Hypoxia Downregulates MAPK/ERK but Not STAT3 Signaling in ROS-Dependent and HIF-1-Independent Manners in Mouse Embryonic Stem Cells

Figure 3

Relative expressions of DUSP1 (a), DUSP5 (b), and DUSP6 (c) in hypoxia in wild-type and HIF-1α −/− ES cells. Statistical significance was determined by T test (). Effect of siRNA-mediated silencing on DUSP1 (d), DUSP5 (e), and DUSP6 (f) expression in wild-type ES cells determined by qRT-PCR. Data are presented as mean + SEM from at least three independent experiments. Statistical significance was determined by one-way analysis of variance ANOVA and post hoc Bonferroni’s multiple comparison test (). Effect of DUSP1, 5, and 6 siRNAs on ERK phosphorylation and DUSP6 levels in wild-type ES cells (g). The total level of β-actin was used as a loading control. Densitometry analysis of western blots expressed as fold change in DUSP6 protein expression (h) or ERK phosphorylation (i). Data are presented as mean + SEM from at least three independent experiments. Statistical significance was determined by one-way analysis of variance ANOVA and post hoc Bonferroni’s multiple comparison test ().

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