Figure 1
Extracellular Syns decrease actin mobile fraction.
(a) F-actin distribution, as revealed by fluorescent phalloidin staining, in 2 DIV mouse embryonic hippocampal neurons incubated in the absence or presence of 5 μM purified wt or A30P Syn for 2 days. (b) Neurons infected with actin-YFP were bleached along the axon (left panel, square) and imaged at 3 DIV at 1 frame/0.6 s for 60 s (right panel). (c) Mean curves of actin-YFP fluorescence recovery after photobleaching over time in control (blue), wt Syn (green) and A30P Syn (red)-treated neurons, notice the lower value of the plateau in the curves obtained from Syns-treated neurons. (d) Quantitative evaluation of the percentage of mobile fraction over the total fluorescence and of the time constant of fluorescence recovery (e) in control and in neurons treated with Syns as in (a). In (d, e) data are expressed as mean values ± SEM. In (c–e), ctrl, n = 19, wt Syn, n = 24; A30P Syn, n = 24, from 3 independent cultures. Statistical significance determined by one-way ANOVA followed by Dunnett’s test for multiple comparison, *P < 0.05; **P < 0.01. (d) P = 0.0046, alpha value: 0.050:0.791; (e) P = 0.5170 n.s., alpha value: 0.050:0.049). Bars in (a, b) 10 μm.
