Dynein heavy chains are minus end-directed microtubule motor proteins. Axonemal dynein complexes interact with adjacent microtubules in the axoneme. Coordinated binding and release of the axonemal dyneins slide the microtubules relative to each other causing the axoneme to bend driving ciliary and flagellar motion. Axonemal outer arm dynein heavy chains are the microtubule-binding motor protein of the dynein outer arm. (Adapted from FBrf0230280).