What is the function of RFC in eukaryotic replication

RFC, or Replication Factor C, is a eukaryotic protein complex involved in DNA replication. Its primary function is to facilitate the loading of the PCNA (Proliferating Cell Nuclear Antigen) protein onto DNA during the initiation of DNA replication and to help maintain its association with the DNA template during the replication process. Here's a more detailed explanation of RFC's function in eukaryotic replication:

1. PCNA Loading:

   • PCNA is a homotrimeric protein that acts as a sliding clamp, tethering DNA polymerases to the DNA template and increasing their processivity during DNA synthesis.
   • RFC plays a crucial role in loading PCNA onto the DNA template. It recognizes and binds to DNA structures known as primer-template junctions, which are formed during the initiation of DNA replication.
   • Once bound to the primer-template junction, RFC facilitates the opening of the PCNA ring, allowing it to encircle the DNA double helix.

2. DNA Replication Initiation:

   • During the initiation of DNA replication, RFC loads PCNA onto the primer-template junction at the replication fork, where DNA synthesis is about to begin.
   • The loaded PCNA serves as a platform for recruiting DNA polymerases and other replication factors to the replication fork, ensuring efficient and processive DNA synthesis.

3. Processivity Maintenance:

   • Once loaded onto the DNA template, PCNA remains associated with the DNA polymerase as it synthesizes new DNA strands.
   • RFC helps maintain the association of PCNA with the DNA polymerase and prevents its premature dissociation from the DNA template.
   • The stable interaction between PCNA and the DNA polymerase, facilitated by RFC, allows for continuous and uninterrupted DNA synthesis during replication.

Overall, RFC plays a critical role in eukaryotic DNA replication by loading PCNA onto the DNA template and maintaining its association with the DNA polymerase during the replication process. This function ensures efficient and processive DNA synthesis and is essential for the accurate duplication of the genome during cell division.