| Caption: |
Motor Protein: An Animated Model of Kinesin "Walking" Along a Microtubule: This clip offers a three-dimensional animated model of kinesin walking, based on X-ray crystallographic imagery. The process begins as one of the two kinesin heads (blue) binds to a microtubule (green and white), releasing its bound ADP, and binding a new molecule of ATP to the "neck linker" region (causing a red to yellow color change in the linker). Subsequently the second head binds and exchanges ADP for ATP as the first head hydrolyzes its ATP and releases Pi. ATP hydrolysis causes the first head to detach from the microtubule and swing forward in what has been described as a "cartoon duckwalk" and rebind to the microtubule. The kinesin heads wobble and flap when unbound in realistic Brownian motion. See text Fig 7.37. Run time: 0:45 |