PUBLICATION
The first retinal axons and their microenvironment in zebrafish: cryptic pioneers and the pretract
- Authors
- Burrill, J.D. and Easter, S.S. Jr.
- ID
- ZDB-PUB-961014-149
- Date
- 1995
- Source
- The Journal of neuroscience : the official journal of the Society for Neuroscience 15: 2935-2947 (Journal)
- Registered Authors
- Burrill, John, Easter, Stephen S., Jr.
- Keywords
- none
- MeSH Terms
-
- Aging/physiology*
- Animals
- Axons/physiology*
- Axons/ultrastructure
- Embryo, Nonmammalian/physiology
- Optic Nerve/embryology
- Optic Nerve/growth & development
- Optic Nerve/physiology*
- Retina/embryology
- Retina/growth & development
- Retina/physiology*
- Superior Colliculi/embryology
- Superior Colliculi/growth & development
- Superior Colliculi/physiology*
- Zebrafish/embryology
- Zebrafish/physiology*
- PubMed
- 7722638 Full text @ J. Neurosci.
Citation
Burrill, J.D. and Easter, S.S. Jr. (1995) The first retinal axons and their microenvironment in zebrafish: cryptic pioneers and the pretract. The Journal of neuroscience : the official journal of the Society for Neuroscience. 15:2935-2947.
Abstract
The initial development of the optic tract was studied with light and electron microscopy in the zebrafish (Danio rerio). Intraocular injections of the fluorescent marker, 1,1'- dioctadecyl-3,3,3',3' tetramethylindocarbocyanine perchlorate (dil), labeled retinal axons and growth cones anterogradely, and injections of dil into the optic chiasm labeled retinal ganglion cells retrogradely. Labeled tissue was photoconverted and examined electron microscopically. The ventronasal retinal quadrant produced the first growth cones. They were the first growth cones in the optic stalk. The leading retinal growth cones, typically 4-10 in number, advanced alongside the tract of the postoptic commissure but rarely sent filopodia into it and never wrapped its axons. Instead, the retinal growth cones followed a pretract, a subpial region that was morphologically distinct from its surroundings and extended out in front of the leading growth cones, presaging the optic tract. Thus, the retinal growth cones, previously thought to be followers of preexisting axons, are actually cryptic pioneers whose proximity to the earlier axons masks their pioneering nature. We suggest that cryptic pioneers and pretracts are probably common elsewhere in the nervous system.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping