Increased cell surface expression of rescued ΔF508 CFTR (rΔF508 CFTR) following μ2 and Dab2 depletion.

<p>The consequences of μ2 depletion and Dab2 depletion on total ΔF508 CFTR expression (<b>A</b> and <b>B</b>) and on surface rΔF508 CFTR expression (<b>C</b> and <b>D</b>). CFBE41o-ΔF cells were transfected with 20 nM siRNA duplexes targeted specifically to μ2 or Dab2 or control (C) siRNA. 48 h after transfection, the control and siRNA depleted cells were cultured for an additional 24 h at 27°C to promote ΔF508 CFTR delivery to the cell surface. 72 h after transfection, 25 μg of cell lysates were separated by SDS-PAGE and immunoblotted using anti-CFTR, anti-μ2 and anti-Dab2 antibodies. β-actin was blotted as loading control. The changes in μ2, Dab2 and rΔF508 CFTR levels following siRNA depletion are indicated below the blots. Cell surface expression of rΔF508 CFTR was monitored by biotinylation as described in the Experimental section. The molecular mass in kDa is indicated on the right-hand side of each panel.