Fig. 3.

L1, L2, and L3 of ILY do not insert into cholesterol-depleted membranes. Each D4 loop was substituted with a cysteine, modified with NBD, and the fluorescence emission was independently determined for each in the absence or presence of native or cholesterol-depleted hRBC ghost membranes. (a–c) ILY^A428C-NBD (a), ILY^A464C-NBD (b), or ILY^L518C-NBD (c) was incubated alone (solid line), with hRBCs (dashed line), or with hRBCs depleted of cholesterol (dotted line). (d–f) Membrane cholesterol was then restored, and insertion was determined for ILY^A428C-NBD (d), ILY^A464C-NBD (e), or ILY^L518C-NBD (f) alone (solid line) or after incubation with cholesterol-replete membranes (dotted line).