Fate mapping the avian neural plate with quail/chick chimeras: origin of prospective median wedge cells.
The origin of prospective M cells, which are median neuroepithelial cells that become wedge-shaped during bending of the neural plate and eventually form the midline floor of the neural tube, was determined by constructing quail/chick chimeras and using the quail nucleolar marker to identify quail donor cells in chick host blastoderms. Two possible sites of prospective M-cell origin in the epiblast were examined: a single, midline rudiment located just rostral to Hensen's node and paired rudiments flanking the cranial part of the primitive streak. Our results suggest that M cells arise exclusively from the midline, prenodal rudiment. From this rudiment, M cells extend caudally throughout the entire length of the neuroepithelium. This new information on the origin of prospective M cells will aid in the analysis of their role in neurulation.
Schoenwolf
G C
GC
Department of Anatomy, University of Utah, School of Medicine, Salt Lake City 84132.
Bortier
H
H
Vakaet
L
L
D000818:Animals; D002490:Central Nervous System / Q000196:embryology*; D002642:Chick Embryo / Q000254:growth & development*; D002678:Chimera; D009457:Neuroglia / Q000502:physiology*; D011784:Quail / Q000196:embryology*