Replication factors required for SV40 DNA replication in vitro. II. Switching of DNA polymerase alpha and delta during initiation of leading and lagging strand synthesis
Year: 1991
Type: article
Abstract: Replication factors A and C (RF-A and RF-C) and the proliferating cell nuclear antigen (PCNA) differentially augment the activities of DNA polymerases alpha and delta. The mechanism of stimulation by these replication factors was investigated using a limiting concentration of primed, single-stranded template DNA. RF-A stimulated polymerase alpha activity in a concentration-dependent manner, but also suppressed nonspecific initiation of DNA synthesis by both polymerases alpha and delta. The primer recognition complex, RF-C.PCNA.ATP, stimulated pol delta activity in cooperation with RF-A, but also functioned to prevent abnormal initiation of DNA synthesis by polymerase alpha. Reconstitution of DNA replication with purified factors and a plasmid containing the SV40 origin sequences directly demonstrated DNA polymerase alpha dependent synthesis of lagging strands and DNA polymerase delta/PCNA/RF-C dependent synthesis of leading strands. RF-A and the primer recognition complex both affected the relative levels of leading and lagging strands. These results, in addition to results in an accompanying paper (Tsurimoto, T., and Stillman, B. (1991) J. Biol. Chem. 266, 1950-1960), suggest that an exchange of DNA polymerase complexes occurs during initiation of bidirectional DNA replication at the SV40 origin.
Source: Journal of Biological Chemistry
Authors: T Tsurimoto, B Stillman
Institution: Cold Spring Harbor Laboratory
Language: English
Topic: DNA Repair Mechanisms
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,430
Funder: National Cancer Institute
OpenAlex ID: W1625430625