RRC ID 30116
Author Hong X, Cadwell GW, Kogoma T.
Title Escherichia coli RecG and RecA proteins in R-loop formation.
Journal EMBO J.
Abstract Escherichia coli rnhA mutants devoid of RNase HI exhibit constitutive stable DNA replication, cSDR, which is thought to be initiated from R-loops stabilized in the absence of RNase HI. We found that a combination of an rnhA and a recG mutation is lethal to the cell. recG mutations that inactivate the helicase activity of RecG protein and inhibit reverse branch migration of Holliday junctions impart phenotypes resembling those of rnhA mutants. Thus, recG mutants display cSDR activity, and recG polA double mutants are inviable as are rnhA polA double mutants. These results suggest that the RecG helicase has a role in preventing R-loop formation. A model that R-loops are formed by assimilation of RNA transcripts into the duplex DNA is discussed. The model further postulates that RecA protein catalyzes this assimilation reaction and that RecG protein counteracts RecA in this reaction, resolves R-loops by its helicase activity, or does both.
Volume 14(10)
Pages 2385-92
Published 1995-5-15
PMID 7774596
PMC PMC398347
MeSH Bacterial Proteins / genetics Bacterial Proteins / metabolism* DNA Helicases / genetics DNA Helicases / metabolism* DNA Polymerase I / genetics DNA Repair DNA Replication / genetics* DNA, Bacterial / biosynthesis DNA-Binding Proteins / genetics Escherichia coli / genetics* Escherichia coli Proteins* Genes, Bacterial / genetics Genes, Lethal / genetics Kanamycin Resistance / genetics Models, Genetic Mutation Nucleic Acid Conformation Nucleic Acid Heteroduplexes Rec A Recombinases / metabolism* Recombination, Genetic Replication Origin Ribonuclease H / analysis Ribonuclease H / genetics SOS Response (Genetics) Sequence Analysis, DNA
IF 9.792
Times Cited 67
Prokaryotes E. coli ME9375 ME9580 ME9582 ME9583 ME9586 ME9576 ME9578 ME9569 ME9573 ME9355