title: Genetic evidence that control of F replication is negative.
abstract: We have taken advantage of two situations in which the incompatibility barrier between F plasmids is overcome to show that wild-type genes controlling F copy number (cop+) are dominant in trans over mutant genes. The simplest interpretation of our findings is that the cop mutations have inactivated a repressor gene that controls F replication. Since the cop. mutations all map in a region that others have shown by sequence analysis to theoretically encode four proteins, a strong possibility exists that one of these proteins is the repressor.
mesh_terms: D004261:DNA Replication; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D005786:Gene Expression Regulation; D005809:Genes, Regulator; D005816:Genetic Complementation Test; D009154:Mutation; D010957:Plasmids; D011995:Recombination, Genetic; D012093:Replicon
chemical_list: D004251:DNA Transposable Elements; D004269:DNA, Bacterial