FIGURE 8.

NAAG and ZJ43 are transported into inside-out membrane vesicles by ABCC5. A and B, 100 μm NAAG (A) or 100 μm ZJ43 (B) was incubated with control vesicles (squares) and ABCC5-containing vesicles (circles) at 37 °C, in the presence (solid line) and absence (dashed line) of 5 mm ATP. At the indicated time points, samples containing 75 μg of protein were taken. After washing over a filter, the vesicular content was analyzed by LC-MS (n = 3). C and D, various concentrations of NAAG (C) or ZJ43 (D) were incubated with control vesicles and ABCC5-containing vesicles for 10 min at 37 °C, in the presence of 5 mm ATP (n = 4). ABCC5-dependent transport was calculated and fitted to Michaelis-Menten kinetics (solid line) using GraphPad Prism. The data are presented as means ± S.E. because rare outliers resulted in a high S.D. that required a scale on which the data were not interpretable. AU, arbitrary units.