Skip to main content
. 2001 Jan;21(1):61–72. doi: 10.1128/MCB.21.1.61-72.2001

FIG. 2.

FIG. 2

dsRNA-triggered phosphorylation, polyubiquitinylation, and proteosome-mediated degradation of IκBs in both pkr+/+(EX12) and pkr0/0(EX12) MEF. (A) pkr+/+(EX12) and pkr0/0(EX12) MEF were treated with Lipofectin alone (lanes Control) or with pI-pC (10 μg/ml) in the presence of Lipofectin (lanes dsRNA). Note that the same procedure for Lipofectin treatment (with or without pI-pC) applies to all experiment presented in Fig. 2 to 9 and is described in Materials and Methods. At 1 h after the treatment, the cells were harvested and processed for immunoblot analysis of IκBα using either a phospho-(Ser32)-IκBα-specific antibody (upper panels) or an IκBα-specific antibody (lower panels). Treatment of cells with Lipofectin does not affect IκBβ or any other NFκB-related signaling pathway investigated in this work (data not shown). (B) pkr+/+(EX12) and pkr0/0(EX12) MEF were treated as in panel A, except that, where indicated, the cells were pretreated for 25 min with benzyloxycarbonyliso-leucyl-glutamyl(OtBu)-alanyl-leucine aldehyde (IEAL), benzyloxycarbonyl-leucyl-leucyl-leucine aldehyde (LLL), or the respective solvents for each of them, methanol (MeOH) or dimethyl sulfoxide (DMSO). IκBβ steady-state levels were monitored in an immunoblot analysis.