Dynein motors: How AAA+ ring opening and closing coordinates microtubule binding and linker movement.

Dyneins are a family of motor proteins that move along the microtubule. Motility is generated in the motor domain, which consists of a ring of six AAA+ (ATPases associated with diverse cellular activities) domains, the linker and the microtubule-binding domain (MTBD). The cyclic ATP-hydrolysis in the AAA+ ring causes the remodelling of the linker, which creates the necessary force for movement. The production of force has to be synchronized with cycles of microtubule detachment and rebinding to efficiently create movement along the microtubule. The analysis of four dynein motor domain crystal structures in the essay presented here provides evidence that this crucial coordination is carried out by open/closed AAA+ ring conformations.