Figure 10. p38α^{(Y342–F348)Δ} is not autophosphorylated when expressed in yeast or in mammalian cells, but is phosphorylated by MKK6.

A. Phosphorylation levels of p38α wild type (p38α) and p38α missing amino acids Y342–F348 (p38α^{(Y342–F348)Δ}) were tested when expressed in hog1Δpbs2Δ strain, before (−) and 10 minutes after (+) exposure to 1 M NaCl. B. Human embryonic kidney 293 cells were trasnfected with the indicated plasmids. Forty-eight hours after transfections cells lysates were prepared and analyzed by Western blots using the indicated antibodies. All p38 constructs are HA-tagged whereas MKK6^EE is flag-tagged. MK2 ( =  MAPKAPK2) is a substrate of p38α.