STIMULATION OF THE NUCLEAR URACIL DNA GLYCOSYLASE IN PROLIFERATING HUMAN-FIBROBLASTS

Abstract

The cell cycle stimulation of individual species of the uracil DNA glycosylase was examined in WI-38 normal diploid fibroblasts. The nuclear uracil DNA glycosylase was induced as WI-38 cells traversed the cell cycle. The specific activity of the mitochondrial glycosylase remained constant during cell proliferation. The 2 enzyme activities can be further distinguished by their elution patterns on DNA-cellulose, by differential cation sensitivity and by kinetic differences. The singular stimulation of the nuclear glycosylase in the cell cycle is a further suggestion that normal human cells actively regulate excision repair pathways.