Delta, Notch, and shaggy: Elements of a Lateral Signaling Pathway in Drosophila
This extract was created in the absence of an abstract.
Excerpt
In most invertebrates, the neural precursors for both central and peripheral nervous systems arise in a spaced pattern and are separated by intervening epidermal cells. Each precursor has a unique identity thought to be dependent on the position in the epithelium at which it is born (Taghert et al. 1984; Doe and Goodman, 1985; Doe et al. 1988a,b; Patel et al. 1989). Each precursor produces a defined set of specific neurons in a remarkably stereotyped array (Bate 1976). The generation of spaced precursors from a large area of the embryo may be a means of allowing the segregation of a large number of cells, each with a different positional identity. This mode of development means that an individual cell, the precursor, adopts a fate that is different from that of each of its neighboring cells. There is evidence, however, that at each site, more than one cell initially acquires the...
