Fig. 1.
DUSP5 propagates cytoplasmic ERK signaling. Serum-starved primary MEFs from WT or Dusp5 KO mice were infected with either 0.3–3.0 pfu/nL Ad ERK-responsive EGR1 promoter-driven DUSP5-Myc (DUSP5) or a KIM mutant of DUSP5-Myc (DUSP5R53/54A) and stimulated with 20% (vol/vol) FBS for times indicated. (A) Representative confocal images of p-ERK and ERK are shown. (Scale bar: 60 μm.) (B) HCM was used to quantify >104 cells per condition per experiment for levels of Myc tag, nuclear (Nuc), or cytoplasmic (Cyt) p-ERK intensity, or N:C of total ERK fluorescence. Data are normalized mean arbitrary fluorescence unit (AFU) values ± SEM, n = 4–8, *P < 0.05, **P < 0.01, ****P < 0.0001 comparing WT vs. KO using two-way repeated-measures ANOVA and Bonferroni posttest. Note: KO data are identical in Upper and Lower plots. (C) Western blots of whole-cell lysates are shown for total ERK, p-ERK, β-tubulin, and DUSP5. A representative blot is shown from n = 3 similar experiments; blot quantification is shown in Fig. S1C.