the strong reduction of in vitro pre-rrna synthesis can partially be reversed by pre-treatment of the starved cells with low concentrations of cycloheximide , but not with puromycin. -- ( 2 ) the processing time of nuclear pre-rrna is considerably prolonged and the introduction of the central hidden break into newly synthesized cytoplasmic 26s rrna is strongly delayed , as shown by methionine pulse-chase experiments. -- ( 3 ) the accumulation rate of cytoplasmic rrna is 1 to 2 % of the rate in optimally growing cells , as determined from the specific radioactivity of atp at saturation with labelled exogeneous adenosine and the changes of the specific radioactivity of the amp residues in rrna as well as from the rrna turnover rate .
C0034145
puromycin
C0001443
adenosine