EFFECT OF 3'-DEOXYADENOSINE AND 3'-AMINO-3'-DEOXYADENOSINE ON LABELLING OF RNA SUB-SPECIES IN EHRLICH ASCITES TUMOR CELLS

3′-Deoxyadenosine and 3′-amino-3′-deoxyadenosine exert a differential inhibitory effect on the labelling of nucleochromosomal and cytoplasmic RNA. When these RNA's are further separated into sub-species it is shown that 28-S and 18-S cytoplasmic RNA are very strongly inhibited, whereas 50-60-S nuclear RNA is only slightly inhibited. This 50-60-S nuclear RNA is very rapidly labelled, has a high specific activity, a short half-life and is presumed to serve an intra-nuclear function. A differential inhibition of 32-35-S, 28-S and 18-S RNA, and cytoplasmic 4-5-S RNA is also demonstrated. © 1969.