A Global Profile of Replicative Polymerase Usage

Nat Struct Mol Biol. 2015 Mar;22(3):192-198. doi: 10.1038/nsmb.2962. Epub 2015 Feb 9.

Abstract

Three eukaryotic DNA polymerases are essential for genome replication. Polymerase (Pol) α-primase initiates each synthesis event and is rapidly replaced by processive DNA polymerases: Polɛ replicates the leading strand, whereas Polδ performs lagging-strand synthesis. However, it is not known whether this division of labor is maintained across the whole genome or how uniform it is within single replicons. Using Schizosaccharomyces pombe, we have developed a polymerase usage sequencing (Pu-seq) strategy to map polymerase usage genome wide. Pu-seq provides direct replication-origin location and efficiency data and indirect estimates of replication timing. We confirm that the division of labor is broadly maintained across an entire genome. However, our data suggest a subtle variability in the usage of the two polymerases within individual replicons. We propose that this results from occasional leading-strand initiation by Polδ followed by exchange for Polɛ.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA / chemistry
  • DNA Polymerase I / physiology*
  • DNA Polymerase II / physiology*
  • DNA Polymerase III / physiology*
  • DNA Replication / physiology*
  • Models, Genetic*
  • Replication Origin
  • Schizosaccharomyces / genetics*

Substances

  • DNA
  • DNA Polymerase I
  • DNA Polymerase II
  • DNA Polymerase III

Associated data

  • GEO/GSE62108