Figure 6

Trans-synaptic signaling has little effect on synaptic vesicle or active zone protein transport. (A) Time-lapse images of a neuroligin-1 + HcRed-expressing HEK293 cell (magenta) contacting an axon expressing synaptophysin-GFP (green). Arrows, position of individual STV in each frame. (B) Contact with neuroligin-1-expressing cells increases the mean pause duration but not instantaneous velocity of STVs inside the contact region. (C) For PTVs, neither the mean pause duration nor the instantaneous velocity was affected by neuroligin-1-induced trans-synaptic signaling. (D) Contact with SynCAM-1-expressing cells for one to four hours did not affect STV pause duration but increased their instantaneous velocity. (E) Contact with SynCAM-1 for 24 hours had no effect on STV pause duration or instantaneous velocity. (F) Contact with both neuroligin-1 and SynCAM-1 had no effect on STV pause duration or instantaneous velocity. *P < 0.05; t = time after imaging begins; error bars = SEM.