Oligonucleotide extension analysis of toxin-induced 28S rRNA peptidyl transferase cleavage in RAW 264.7 cells. Cells were treated with DON (1000 ng/ml), T-2 (80 ng/ml), and ricin (160 ng/ml) for 0, 0.5, 1, 2, and 4 h. Reverse transcription reaction was performed on total RNA using FAM-labeled (A) primer 2 specific for mouse 28S rRNA specific, from 4107 to 4091) or (B) primer 3 specific for mouse 28S rRNA from 3622 to 3605 (depicted in Fig. 6). Resultant cDNA extension fragments were sized and quantified. Results are representative of two separate experiments.”