5’ flap endonuclease and helicase involved in processing Okazaki fragments





Molecular weight







Biochemical properties


• Helicase/DNA dependent ATPase/exonuclease (1)   

•Helicase 5’ to 3’ (2) stimulated by RNA at the end of the DNA.



•helicase reported less active than yeast in vitro (3)




Protein interactions


• Fen1 (1)

• Tor (genetic ) (4)

• Ctf4 (genetic) (5) DNA2 partly degraded in cells lacking ctf4.

•Rpa (genetic) (6) and direct (7)



• Cdc24 genetic (8)







Cellular location and expression


Other comments


•Associates with telomeres via sir3 (9)

•some effect on lifespan (10)




•can complement yeast mutant (3)





•Human homologues (11) (12)



Revised by


Last edited

13 April 08



1.    Budd,M.E. and Campbell,J.L. (1995) A yeast gene required for DNA replication encodes a protein with homology to DNA helicases. Proc Natl Acad Sci U S A 92, 7642-7646.

2.    Bae,S.H. and Seo,Y.S. (2000) Characterization of the enzymatic properties of the yeast dna2 Helicase/endonuclease suggests a new model for Okazaki fragment processing. J Biol Chem 275, 38022-38031.

3.    Liu,Q., Choe,W. and Campbell,J.L. (2000) Identification of the Xenopus laevis homolog of Saccharomyces cerevisiae DNA2 and its role in DNA replication. J Biol Chem 275, 1615-1624.

4.    Fiorentino,D.F. and Crabtree,G.R. (1997) Characterization of Saccharomyces cerevisiae dna2 mutants suggests a role for the helicase late in S phase. Mol Biol Cell 8, 2519-2537.

5.    Formosa,T. and Nittis,T. (1999) Dna2 mutants reveal interactions with Dna polymerase alpha and Ctf4, a Pol alpha accessory factor, and show that full Dna2 helicase activity is not essential for growth. Genetics 151, 1459-1470.

6.    Bae,S.H., Kim,J.A., Choi,E., Lee,K.H., Kang,H.Y., Kim,H.D., Kim,J.H., Bae,K.H., Cho,Y., Park,C. and Seo,Y.S. (2001) Tripartite structure of Saccharomyces cerevisiae Dna2 helicase/endonuclease. Nucleic Acids Res 29, 3069-3079.

7.    Bae,K.H., Kim,H.S., Bae,S.H., Kang,H.Y., Brill,S. and Seo,Y.S. (2003) Bimodal interaction between replication-protein A and Dna2 is critical for Dna2 function both in vivo and in vitro. Nucleic Acids Res 31, 3006-3015.

8.    Tanaka,H., Tanaka,K., Murakami,H. and Okayama,H. (1999) Fission yeast cdc24 is a replication factor C- and proliferating cell nuclear antigen-interacting factor essential for S-phase completion. Mol Cell Biol 19, 1038-1048.

9.    Choe,W., Budd,M., Imamura,O., Hoopes,L. and Campbell,J.L. (2002) Dynamic localization of an Okazaki fragment processing protein suggests a novel role in telomere replication. Mol Cell Biol 22, 4202-4217.

10.  Hoopes,L.L., Budd,M., Choe,W., Weitao,T. and Campbell,J.L. (2002) Mutations in DNA replication genes reduce yeast life span. Mol Cell Biol 22, 4136-4146.

11.  Masuda-Sasa,T., Imamura,O. and Campbell,J.L. (2006) Biochemical analysis of human Dna2. Nucleic Acids Res 34, 1865-1875.

12.  Kim,J.H., Kim,H.D., Ryu,G.H., Kim,D.H., Hurwitz,J. and Seo,Y.S. (2006) Isolation of human Dna2 endonuclease and characterization of its enzymatic properties. Nucleic Acids Res 34, 1854-1864.