Kinetics of induction of M-Ras in TS2 cell. TS2 cells growing in the presence of IL-2 (100 U/mL) were washed and incubated with 200 U/mL of IL-9. Two independent experiments are shown. (A) Northern blots were prepared with 10 μg of total RNA isolated from cells stimulated for the indicated times, in hours (h) or in days (d). Filters were probed with a ³²P-labeled mouse M-Ras cDNA. (B) M-Ras expression was monitored by RT-PCR and normalized with β-actin expression as described in Materials and Methods. M-Ras/β-actin ratios are arbitrary units.