ATAT1-enriched vesicles promote microtubule acetylation via axonal transport

Microtubules are polymerized dimers of alpha- and beta-tubulin that underlie a broad range of cellular activities. Acetylation of alpha-tubulin by the acetyltransferase ATAT1 modulates microtubule dynamics and functions in neurons. However, it remains unclear how this enzyme acetylates microtubules over long distances in axons. Here, we show that loss of ATAT1 impairs axonal transport in neurons in vivo, and cell-free motility assays confirm a requirement of alpha-tubulin acetylation for proper bidirectional vesicular transport. Moreover, we demonstrate that the main cellular pool of ATAT1 is transported at the cytosolic side of neuronal vesicles that are moving along axons. Together, our data suggest that axonal transport of ATAT1-enriched vesicles is the predominant driver of alpha-tubulin acetylation in axons.