The Human IL-22 Receptor Is Regulated through the Action of the Novel E3 Ligase Subunit FBXW12, Which Functions as an Epithelial Growth Suppressor

Figure 4

FBXW12 depletion enhances cell proliferation and constitutively increases MAP kinase phosphorylation. (a) HeLa cells were transfected with FBXW12 or shRNA targeting FBXW12 (clone #4 above) and incubated with or without IL-22 (30 ng/mL). Cell counts were performed at indicated times after transfection, and viability was assessed with trypan blue staining ( by ANOVA between all groups within each IL-22 condition at 24 and 40 h for an experiment run with 5 replicates per group). (b) HeLa cells were transfected as above and lysates probed for constitutive phosphorylation of the MAP kinase JNK. (c) Transfected HeLa cells were treated with 60 ng/mL IL-22 for the indicated times and IB was performed for ERK phosphorylation at Thr202/Tyr204.

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