Cytoplasmic Dynein Moves Through Uncoordinated Stepping of the AAA+ Ring Domains

Abstract

Doing the Side Step The molecular motor, dynein, contains two ring domains responsible for its movement along the microtubule. However, how the rings move relative to each other during processive motility and whether dynein processivity requires interhead coordination are unclear. To directly observe how dynein “walks” along microtubules, DeWitt et al. (p. 221 , published online 8 December) performed advanced fluorescence-imaging studies to follow both motor domains of a single dynein motor at nanometer resolution. The data suggest that the two heads do not cooperate during movement, which suggests a fundamentally different mechanism of motility from that observed for other microtubule-based motors.