Retinoic acid signalling centres in the avian embryo identified by sites of expression of synthesising and catabolising enzymes
Article first published online: 28 MAR 2003
Copyright © 2003 Wiley-Liss, Inc.
Volume 227, Issue 1, pages 114–127, May 2003
How to Cite
Blentic, A., Gale, E. and Maden, M. (2003), Retinoic acid signalling centres in the avian embryo identified by sites of expression of synthesising and catabolising enzymes. Dev. Dyn., 227: 114–127. doi: 10.1002/dvdy.10292
- Issue published online: 8 APR 2003
- Article first published online: 28 MAR 2003
- Manuscript Accepted: 5 FEB 2003
- Manuscript Received: 29 OCT 2002
- retinoic acid;
- chick embryo;
Retinoic acid is an important signalling molecule in the developing embryo, but its precise distribution throughout development is very difficult to determine by available techniques. Examining the distribution of the enzymes by which it is synthesised by using in situ hybridisation is an alternative strategy. Here, we describe the distribution of three retinoic acid synthesising enzymes and one retinoic acid catabolic enzyme during the early stages of chick embryogenesis with the intention of identifying localized retinoic acid signalling regions. The enzymes involved are Raldh1, Raldh2, Raldh3, and Cyp26A1. Although some of these distributions have been described before, here we assemble them all in one species and several novel sites of enzyme expression are identified, including Hensen's node, the cardiac endoderm, the presumptive pancreatic endoderm, and the dorsal lens. This study emphasizes the dynamic pattern of expression of the enzymes that control the availability of retinoic acid as well as the role that retinoic acid plays in the development of many regions of the embryo throughout embryogenesis. This strategy provides a basis for understanding the phenotypes of retinoic acid teratology and retinoic acid–deficiency syndromes. Developmental Dynamics 227:114–127, 2003. © 2003 Wiley-Liss, Inc.