Mechanism of Discontinuous Dna Replication in Escherichia Coli

Replication of DNA is fundamental to all actively growing cells. In Escherichia coli, DNA replication is initiated at specific site on the genomic DNA, termed oriC, and then proceeds bidirectionally to the terminus. The question whether discontinuous DNA replication operates only for the lagging strand or for both strands in E. coli remains an issue of controversy in the literature, although data from most in vivo studies are clearly in favor of a discontinuous DNA replication model. For discontinuous DNA synthesis to operate on both DNA strand, one would predict that RNA primers are synthesized on both leading and lagging strands. In this application, we propose: (i) to determine if the leading-strand Okazaki DNA fragments contain RNA at their 5』end, and (ii) to identify and characterize the genes (or factors) that are involved in the assembly and/or progression of leading-strand primosome complex. It is anticipated that the results obtained from this proposal will resolve the lingering question whether discontinuous DNA replication operates only for the lagging strand or for both strands in vivo.

Project ID:PA9706-0223
External Project ID:NSC95-2311-B182-008-MY3