Fig. 6
MiR-155-5p activates the p38 MAPK signaling pathway by targeting MSK1. A The binding target sequence of miR-155-5p on MSK1’s 3ʹ UTR exhibits conservation between humans and mice, as well as the conservation of miR-155-5p sequence between humans and mice. B, D Dual-luciferase reporter assay performed in HEK293T cells. Cells were co-transfected with dual-luciferase reporter plasmids containing the wild-type or mutant MSK1 3ʹ UTR sequence, along with NC mimic or miR-155-5p. C MSK1 expression was determined by RT-PCR in cells transfected with miR-155-5p mimic or NC mimic 24 h post-transfection. E Protein levels of MSK1, DUSP1, and p-p38MAPK were determined by Western blotting. GAPDH serves as an internal reference. P-p38MAPK/Total p38MAPK is used to assess the phosphorylation level of p38MAPK. F After co-incubation of RAW264.7 macrophages with iHvKp-derived exosomes or control exosomes for 48 h, protein expression levels of MSK1, DUSP1, and p-p38MAPK were assessed by Western blotting. GAPDH serves as an internal reference. P-p38MAPK/Total p38MAPK is used to assess the phosphorylation level of p38MAPK. G After transfection with miR-155-5p inhibitor or control for 24 h, RAW264.7 macrophages were co-incubated with iHvKp-derived exosomes, and protein expression levels of MSK1, DUSP1, and p-p38MAPK were analyzed by Western blotting. GAPDH serves as an internal reference. p-p38MAPK/Total p38MAPK is used to assess the phosphorylation level of p38MAPK. Data are presented as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, n = 3