Do DNA polymerases δ and α act coordinately as leading and lagging strand replicases?

Abstract
The activity ratio of DNA polymerases δ and α in calf thymus was found to be invariably 1:1, irrespective of extraction procedure (8 types) and subcellular localization (cytoplasm, nucleus and microsomes). This was established by separation of the two forms by hydroxyapatite chromatography and by their response to specific inhibitors and monoclonal antibodies. This finding supports the dimeric DNA polymerase model [(1980) J. Biol. Chem. 255, 4290–4303], which proposes that DNA polymerases δ and α act coordinately as leading and lagging strand enzymes, respectively, at the replication fork.