Figure 9.

Studies in the presence of inhibitors confirm that the plus- and minus-end directions have been scored correctly. The microtubule gliding assay was analyzed in the presence of known inhibitors of kinesin and dynein. One millimolar AMP-PNP was used to preferentially inhibit kinesin; 5 μM vanadate was used to preferentially inhibit cytoplasm dynein. The direction of movement (or lack of movement) was scored, and the percentage of total microtubules was plotted as a pie graph as indicated. The difference, before and after the inhibitor, of each pie slice is presented at the bottom as percentage change [(a₂ − a₁)/a₁ × 100%]. Number was 54, 24, 35, and 51 for the experiments + ATP, 1 mM AMP-PNP, + ATP, and 5 μM vanadate, respectively.