History
Neural crest was first described in the chick embryo by Wilhelm His in 1868 as "the cord in between" (Zwischenstrang) because of its origin between the neural plate and non-neural ectoderm. He named the tissue ganglionic crest since its final destination was each lateral side of the neural tube where it differentiated into spinal ganglia. During the first half of the 20th century the majority of research on neural crest was done using amphibian embryos which was reviewed by Hörstadius (1950) in a well known monograph.
Cell labeling techniques advanced the field of neural crest because they allowed researchers to visualize the migration of the tissue throughout the developing embryos. In the 1960s Weston and Chibon utilized radioisotopic labeling of the nucleus with tritiated thymidine in chick and amphibian embryo respectively. However, this method suffers from drawbacks of stability, since every time the labeled cell divides the signal is diluted. Modern cell labeling techniques such as rhodamine-lysinated dextran and the vital dye diI have also been developed to transiently mark neural crest lineages.
The quail-chick marking system, devised by Nicole Le Douarin in 1969, was another instrumental technique used to track neural crest cells. Chimeras, generated through transplantation, enabled researchers to distinguish neural crest cells of one species from the surrounding tissue of another species. With this technique, generations of scientists were able to reliably mark and study the ontogeny of neural crest cells.
Read more about this topic: Neural Crest
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