The aim of the present study was to determine whether the postulated gnathostome duplication from four to eight Hox clusters occurred before or after the split between the actinopterygian and sarcopterygian fish by characterizing Hox genes from the sarcopterygian lungfish, Neoceratodus forsteri. Sin
The fate of cranial neural crest cells in the Australian lungfish, Neoceratodus forsteri
β Scribed by Rolf Ericsson; Jean Joss; Lennart Olsson
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 458 KB
- Volume
- 310B
- Category
- Article
- ISSN
- 1552-5007
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
The cranial neural crest has been shown to give rise to a diversity of cells and tissues, including cartilage, bone and connective tissue, in a variety of tetrapods and in the zebrafish. It has been claimed, however, that in the Australian lungfish these tissues are not derived from the cranial neural crest, and even that no migrating cranial neural crest cells exist in this species. We have earlier documented that cranial neural crest cells do migrate, although they emerge late, in the Australian lungfish. Here, we have used the lipophilic fluorescent dye, DiI, to label premigratory cranial neural crest cells and follow their fate until stage 43, when several cranial skeletal elements have started to differentiate. The timing and extent of their migration was investigated, and formation of mandibular, hyoid and branchial streams documented. Cranial neural crest was shown to contribute cells to several parts of the head skeleton, including the trabecula cranii and derivatives of the mandibular arch (e.g., Meckel's cartilage, quadrate), the hyoid arch (e.g., the ceratohyal) and the branchial arches (ceratobranchials IβIV), as well as to the connective tissue surrounding the myofibers in cranial muscles. We conclude that cranial neural crest migration and fate in the Australian lungfish follow the stereotyped pattern documented in other vertebrates. J. Exp. Zool. (Mol. Dev. Evol.) 310B:345β354, 2008. Β© 2007 WileyβLiss, Inc.
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