Long-Distance Neuronal Migration in the Adult Mammalian Brain

TLDR

Neuronal precursors normally migrate from ventricular zones during development, and adult mouse SVZ cells continue to proliferate, yet their in vivo fate remains unclear. The study grafted transgene‑expressing adult SVZ cells into adult mouse brains and tracked endogenous SVZ cells using tritiated thymidine or a vital dye. Both grafted and endogenous SVZ cells migrated long distances and differentiated into olfactory‑bulb neurons.

Abstract

During the development of the mammalian brain, neuronal precursors migrate to their final destination from their site of birth in the ventricular and subventricular zones (VZ and SVZ, respectively). SVZ cells in the walls of the lateral ventricle continue to proliferate in the brain of adult mice and can generate neurons in vitro, but their fate in vivo is unknown. Here SVZ cells from adult mice that carry a neuronal-specific transgene were grafted into the brain of adult recipients. In addition, the fate of endogenous SVZ cells was examined by microinjection of tritiated thymidine or a vital dye that labeled a discrete population of SVZ cells. Grafted and endogenous SVZ cells in the lateral ventricle of adult mice migrate long distances and differentiate into neurons in the olfactory bulb.