FIGURE 5:

NPC1L1-GFP endocytosis does not require cholesterol binding to the N-terminal domain’s cholesterol-binding site. (A) The [³H]cholesterol binding to purified, soluble NPC1L1 N-terminal domain for wild-type and L216A mutant proteins. Inset, SDS–PAGE of soluble domains used; numbers represent molecular mass in kilodaltons. (B, C) Kinetics of internalization of wild-type or NPC1L1 L216A protein (B; four separate experiments in duplicate) or NPC1L1ΔN (C; one experiment in quadruplicate) as described and determined in Figure 3 except that 7% input is shown in the insets. Error bars represent SEM.