(B) Liposome tethering by purified GRAMD1b proteins. Left: Representative time course of liposome tethering, as assessed by turbidity of mixtures containing both LPM and LER together with either wild-type GRAMD1b proteins (WT), mutant GRAMD1b G187L proteins (G187L), or buffer alone as indicated. Experiments and data analysis were performed as in Fig 4. Right: Values of turbidity corresponding to the end of the experiment as indicated by the arrow (mean ± SEM, n = 3 independent experiments; Dunnett's multiple comparisons test, *P = 0.0143). 