Early Events in the Formation of the Vertebrate Brain
For many years Dr. Easter’s research has focused on the development of the retinotectal pathway in fish and amphibians. Because these animals grow throughout life and continue to add new cells to the retina, they are more accessible and easier to examine than embryos. Dr. Easter’s previous investigations have suggested that retinal axons added late in life probably use the optic fibers that preceded them as guides to the optic tectum. In an attempt to understand the origin of the first axons, Dr. Easter and his colleagues have examined embryonic neural development, and that work is described here. This chapter first covers work done in collaboration with Dr. Jeremy Taylor in the laboratory of Dr. Michael Gaze on the early development of the optic pathway and its microenvironment in Xenopus laevis (Easter and Taylor, 1989). Second, the early neuronal scaffolding in the zebrafish brain, work done in collaboration with Drs. Stephen Wilson and Linda Ross and Mr. Timothy Parrett (Wilson et al., 1990), is described.
KeywordsGrowth Cone Anterior Commissure Optic Tectum Xenopus Embryo Posterior Commissure
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