Fig. 1.

Aminoacylated and deacylated tRNA levels are altered in the absence of quality control by PheRS editing. (A) Representative Northern blot probed with a ³²P-5′-end–labeled tRNA^Phe probe in which aminoacylated and nonaminoacylated species are separated by an acid urea gel before transfer. (B) Percent tRNA charging levels in vivo in wild-type cells (solid bars) and in editing-deficient pheT(G318W) PheRS cells (checkered bars) grown to late log in M9 minimal medium containing no Phe, 100 µM Phe, or 10 µM m-Tyr. Error bars represent the SD from three independent experiments.