FIGURE 2.
ERK and p38 activation by serum and PMA in IMLF+/+. Cell lysates of unstimulated (US) IMLF+/+ or cells stimulated with 10% serum or 100 nm PMA were prepared at given times after stimulation. Activation of ERKs or p38 (A) or phosphorylation of cPLA2α on Ser-505 (B) was determined by Western blotting using phosphospecific antibodies. Sample loading was determined using total ERK antibodies (data not shown) or antibodies to total cPLA2α (B). Results are representative of three independent experiments. C, Western blots of lysates of serum-stimulated IMLF-/- expressing either wild type ECFP-cPLA2α (WT) or EYFP-cPLA2αS505A were probed with antibodies to total cPLA2α or phosphospecific antibodies to cPLA2α phosphorylated on Ser-505. The Western blot confirms the specificity of the phosphospecific antibodies for cPLA2α phosphorylated on Ser-505.