Fig. 2: Overexpression of N-cadherin-CTF1 slows synaptic vesicle endocytosis.
From: A delay in vesicle endocytosis by a C-terminal fragment of N-cadherin enhances Aβ synaptotoxicity
A Time courses of SypHy fluorescence changes (elicited by 400 stimuli at 20 Hz; indicated by blue bar) in control neurons (black trace), in N-cadherin-CTF1 expressing neurons (orange trace), and in N-cadherin-CTF1 expressing neurons with addition of L-685,485 (5 µM for 2 days; magenta trace). Individual SypHy puncta on a given neuron were averaged per cell and normalized to the NH4Cl signal. B The maximal SypHy fluorescence signal did not significantly differ between control and N-cadherin-CTF1 expressing neurons. Left and middle panel: SypHy puncta of each cell (control: n = 10; N-cadherin-CTF1 expressing: n = 10; N-cadherin-CTF1 expressing with addition of L-685,485: n = 10) were averaged. Individual values for each cell (left) and mean ± SEM (middle) are shown. Right panel: Cumulative distributions of individual SypHy puncta of all cells recorded (control: n = 128 puncta; N-cadherin-CTF1 expressing: n = 66 puncta; N-cadherin-CTF1 expressing with addition of L-685,485: n = 77 puncta). C The percent loss of the SypHy signal (% endocytosis) 90 s after end of stimulation was significantly reduced in N-cadherin-CTF1 expressing neurons. Left and middle panel: SypHy puncta of each cell were averaged. Right panel: Cumulative distributions of individual SypHy puncta of all cells recorded. D The decay time constant of SypHy fluorescence decay was significantly increased in N-cadherin-CTF1 expressing neurons. Monoexponential fit of the average time course of SypHy signals from all puncta of a given cell (A) was used. Individual values for each cell (left) and mean ± SEM (right) are shown. One-way ANOVA with Tuckey’s post hoc test; **P < 0.01.
