Comparative aspects of ribosome-membrane interactions in rat liver and brain cortex in vitro.

The amount of incorporation of [5-3H]uridine into polyadenylated RNA was also investigated, 18h after intraperitoneal injection of precursor, in liver and spleen of mice during the late clinical stage of scrapie. Under these conditions the amount of incorporation into polyadenylated RNA in scrapie-infected mice was about 30 % of the normal value in both liver and spleen. In contrast with the results with brain, the size distribution of polyadenylated RNA from these tissues, as seen on 2.5 % polyacrylamide gels, was identical for scrapie-infected and control mice. It is noteworthy that the decrease in the labelling of polyadenylated RNA is seen in liver, because this is an organ that has very little infectivity and no known pathological abnormalities in scrapie-infected mice (Eklund et al., 1967). Further studies are required to establish the relationship between the diminished incorporation of precursor into polyadenylated RNA and the pathogenesis of scrapie.