Induction of DNA ligase during stimulation of DNA synthesis in intact rat liver by a dietary manipulation

Abstract

After a nutritional shift from a protein-free to a diet containing 50% casein, the activity of DNA ligase increases in intact rat liver in correlation with the induction of hepatic DNA replication. The treated rat liver as well as control rat liver contains a single species of DNA ligase having a sedimentation coefficient of about 5.5 S. The administration of cycloheximide in vivo completely inhibits the increase in DNA ligase activity and in DNA synthesis, indicating that DNA ligase is induced in the hepatic cells replicating DNA. In contrast to DNA ligase, DNA kinase is unchanged in the activity level by the dietary manipulation.