The Function ofsilberblickin the Positioning of the Eye Anlage in the Zebrafish Embryo
- 1 April 1997
- journal article
- Published by Elsevier BV in Developmental Biology
- Vol. 184 (1), 85-94
- https://doi.org/10.1006/dbio.1997.8511
Abstract
In zebrafish, as in other vertebrates, an initially singular eye field within the neural plate has to split during morphogenesis to allow the development of two separated eyes. It has been suggested that anterior progression of midline tissue within the neural plate is involved in the bilateralization of the eye field. Mutations in the recently identified silberblick (slb) gene cause an incomplete separation of the eyes. During gastrulation and early somitogenesis, the ventral midline of the central nervous system (CNS) together with the underlying axial mesendoderm is shortened and broadened in slb embryos. While in wild-type embryos the ventral CNS midline extends to the anterior limit of the neural plate at the end of gastrulation, there is a gap between the anterior tip of the ventral CNS midline and the anterior edge of the neural plate in slb. To investigate the cause for the shortening of the ventral CNS midline in slb we determined the fate of labeled ventral CNS midline cells in wild-type and slb embryos at different stages of development. In slb, anterior migration of ventral CNS midline cells is impaired, which indicates that migration of these cells is needed for elongation of the ventral CNS midline. The anterior shortening of the ventral CNS midline in slb leads to medial instead of bilateral induction of optic stalks followed by a partial fusion of the eyes at later developmental stages. The analysis of the slb phenotype indicates that anterior migration of midline cells within the neural plate is required for proper induction and subsequent bilateralization of an initially singular eye field. These findings may therefore provide a starting point in elucidating the role of neural plate morphogenesis in positioning of the eyes.Keywords
This publication has 35 references indexed in Scilit:
- Cyclopia and defective axial patterning in mice lacking Sonic hedgehog gene functionNature, 1996
- Patterning activities of vertebrate hedgehog proteins in the developing eye and brainCurrent Biology, 1995
- Differential expression of fork head genes during early Xenopus and zebrafish developmentDevelopmental Genetics, 1995
- Combinatorial expression of three zebrafish genes related to distal- less: part of a homeobox gene code for the headJournal of Neuroscience, 1994
- Sonic hedgehog, a member of a family of putative signaling molecules, is implicated in the regulation of CNS polarityCell, 1993
- Role of the floor plate in axonal patterning in the zebrafish CNSNeuron, 1992
- Elimination of a brain tract increases errors in pathfinding by follower growth cones in the zebrafish embryoNeuron, 1991
- The cyclops mutation blocks specification of the floor plate of the zebrafish central nervous systemNature, 1991
- A new fate map for Salmo gairdneriJournal of Experimental Zoology, 1973
- Experimental studies on the development of the eye. III. The effect of the substrate (‘Unterlagerung’) on the heterotopic development of median and lateral strips of the anterior end of the neural plate of amblystomaJournal of Experimental Zoology, 1930