Remodeling and activation mechanisms of outer arm dynein revealed by cryo-EM

Cilia are thin microtubule-based protrusions of eukaryotic cells, beating at high frequency to propel the cell in sperms or clear mucus in the respiratory tract. The ciliary beating is driven by the outer arm dynein arms (ODAs) which anchor on the doublet microtubules. Here, we report the ODA complex structure from the native doublet microtubules by cryo-electron microscopy. Our structure reveals how the ODA complex is attached to the doublet microtubule via the docking complex in its native state. Combined with molecular dynamics simulations, we present a model of how the attachment of the ODA complex to the doublet microtubule induces rearrangements and activation mechanisms within the ODA complex.