IDENTIFICATION OF GAMMA-LIKE DNA-POLYMERASE FROM SEA-URCHIN EMBRYOS

A γ-like DNA polymerase devoid of DNA polymerase-α and -β activities was prepared from the nuclear fraction of blastulae of the sea urchin, Hemicentrotus pulcherrimus. The enzyme sedimented at the position of an approximate sedimentation coefficient of 3.3 S under high salt conditions by sucrose gradient centrifugation. An isoelectric point was determined to be pH 5.8. The enzyme activity was sensitive to sulfhydryl blocking reagents. Poly(rA) · oligo (dT)12-18 followed by poly(dA) · oligo(dT)12-18 was effectively utilized as a template-primer. From the above results, this polymerase seems to resemble the vertebrate DNA polymerase-γ. © 1979.