Hepatoma—foetal Phe-tRNA also present in normal rat liver

Abstract

SEVERAL groups have demonstrated independently, the presence of two isoaccepting species of Phe-tRNA in rat hepa-tcmas and only one in normal rat liver. By use of reversed phase chromatography on RPC-2 columns¹ two groups^2–4 demonstrated an early eluting, minor peak of Phe-tRNA in Morris hepatomas 5123C and 5123D, which was not seen in normal rat liver tRNA, while one group^5,6 reported the same extra peak in hepatoma 9618A but not in 3924A. We too have observed this minor peak of Phe-tRNA in Morris hepatomas 5123D, 7777 and 7800 using RPC-2 chromatography. Figure 1a shows a typical RPC-2 pattern for these three hepatomas all of which had a minor Phe-tRNA peak containing 14–15% of the total acid-precipitable counts. Recently Gonano et al. reported a similar peak of Phe-tRNA in foetal rat liver which cochromatographs on RPC-2 with the minor peak from hepatoma 5123C⁷.