DNA polymerase delta isolated from Schizosaccharomyces pombe contains five subunits

Proc Natl Acad Sci U S A. 1997 Oct 14;94(21):11244-9. doi: 10.1073/pnas.94.21.11244.


DNA polymerase delta (pol delta) plays an essential role in DNA replication, repair, and recombination. We have purified pol delta from Schizosaccharomyces pombe more than 10(3)-fold and demonstrated that the polymerase activity of purified S. pombe pol delta is completely dependent on proliferating cell nuclear antigen and replication factor C. SDS/PAGE analysis of the purified fraction indicated that the pol delta complex consists of five subunits that migrate with apparent molecular masses of 125, 55, 54, 42, and 22 kDa. Western blot analysis indicated that the 125, 55, and 54 kDa proteins are the large catalytic subunit (Pol3), Cdc1, and Cdc27, respectively. The identity of the other two subunits, p42 and p22, was determined following proteolytic digestion and sequence analysis of the resulting peptides. The peptide sequences derived from the p22 subunit indicated that this subunit is identical to Cdm1, previously identified as a multicopy suppressor of the temperature-sensitive cdc1-P13 mutant, whereas peptide sequences derived from the p42 subunit were identical to a previously uncharacterized ORF located on S. pombe chromosome 1.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Blotting, Western
  • Chromatography, Affinity
  • Chromatography, Gel
  • Chromatography, Ion Exchange
  • DNA Polymerase III / chemistry*
  • DNA Polymerase III / isolation & purification
  • DNA Polymerase III / metabolism*
  • DNA Replication
  • DNA, Fungal / metabolism
  • DNA-Binding Proteins / metabolism
  • Electrophoresis, Polyacrylamide Gel
  • Homeodomain Proteins*
  • Humans
  • Kinetics
  • Macromolecular Substances
  • Minor Histocompatibility Antigens
  • Molecular Sequence Data
  • Molecular Weight
  • Proliferating Cell Nuclear Antigen / pharmacology
  • Proto-Oncogene Proteins c-bcl-2*
  • Replication Protein C
  • Repressor Proteins*
  • Saccharomyces cerevisiae Proteins*
  • Schizosaccharomyces / enzymology*


  • BCL2-related protein A1
  • DNA, Fungal
  • DNA-Binding Proteins
  • Homeodomain Proteins
  • MATA1 protein, S cerevisiae
  • Macromolecular Substances
  • Minor Histocompatibility Antigens
  • Proliferating Cell Nuclear Antigen
  • Proto-Oncogene Proteins c-bcl-2
  • Repressor Proteins
  • Saccharomyces cerevisiae Proteins
  • DNA Polymerase III
  • Replication Protein C