Extended Data Fig. 3: The negatively charged phosphatidylserine (PS) is important in α-Syn-induced clustering.
From: VAMP2 chaperones α-synuclein in synaptic vesicle co-condensates
(a) Experimental scheme of single-vesicle assay for monitoring vesicle clustering. A saturated layer of DiI-labeled SVM was immobilized on an imaging surface via biotin–NeutrAvidin interactions. After free-floating DiD-labeled SVM was injected into the sample chamber, clustering in the presence or absence of α-Syn was determined by counting the number of spots arising from the fluorescence emission of DiD upon excitation at 633 nm. (b) The numbers of interacting DiD-labeled, protein-free SVMs—with or without PS—interacting on the imaging surface was assessed both in the presence of α-Syn or not. (c) The numbers of interacting DiD-labeled, full-length VAMP2 reconstituted SVMs—with or without PS—interacting on the imaging surface was assessed both in the presence of α-Syn or not. (b-c) Bar graphs: quantification of interacting vesicles; data are means ± SD; unpaired two-tailed t-test; n (left to right) = 8, 20, 25, 12, or 16, 16, 16, 16 for (b) or (c), respectively; n refers to the number of random imaging locations in the same channel. (d) Residue-resolved relative NMR signal intensity ratios (I/I0) of α-Syn titrated by DOPC liposome at indicated protein/lipid molar ratios. Dashed lines highlight the residue positions 30 and 95. Source numerical data is available in the Source Data Extended Data Fig. 3.
