Figure 10.

Mechanism of constitutive BSEP cycling in canalicular membrane. (A) After treatment with BFA (5 μg/ml) for 30 min at 37°C, WIF-B9 cells infected with BSEP-YFP adenovirus were used for live cell imaging by confocal microscopy at 37°C. B (bright field) and C (BSEP-YFP) show that LY294002 (200 μM) treatment for 60 min at 37°C produced vacuoles (closed arrowhead in B), which did not contain BSEP-YFP in C. (D) Quantitation of BSEP-YFP recovery in the canalicular membrane pool after various treatments. After treatment, canalicular BSEP-YFP pool was photobleached as in Figure 4A. Mean fluorescence intensity was determined as indicated. Open circles are control; solid circles are BFA (5 μg/ml); open squares are cyclic AMP (250 μM) + taurocholate (100 μM); solid squares are LY294002 (200 μM).