1979 Volume 85 Issue 6 Pages 1551-1554
Poly(dT) products which were synthesized depending on (rA)n•(dT)12-18 as a template-primer by mammalian DNA polymerases β and γ were analyzed by alkaline sucrose gradient centrifugation. The size of the population of poly(dT) chains synthesized by DNA polymerase β increased slowly and consistently during incubation up to at least 30min. On the other hand, the product size with DNA polymerase γ reached the final size (7s) within 5min and the number of products increased during further incubation. Comparison of product number per enzyme molecule suggests that DNA polymerase β acts on multiple primers in a distributive fashion while DNA polymerase r completes poly(dT) chains of large size in a one-by-one fashion.