... preferentially the phosphorylation of the p46 isoform of JNK,whereas sorbitol treatment induced phosphorylation of both the p46 and p55 isoforms. To confirm functionalactivation of the JNK signaling ... phosphorylation of the transcription factorc-JUN was attenuated. Upon expression of wild-type JSP1, a subpopula-tion of cells, with the highest levels of the phosphatase, was induced tofloat off the dish ... intrinsic phosphatase activity in the absence of myristoylation, the subcellular localization of the enzyme was altered.Compared with the wild type, the ability of nonmyristoylated JSP1 toinduce...