specificity. DNA sequence comparison to the P1 immC region showed that all phages had related DNA terminase, C1 repressor and DNA recombinase genes. Although these genes from phages P7, phi(w39) and p15B were highly similar to those from P1, those of phage D6 showed significant divergence. Moreover, the D6 sequence showed evidence of DNA deletion and substitution in this region relative to the other phages. Characterization of the D6 site-specific DNA recombinase (Dre) showed that it was a tyrosine recombinase closely related to the P1 Cre recombinase, but that it had a distinct DNA specificity for a 32 bp DNA site (rox). Cre and Dre are heterospecific: Cre did not catalyze recombination at rox sites and Dre did not catalyze recombination at lox sites. Like Cre, Dre catalyzed both integrative and excisive recombination and required no other phage-encoded proteins for recombination. Dre-mediated recombination in mammalian cells showed that, like Cre, no host bacterial proteins are required for efficient Dre-mediated site-specific DNA recombination.
authors.affiliation: Stowers Institute, 1000 E 50th Street, Kansas City, MO 64110, USA. BLS@stowers-institute.org
authors.forename: Brian
authors.initials: B
authors.lastname: Sauer
authors.forename: Jeffrey
authors.initials: J
authors.lastname: McDermott
mesh_terms: D000818:Animals; D017101:Bacteriophage P1 / Q000201:enzymology / Q000235:genetics; D001435:Bacteriophages / Q000201:enzymology* / Q000235:genetics*; D001483:Base Sequence; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D042003:DNA Packaging; D004926:Escherichia coli / Q000821:virology; D005814:Genes, Viral; D019426:Integrases / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D011995:Recombination, Genetic; D012097:Repressor Proteins / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D013379:Substrate Specificity; D014764:Viral Proteins / Q000235:genetics* / Q000378:metabolism*; D019065:Virus Assembly
chemical_list: D012097:Repressor Proteins; D014764:Viral Proteins; D004247:DNA; C045073:Cre recombinase; D019426:Integrases