Figure 5.

H₂O₂ induces ubiquitination and proteasome degradation of zebrafish Dusp6. (A-B) Exogenous H₂O₂ decreased the expression level of Myc-tagged zDusp6 in a dose-dependent manner in HeLa cells as evidenced by western blotting (A). The statistics of A is shown in B. β-actin was used for normalizing protein loading. (C-D) Exogenous H₂O₂ decreased the expression level of endogenous zDusp6 in a dose-dependent manner in zebrafish embryos at 24 hpf (C), and the statistics of C is shown in D. β-actin was used for normalizing protein loading. (E) Ub-zDusp6 (arrowhead) was detected after H₂O₂ and/or MG132 treatments in HeLa cells overexpressing Myc-tagged zDusp6 and Flag-tagged ubiquitin (Ub-Flag). Myc-tagged Dusp6 proteins were detected for all groups except the group without zDusp6-Myc overexpression.