Figure 5.

ERK phosphorylation of Txnip Thr³⁴⁹ regulates cytokine-induced degradation. A549 cells were infected with lentivirus expressing either FLAG-tagged Txnip_WT or Txnip_349V. The cells were treated with CHX (50 μm) and ERK1/2 MAP kinase inhibitor (EI) (U0126, 10 μm) for 10 min prior to stimulation with TNFα (10 ng/ml). A, immunoblots of Txnip at indicated time post-CHX treatment. 0-min blots for the Txnip_349V CTL/EI group and TNFα/TNFα-EI group are duplicates, which serve as the respective controls for those groups because they were run on the same gel. B, densitometric analysis of Txnip blots shown in A. The results are relative to CHX-only control (CTL) at 0-min treatment time (n = 3 per condition). **, p < 0.01 EI + TNFα compared with TNFα alone.