Replication factor C (RFC).


Loads PCNA on primed templates (1) and is involved in the switch between DNA polymerase a and polymerases d and e.




Molecular weight

•Five subunits, Rfc1-5 sizes 140,86, 41,40,37

Biochemical properties

•DNA binding, binds primed DNA covered in ssb 3’OH terminus

•50x preference for primer template over ds/ss DNA (2)

•ATPase. ATP hydrolysis coupled to closing of PCNA ring around DNA

•Stops pol alpha (3)



•AAA+ motif; ATP binding site (Rfc1-5)

•LXCXE (Rfc1) (4)

•Arg fingers (5)

•BRCT domain (ScRfc1) (6)


Protein interactions

•PCNA (stimulates ATPase) (7) (8)



•Asf1 (9)

•Rpa (10)

•Ctf4 /18 (11)

•Ctf7 (12) athough more recent speculation that this is through pcna and not direct with RFC (13)

• telomeres (14)



SpCdc24 (15)



•DNA ligase 1 (16) mammals


Rfc1 only



• SMC1 (17) yeast



•Primase (18) human

• Brd4 (chromatin binding protein 2 bromodomains) (19) human

•Rb/ccat enhancer binding protein/hdac1 (20) human



•Rfc1 phosphorylation by CK2 (21) stops PCNA binding, cell cycle dependent max in G2/M (22) Phosphorylation Rfc1 causes it to dissociate from small (non- phosphorylated) subunits. CK2  also phosphorylates PCNA binding site in adipocyte differentiation. (23)



X-ray (24)

Em structure with pcna (25) (26)

Cellular location and expression


Other Comments

•Subcomplex 36,37,40 more stable has ATPase and primed DNA template binding. Can unload PCNA from templates but can’t bind it on (27)

•Involved in sister chromatid cohesion (28)

•Interacts with  telomeric DNA (14)

•Suggested homology to Cdc6 in 8 regions (29) Orc1 (30)

•Involved in DNA repair (31)


Alternative RFC complexes exist in which large subunit is replaced.


•ScRad24/SpRad17-Rfc2-5 is involved in DNA damage and replication checkpoint pathway. Loads 911 complex (Sc Rad17-Mec3-Ddc1; Sp Rad9-Hus1-Rad1) onto DNA damaged sites in manner analogous to RFC loading of PCNA. (32) (33)


•ScCtf18/ScChl12-Rfc2-5-Dcc1-Ctf8 is involved in establishing sister chromatin cohesion during S phase (34) (11) (35)

 This complex has been reported to catalyse PCNA loading and unloading while main RFC complex only does loading (36) . In co-operation PCNA ctf18 stimulates pol nu activity (37)

• proposed role in telomere replication (38)


•Elg1-Rfc2-5 – function unclear (34) }



• Checkpoint involvement (rfc3) (39)



• Checkpoint involvement rfc4 (40)



• Frag1 conserved homologue rfc human involved in linking cell stress and apoptosis (41)

• multiple splice forms

• Cleaved in apoptosis (42) by caspase (43)



•2 rfc like subunits (44)


Last edited

13 April 08





1.    Podust,V.N., Tiwari,N., Stephan,S. and Fanning,E. (1998) Replication factor C disengages from proliferating cell nuclear antigen (PCNA) upon sliding clamp formation, and PCNA itself tethers DNA polymerase delta to DNA. J Biol Chem 273, 31992-31999.

2.    Hingorani,M.M. and Coman,M.M. (2002) On the specificity of interaction between the Saccharomyces cerevisiae clamp loader replication factor C and primed DNA templates during DNA replication. J Biol Chem 277, 47213-47224.

3.    Mossi,R., Keller,R.C., Ferrari,E. and Hubscher,U. (2000) DNA polymerase switching: II. Replication factor C abrogates primer synthesis by DNA polymerase alpha at a critical length. J Mol Biol 295, 803-814.

4.    Pennaneach,V., Salles-Passador,I., Munshi,A., Brickner,H., Regazzoni,K., Dick,F., Dyson,N., Chen,T.T., Wang,J.Y., Fotedar,R. and Fotedar,A. (2001) The large subunit of replication factor C promotes cell survival after DNA damage in an LxCxE motif- and Rb-dependent manner. Mol Cell 7, 715-727.

5.    Johnson,A., Yao,N.Y., Bowman,G.D., Kuriyan,J. and O'Donnell,M. (2006) The replication factor C clamp loader requires arginine finger sensors to drive DNA binding and proliferating cell nuclear antigen loading. J Biol Chem281, 35531-35543.

6.    Miyake,T., Hu,Y.F., Yu,D.S. and Li,R. (2000) A functional comparison of BRCA1 C-terminal domains in transcription activation and chromatin remodeling. J Biol Chem 275, 40169-40173.

7.    Podust,V.N., Georgaki,A., Strack,B. and Hubscher,U. (1992) Calf thymus RF-C as an essential component for DNA polymerase delta and epsilon holoenzymes function. Nucleic Acids Res 20, 4159-4165.

8.    Fotedar,R., Mossi,R., Fitzgerald,P., Rousselle,T., Maga,G., Brickner,H., Messier,H., Kasibhatla,S., Hubscher,U. and Fotedar,A. (1996) A conserved domain of the large subunit of replication factor C binds PCNA and acts like a dominant negative inhibitor of DNA replication in mammalian cells. EMBO J15, 4423-4433.

9.    Franco,A.A., Lam,W.M., Burgers,P.M. and Kaufman,P.D. (2005) Histone deposition protein Asf1 maintains DNA replisome integrity and interacts with replication factor C. Genes Dev 19, 1365-1375.

10.  Kim,H.S. and Brill,S.J. (2001) Rfc4 interacts with Rpa1 and is required for both DNA replication and DNA damage checkpoints in Saccharomyces cerevisiae. Mol Cell Biol 21, 3725-3737.

11.  Hanna,J.S., Kroll,E.S., Lundblad,V. and Spencer,F.A. (2001) Saccharomyces cerevisiae CTF18 and CTF4 are required for sister chromatid cohesion. Mol Cell Biol21, 3144-3158.

12.  Kenna,M.A. and Skibbens,R.V. (2003) Mechanical link between cohesion establishment and DNA replication: Ctf7p/Eco1p, a cohesion establishment factor, associates with three different replication factor C complexes. Mol Cell Biol23, 2999-3007.

13.  Moldovan,G.L., Pfander,B. and Jentsch,S. (2006) PCNA controls establishment of sister chromatid cohesion during S phase. Mol Cell 23, 723-732.

14.  Uchiumi,F., Watanabe,M. and Tanuma,S. (1999) Characterization of telomere-binding activity of replication factor C large subunit p140. Biochem Biophys Res Commun 258, 482-489.

15.  Kawasaki,Y., Hiraga,S. and Sugino,A. (2000) Interactions between Mcm10p and other replication factors are required for proper initiation and elongation of chromosomal DNA replication in Saccharomyces cerevisiae. Genes Cells 5, 975-989.

16.  Levin,D.S., Vijayakumar,S., Liu,X., Bermudez,V.P., Hurwitz,J. and Tomkinson,A.E. (2004) A conserved interaction between the replicative clamp loader and DNA ligase in eukaryotes: implications for Okazaki fragment joining. J Biol Chem 279, 55196-55201.

17.  Ryu,M.J., Kim,B.J., Lee,J.W., Lee,M.W., Choi,H.K. and Kim,S.T. (2006) Direct interaction between cohesin complex and DNA replication machinery. Biochem Biophys Res Commun 341, 770-775.

18.  Pan,Z.Q., Chen,M. and Hurwitz,J. (1993) The subunits of activator 1 (replication factor C) carry out multiple functions essential for proliferating-cell nuclear antigen-dependent DNA synthesis. Proc Natl Acad Sci U S A 90, 6-10.

19.  Maruyama,T., Farina,A., Dey,A., Cheong,J., Bermudez,V.P., Tamura,T., Sciortino,S., Shuman,J., Hurwitz,J. and Ozato,K. (2002) A Mammalian bromodomain protein, brd4, interacts with replication factor C and inhibits progression to S phase. Mol Cell Biol 22, 6509-6520.

20.  Anderson,L.A. and Perkins,N.D. (2002) The large subunit of replication factor C interacts with the histone deacetylase, HDAC1. J Biol Chem 277, 29550-29554.

21.  Maga,G., Mossi,R., Fischer,R., Berchtold,M.W. and Hubscher,U. (1997) Phosphorylation of the PCNA binding domain of the large subunit of replication factor C by Ca2+/calmodulin-dependent protein kinase II inhibits DNA synthesis. Biochemistry 36, 5300-5310.

22.  Munshi,A., Cannella,D., Brickner,H., Salles-Passador,I., Podust,V., Fotedar,R. and Fotedar,A. (2003) Cell cycle-dependent phosphorylation of the large subunit of replication factor C (RF-C) leads to its dissociation from the RF-C complex. J Biol Chem 278, 48467-48473.

23.  Park,M.J., Lee,M.Y., Choi,J.H., Cho,H.K., Choi,Y.H., Yang,U.S. and Cheong,J. (2007) Phosphorylation of the large subunit of replication factor C is associated with adipocyte differentiation. FEBS J 274, 1235-1245.

24.  Seybert,A., Singleton,M.R., Cook,N., Hall,D.R. and Wigley,D.B. (2006) Communication between subunits within an archaeal clamp-loader complex. EMBO J 25, 2209-2218.

25.  Trakselis,M.A. and Bell,S.D. (2004) Molecular biology: the loader of the rings. Nature 429, 708-709.

26.  Matsumiya,S., Ishino,Y. and Morikawa,K. (2001) Crystal structure of an archaeal DNA sliding clamp: proliferating cell nuclear antigen from Pyrococcus furiosus. Protein Sci 10, 17-23.

27.  Cai,J., Gibbs,E., Uhlmann,F., Phillips,B., Yao,N., O'Donnell,M. and Hurwitz,J. (1997) A complex consisting of human replication factor C p40, p37, and p36 subunits is a DNA-dependent ATPase and an intermediate in the assembly of the holoenzyme. J Biol Chem 272, 18974-18981.

28.  Skibbens,R.V. (2005) Unzipped and loaded: the role of DNA helicases and RFC clamp-loading complexes in sister chromatid cohesion. J Cell Biol 169, 841-846.

29.  Perkins,G., Drury,L.S. and Diffley,J.F. (2001) Separate SCF(CDC4) recognition elements target Cdc6 for proteolysis in S phase and mitosis. EMBO J 20, 4836-4845.

30.  Bell,S.P. (2002) The origin recognition complex: from simple origins to complex functions. Genes Dev 16, 659-672.

31.  Alleva,J.L., Zuo,S., Hurwitz,J. and Doetsch,P.W. (2000) In vitro reconstitution of the Schizosaccharomyces pombe alternative excision repair pathway. Biochemistry 39, 2659-2666.

32.  Longhese,M.P., Foiani,M., Muzi-Falconi,M., Lucchini,G. and Plevani,P. (1998) DNA damage checkpoint in budding yeast. EMBO J 17, 5525-5528.

33.  Majka,J. and Burgers,P.M. (2003) Yeast Rad17/Mec3/Ddc1: a sliding clamp for the DNA damage checkpoint. Proc Natl Acad Sci U S A 100, 2249-2254.

34.  Kim,J., Robertson,K., Mylonas,K.J., Gray,F.C., Charapitsa,I. and MacNeill,S.A. (2005) Contrasting effects of Elg1-RFC and Ctf18-RFC inactivation in the absence of fully functional RFC in fission yeast. Nucleic Acids Res 33, 4078-4089.

35.  Mayer,M.L., Gygi,S.P., Aebersold,R. and Hieter,P. (2001) Identification of RFC(Ctf18p, Ctf8p, Dcc1p): an alternative RFC complex required for sister chromatid cohesion in S. cerevisiae. Mol Cell 7, 959-970.

36.  Bylund,G.O., Majka,J. and Burgers,P.M. (2006) Overproduction and purification of RFC-related clamp loaders and PCNA-related clamps from Saccharomyces cerevisiae. Methods Enzymol 409, 1-11.

37.  Shiomi,Y., Masutani,C., Hanaoka,F., Kimura,H. and Tsurimoto,T. (2007) A second proliferating cell nuclear antigen loader complex, Ctf18-replication factor C, stimulates DNA polymerase eta activity. J Biol Chem 282, 20906-20914.

38.  Hiraga,S., Robertson,E.D. and Donaldson,A.D. (2006) The Ctf18 RFC-like complex positions yeast telomeres but does not specify their replication time. EMBO J25, 1505-1514.

39.  Shimada,M., Okuzaki,D., Tanaka,S., Tougan,T., Tamai,K.K., Shimoda,C. and Nojima,H. (1999) Replication factor C3 of Schizosaccharomyces pombe, a small subunit of replication factor C complex, plays a role in both replication and damage checkpoints. Mol Biol Cell 10, 3991-4003.

40.  Krause,S.A., Loupart,M.L., Vass,S., Schoenfelder,S., Harrison,S. and Heck,M.M. (2001) Loss of cell cycle checkpoint control in Drosophila Rfc4 mutants. Mol Cell Biol 21, 5156-5168.

41.  Ishii,H., Inageta,T., Mimori,K., Saito,T., Sasaki,H., Isobe,M., Mori,M., Croce,C.M., Huebner,K., Ozawa,K. and Furukawa,Y. (2005) Frag1, a homolog of alternative replication factor C subunits, links replication stress surveillance with apoptosis. Proc Natl Acad Sci U S A 102, 9655-9660.

42.  Ubeda,M. and Habener,J.F. (1997) The large subunit of the DNA replication complex C (DSEB/RF-C140) cleaved and inactivated by caspase-3 (CPP32/YAMA) during Fas-induced apoptosis. J Biol Chem 272, 19562-19568.

43.  Rheaume,E., Cohen,L.Y., Uhlmann,F., Lazure,C., Alam,A., Hurwitz,J., Sekaly,R.P. and Denis,F. (1997) The large subunit of replication factor C is a substrate for caspase-3 in vitro and is cleaved by a caspase-3-like protease during Fas-mediated apoptosis. EMBO J 16, 6346-6354.

44.  Cann,I.K. and Ishino,Y. (1999) Archaeal DNA replication: identifying the pieces to solve a puzzle. Genetics 152, 1249-1267.