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Journal of Neuroscience, Vol 10, 1299-1308, Copyright © 1990 by Society for Neuroscience
Pathfinding by identified growth cones in the spinal cord of zebrafish embryos
JY Kuwada, RR Bernhardt and AB Chitnis
Department of Biology, University of Michigan, Ann Arbor 48109.
The spinal cord of early (18-20 hr) zebrafish embryos consists of a small
number of neurons per hemisegment. The earliest neurons are identified and
project growth cones that follow stereotyped, cell- specific pathways to
reach their termination sites. We have studied the pathways taken by 4 of
the early neurons in order to delineate the cells and structures their
growth cones encounter during pathfinding. These neurons are 3 classes of
commissural neurons (CoPA, CoSA, and CoB), which have contralateral
longitudinal axons, and the VeLD neuron, which has an ipsilateral
longitudinal axon. These growth cones encounter a defined set of cells and
structures. Commissural growth cones appear to bypass the longitudinal
axons of several identified neurons, including those from contralateral
commissural neurons they encounter immediately following projection from
the cell bodies. In contrast, these growth cones appear to extend in
association with the longitudinal axons of commissural cells after crossing
the ventral midline. Another set of cells of interest are the floor plate
cells, a row of cells that constitute the ventral floor of the cord. At the
floor plate growth cones exhibit cell-specific behaviors which may be
influenced by the floor plate. (1) The floor plate may attract specific
growth cones. The CoPA, CoSA, CoB, and VeLD growth cones all extend to the
floor plate while other identified growth cones do not. (2) The floor plate
may mediate cell-specific turns and induce some growth cones to cross the
midline while inhibiting others from doing so. The commissural growth cones
extend directly under the floor plate to cross the midline and turn
anterior (CoPA and CoSA) or bifurcate (CoB); the VeLD growth cone turns
away from the midline and extends posteriorly. (3) The floor plate may
mediate changes in the substrate affinities of growth cones. Commissural
growth cones bypass longitudinal pathways before they have encountered the
floor plate, but not after. The description of pathfinding by these growth
cones suggests that some elements in their environment are ignored while
others are not. Most interestingly, a single structure (the floor plate)
may mediate multiple, cell-specific effects on spinal growth cones.
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|
|
|
|
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|
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