Replication factor C

The replication factor C, or RFC, is a five-subunit protein complex that is required for DNA replication.

The subunits of this heteropentamer are named Rfc1, Rfc2, Rfc3, Rfc4, and Rfc5 (in S. cerevisiae). RFC is used in eukaryotic replication as a clamp loader, similar to the γ Complex in E. coli. Its role as clamp loader involves catalysing the loading of PCNA on to DNA. It binds to the 3' end of the DNA and uses ATP hydrolysis to open the ring of PCNA so that it can encircle the DNA.