Phosphorylation of the ERK substrate p90 Rsk1 is suppressed by Tat-dn-H-Ras.

Human blood eosinophils were incubated with 100 nM Tat-dn-H-Ras and then stimulated for 7 minutes with 1 nM IL-5. Resultant cell lysates were separated by SDS-PAGE and processed for immunoblot analysis using anti–phospho-p90 Rsk1 antibody. Figure 6 is representative of 3 repetitions of this experiment.