<i>Atoh1</i> drives the heterogeneity of the pontine nuclei neurons and promotes their differentiation.

Abstract

Pontine nuclei (PN) neurons mediate the communication between the cerebral cortex andthe cerebellum to refine skilled motor functions. Prior studies showed that PN neurons fall into two subtypes based on their anatomic location and region-specific connectivity, but the extent of their heterogeneity and its molecular drivers remain unknown. <i>Atoh1</i> encodes a transcription factor that is expressed in the PN precursors. We previously showed that partial loss of <i>Atoh1</i> function in mice results in delayed PN development and impaired motor learning. In this study, we performed single-cell RNA sequencing to elucidate the cell state-specific functions of <i>Atoh1</i> during PN development and found that <i>Atoh1</i> regulates cell cycle exit, differentiation, migration, and survival of PN neurons. Our data revealed six previously not known PN subtypes that are molecularly and spatially distinct. We found that the PN subtypes exhibit differential vulnerability to partial loss of <i>Atoh1</i> function, providing insights into the prominence of PN phenotypes in patients with <i>ATOH1</i> missense mutations.