Fig. 6.

CD9 overexpression and depletion reduce ERK1/2 phosphorylation in HeLa cells. a HeLa cells were transfected either with control (ctr.) or with CD9-expression plasmid for 24 h. The next day cells were starved for 1 h in medium without FCS and afterwards, the lysates were collected. b Quantification of WB shown on a. c HeLa cells were transfected either with control (ctr. si) or with CD9-specific siRNA. Two days later cells were starved for 1 h in medium without FCS and the lysates were collected. d Quantification of WB shown on c. a–d WB shows phosphorylated and total ERK1 and ERK2 for the indicated conditions; α-tubulin was used as a loading control. The amount of phosphorylated ERK1 (black) and ERK2 (grey) is shown as a ratio of phosphorylated to total ERK form. The values are given as mean ± SEM and the mean for ERK1 and ERK2 for the control was set to 100%. Data for ERK1 and ERK2 after CD9 manipulation compared to the corresponding ERK1 and ERK2 of the control condition were analysed with two-tailed unpaired t test (*p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001, ns not significant). Overexpression experiments were repeated independently at least two times with total n = 6 for control and n = 5 for CD9