spacer gif spacer gif spacer gif spacer gif ARCHIVE ANNOUNCEMENT! spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

doi: 10.1242/10.1242/dev.00544

This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Related articles in Development
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Tian, J.
Right arrow Articles by Sampath, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tian, J.
Right arrow Articles by Sampath, K.
Development 130, 3331-3342 (2003)
Copyright © 2003 The Company of Biologists Limited

A temperature-sensitive mutation in the nodal-related gene cyclops reveals that the floor plate is induced during gastrulation in zebrafish

Jing Tian1,2, Caleb Yam2, Gayathri Balasundaram1, Hui Wang1,*, Aniket Gore1,2 and Karuna Sampath1,2,{dagger}

1 Laboratory of Fish Embryology, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604
2 Department of Biological Sciences, 14 Science Drive 4, National University of Singapore, Singapore 117543
* Present address: Department of Biology, University of Virginia, Charlottesville, VA, USA

{dagger} Author for correspondence (e-mail: karuna{at}tll.org.sg)

Accepted 8 April 2003

The floor plate, a specialized group of cells in the ventral midline of the neural tube of vertebrates, plays crucial roles in patterning the central nervous system. Recent work from zebrafish, chick, chick-quail chimeras and mice to investigate the development of the floor plate have led to several models of floor-plate induction. One model suggests that the floor plate is formed by inductive signalling from the notochord to the overlying neural tube. The induction is thought to be mediated by notochord-derived Sonic hedgehog (Shh), a secreted protein, and requires direct cellular contact between the notochord and the neural tube. Another model proposes a role for the organizer in generating midline precursor cells that produce floor plate cells independent of notochord specification, and proposes that floor plate specification occurs early, during gastrulation.

We describe a temperature-sensitive mutation that affects the zebrafish Nodal-related secreted signalling factor, Cyclops, and use it to address the issue of when the floor plate is induced in zebrafish. Zebrafish cyclops regulates the expression of shh in the ventral neural tube. Although null mutations in cyclops result in the lack of the medial floor plate, embryos homozygous for the temperature-sensitive mutation have floor plate cells at the permissive temperature and lack floor plate cells at the restrictive temperature. We use this mutant allele in temperature shift-up and shift-down experiments to answer a central question pertaining to the timing of vertebrate floor plate induction. Abrogation of Cyc/Nodal signalling in the temperature-sensitive mutant embryos at various stages indicates that the floor plate in zebrafish is induced early in development, during gastrulation. In addition, continuous Cyclops signalling is required through gastrulation for a complete ventral neural tube throughout the length of the neuraxis. Finally, by modulation of Nodal signalling levels in mutants and in ectopic overexpression experiments, we show that, similar to the requirements for prechordal plate mesendoderm fates, uninterrupted and high levels of Cyclops signalling are required for induction and specification of a complete ventral neural tube.

Key words: Floor plate, Nodal signalling, cyclops, Zebrafish, Shh, Twhh, Organizer, Temperature-sensitive mutation, Gastrulation, TGFß


Related articles in Development:

Floor-plate induction: where and when

Development 2003 130: 1405. [Full Text]  



This article has been cited by other articles:


Home page
 DevelopmentHome page
J. Tian, B. Andree, C. M. Jones, and K. Sampath
The pro-domain of the zebrafish Nodal-related protein Cyclops regulates its signaling activities
Development, August 1, 2008; 135(15): 2649 - 2658.
[Abstract] [Full Text] [PDF]

Home page
 Genes Dev.Home page
M. Schafer, M. Rembold, J. Wittbrodt, M. Schartl, and C. Winkler
Medial floor plate formation in zebrafish consists of two phases and requires trunk-derived Midkine-a
Genes & Dev., April 15, 2005; 19(8): 897 - 902.
[Abstract] [Full Text] [PDF]

Home page
 DevelopmentHome page
W. H. Norton, M. Mangoli, Z. Lele, H.-M. Pogoda, B. Diamond, S. Mercurio, C. Russell, H. Teraoka, H. L. Stickney, G.-J. Rauch, et al.
Monorail/Foxa2 regulates floorplate differentiation and specification of oligodendrocytes, serotonergic raphe neurones and cranial motoneurones
Development, February 15, 2005; 132(4): 645 - 658.
[Abstract] [Full Text] [PDF]

Home page
 DevelopmentHome page
M. Kapsimali, L. Caneparo, C. Houart, and S. W. Wilson
Inhibition of Wnt/Axin/{beta}-catenin pathway activity promotes ventral CNS midline tissue to adopt hypothalamic rather than floorplate identity
Development, December 1, 2004; 131(23): 5923 - 5933.
[Abstract] [Full Text] [PDF]


© The Company of Biologists Ltd 2003