KIF1A and KIF13B tails bind low-density lipoprotein receptor vesicles. (A) The three constructs expressed in this assay before and after assembly of the split kinesin. (B–I) Kymographs illustrating axonal transport of LDLR-GFP vesicles in hippocampal neurons expressing different split kinesin tail constructs. The kymographs show the transport of LDLR vesicles in the axon before (0 min) and 13–21 min after addition of the linker drug. There was no change in the overall transport of TfR vesicles when KIF1Bα, KIF1Bβ, KIF13A, KIF5C, KIF17, or KIF21B tails were expressed. In contrast, there was a large increase in the long-range anterograde transport events of LDLR vesicles when KIF1A (B) or KIF13B (F) tails were used. (J) 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 LDLR vesicles was observed in cells expressing FRB-KIF1A and FRB-KIF13B tails (Wilcoxon signed rank test; P < 0.01). n = 7–11 cells per condition. Time and distance calibration are the same for all kymographs.