(H, I) Liposome sedimentation assays of wild-type GRAM1b (WT) and mutant GRAM1b (G187L). Liposomes containing the indicated mole% lipids were incubated with purified GRAM1b proteins as shown. Bound proteins [pellet, (P)] were separated from the unbound proteins [supernatant, (S)], run on SDS-PAGE and visualized by colloidal blue staining [mean ± SEM, n = 3 independent experiments for all the conditions; (H) Left (10% PS): Holm-Sidak t-test for multiple comparisons, *P = 0.022679 at 40% cholesterol, **P = 0.009195 at 50% cholesterol. Right (20% PS): Holm-Sidak t-test for multiple comparisons, *P = 0.023163 at 30% cholesterol, **P = 0.000327 at 40% cholesterol, *P = 0.017194 at 50% cholesterol. (I) Holm-Sidak t-test for multiple comparisons, n.s. denotes not significant, **P < 0.000001 at 50% DOPC, 50% cholesterol, *P = 0.011271 at 40% DOPC, 60% cholesterol]. DOPC, phosphatidylcholine (1,2-dioleoyl-sn-glycero-3-phosphocholine); DOPS, phosphatidylserine (1,2-dioleoyl-sn-glycero-3-phospho-L-serine); Chol., cholesterol. 