Lysine mutations inhibit WT-JMD degradation and differentially affect WT-JMD stability.

<p>(A) RFP immunofluorescence of MDCK cells transiently expressing K5R-JMD, K83R-JMD, or K5,83R-JMD under normal conditions (left column), or upon proteasome inhibition (+ MG-132). Images were processed under identical conditions and from the same experiment as images in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0037476#pone-0037476-g001" target="_blank">Figure 1D</a>. Scale bar is 25 µm. (B) MDCK cells were transiently transfected with ActA or K5,83R-JMD and incubated for 6 hours with cycloheximide, 40 hours post-transfection. Immunoblots (IB) were performed for RFP, β-catenin and GAPDH. Number(s) on the side of the gels are the apparent molecular weights of protein standards (× 10^∧3). (C) Quantification of immunoblots from MDCK cells transiently expressing ActA or K5,83R-JMD and incubated for 6 hours with cycloheximide, 40 hours post-transfection. Band intensities from post nuclear supernatants were normalized to GAPDH to account for reduction in overall protein levels. Results are averaged from 3 independent experiments (+/− s.e.m.).