Fate mapping of the mouse prosencephalic neural plate

Little is known about the behavior of cells within the anterior neural plat e or tube in developing mammalian embryos in utero due to technical limitat ions. Here we labeled neuroepithelial cells with vital dye and traced their siblings for 1 or 2 days using the whole-embryo culture system. The result s demonstrated that rostral cell movement from the midbrain to the forebrai n in the mouse neural plate was restricted at the boundary by the five-somi te stage. Coincident with restriction of cell intermingling, expression of a transcription factor, Pax6, and a cell adhesion molecule, cadherin-6, com menced to demarcate the forebrain compartment. Within this compartment, we also mapped several prospective regions of the telencephalon and diencephal on to the eyes. The fate map of the mouse prosencephalic neural plate was v ery similar to those of other vertebrates, providing evidence that mammalia n-specific brain structures, represented in the cerebral neocortex, could e venly develop along the conserved framework of neuromeres. (C) 2000 Academi c Press.