[Replication of DNA associated with nuclear envelope of regenerating rat liver]

DNA associated with nuclear envelopes was isolated from rat liver nuclear lysate using centrifugation in sucrose gradient. The specific radioactivity of DNA obtained in nuclear envelope was compared with that of overall nuclear DNA at different stages of the S-period after partial hepatectomy and 1-15 min following intravenous injection of 3H-thymidine. It was found that at various steps of the cell cycle (19, 24 and 27 hrs following partial hepatectomy) the specific radioactivities of nuclear membrane-linked and overall nuclear DNAs do not show any significant differences. No noticeable selective synthesis or initiation of DNA replication on the nuelear envelope were observed either.