Fig. 2.

Association of ASBT-V5 fusion protein with lipid rafts in 2BT cells. 2BT cells were incubated with biotin-conjugated cholera toxin subunit B (CTxB) to label lipid rafts of plasma membrane. Labeled cells were incubated with methyl-β-cyclodextrin (MβCD) to remove cholesterol from plasma membrane or with vehicle alone. Cells were then lysed with 1% Triton X-100, and total membrane extracts were prepared as described in materials and methods. Samples were subjected to floatation on Optiprep density gradients, and fractions were collected from top of the gradients. Fractions were separated by electrophoresis and analyzed by Western blotting. A: Western blot results using anti-V5 antibodies. B: blots were probed with avidin peroxidase antibodies to label the biotinylated CTxB. C: blots were probed with actin antibodies.