Regulation of yeast DNA polymerase δ-mediated strand displacement synthesis by 5'-flaps.

ABSTRACT: The strand displacement activity of DNA polymerase δ is strongly stimulated by its interaction with proliferating cell nuclear antigen (PCNA). However, inactivation of the 3'-5' exonuclease activity is sufficient to allow the polymerase to carry out strand displacement even in the absence of PCNA. We have examined in vitro the basic biochemical properties that allow Pol δ-exo(-) to carry out strand displacement synthesis and discovered that it is regulated by the 5'-flaps in the DNA strand to be displaced. Under conditions where Pol δ carries out strand displacement synthesis, the presence of long 5'-flaps or addition in trans of ssDNA suppress this activity. This suggests the presence of a secondary DNA binding site on the enzyme that is responsible for modulation of strand displacement a

SUBMITTER: Koc KN 

PROVIDER: S-EPMC4417170 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature