Quantification of changes in TfR vesicle traffic in neurons expressing different split kinesin tails. The figure plots the difference in the amount of anterograde transport before and 15–30 min after adding linker drug (number of anterograde events after drug minus number of anterograde events before drug; mean ± SEM). A statistically significant increase in axonal transport of TfR vesicles was observed in cells expressing FRB-KIF13A and FBR-KIF13B tails (Wilcoxon signed rank test; P < 0.01). n = 7–16 cells per condition.