RRC ID 30065
Author Ogawa T, Pickett GG, Kogoma T, Kornberg A.
Title RNase H confers specificity in the dnaA-dependent initiation of replication at the unique origin of the Escherichia coli chromosome in vivo and in vitro.
Journal Proc Natl Acad Sci U S A
Abstract Escherichia coli rnh mutants defective in RNase H activity display the features of previously described sdrA (stable DNA replication) and dasF (dnaA suppressor) mutants: (i) sustained DNA replication in the absence of protein synthesis, (ii) lack of requirement for dnaA protein and the origin of replication (oriC), and (iii) sensitivity of growth to a rich medium. Both the sdrA mutants (selected for continued DNA replication in the absence of protein synthesis) and the dasF mutants (selected as dnaA suppressors) are defective in RNase H activity, measured in vitro. Furthermore, a 760-base-pair fragment containing the rnh+ structural gene complements the phenotype of each of the rnh, sdrA, and dasF mutants, indicative of a single gene. One function of RNase H in vivo is in the initiation of a cycle of DNA replication at oriC dependent on dnaA+. In keeping with these results, RNase H contributes to the specificity of dnaA protein-dependent replication initiated at oriC in a partially purified enzyme system.
Volume 81(4)
Pages 1040-4
Published 1984-2-1
DOI 10.1073/pnas.81.4.1040
PMID 6322184
PMC PMC344759
MeSH Bacterial Proteins / genetics* Chloramphenicol / pharmacology Chromosomes, Bacterial / physiology* DNA Replication* Endoribonucleases / metabolism* Escherichia coli / drug effects Escherichia coli / genetics* Genes* Genes, Bacterial* Genetic Complementation Test Genotype Mutation* Phenotype Ribonuclease H Species Specificity Suppression, Genetic
IF 9.412
Times Cited 128
Prokaryotes E. coli ME9177 ME9178 ME9179 ME9136 ME9183 ME9166 ME9167 ME9132