Onset and time course of apoptosis in the developing zebrafish retina.
Cell Tissue Res
; 306(2): 199-207, 2001 Nov.
Article
em En
| MEDLINE
| ID: mdl-11702231
ABSTRACT
In mammalian development, apoptosis spreads over the retina in consecutive waves and induces a remarkable amount of cell loss. No evidence for such consecutive waves has been revealed in the fish retina so far. As the zebrafish is of growing importance as a model for retinal development and for degenerative retinal diseases, we examined the onset and time course of apoptosis in the developing zebrafish retina and in adult fish. We found that apoptosis peaked in the ganglion cell layer (GCL) and inner nuclear layer (INL) in early developmental stages (3-4 days post-fertilization; dpf) followed by a second, but clearly smaller wave at 6-7dpf. Apoptosis in the outer nuclear layer (ONL) started at 5dpf and peaked at 7dpf. This late-onset high peak of apoptosis of photoreceptors is different from that of all other species examined to date. With 1.09% of cells in the GCL and 1.10% in the ONL being apoptotic, the rate of apoptosis in the developing zebrafish retina was conspicuously lower than that observed in other vertebrates (up to 50% in GCL). During development (2-21dpf), apoptotic waves were most obvious in the central retina, whereas in the periphery near the marginal zone (MZ), apoptosis was much lower; in adult animals, practically no apoptosis was present in the central retina but it still occurred near the MZ. Our data show that the onset and time course of apoptosis in the GCL and INL of the zebrafish is comparable with other vertebrates; however, the amount of apoptosis is clearly reduced. Thus, apoptosis in the zebrafish retina may serve more as a mechanism for the fine tuning of the retinal neuronal network after mitotic waves during development or in remaining mitotic areas than as a mechanism for eliminating large numbers of excess cells.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Retina
/
Células Ganglionares da Retina
/
Peixe-Zebra
/
Apoptose
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Cell Tissue Res
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Alemanha