Oligodendrocyte Progenitors Balance Growth With Self-Repulsion to Achieve Homeostasis in the Adult Brain

Nat Neurosci. 2013 Jun;16(6):668-76. doi: 10.1038/nn.3390. Epub 2013 Apr 28.

Abstract

The adult CNS contains an abundant population of oligodendrocyte precursor cells (NG2(+) cells) that generate oligodendrocytes and repair myelin, but how these ubiquitous progenitors maintain their density is unknown. We generated NG2-mEGFP mice and used in vivo two-photon imaging to study their dynamics in the adult brain. Time-lapse imaging revealed that NG2(+) cells in the cortex were highly dynamic; they surveyed their local environment with motile filopodia, extended growth cones and continuously migrated. They maintained unique territories though self-avoidance, and NG2(+) cell loss though death, differentiation or ablation triggered rapid migration and proliferation of adjacent cells to restore their density. NG2(+) cells recruited to sites of focal CNS injury were similarly replaced by a proliferative burst surrounding the injury site. Thus, homeostatic control of NG2(+) cell density through a balance of active growth and self-repulsion ensures that these progenitors are available to replace oligodendrocytes and participate in tissue repair.

Publication types

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

MeSH terms

  • Animals
  • Cell Count
  • Cell Death / physiology
  • Cell Differentiation / physiology*
  • Cell Movement / physiology
  • Cell Proliferation
  • Cerebral Cortex / cytology*
  • Cerebral Cortex / physiology
  • Homeostasis / physiology*
  • Mice
  • Mice, Transgenic
  • Neural Stem Cells / physiology*
  • Oligodendroglia / physiology*
  • Time-Lapse Imaging