Emergence and migration of trunk neural crest cells in a snake, the California Kingsnake (Lampropeltis getula californiae)

Abstract

BackgroundThe neural crest is a group of multipotent cells that emerges after an epithelial-to-mesenchymal transition from the dorsal neural tube early during development. These cells then migrate throughout the embryo, giving rise to a wide variety derivatives including the peripheral nervous system, craniofacial skeleton, pigment cells, and endocrine organs. While much is known about neural crest cells in mammals, birds, amphibians and fish, relatively little is known about their development in non-avian reptiles like snakes and lizards.ResultsIn this study, we show for the first time ever trunk neural crest migration in a snake by labeling it with DiI and immunofluorescence. As in birds and mammals, we find that early migrating trunk neural crest cells use both a ventromedial pathway and an inter-somitic pathway in the snake. However, unlike birds and mammals, we also observed large numbers of late migrating neural crest cells utilizing the inter-somitic pathway in snake.ConclusionsWe found that while trunk neural crest migration in snakes is very similar to that of other amniotes, the inter-somitic pathway is used more extensively by late-migrating trunk neural crest cells in snake.

Chicken trunk neural crest migration visualized with HNK1

“…Nevertheless, chicken is not the only organisms whose neural crest cells express HNK1 epitope. Other squamata, like turtles, snakes and crocodile neural crest are well labeled with HNK1 (Cebra-Thomas et al, 2007; Kundrat, 2008; Reyes et al, 2010). Although the best universal marker for neural crest cells is the transcription factor Sox10 (Cheng et al, 2000; Sauka-Spengler and Bronner-Fraser, 2006), HNK1 as shown above is a reliable and easy marker to use when studying neural crest cells, thus our present approach following on a well-established method by crest researchers and as a practical way to study in detail the migratory pattern of these cells in the chicken embryo.…”

Gene Duplication of endothelin 3 Is Closely Correlated with the Hyperpigmentation of the Internal Organs (Fibromelanosis) in Silky Chickens

“…Although melanoblasts in mammals and birds are known to migrate mainly via the dorsolateral route from the neural crest, those in lower vertebrates are often observed to travel through the ventral route (Collazo et al 1993;Eisen 1994, 1996;Kelsh 2004;Akiyama et al 2006a;Tomlinson et al 2009;Reyes et al 2010). Investigation of Silky chickens could also provide significant clues to recognize the evolutionary divergence of melanoblast migration.…”

Characterization of the trunk neural crest in the bamboo shark, Chiloscyllium punctatum

“…In addition to observing DiI cells in segmented streams along the lateral line in the trunk, we also observed a group of DiI cells at the tail end migrating as a sheet and a smaller number as a stream migrating rostrally on the ventral portion of the tail. Although we do not know the ultimate destiny of these “returning” populations, the same neural crest migratory pattern has been observed in fish (Collazo et al, ) and amphibians (Collazo et al, ) but not in reptiles (Reyes et al, ) or mammals (Kuhlbrodt et al, ). This suggests that the migratory path became lost in nonaquatic gnathostomes.…”

“…Past studies have shown that Sox8 and Sox9 sequences are highly conserved among fish, amphibians, reptiles, and mammals. Even more striking than sequence conservation, however, is the conserved patterns of migration and expression in vertebrate neural crest cells and their derivatives (Horigome et al, ; Bell et al, ; Sauka‐Spengler and Bronner‐Fraser, b; Guth et al, ; Reyes et al, ). This was especially remarkable in the trunk regions of C. punctatum embryos, because segmental migration through the rostral portion of the somites is practically undistinguishable from that of other vertebrates.…”

“…C. punctatum 's Sox9 expression matched the Sox10 migratory patterns observed in teleosts. Expression profiles were particularly similar in delaminated migrating neural crest cells along the trunk and around the developing eye, branchial arches, gut, and peripheral nerves (Horigome et al, ; Bell et al, ; Sauka‐Spengler and Bronner‐Fraser, b; Guth et al, ; Reyes et al, ). Expression patterns seen in this study differ from observations in Xenopus , zebrafish, chicken, and mammals.…”