VX-809 stabilizes the cell-surface pool of rΔF508 CFTR.

<p><b>(A)</b> ΔF508 CFTR in CFBE41o-ΔF cells were rescued to cell surface by incubating at 27°C for 48 h followed by 3 h pretreatment with 3 μM VX-809. The cells were transferred to fresh medium containing cycloheximide (CHX) with or without VX-809 that is prewarmed to 37°C and incubated at 37°C for the time periods indicated. The rescued ΔF508 CFTR (rΔF508) remained on the cell surface was measured by biotinylation as described in the Methods section. (B) The ubiquitination of rΔF508 CFTR were determined as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123131#pone.0123131.g009" target="_blank">Fig 9</a> legend. Treatment with 3 μM VX-809 inhibited the ubiquitination of rΔF508 CFTR.