Figure 2. The hyperosmotic expression of the C9 gene is induced by the stimulation of gene transcription. The mRNA level was determined
with real-time RT–PCR analysis. A: Inhibition of the RNA polymerase II by actinomycin D (ActD; 5 µg/ml) abrogated C9 gene expression induced by hyperosmotic
(+ 100 mM NaCl) medium. The data were obtained after 6 h of stimulation. Actinomycin D was preincubated for 30 min. B: The stability of C9 mRNA did not significantly differ between isosmotic (control) and hyperosmotic (+ 100 mM NaCl) conditions.
The cells were first treated with iso- and hyperosmotic media for 2 h, followed by the addition of actinomycin D (5 µg/ml).
Total RNA was isolated at different time periods after the addition of actinomycin D. Means ± SEM of four independent experiments
using cell lines from different donors. Significant difference versus isosmotic control: *p<0.05. Significant difference versus
NaCl control: ●p<0.05. Significant difference versus 0 h control: ○p<0.05.