Journal: Cellular and Molecular Life Sciences: CMLS
Article Title: APOE4 triggers dysregulated synaptic vesicle release by disrupting SNARE complex assembly
doi: 10.1007/s00018-025-05787-6
Figure Lengend Snippet: APOE4 impedes the phase separation of SNARE complex. A HEK-293T cells were cotransfected with 1 µg/ml EGFP-VAMP2, EGFP-SNAP25, and EGFP- syntaxin1 plasmids for 24 h, then the represent protein condensates were photobleached. The white dashed lines indicate the photobleached area. Scale bar,10 μm. Nine droplets were selected for FRAP analysis. B Fusion and fission (yellow arrowheads) events of droplets formed by VAMP2-mCherry, syntaxin1-ECFP, and syntaxin1-ECFP fusion proteins (1 µg/ml) in conditional solution containing salt ions (1 M NaCl) and crowding reagent (PEG-8000, 10% w/v). Scale bar, 10 μm. C HEK-293T cells were cotransfected with increasing amounts (0, 2.5, or 5.0 µg/ml) of the APOE3 plasmid and the mCherry-VAMP2, EGFP-SNAP25, or syntaxin1-ECFP plasmid (1.0 µg/ml). Representative images were obtained by confocal microscopy 24 h after transfection. D Twelve cells were randomly selected for statistical analysis of droplets size. E The mixture of mCherry-VAMP2, SNAP25-EGFP, and syntaxin1-ECFP fusion proteins were added with different doses of APOE3 or APOE4 recombinant protein (0, 10, 25, and 50 ug/ml) in buffer containing crowding reagent (PEG-8000, 10% w/v) for 5 min. Representative images were obtained by confocal microscopy. F , G Quantification of the droplets number and droplets size. Eighteen fields of view were randomly selected for statistical analysis. Data information: In D , F and G , data are presented as the mean ± SEM. Scale bar: 5 μm. * p < 0.05; ** p < 0.01; *** p < 0.001
Article Snippet: C57BL/6J background female humanized APOE3- and APOE4 -TR mice were purchased from Cyagen Biosciences.
Techniques: Plasmid Preparation, Confocal Microscopy, Transfection, Recombinant