FIG. 5.

Effect of LPS or H₂O₂ on the half-life of GPI-PLD mRNA. (A) RAW 264.7 cells were untreated (none) or pretreated with 5 ng of LPS per ml or 0.5 mM H₂O₂ for 2 h, and then actinomycin D was added to a final concentration of 1 μg/ml. At the times indicated, total RNA was extracted and analyzed by Northern blotting. The results are representative of three independent experiments. (B) Percentage of relative level of GPI-PLD mRNA as a function of time after the addition of actinomycin D. Details of calculation are described in Materials and Methods. Results are depicted as means ± SE for three independent experiments. ∗, P < 0.05, comparing half-lives of mRNA between H₂O₂-treated and untreated control cells at 4 h.