Atoh1 Controls Primary Cilia Formation to Allow for SHH-Triggered Granule Neuron Progenitor Proliferation

Dev Cell. 2019 Jan 28;48(2):184-199.e5. doi: 10.1016/j.devcel.2018.12.017.

Abstract

During cerebellar development, granule neuron progenitors (GNPs) proliferate by transducing Sonic Hedgehog (SHH) signaling via the primary cilium. Precise regulation of ciliogenesis, thus, ensures proper GNP pool expansion. Here, we report that Atoh1, a transcription factor required for GNPs formation, controls the presence of primary cilia, maintaining GNPs responsiveness to SHH. Loss of primary cilia abolishes the ability of Atoh1 to keep GNPs in a proliferative state. Mechanistically, Atoh1 promotes ciliogenesis by transcriptionally regulating Cep131, which facilitates centriolar satellite (CS) clustering to the basal body. Importantly, ectopic expression of Cep131 counteracts the effects of Atoh1 loss in GNPs by restoring proper localization of CS and ciliogenesis. This Atoh1-CS-primary cilium-SHH pro-proliferative pathway is also conserved in SHH-type medulloblastoma, a pediatric brain tumor arising from the GNPs. Together, our data reveal how Atoh1 modulates the primary cilium to regulate GNPs development.

Keywords: Atoh1 (Math1); Cep131 (Azi1); Pcm1; centriolar satellites; cerebellar development; granule neuron progenitors; medulloblastoma; primary cilium; sonic hedgehog.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Basic Helix-Loop-Helix Transcription Factors / metabolism*
  • Brain Neoplasms / metabolism
  • Cell Cycle Proteins / metabolism
  • Cell Differentiation / physiology*
  • Cell Proliferation
  • Cerebellar Neoplasms / metabolism
  • Cilia / metabolism*
  • Hedgehog Proteins / metabolism*
  • Medulloblastoma / metabolism
  • Mice, Transgenic
  • Neurogenesis
  • Neurons / metabolism*

Substances

  • ATOH1 protein, human
  • Basic Helix-Loop-Helix Transcription Factors
  • Cell Cycle Proteins
  • Hedgehog Proteins