J. Fontaineperus et al., MOUSE CHICK CHIMERA - A NEW MODEL TO STUDY THE IN OVO DEVELOPMENTAL POTENTIALITIES OF MAMMALIAN SOMITES, Development, 121(6), 1995, pp. 1705-1718
Chimeras were prepared by transplanting somites from 9-day post-coitum
mouse embryos or semitic dermomyotomes from 10-day post-coltum mouse
embryos into 2-day-old chick embryos at different axial levels. Mouse
semitic cells then differentiated in ovo in dermis, cartilage and skel
etal muscle as they normally do in the course of development and were
able to migrate into chick host limb. To trace the behavior of semitic
myogenic stem cells more closely, somites arising from mice bearing a
transgene of the desmin gene linked to a reporter gene coding for Esc
herichia coli beta-galactosidase (lacZ) were grafted in ovo. Interesti
ngly, the transgene was rapidly expressed in myotomal muscles derived
from implants. In the limb muscle mass, positive cells were found seve
ral days after implantation. Activation of desmin nls lacZ also occurr
ed in in vitro cultures of somite-derived cells. Our experimental meth
od facilitates investigation of the mechanisms of mammalian developmen
t, allowing the normal fate of implanted mouse cells to be studied and
providing suitable conditions for identification of descendants of ge
netically modified cells.