Transfer ribonucleic acid in hepatoma tissue culture cells. II. Dexamethasone phosphate induction of tRNA^phe analyzed under cell-free conditions

It was previously shown that 10^-6 M dexamethasone phosphate induces an increase in phenylalanine acceptor activity in hepatoma tissue culture cells in vivo after a characteristic lag of about 1 hr. The authors now present data demonstrating the increase as phenylalanyl transfer RNA in an in vitro aminoacylation system. No significant alterations in phenylalanyl aminoacyl transferase were found. A general increase in other species of transfer RNA was not detected. Separation of phenylalanyl tRNA into two isoaccepting species by reverse phase chromatography revealed that the increase in phenylalanyl tRNA was restricted to only one of the two phenylalanine chargeable transfer RNAs.