Protein Arginine Methyltransferase 1 Interacts with and Activates p38α to Facilitate Erythroid Differentiation
Figure 3
The PRMT1-mediated effect on erythroid differentiation required the activation of p38 MAPK.
(A) Phosphorylation of p38 MAPK was stimulated upon araC and NaB treatment in parental K562 cells. Significantly higher levels of p38 MAPK activation were observed in the PRMT1-overexpressing R2–1 cell clone. The levels of phospho-p38 were compared to those detected in control K562 cells without stimulation. Data are presented as means ± S.E. of three independent experiments. (B) In contrast, the activation of p38 MAPK was greatly reduced in PRMT1-knockdown KD-2 cells, as examined by an in vitro kinase assay using ATF-2 as the substrate. (C) The pharmacological inhibitor of p38 MAPK, SB203580, inhibited erythroid differentiation of parental K562 cells and R2–1 cells. All results shown are representative of three separate experiments. Differentiation results are presented as means ± S.E. of three repeats; *, p<0.05; **, p<0.01; ***, p<0.005 compared with K562 control cells.
