title: Mechanism of control of DNA replication and incompatibility in ColE1-type plasmids--a review.
abstract: The related phenomena of ColE1 DNA replication control and plasmid incompatibility are analysed in detail. Replication is negatively regulated in different ways by two gene products, RNA I and gene rop-coded polypeptide, while plasmid incompatibility is specified only by RNA I. Thus, copy-number mutants in the RNA I region usually have altered incompatibility and vice versa. RNA I is transcribed from the opposite strand to RNA II; the processed RNA II transcript serves as the primer for DNA replication. The base-pairing interaction between RNA I and RNA II controls DNA synthesis and incompatibility by preventing primer formation. A model is proposed to explain the phenotype of RNA I mutants in terms of the changes they cause in the secondary structure of RNA I or RNA II.
mesh_terms: D003086:Bacteriocin Plasmids; D004261:DNA Replication; D004269:DNA, Bacterial / Q000096:biosynthesis / Q000235:genetics; D005786:Gene Expression Regulation; D005798:Genes, Bacterial; D008957:Models, Genetic; D009690:Nucleic Acid Conformation; D010957:Plasmids; D012313:RNA / Q000235:genetics*; D012329:RNA, Bacterial / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; C034477:RNA primers; D012329:RNA, Bacterial; D012313:RNA