PUBLICATION
Two additional midline barriers function with midline lefty1 expression to maintain asymmetric Nodal signaling during left-right axis specification in zebrafish
- Authors
- Lenhart, K.F., Lin, S.Y., Titus, T.A., Postlethwait, J.H., Burdine, R.D.
- ID
- ZDB-PUB-111011-2
- Date
- 2011
- Source
- Development (Cambridge, England) 138(20): 4405-4410 (Journal)
- Registered Authors
- Burdine, Rebecca, Lin, Shin-Yi, Postlethwait, John H., Titus, Tom A.
- Keywords
- nodal, southpaw, zebrafish, bmp, left-right asymmetry, midline barrier, lefty
- MeSH Terms
-
- Activin Receptors, Type I/genetics
- Activin Receptors, Type I/metabolism
- Animals
- Base Sequence
- Body Patterning/genetics
- Body Patterning/physiology
- Bone Morphogenetic Protein 4/genetics
- Bone Morphogenetic Protein 4/metabolism
- Bone Morphogenetic Proteins/genetics
- Bone Morphogenetic Proteins/metabolism
- DNA Primers/genetics
- Gene Expression Regulation, Developmental
- Heart/embryology
- Left-Right Determination Factors/genetics
- Left-Right Determination Factors/metabolism*
- Ligands
- Mesoderm/embryology
- Mesoderm/metabolism
- Models, Biological
- Mutation
- Nodal Protein/genetics
- Nodal Protein/metabolism*
- Notochord/embryology
- Notochord/metabolism
- Signal Transduction
- Zebrafish/embryology*
- Zebrafish/genetics
- Zebrafish/metabolism*
- Zebrafish Proteins/genetics
- Zebrafish Proteins/metabolism*
- PubMed
- 21937597 Full text @ Development
Citation
Lenhart, K.F., Lin, S.Y., Titus, T.A., Postlethwait, J.H., Burdine, R.D. (2011) Two additional midline barriers function with midline lefty1 expression to maintain asymmetric Nodal signaling during left-right axis specification in zebrafish. Development (Cambridge, England). 138(20):4405-4410.
Abstract
Left-right (L/R) patterning is crucial for the proper development of all vertebrates and requires asymmetric expression of
nodal in the lateral plate mesoderm (LPM). The mechanisms governing asymmetric initiation of nodal have been studied extensively, but because Nodal is a potent activator of its own transcription, it is also crucial to understand
the regulation required to maintain this asymmetry once it is established. The ‘midline barrier’, consisting of lefty1 expression, is a conserved mechanism for restricting Nodal activity to the left. However, the anterior and posterior extremes
of the LPM are competent to respond to Nodal signals yet are not adjacent to this barrier, suggesting that lefty1 is not the only mechanism preventing ectopic Nodal activation. Here, we demonstrate the existence of two additional midline
barriers. The first is a ‘posterior barrier’ mediated by Bmp signaling that prevents nodal propagation through the posterior LPM. In contrast to previous reports, we find that Bmp represses Nodal signaling independently
of lefty1 expression and through the activity of a ligand other than Bmp4. The ‘anterior barrier’ is mediated by lefty2 expression in the left cardiac field and prevents Nodal activation from traveling across the anterior limit of the notochord
and propagating down the right LPM. Both barriers appear to be conserved across model systems and are thus likely to be present
in all vertebrates
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping