A DNA Polymerase α Catalytic Subunit Is Purified Independently from the Tissues at Meiotic Prometaphase I of a Basidiomycete,Coprinus cinereus

Abstract

A 135kDa DNA polymerase α lacking primase activity has been purified to near homogeneity fromCoprinusmeiotic tissues. The activity of the DNA polymerase was sensitive to aphidicolin and N-ethylmaleimide, but was insensitive to dideoxythymidine triphosphate. DNA synthesis was proceeded with a low processivity. Neither activity nor processivity were affected by PCNA in the presence or absence of KCl. Monovalent cation inhibited its activity. These biochemical properties are almost identical to those ofCoprinusDNA polymerase α -primase complex. However, the135kDa DNA polymerase did not use activated DNA as a template-primer, inconsistent withCoprinusDNA polymerase α-primase complex. The 135kDa DNA polymerase was purified from the tissues at meiotic pro-metaphase I, suggesting that the α- DNA polymerase -primase complex dissociates as the meiotic cell cycle progresses and only the catalytic subunit remains at this stage.