UNDERSTANDING INDIVIDUAL DIFFERENCES IN
BRAIN
Neuronal
somatic diversification remains a central topic for understanding individual
differences in brain organization and function. Muotri et al (Somatic mosaicism in neuronal precursor cells mediated by L1
retrotranposition. Nature 435, 903-910, 2005)
show that an engineered human LINE-1 (L-1) element can retro-transpose in
neuronal precursors derived from rat hippocampus neural stem cells. The
resulting retro-transposition events can alter the expression of neuronal
genes, which, in turn, can influence cell neuronal fate in vitro.
The
authors show that retro-transposition of a human L-1 in transgenic mice results
in neuronal somatic mosaicism. These data indicate that neuronal genome might
not be static, but some might be mosaics because of de novo L-1
retro-transposition events.