FIGURE 18-22 Kinesin-1 is regulated by a head-to-tail interaction. In its inhibited form, the head of kinesin-1 folds back and interacts with the tail. This interaction inhibits the ATPase activity of kinesin-1. When the motor encounters an appropriate receptor, here shown on a vesicle, it unfolds (step 1) and is now able to transport the cargo toward the (+) end of a microtubule (step 2). It is not yet clear how the motor dissociates from the cargo when they arrive at the destination, but it involves cargo release and folding back into the inhibited state.