Figure 3.

A motility assay using liposomes recapitulates single-molecule data. (A) A schematic of the liposome motility assay. Rab6a was conjugated to maleimide lipids incorporated into 200-nm-sized liposomes and incubated in solution with DDB. Liposomes were labeled with 0.1% rhodamine–PE. (B) Representative kymographs of Rab6a^GDP versus Rab6a^GTP liposomes moving along microtubule in the presence of DDB_FL. Horizontal dashed lines represent liposomes transiently entering the field of focus. (C) Quantification of number of motile Rab6a^GDP or Rab6a^GTP liposomes when incubated with DDB_FL; mean and SEM from n = 3 independent experiments (each experiment measuring a minimum of 30 microtubules; runs for Rab6a^GDP occurred very infrequently). (D) Quantification of the number of motile Rab6a^GTP liposomes moving on microtubules when incubated with DDB_FL (WT vs. mutant); mean and SEM from n = 3 independent experiments (each experiment measuring a minimum of 30 microtubules); **, P ≤ 0.01; ***, P ≤ 0.001.