DNA synthesis and the effect of sucrose in nuclei of host liver and Morris hepatomas.

about 6 times increased over that with host liver in both systems, and incorporation with hepatoma 7777 is about 10 times that with host liver in both the in vivo and in vitro systems. Addition of sucrose to the incubation mixture (0.8 M final concentration) increases incorporation in host liver nuclei twoto threefold but has no effect on hepatoma nuclei. This difference in response to a more dense incubation medium between host and hepatoma nuclei might be due to differences in the nuclear membranes. With about equal amounts of RNA and protein per mg DNA in the three different nuclear preparations, hepatoma nuclei contain two to three times more phospholipid per mg DNA than do host liver nuclei.