PFIC II mutations have a heterogeneous effect on the localization of Bsep-GFP in MDCK cells. MDCK cells were transiently transfected with wild-type (WT) Bsep-GFP (a) or Bsep PFIC II mutants (b–h) for 72 hours and imaged by confocal microscopy. In each panel, the top part shows the en face image and the bottom part shows the Z-sectioning image. Bar, 10 μm.