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.