Figure 8: TAK1 and p38 MAPK are involved in cell deaths of A20 knockdown cells.
From: Smad6 inhibits non-canonical TGF-β1 signalling by recruiting the deubiquitinase A20 to TRAF6
(a) AML-12 cells were pre-treated with 10 uM 5Z-7-oxozeaenol (5Z-7-oxo; TAK1 inhibitor), 10 uM SP600125 (JNK inhibitor), or 20 uM SB203580 (p38 MAPK inhibitor) for 30 min and subsequently treated with TGF-β1 for 30 min. The activity of each inhibitor was monitored through detecting expression of phospho-TAK1, phospho-JNK (or phospho-c-Jun), or phospho-p38 MAPK by immunoblotting (IB), respectively. The optimal concentrations of each inhibitor were obtained by repeating these experiments several times. DMSO-containing buffers were used as a negative control. (b) AML-12 cells expressing GFP-specific shRNA or A20-specific shRNA (shA20#3) were pre-treated with each inhibitor for 30 min and subsequently treated with TGF-β1 for 36 h under serum-starved conditions. Cells were analysed by flow cytometry and the percentage of subG1 fraction indicated. (c) Percentages of the subG1 fraction are summarized in a bar graph. The data are means ± s.d. (**P<0.01, ***P<0.001, t-test; n=3).
