Figure 3.

ERKs and p38 are negatively regulated by MKP1 in macrophages. (A) Effects of Dusp1 interference on downstream MAPKs members. The lentivirus carrying M_Dusp1-shRNA and Dusp1-Vector-NC was designed and inserted into RAW264.7 cells. The phosphorylation levels of ERK1/2, ERK5, and p38 were measured 12 h later by Western blot. (B) Investigation on the phosphorylation level of downstream MAPKs members. Dusp1 WT and knockdown cells were pretreated with 20 μM PUN for 3 h and then treated with 1 μg/ml LPS for 12 h, as indicated. The phosphorylation level of each MAPKs members was detected via phospho-proteomics approach. Three independent experiments were performed. The proteins with fold changes (in log2 value, of control group) higher than 1.2 are listed in the heatmap. (C) Identification of the phosphorylation of MAPKs members. Dusp1 WT and knockdown cells were pretreated with 20 μM PUN for 3 h and then treated with 1 μg/mL of LPS for 12 h, as indicated. The phosphorylation level of each MAPK member was detected via Western blot. Data are expressed as mean ± SD of three independent experiments. **p < 0.01 indicates statistically significant differences between indicated groups.