Replication of singly primed ssM13 DNA by hPolɛ. (A) Replication in the presence of human and S. pombe RFC and PCNA. Reaction mixtures (10 μl) containing hPCNA or spPCNA, hPCNA or spRFC, and hPolɛ were incubated for 45 min at 37°C as described in Materials and Methods. The levels of PCNA added were 50 ng (lanes 1, 3, 5, 7, and 10) and 10 ng (lanes 2, 4, 6, and 8). All reactions contained 150 mM sodium glutamate. (B) Effect of spPCNAs on the spRFC-dependent replication of M13 DNA by hPolɛ. Reaction mixtures (10 μl), containing the indicated levels of spPCNAs, 0.1 unit of spRFC, 0.18 unit of hPolɛ, and 0.15 M sodium glutamate, were incubated at 37°C for 45 min. wt, wild type.