During the "power stroke"

The motor domain undergoes a conformational change that causes the microtubule-binding stalk to pivot relative to the cargo-binding tail with the result that one microtubule slides relative to the other. This sliding produces the bending movement needed for cilia to beat and propel the cell or other particles. Groups of dynein molecules responsible for movement in opposite directions are activated and inactivated in a coordinated fashion so that the cilia or flagella can bend and flex co-ordinately