Little is known about the behavior of cells within the anterior neural plate or tube in developing mammalian embryos in utero due to technical limitations. Here we labeled neuroepithelial cells with vital dye and traced their siblings for 1 or 2 days using the whole-embryo culture system. The results demonstrated that rostral cell movement from the midbrain to the forebrain in the mouse neural plate was restricted at the boundary by the five-somite stage. Coincident with restriction of cell intermingling, expression of a transcription factor, Pax6, and a cell adhesion molecule, cadherin-6, commmenced to demarcate the forebrain compartment. Within this compartment, we also mapped several prospective regions of the telencephalon and diencephalon to the eyes. The fate map of the mouse prosencephalic neural plate was very similar to those of other vertebrates, providing evidence that mammalian-specific brain structures, represented in the cerebral neocortex, could evenly develop along the conserved framework of neuromeres.
Copyright 2000 Academic Press.