Two zebrafish mutants, ebony and ivory, uncover benefits of neighborhood on photoreceptor survival.
Zebrafish offer a tractable system for the study of retinal development and degeneration, to provide insights into human retinal degeneration. We have begun to dissect the question of neighborhood effects on photoreceptor differentiation and survival through the isolation and characterization of mutants with retinal degeneration. We describe two mutants, ebony and ivory, isolated through a behavioral screen for blind mutants induced by ethyl nitrosourea mutagenesis. Chimeric analysis was conducted to attempt to rescue the photoreceptor degeneration. In ebony, the photoreceptor cell death was both cell autonomous and nonautonomous in nature, whilst the photoreceptor cell death was strikingly nonautonomous in ivory. The rescue at a distance is in keeping with a putative diffusible survival factor. We propose a density-dependent nonautonomous neighborhood effect to explain these findings.
Goldsmith
Paul
P
Department of Anatomy, University of Cambridge, Downing Site, Cambridge, CB2 3DY, United Kingdom.
Baier
Herwig
H
Harris
William A
WA
D000477:Alkylating Agents / Q000633:toxicity; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D001766:Blindness / Q000139:chemically induced; D002450:Cell Communication / Q000502:physiology; D002678:Chimera; D005038:Ethylnitrosourea / Q000633:toxicity; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D009154:Mutation; D010786:Photoreceptor Cells / Q000473:pathology* / Q000502:physiology*; D012162:Retinal Degeneration / Q000235:genetics* / Q000503:physiopathology; D015027:Zebrafish / Q000502:physiology*
D000477:Alkylating Agents; D005038:Ethylnitrosourea