RPA governs endonuclease switching during processing of Okazaki fragments in eukaryotes

Bae, Sung‐Ho; Bae, Kwang‐Hee; Kim, Jung-Ae; Seo, Yeon‐Soo

doi:10.1038/35086609

Cited by 321 publications

(544 citation statements)

References 29 publications

Supporting

Mentioning

513

Contrasting

Unclassified

Order By: Relevance

“…WRN stimulation of EXO-1 5Ј-flap cleavage may serve a function during Okazaki fragment maturation or the processing of other DNA structures at the replication fork. Evidence presented here demonstrates that WRN is able to stimulate EXO-1 cleavage of flap structures with 5Ј-ssDNA tails up to at least 10 nt, an activity that may be important in a FEN-1 independent pathway of 5Ј-flap processing (53). Alternatively, EXO-1 may play a role in the removal of the terminal ribonucleotide at the RNA-DNA junction during Okazaki fragment processing in a WRN-stimulated reaction.…”

Section: Discussionmentioning

confidence: 95%

The Exonucleolytic and Endonucleolytic Cleavage Activities of Human Exonuclease 1 Are Stimulated by an Interaction with the Carboxyl-terminal Region of the Werner Syndrome Protein

Sharma

Sommers

Driscoll

et al. 2003

Journal of Biological Chemistry

View full text Add to dashboard Cite

Exonuclease 1 (EXO-1), a member of the RAD2 family of nucleases, has recently been proposed to function in the genetic pathways of DNA recombination, repair, and replication which are important for genome integrity. Although the role of EXO-1 is not well understood, its 5 to 3 -exonuclease and flap endonuclease activities may cleave intermediates that arise during DNA metabolism. In this study, we provide evidence that the Werner syndrome protein (WRN) physically interacts with human EXO-1 and dramatically stimulates both the exonucleolytic and endonucleolytic incision functions of EXO-1. The functional interaction between WRN and EXO-1 is mediated by a protein domain of WRN which interacts with flap endonuclease 1 (FEN-1). Thus, the genomic instability observed in WRN؊/؊ cells may be at least partially attributed to the lack of interactions between the WRN protein and human nucleases including EXO-1.Werner syndrome (WS) 1 is a hereditary premature aging disorder characterized by genome instability (1). WS cells display elevated chromosomal aberrations (2-4), replication defects (3, 5-8), abnormal recombination (9, 10), altered telomere dynamics (11), and hypersensitivity to DNA-damaging agents (12-16). The gene defective in WS, designated WRN (17), encodes a protein with DNA helicase (18,19) and exonuclease (20 -22) activities which presumably functions in DNA metabolism to preserve genome integrity. To understand the basis of WS, a number of groups have investigated WRN protein interactions (for review, see Ref. 23). The collective work indicates that WRN interacts functionally with proteins implicated in replication and DNA repair including replication protein A (RPA), p53, Ku, and polymerase ␦. These studies have enabled researchers to speculate about pathways of DNA metabolism in which WRN might participate; however, the precise functions of the WRN gene product in vivo are not well understood.Recently we reported a novel interaction of WRN protein with the human 5Ј-flap endonuclease/5Ј to 3Ј-exonuclease (FEN-1) (24), a DNA structure-specific nuclease implicated in DNA replication, recombination, and repair (25). WRN protein stimulates FEN-1 cleavage activity by a physical interaction with a COOH-terminal domain of the WRN protein (24). Another member of the RAD2 family to which FEN-1 belongs is human exonuclease 1 (EXO-1) (26). Like FEN-1, EXO-1 is a structure-specific endonuclease as well as an exonuclease (27, 28). EXO-1 has been implicated in a number of DNA metabolic pathways including mismatch correction, mitotic and meiotic recombination, and double strand break repair (29 -34). A role for EXO-1 in Okazaki fragment processing during DNA replication has been suggested based on its structure-specific endonuclease and RNase H activities that are similar to those of FEN-1 (30). Functional overlap between EXO-1 and FEN-1 (Rad27 in Saccharomyces cerevisiae) has been proposed from observations in yeast that exoI: rad27 double mutants are inviable (35) and that overexpression of yeast EXO-1 or human EXO-1 co...

show abstract

Section: Discussionmentioning

confidence: 95%

The Exonucleolytic and Endonucleolytic Cleavage Activities of Human Exonuclease 1 Are Stimulated by an Interaction with the Carboxyl-terminal Region of the Werner Syndrome Protein

Sharma

Sommers

Driscoll

et al. 2003

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…It exhibits 5 0 -3 0 exonuclease activity and a structure-specific endonuclease activity by which DNA flap structures are cleaved (Harrington and Lieber, 1994). During DNA replication, Fen1 is responsible for the removal of Okazaki fragments (Bae et al, 2001). It also suppresses triplet repeat expansion generated by DNA slippage (Ruggiero and Topal, 2004) and facilitates the removal of mismatches that occur during synthesis of Okazaki fragments (Rumbaugh et al, 1999).…”

Section: Introductionmentioning

confidence: 99%

Fen1 is induced p53 dependently and involved in the recovery from UV-light-induced replication inhibition

Christmann¹,

Tomičić²,

Origer³

et al. 2005

Oncogene

View full text Add to dashboard Cite

“…Reconstitution experiments have shown that although the majority of the displaced flaps are processed by the short flap pathway, a minority require the long flap pathway. Seo and colleagues originally proposed the Dna2 pathway as the primary means of Okazaki fragment processing (Bae et al 2001). Their proposal was likely influenced by genetic evidence in S. cerevisiae that Dna2 inactivation in cells was lethal, whereas FEN1 mutants only showed a slow-growing phenotype.…”

Section: Long Flap Pathwaymentioning

confidence: 99%

“…cerevisiae Dna2 can dissociate the RPA from a long flap (Bae et al 2001;Stewart et al 2008). Using a mechanism very similar to that of FEN1, Dna2 binds the flap base, and then threads the free 5 0 end of the flap ).…”

Section: Long Flap Pathwaymentioning

confidence: 99%

See 1 more Smart Citation

Okazaki Fragment Metabolism

Balakrishnan

Bambara

2013

Cold Spring Harbor Perspectives in Biology

138

109

View full text Add to dashboard Cite

Cellular DNA replication requires efficient copying of the double-stranded chromosomal DNA. The leading strand is elongated continuously in the direction of fork opening, whereas the lagging strand is made discontinuously in the opposite direction. The lagging strand needs to be processed to form a functional DNA segment. Genetic analyses and reconstitution experiments identified proteins and multiple pathways responsible for maturation of the lagging strand. In both prokaryotes and eukaryotes the lagging-strand fragments are initiated by RNA primers, which are removed by a joining mechanism involving strand displacement of the primer into a flap, flap removal, and then ligation. Although the prokaryotic fragments are 1200 nucleotides long, the eukaryotic fragments are much shorter, with lengths determined by nucleosome periodicity. The prokaryotic joining mechanism is simple and efficient. The eukaryotic maturation mechanism involves many enzymes, possibly three pathways, and regulation that can shift from high efficiency to high fidelity.

show abstract

RPA governs endonuclease switching during processing of Okazaki fragments in eukaryotes

Cited by 321 publications

References 29 publications

The Exonucleolytic and Endonucleolytic Cleavage Activities of Human Exonuclease 1 Are Stimulated by an Interaction with the Carboxyl-terminal Region of the Werner Syndrome Protein

The Exonucleolytic and Endonucleolytic Cleavage Activities of Human Exonuclease 1 Are Stimulated by an Interaction with the Carboxyl-terminal Region of the Werner Syndrome Protein

Fen1 is induced p53 dependently and involved in the recovery from UV-light-induced replication inhibition

Okazaki Fragment Metabolism

Contact Info

Product

Resources

About