Fig. 5

Over-expression of CRN5 activates the MAPK14 signalling pathway. a HEK293 cells stably over-expressing GFP for control (left upper panel) or GFP-CRN5 (right upper panel) were exposed to heat shock (0, 15, 30 min at 42 °C). Levels of Thr180/Tyr182-phosphorylated MAPK14 (pp38α) were determined by immunoblotting. Total MAPK14 (p38α, time point 0 min/without heat shock) and GAPDH of the heat shock experiment are shown for control (right lower panel). Densitometric analysis from five independent assays at time point 0 without heat shock (column chart with mean values and standard deviations; values were normalised to the GAPDH signals and indexed to GFP cells) revealed a two-fold increase of MAPK14 phosphorylation in cells expressing GFP-CRN5. b Analysis of the phosphorylation level of selected substrates downstream of MAPK14 revealed an activation of the MAPK14 pathway in GFP-CRN5 expressing HEK293 cells (Thr334-phosphorylated MAPKAPK2, Ser82-phosphorylated Hsp27, Thr71-phosphorylated ATF2, Ser392-phosphorylated p53). Loading control, see GAPDH in (a, right lower panel)