PUBLICATION
Complex Regulation of cyp26a1 Creates a Robust Retinoic Acid Gradient in the Zebrafish Embryo
- Authors
- White, R.J., Nie, Q., Lander, A.D., and Schilling, T.F.
- ID
- ZDB-PUB-071125-27
- Date
- 2007
- Source
- PLoS Biology 5(11): e304 (Journal)
- Registered Authors
- Schilling, Tom
- Keywords
- Embryos, Hindbrain, Morphogens, Zebrafish, Fibroblast growth factor, Somites, Yellow fluorescent protein, Mesoderm
- MeSH Terms
-
- Gene Expression Regulation, Developmental*
- Zebrafish/embryology*
- Cytochrome P-450 Enzyme System/genetics*
- Cytochrome P-450 Enzyme System/metabolism
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/metabolism
- Central Nervous System/embryology*
- Animals
- Tretinoin/metabolism*
- Body Patterning/genetics*
- Embryo, Nonmammalian/enzymology*
- Signal Transduction
- PubMed
- 18031199 Full text @ PLoS Biol.
Citation
White, R.J., Nie, Q., Lander, A.D., and Schilling, T.F. (2007) Complex Regulation of cyp26a1 Creates a Robust Retinoic Acid Gradient in the Zebrafish Embryo. PLoS Biology. 5(11):e304.
Abstract
Positional identities along the anterior-posterior axis of the vertebrate nervous system are assigned during gastrulation by multiple posteriorizing signals, including retinoic acid (RA), fibroblast growth factors (Fgfs), and Wnts. Experimental evidence has suggested that RA, which is produced in paraxial mesoderm posterior to the hindbrain by aldehyde dehydrogenase 1a2 (aldh1a2/raldh2), forms a posterior-to-anterior gradient across the hindbrain field, and provides the positional information that specifies the locations and fates of rhombomeres. Recently, alternative models have been proposed in which RA plays only a permissive role, signaling wherever it is not degraded. Here we use a combination of experimental and modeling tools to address the role of RA in providing long-range positional cues in the zebrafish hindbrain. Using cell transplantation and implantation of RA-coated beads into RA-deficient zebrafish embryos, we demonstrate that RA can directly convey graded positional information over long distances. We also show that expression of Cyp26a1, the major RA-degrading enzyme during gastrulation, is under complex feedback and feedforward control by RA and Fgf signaling. The predicted consequence of such control is that RA gradients will be both robust to fluctuations in RA synthesis and adaptive to changes in embryo length during gastrulation. Such control also provides an explanation for the fact that loss of an endogenous RA gradient can be compensated for by RA that is provided in a spatially uniform manner.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping