Essential Function of Dicer in Resolving DNA Damage in the Rapidly Dividing Cells of the Developing and Malignant Cerebellum

Cell Rep. 2016 Jan 12;14(2):216-24. doi: 10.1016/j.celrep.2015.12.037. Epub 2015 Dec 31.

Abstract

Maintenance of genomic integrity is critical during neurodevelopment, particularly in rapidly dividing cerebellar granule neuronal precursors that experience constitutive replication-associated DNA damage. As Dicer was recently recognized to have an unexpected function in the DNA damage response, we examined whether Dicer was important for preserving genomic integrity in the developing brain. We report that deletion of Dicer in the developing mouse cerebellum resulted in the accumulation of DNA damage leading to cerebellar progenitor degeneration, which was rescued with p53 deficiency; deletion of DGCR8 also resulted in similar DNA damage and cerebellar degeneration. Dicer deficiency also resulted in DNA damage and death in other rapidly dividing cells including embryonic stem cells and the malignant cerebellar progenitors in a mouse model of medulloblastoma. Together, these results identify an essential function of Dicer in resolving the spontaneous DNA damage that occurs during the rapid proliferation of developmental progenitors and malignant cells.

Keywords: apoptosis; dicer; embryonic stem cells; medulloblastoma; p53; replicative stress.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Proliferation
  • Cerebellum / cytology
  • Cerebellum / metabolism*
  • DEAD-box RNA Helicases / genetics*
  • DEAD-box RNA Helicases / metabolism*
  • DNA Damage
  • Mice
  • Neural Stem Cells / physiology*
  • Ribonuclease III / genetics*
  • Ribonuclease III / metabolism*

Substances

  • DICER1 protein, human
  • Ribonuclease III
  • DEAD-box RNA Helicases