title: Mechanism of asymmetric polymerase assembly at the eukaryotic replication fork.
abstract: Eukaryotes use distinct polymerases for leading- and lagging-strand replication, but how they target their respective strands is uncertain. We reconstituted Saccharomyces cerevisiae replication forks and found that CMG helicase selects polymerase (Pol) ɛ to the exclusion of Pol δ on the leading strand. Even if Pol δ assembles on the leading strand, Pol ɛ rapidly replaces it. Pol δ-PCNA is distributive with CMG, in contrast to its high stability on primed ssDNA. Hence CMG will not stabilize Pol δ, instead leaving the leading strand accessible for Pol ɛ and stabilizing Pol ɛ. Comparison of Pol ɛ and Pol δ on a lagging-strand model DNA reveals the opposite. Pol δ dominates over excess Pol ɛ on PCNA-primed ssDNA. Thus, PCNA strongly favors Pol δ over Pol ɛ on the lagging strand, but CMG over-rides and flips this balance in favor of Pol ɛ on the leading strand.
authors.affiliation: DNA Replication Laboratory, Howard Hughes Medical Institute, Rockefeller University, New York, New York, USA.
authors.forename: Roxana E
authors.initials: RE
authors.lastname: Georgescu
authors.affiliation: DNA Replication Laboratory, Howard Hughes Medical Institute, Rockefeller University, New York, New York, USA.
authors.forename: Lance
authors.initials: L
authors.lastname: Langston
authors.affiliation: DNA Replication Laboratory, Howard Hughes Medical Institute, Rockefeller University, New York, New York, USA.
authors.forename: Nina Y
authors.initials: NY
authors.lastname: Yao
authors.affiliation: DNA Replication Laboratory, Howard Hughes Medical Institute, Rockefeller University, New York, New York, USA.
authors.forename: Olga
authors.initials: O
authors.lastname: Yurieva
authors.affiliation: DNA Replication Laboratory, Howard Hughes Medical Institute, Rockefeller University, New York, New York, USA.
authors.forename: Dan
authors.initials: D
authors.lastname: Zhang
authors.affiliation: DNA Replication Laboratory, Howard Hughes Medical Institute, Rockefeller University, New York, New York, USA.
authors.forename: Jeff
authors.initials: J
authors.lastname: Finkelstein
authors.affiliation: DNA Replication Laboratory, Howard Hughes Medical Institute, Rockefeller University, New York, New York, USA.
authors.forename: Tani
authors.initials: T
authors.lastname: Agarwal
authors.affiliation: DNA Replication Laboratory, Howard Hughes Medical Institute, Rockefeller University, New York, New York, USA.
authors.forename: Mike E
authors.initials: ME
authors.lastname: O'Donnell
mesh_terms: D004257:DNA Polymerase II / Q000737:chemistry*; D004258:DNA Polymerase III / Q000737:chemistry*; D004261:DNA Replication; D004271:DNA, Fungal / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D004268:DNA-Binding Proteins / Q000737:chemistry; D007700:Kinetics; D064110:Minichromosome Maintenance Proteins / Q000737:chemistry; D009687:Nuclear Proteins / Q000737:chemistry; D018809:Proliferating Cell Nuclear Antigen / Q000737:chemistry; D051716:Replication Protein A / Q000737:chemistry; D017414:Ribonucleoprotein, U4-U6 Small Nuclear / Q000737:chemistry; D017415:Ribonucleoprotein, U5 Small Nuclear / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry
chemical_list: C102209:CDC45 protein, S cerevisiae; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C546594:POL30 protein, S cerevisiae; C077018:PRP8 protein, S cerevisiae; D018809:Proliferating Cell Nuclear Antigen; D051716:Replication Protein A; D017414:Ribonucleoprotein, U4-U6 Small Nuclear; D017415:Ribonucleoprotein, U5 Small Nuclear; D029701:Saccharomyces cerevisiae Proteins; D004257:DNA Polymerase II; D004258:DNA Polymerase III; D064110:Minichromosome Maintenance Proteins