TRACING NEURONAL LINEAGES
A number of researches study how embryonic
neurons find their positions by following the guides provided by radial glia
and by settling where they find compatible membrane “stickiness” (Linda Faye Lehman & Giuseppe Perrella, How cortical
interneurons find their address. BM&L-INTERNATIONAL, Views and News,
09/12, 2003), but the brain is an overwhelmingly
complex organization. Is there any way of following the life lines of cells
within this complexity? Can we track their wanderings from place of birth (proliferative
zone) to their final position in the mature brain? On the face of it, with a
jungle of 1011 cells, this seems a very tall order indeed. If we
inject stem cells in the proliferative zones with a marker such as horseradish
peroxidase subsequent cell divisions will so dilute the histochemical that it
will soon be impossible to locate.
BM&L
discussed two of the newer techniques: retrovirus tagging and enhancer
trapping.